CHST (Construction Health and Safety Technician) Exam — Questions and Answers

Question 1: According to the hierarchy of controls, which method is considered the MOST effective way to protect workers from construction hazards?

Engineering controls
Personal protective equipment
Elimination (Correct answer)
Administrative controls

Correct answer: Elimination

Elimination, which involves physically removing the hazard, is the most effective control method in the hierarchy of controls.

Question 2: What does OSHA require regarding access to scaffold platforms more than 2 feet above or below a point of access?

Workers may use scaffold cross-bracing if no other access exists
Access is only required if the scaffold is over 10 feet high
Safe access must be provided such as a ladder, stairway, or ramp (Correct answer)
A portable ladder may be used at any height

Correct answer: Safe access must be provided such as a ladder, stairway, or ramp

OSHA requires safe access — ladder, stairway, ramp, or integral prefabricated scaffold access — whenever the platform is more than 2 feet above or below access points.

Question 3: Which OSHA standard establishes requirements for controlling hazardous energy during servicing and maintenance of machinery?

29 CFR 1926.500
29 CFR 1910.147 (Correct answer)
29 CFR 1910.333
29 CFR 1926.417

Correct answer: 29 CFR 1910.147

29 CFR 1910.147 is the OSHA lockout/tagout standard that controls hazardous energy during servicing and maintenance activities.

Question 4: The 'Management Oversight and Risk Tree' (MORT) incident investigation method is primarily designed to identify:

Which OSHA regulation was violated
Management system deficiencies and oversight failures that allowed the incident (Correct answer)
Financial losses associated with the incident
The exact physical cause of equipment failure

Correct answer: Management system deficiencies and oversight failures that allowed the incident

MORT is a structured analytical tool that uncovers management system failures, inadequate controls, and oversight gaps that allowed hazards to produce an incident.

Question 5: A worker is directing a crane operator near an active roadway. Which struck-by hazard control is considered the hierarchy's first priority?

Issue the worker a high-visibility vest and hard hat
Reduce crane load weight to lower impact risk
Brief the worker on hand signal procedures
Establish a barricaded exclusion zone that eliminates worker exposure to the swing radius (Correct answer)

Correct answer: Establish a barricaded exclusion zone that eliminates worker exposure to the swing radius

Elimination/substitution sits at the top of the hierarchy of controls. Establishing a physical exclusion zone removes workers from the hazard area entirely, which is more effective than PPE or administrative controls that rely on human behavior.

Question 6: Which scenario represents a 'minor tool change' exception that may allow work without LOTO under 29 CFR 1910.147(a)(2)(ii)?

Replacing a large motor using a hoist while equipment is running slowly
Cleaning around energized panels without touching conductors
Lubricating moving parts during normal production
Routine blade changes on a machine with reliable interlocks that allow the worker to control hazardous energy exposure (Correct answer)

Correct answer: Routine blade changes on a machine with reliable interlocks that allow the worker to control hazardous energy exposure

The minor tool change exception applies only when the alternative procedure provides effective protection equivalent to LOTO through reliable interlocks or other engineered controls.

Question 7: Which analysis tool uses a diagram shaped like a fish skeleton to identify multiple root causes of an incident?

5-Whys method
Fault tree analysis
Job hazard analysis
Ishikawa (fishbone) diagram (Correct answer)

Correct answer: Ishikawa (fishbone) diagram

The Ishikawa or fishbone diagram visually maps cause-and-effect relationships to identify multiple contributing factors to an incident.

Question 8: A construction worker is performing hot work inside a confined space with documented atmospheric testing. The work is paused for a 30-minute lunch break. Upon return, the worker should:

Have the entry supervisor verbally confirm it is still safe
Wait 15 additional minutes as a precaution then re-enter
Resume work since the permit is still valid
Re-test the atmosphere before re-entering the space (Correct answer)

Correct answer: Re-test the atmosphere before re-entering the space

Atmospheric conditions can change rapidly during breaks, especially with hot work; retesting before re-entry is required to ensure continued safety.

Question 9: During a safety training needs assessment, a CHSTidentifies that lost-time injuries are concentrated in the fall hazard category. The MOST appropriate next step is to:

Suspend all work at height until an OSHA inspection is requested
Immediately purchase new fall arrest equipment for all workers without further analysis
Analyze which job tasks, crews, and locations are associated with the fall injuries to target training and controls (Correct answer)
Send a generic fall prevention email to the entire workforce

Correct answer: Analyze which job tasks, crews, and locations are associated with the fall injuries to target training and controls

A targeted root-cause analysis of fall incidents identifies specific gaps in training, equipment, or procedures that can be addressed with focused interventions.

Question 10: Under OSHA's Process Safety Management (PSM) standard (29 CFR 1910.119), what quantity of flammable liquids in a single process triggers PSM coverage?

5,000 pounds
10,000 pounds (Correct answer)
1,000 pounds
25,000 pounds

Correct answer: 10,000 pounds

Flammable liquids stored or processed in a single vessel at 10,000 pounds or more above their normal boiling point trigger PSM requirements.

Question 11: A construction worker is exposed to a chemical with a flash point of 80°F (27°C). Under OSHA's flammable liquids standard, this material is classified as which class?

Class IA
Class IB (Correct answer)
Class IIIA
Class II

Correct answer: Class IB

Class IB flammable liquids have flash points below 73°F (23°C) and boiling points at or above 100°F, but a flash point of 80°F falls within Class II (between 73°F and 140°F).

Question 12: A hydrogen sulfide (H₂S) concentration of 300 ppm inside a confined space represents what condition?

An acceptable level that requires increased monitoring
A level requiring use of air-purifying respirators
An IDLH (Immediately Dangerous to Life or Health) condition (Correct answer)
A level that requires ventilation but permits continued entry

Correct answer: An IDLH (Immediately Dangerous to Life or Health) condition

NIOSH establishes the IDLH for hydrogen sulfide at 100 ppm; a concentration of 300 ppm far exceeds this threshold and represents an immediately life-threatening condition requiring immediate evacuation.

Question 13: What action must be taken before working on or near a crane's electrical systems?

Lower the boom to the ground
Notify the site supervisor
Post a spotter at the crane base
Apply lockout/tagout procedures (Correct answer)

Correct answer: Apply lockout/tagout procedures

OSHA's lockout/tagout standard (29 CFR 1910.147) requires energy isolation and lockout before any maintenance on electrically powered crane systems.

Question 14: According to OSHA's Recommended Practices for Safety and Health Programs, what are the seven core elements of an effective Safety and Health Management System?

OSHA compliance audit; risk matrix; safety budget; recordkeeping; inspections; contractor management; performance reviews
Written safety policy; safety committee; PPE program; OSHA 300 Log; first aid kits; emergency plan; safety posters
Safety officer appointment; safety manual; annual training; incident log; insurance coverage; PPE; supervisor inspections
Management Leadership; Worker Participation; Hazard Identification and Assessment; Hazard Prevention and Control; Education and Training; Program Evaluation and Improvement; Communication and Coordination for Multi-employer Worksites (Correct answer)

Correct answer: Management Leadership; Worker Participation; Hazard Identification and Assessment; Hazard Prevention and Control; Education and Training; Program Evaluation and Improvement; Communication and Coordination for Multi-employer Worksites

OSHA's Recommended Practices for Safety and Health Programs identify seven core elements: Management Leadership, Worker Participation, Hazard Identification and Assessment, Hazard Prevention and Control, Education and Training, Program Evaluation and Improvement, and Communication and Coordination for multi-employer worksites.

Question 15: When workers are exposed to noise levels above an eight-hour time-weighted average of _________, OSHA regulation 29 CFR 1926.52 (Occupational Noise Exposure) requires the implementation of a hearing conservation program.

60 decibels (dB)
90 decibels (dB) (Correct answer)
75 decibels (dB)
95 decibels (dB)

Correct answer: 90 decibels (dB)

According to 29 CFR 1926.52, a Hearing Conservation Program, utilizing engineering and administrative controls, must be in place when the eight-hour time-weighted average of noise exceeds 90 dB.

Question 16: A safety program audit reveals that toolbox talks are being conducted but attendance is inconsistent. What is the BEST corrective action?

Post toolbox talk topics on the bulletin board instead
Eliminate toolbox talks and replace with monthly safety meetings
Reduce the frequency of toolbox talks to improve attendance rates
Require supervisors to document attendance and follow up with absent workers (Correct answer)

Correct answer: Require supervisors to document attendance and follow up with absent workers

Documenting attendance and following up ensures accountability while maintaining the frequency and value of regular safety communications.

Question 17: A contractor is working at heights and must decide between a personal fall arrest system and a positioning device. What is the key functional difference?

Positioning devices arrest free falls; personal fall arrest systems limit movement
Positioning devices are required above 10 feet; personal fall arrest systems are required above 6 feet
Both serve the same function but differ only in anchor strength requirements
Personal fall arrest systems stop free falls; positioning devices hold workers in place to work with both hands free (Correct answer)

Correct answer: Personal fall arrest systems stop free falls; positioning devices hold workers in place to work with both hands free

A personal fall arrest system (PFAS) stops a worker after a free fall begins, while a positioning device keeps the worker supported hands-free at an elevated work position.

Question 18: What is the recommended minimum clear width of an egress path on an active construction site to accommodate emergency evacuation?

18 inches
24 inches
28 inches
36 inches (Correct answer)

Correct answer: 36 inches

A minimum 28-inch clear width is specified in many codes, but OSHA and NFPA guidance for construction sites typically recommend at least 36 inches for safe egress.

Question 19: According to ANSI Z490.1 (Criteria for Accepted Practices in Safety, Health, and Environmental Training), a training program should include all of the following EXCEPT:

Clearly stated learning objectives tied to observable behaviors
Identification of the target audience and their learning needs
A method for evaluating whether learners met the objectives
Automatic certification of workers after a single session regardless of demonstrated competency (Correct answer)

Correct answer: Automatic certification of workers after a single session regardless of demonstrated competency

ANSI Z490.1 requires demonstrated competency for certification; automatic certification without assessment violates this standard.

Question 20: Which of the following is a key requirement for an employee to be considered a 'qualified person' for performing electrical work, according to the OSHA 1926 construction standards?

Possessing a degree in electrical engineering.
Holding a valid state electrician's license.
Having training and experience to recognize and avoid the specific electrical hazards involved. (Correct answer)
Having successfully completed a four-year apprenticeship.

Correct answer: Having training and experience to recognize and avoid the specific electrical hazards involved.

OSHA's definition in 1926.32(m) defines a qualified person as one who, through recognized degree, certificate, or professional standing, or by extensive knowledge, training, and experience, has demonstrated the ability to solve problems relating to the work. The critical element is the demonstrated ability and specific training to identify and avoid the hazards associated with the task, not just a general credential.

Question 21: Which type of stored energy must be addressed during LOTO on a hydraulic press in addition to electrical lockout?

Thermal energy from motor heat only
Pneumatic, hydraulic, gravitational, and spring (mechanical) energies (Correct answer)
Chemical energy stored in hydraulic fluid additives
Electrical energy in the hydraulic pump motor only

Correct answer: Pneumatic, hydraulic, gravitational, and spring (mechanical) energies

LOTO must address all forms of hazardous energy including electrical, pneumatic, hydraulic, gravitational, thermal, and mechanical (spring) energy.

Question 22: Which of the following is the primary purpose of conducting an incident investigation on a construction site?

To complete regulatory paperwork for OSHA and the company's insurer.
To determine the financial impact of the incident on the project's budget.
To identify root causes and implement corrective actions to prevent recurrence. (Correct answer)
To assign blame and discipline responsible employees.

Correct answer: To identify root causes and implement corrective actions to prevent recurrence.

The fundamental goal of an incident investigation is to determine the underlying or root causes to prevent similar incidents from happening in the future. While completing paperwork is a requirement and financial impacts are a concern, the core purpose is prevention, not placing blame, which can discourage reporting and hinder the discovery of systemic safety issues.

Question 23: Which instrument is the preferred choice for real-time monitoring of worker exposure to organic vapor solvents on a construction site?

Colorimetric detector tube
Photoionization detector (PID) (Correct answer)
Combustible gas indicator (CGI)
Electrochemical sensor array

Correct answer: Photoionization detector (PID)

A photoionization detector (PID) ionizes organic vapor molecules with UV light and provides real-time, continuous concentration readings well-suited for solvent monitoring.

Question 24: A construction site has an 8-foot deep trench dug entirely in Type A soil. The competent person has observed that heavy vehicle traffic is causing vibrations near the trench. Which of the following is the correct action for the competent person to take?

No action is needed as Type A soil is the most stable.
Slope the trench at an angle of 53 degrees.
Install a warning system for the mobile equipment.
Reclassify the soil and adjust the protective system accordingly. (Correct answer)

Correct answer: Reclassify the soil and adjust the protective system accordingly.

According to OSHA's soil classification system, a soil cannot be classified as Type A if it is subject to vibration. The competent person must re-evaluate and reclassify the soil, which would likely downgrade it to Type B or C, requiring a change in the protective system (e.g., changing the slope angle or using shoring/shielding).

Question 25: A trench is 7 feet deep in Type A soil with no other hazards. Which protective system option is acceptable under OSHA Appendix B?

Sloping at 0.75H:1V (Correct answer)
Vertical walls with timber shoring only
Sloping at 1.5H:1V
No protection required if workers are experienced

Correct answer: Sloping at 0.75H:1V

Type A soil allows a maximum allowable slope of 0.75H:1V (approximately 53 degrees), making it the least flat slope permissible by OSHA.

Question 26: What is the minimum distance a scaffold must be maintained from power lines rated at 50 kV or less?

3 feet
10 feet (Correct answer)
20 feet
7 feet

Correct answer: 10 feet

OSHA 1926.416 requires scaffolds to be kept at least 10 feet away from power lines rated at 50 kV or below.

Question 27: Which Heinrich safety triangle ratio concept suggests that for every major injury there are many minor incidents and near-misses below it?

Heinrich's triangle (1:29:300) (Correct answer)
Domino theory
Pareto principle
Swiss cheese model

Correct answer: Heinrich's triangle (1:29:300)

Heinrich's triangle proposes a ratio of 1 major injury for every 29 minor injuries and 300 near-miss events, emphasizing near-miss investigation to prevent serious incidents.

Question 28: To make sure they are providing the necessary protection against electrical shock, how frequently must electrical insulating gloves be tested?

Annually
As deemed appropriate by visual inspection
Biweekly
Every six months (Correct answer)

Correct answer: Every six months

Electrical insulating gloves must undergo testing every six months in accordance with 29 CFR 1926.97.

Question 29: According to OSHA's Injury and Illness Prevention Program (I2P2) guidance, employee involvement in safety programs primarily serves to:

Eliminate the requirement for written safety plans
Transfer legal liability from the employer to the employees
Reduce the need for formal OSHA compliance programs
Increase hazard identification and worker ownership of safety outcomes (Correct answer)

Correct answer: Increase hazard identification and worker ownership of safety outcomes

Worker participation improves hazard recognition and fosters a safety culture where employees take personal responsibility for safe behaviors.

Question 30: Under OSHA 1926.502, when using a personal fall arrest system, what is the maximum arresting force that may be applied to a worker during a fall?

2,500 lbs
1,200 lbs
1,800 lbs (Correct answer)
3,000 lbs

Correct answer: 1,800 lbs

OSHA 1926.502(d)(16)(ii) limits the maximum arresting force on a worker to 1,800 lbs when a body harness is used, to reduce the risk of injury during fall arrest.

Question 31: A construction safety technician must communicate a change in excavation procedures to multiple subcontractors. What is the MOST effective approach?

Post the updated procedure on the project website
Update the written safety plan and assume subcontractors will read it
Hold a pre-task meeting with all affected subcontractor supervisors and document attendance (Correct answer)
Call each subcontractor's office and leave a voicemail

Correct answer: Hold a pre-task meeting with all affected subcontractor supervisors and document attendance

A pre-task meeting with affected supervisors ensures direct communication, allows for questions, and provides documented proof that the information was conveyed.

Question 32: According to OSHA regulations for personal fall arrest systems (PFAS) in construction, when must the equipment be inspected?

At the beginning of each new project by the site supervisor.
Only after a fall event has occurred.
Annually by a qualified person.
Before each use by the user and annually by a competent person. (Correct answer)

Correct answer: Before each use by the user and annually by a competent person.

OSHA 1926.502(d)(21) requires that personal fall arrest systems be inspected prior to each use for wear, damage, and other deterioration. In addition to this user inspection, the equipment must be inspected at least annually by a competent person.

Question 33: A supervisor needs to store 20 gallons of gasoline indoors on a construction site, but not in a designated inside storage room. According to 29 CFR 1926.152, which method is NOT compliant?

Keeping the storage area free of ignition sources.
Storing it in four approved 5-gallon safety cans outside of a cabinet.
Placing approved safety cans inside an approved flammable liquid storage cabinet.
Storing it in a single 20-gallon drum that is not a DOT-approved container or safety can. (Correct answer)

Correct answer: Storing it in a single 20-gallon drum that is not a DOT-approved container or safety can.

OSHA standard 29 CFR 1926.152(b)(1) states that 'No more than 25 gallons of flammable liquids shall be stored in a room outside of an approved storage cabinet.' Furthermore, 1926.152(a)(1) requires that only approved containers and portable tanks shall be used. Storing the gasoline in a single, non-approved 20-gallon drum violates the container requirement.

Question 34: According to OSHA 29 CFR 1926.651, how deep must an excavation be before a competent person is required to classify soil and implement protective systems?

6 feet
5 feet (Correct answer)
4 feet
3 feet

Correct answer: 5 feet

OSHA 1926.651 requires that excavations 5 feet or deeper have a protective system (sloping, shoring, or trench box) unless the excavation is in stable rock, and a competent person must classify the soil to determine the appropriate system.

Question 35: Under OSHA's Scaffolding Standard (29 CFR 1926 Subpart L), scaffolds must be capable of supporting their own weight plus how many times the maximum intended load?

4 times (Correct answer)
2 times
5 times
3 times

Correct answer: 4 times

OSHA requires scaffolds to be designed, constructed, and loaded so they can support their own weight plus at least four times the maximum intended load.

Question 36: Under OSHA 1926.251(c)(3), what is the required design factor for wire rope slings used in rigging operations?

4:1
3:1
5:1 (the minimum breaking force must be at least 5 times the rated capacity) (Correct answer)
2:1

Correct answer: 5:1 (the minimum breaking force must be at least 5 times the rated capacity)

OSHA 1926.251(c)(3) and ASME B30.9 require a design factor of 5:1 for wire rope slings — the rated capacity of the sling must not exceed one-fifth of the minimum breaking force of the wire rope used.

Question 37: Which soil type is considered the LEAST stable for excavation purposes under the OSHA soil classification system?

Type A
Stable rock
Type B
Type C (Correct answer)

Correct answer: Type C

Type C soil is the least stable of the three soil classifications and includes granular soils such as gravel, sand, and loamy sand.

Question 38: A crane is rated at 40 tons at a 30-foot radius. The same crane at a 50-foot radius will have a rated capacity that is:

Higher, because the longer radius gives more leverage
Equal only if the boom is lengthened proportionally
The same — capacity is fixed regardless of radius
Lower, because greater radius increases overturning moment (Correct answer)

Correct answer: Lower, because greater radius increases overturning moment

As radius increases, the overturning moment grows, so crane capacity decreases — this inverse relationship is fundamental to reading load charts.

Question 39: According to OSHA's Lockout/Tagout standard (29 CFR 1910.147), which of the following is true regarding tagout devices compared to lockout devices?

Tagout devices must be removed by the same employee who attached them, with no exceptions
Tagout provides equivalent protection to lockout in all situations
Tagout may be used only when the energy isolating device is not capable of being locked out (Correct answer)
Tagout is the preferred method when working on electrical systems

Correct answer: Tagout may be used only when the energy isolating device is not capable of being locked out

Under OSHA's LOTO standard, tagout is permitted only when the energy isolating device is not capable of being locked out. Lockout is the preferred method because it physically prevents re-energization, while a tagout is only a warning device.

Question 40: Under OSHA 29 CFR 1926.52, what is the permissible exposure limit (PEL) for occupational noise averaged over an 8-hour workday?

95 dBA TWA
90 dBA TWA (Correct answer)
100 dBA TWA
85 dBA TWA

Correct answer: 90 dBA TWA

OSHA's construction noise PEL is 90 dBA as an 8-hour time-weighted average (TWA). The action level triggering a hearing conservation program is 85 dBA TWA. Exposures above 90 dBA require engineering/administrative controls and/or hearing protection.

Question 41: What is the primary role of the confined space attendant during entry operations?

To assist entrants with work tasks from just inside the entrance
To document entry procedures for compliance records
To continuously test the atmosphere inside the confined space
To remain outside, monitor entrants and conditions, and initiate rescue if needed (Correct answer)

Correct answer: To remain outside, monitor entrants and conditions, and initiate rescue if needed

The attendant must remain outside the permit space, continuously track entrants, maintain communication, monitor for hazards, and initiate emergency rescue procedures without entering the space.

Question 42: Which GHS pictogram indicates an acute toxicity hazard?

Skull and crossbones (Correct answer)
Exclamation mark
Health hazard (silhouette with asterisk)
Flame symbol

Correct answer: Skull and crossbones

The skull and crossbones GHS pictogram indicates acute toxicity (fatal or toxic if ingested, inhaled, or in contact with skin).

Question 43: According to OSHA's scaffold standard, what is the minimum safe working load for scaffold planks used on light-duty scaffolds?

75 lbs/sq ft
25 lbs/sq ft
100 lbs/sq ft
50 lbs/sq ft (Correct answer)

Correct answer: 50 lbs/sq ft

OSHA requires light-duty scaffolds to support at least 25 pounds per square foot of the platform area, but standard plank ratings begin at 50 lbs/sq ft for light-duty classification.

Question 44: What is the PASS technique used for when operating a fire extinguisher?

A method for inspecting fire suppression systems
A procedure for evacuating multi-story buildings
A protocol for reporting fire incidents
A sequence for properly discharging a portable fire extinguisher (Correct answer)

Correct answer: A sequence for properly discharging a portable fire extinguisher

PASS stands for Pull the pin, Aim at the base, Squeeze the handle, and Sweep side to side, which is the correct technique for using a portable fire extinguisher.

Question 45: Which federal agency is primarily responsible for enforcing workplace safety and health standards in the construction industry?

NIOSH
OSHA (Correct answer)
EPA
MSHA

Correct answer: OSHA

OSHA (Occupational Safety and Health Administration) is the federal agency responsible for enforcing workplace safety and health regulations in construction.

Question 46: Under OSHA 29 CFR 1926.21, what are the employer's obligations regarding construction safety training?

Training is only required when a worker receives a safety citation
Employers must instruct each employee in the recognition and avoidance of unsafe conditions and in the regulations applicable to their work environment (Correct answer)
Training requirements only apply to workers with less than 1 year of experience
Employers must provide OSHA 10-hour training to all workers before site entry

Correct answer: Employers must instruct each employee in the recognition and avoidance of unsafe conditions and in the regulations applicable to their work environment

OSHA 1926.21(b)(2) requires employers to instruct each worker to recognize and avoid unsafe conditions and understand the regulations applicable to their work environment, ensuring workers can protect themselves from specific hazards they face.

Question 47: Which NFPA 704 diamond section color indicates health hazard information?

Red (top)
Yellow (right)
Blue (left) (Correct answer)
White (bottom)

Correct answer: Blue (left)

The NFPA 704 diamond uses blue on the left quadrant to indicate health hazards, rated 0–4.

Question 48: What information is NOT required on an OSHA-compliant confined space entry permit?

Authorized entrants and the entry supervisor
The hazards of the permit space and measures to eliminate or control them
The employer's general liability insurance policy number (Correct answer)
Acceptable entry conditions and atmospheric test results

Correct answer: The employer's general liability insurance policy number

Entry permits must contain safety and operational information including space identification, hazards, atmospheric test results, authorized personnel, and emergency procedures—not financial or insurance data.

Question 49: When conducting a job hazard analysis (JHA), which step should be completed FIRST?

Identify corrective actions for each hazard
Assign a risk priority number to each step
Select the employees who will perform the task
Break the job into sequential steps (Correct answer)

Correct answer: Break the job into sequential steps

A JHA begins by breaking the job into its sequential basic steps before hazards can be identified or controls assigned.

Question 50: An OSHA 300 Log must be retained by the employer for a minimum of:

5 years (Correct answer)
3 years
7 years
10 years

Correct answer: 5 years

Under 29 CFR 1904.33, employers must save the OSHA 300 Log, 300-A summary, and 301 forms for 5 years following the end of the calendar year they cover.

Question 51: Which OSHA soil classification represents the least stable, most hazardous condition for excavation work?

Stable Rock
Type B
Type C (Correct answer)
Type A

Correct answer: Type C

Type C is the least stable soil classification under OSHA 1926.652, requiring the most conservative protective system design. It includes cohesionless soils like gravel, sand, and loamy sand, and soils subject to water seepage.

Question 52: Which type of fire extinguisher is most appropriate for a construction site electrical panel fire?

Class D metal extinguisher
Class B foam extinguisher
Class C or ABC dry chemical extinguisher (Correct answer)
Class A water extinguisher

Correct answer: Class C or ABC dry chemical extinguisher

Class C extinguishers are rated for energized electrical equipment, and ABC dry chemical units cover electrical fires along with ordinary combustibles and flammable liquids.

Question 53: Under OSHA's excavation standard (29 CFR 1926 Subpart P), what is the maximum depth of an excavation before protective systems are required?

6 feet
5 feet (Correct answer)
4 feet
3 feet

Correct answer: 5 feet

Protective systems such as sloping, shoring, or trench boxes are required for any excavation 5 feet or deeper, or shallower if the competent person determines a hazard exists.

Question 54: Under OSHA regulations, what must be done when a construction worker does not speak English and falls under a safety training requirement?

Workers must demonstrate English proficiency before working on the site
Training must be provided in the worker's primary language or through a qualified interpreter — training in English only does not satisfy OSHA's requirement if the worker cannot understand it (Correct answer)
The general contractor's safety officer is solely responsible, not the foreman
Posting bilingual safety signs satisfies the training requirement

Correct answer: Training must be provided in the worker's primary language or through a qualified interpreter — training in English only does not satisfy OSHA's requirement if the worker cannot understand it

OSHA requires that training be provided in a form workers can understand. If a worker does not speak English, the employer must provide training in the worker's primary language or through a qualified interpreter.

Question 55: A toolbox talk is BEST described as which type of safety communication?

A comprehensive annual safety training session required by OSHA
A written incident investigation report shared with the crew
A short, informal job-site meeting addressing a specific hazard relevant to current work (Correct answer)
A formal classroom lecture delivered by a certified trainer

Correct answer: A short, informal job-site meeting addressing a specific hazard relevant to current work

Toolbox talks are brief, targeted discussions held at the work site focused on immediate or upcoming hazards.

Question 56: Which rigging configuration provides the highest vertical load capacity for a given sling rated capacity?

Single-leg vertical hitch
Choker hitch
Basket hitch with both legs vertical (Correct answer)
Two-leg bridle at 60° from horizontal

Correct answer: Basket hitch with both legs vertical

A basket hitch with both legs vertical doubles the effective load capacity compared to a single vertical hitch, and is more efficient than angled bridles.

Question 57: When using a chemical that has a flash point of 73°F (23°C) and a boiling point above 95°F (35°C), it is classified as a:

Flammable liquid (Category 2) (Correct answer)
Flammable liquid (Category 1)
Non-flammable solvent
Combustible liquid (Class II)

Correct answer: Flammable liquid (Category 2)

Under GHS/HazCom 2012, a flammable liquid with a flash point ≥23°C and ≤60°C and a boiling point >35°C is classified as Category 2 flammable liquid.

Question 58: Under OSHA's excavation standard (29 CFR 1926 Subpart P), how soon after a hazardous atmosphere is detected must workers be evacuated from an excavation?

Within 30 minutes
Immediately (Correct answer)
After the competent person performs a second test
Within 15 minutes

Correct answer: Immediately

OSHA requires immediate evacuation of workers when a hazardous atmosphere is detected in an excavation until the hazard has been eliminated.

Question 59: When is a stairway, ladder, or ramp required in an excavation?

Only in Type C soil excavations
Whenever heavy equipment is present
Only when the excavation is deeper than 10 feet
When workers must enter an excavation 4 feet or more in depth (Correct answer)

Correct answer: When workers must enter an excavation 4 feet or more in depth

OSHA 1926.651(c)(2) requires a means of egress (ladder, stairway, or ramp) for any excavation 4 feet or deeper.

Question 60: Which document is MOST critical to have completed and communicated before mobilizing to a new construction project?

A site-specific safety plan tailored to the project scope and hazards (Correct answer)
The project schedule and Gantt chart
The subcontractor bid comparison sheet
The project's environmental impact assessment

Correct answer: A site-specific safety plan tailored to the project scope and hazards

A site-specific safety plan addresses the unique hazards, emergency procedures, and safety requirements of the particular project and must be in place before work begins.

Question 61: Which of the following scenarios would require an arc flash hazard analysis per NFPA 70E on a construction site?

Painting an electrical room wall
Working on energized electrical equipment operating at 50 volts or more (Correct answer)
Inspecting a locked-out panel with the cover removed
Replacing a light bulb in a de-energized fixture

Correct answer: Working on energized electrical equipment operating at 50 volts or more

NFPA 70E requires an arc flash risk assessment when workers may be exposed to energized electrical conductors or circuit parts operating at 50 volts or more.

Question 62: A construction employer's written exposure control plan for silica must include which element under 29 CFR 1926.1153?

Workers' personal medical records and PLHCP evaluations
Annual air monitoring results for each individual worker
Description of tasks involving silica exposure and the engineering and work practice controls used (Correct answer)
A list of all silica-containing products on the project

Correct answer: Description of tasks involving silica exposure and the engineering and work practice controls used

The written exposure control plan must describe each task that involves silica exposure, the engineering controls, work practices, and respiratory protection used for each task.

Question 63: A construction supervisor observes a worker using an extension cord with a damaged outer jacket. The BEST immediate corrective action is to:

Test the cord with a GFCI tester before continuing use
Reduce the load on the cord to limit heat generation
Remove the cord from service and replace it with an undamaged cord (Correct answer)
Wrap the damaged section with electrical tape and continue use

Correct answer: Remove the cord from service and replace it with an undamaged cord

Damaged extension cords must be removed from service immediately; repairs by taping do not restore the cord's integrity and are not an acceptable remedy on construction sites.

Question 64: Under OSHA 1910.1200(e), who must have access to the written Hazard Communication Program, and what must it contain?

All employees must have access; it must describe how labels will be used, how SDSs will be maintained, and how employee training will be conducted for each hazardous chemical in the workplace (Correct answer)
The written program is only required for employers with more than 10 workers
It only needs to describe PPE requirements for chemical handling
Only safety officers and managers need access; it only covers storage procedures

Correct answer: All employees must have access; it must describe how labels will be used, how SDSs will be maintained, and how employee training will be conducted for each hazardous chemical in the workplace

OSHA 1910.1200(e) requires a written HazCom program accessible to all employees that describes how the employer will use labels, maintain SDSs, and conduct training for each hazardous chemical in the workplace.

Question 65: What is the primary purpose of a Safety Data Sheet (SDS) Section 8 (Exposure Controls/Personal Protection)?

Identify first aid measures for chemical exposure
List regulatory exposure limits and recommend appropriate PPE (Correct answer)
Provide emergency response telephone numbers
Describe physical and chemical properties of the substance

Correct answer: List regulatory exposure limits and recommend appropriate PPE

SDS Section 8 lists OELs (such as OSHA PELs and ACGIH TLVs) and specifies engineering controls and PPE required to minimize worker exposure.

Question 66: Under OSHA 1904.35, workers have specific rights related to workplace injury records. Which of the following is a protected right?

Workers can be required to sign a release before accessing OSHA records
Only supervisors may view the OSHA 300 Log
Workers must only report injuries through their union representative
The right to report injuries and illnesses without fear of retaliation, and the right to access the OSHA 300 Log (Correct answer)

Correct answer: The right to report injuries and illnesses without fear of retaliation, and the right to access the OSHA 300 Log

OSHA 1904.35 gives workers the right to report work-related injuries and illnesses, protection from retaliation for doing so, and the right to access the OSHA 300 Log and related records.

Question 67: Which of the following is NOT an acceptable method of worker egress from a trench that is 4 feet or more in depth?

Being lifted out by a backhoe bucket (Correct answer)
Steps built into the side of the excavation
Structural ramp designed by a competent person
Ladder placed within 25 feet of workers

Correct answer: Being lifted out by a backhoe bucket

Using a backhoe bucket to lift workers out of a trench is never an acceptable means of egress and violates OSHA safety standards.

Question 68: What is the minimum height at which fall protection must be provided for workers in the construction industry according to OSHA standards?

10 feet
4 feet
8 feet
6 feet (Correct answer)

Correct answer: 6 feet

OSHA requires fall protection for construction workers at heights of 6 feet or more above a lower level under 29 CFR 1926.501.

Question 69: A safety manager notices workers consistently bypass a machine guard. According to behavior-based safety (BBS) principles, the BEST response is to:

Remove the guard and trust workers to self-regulate
Observe the task, identify the antecedents driving the behavior, and redesign the consequence system to reinforce safe behavior (Correct answer)
Immediately terminate workers who bypass guards as a deterrent
Issue written warnings to all workers observed bypassing the guard

Correct answer: Observe the task, identify the antecedents driving the behavior, and redesign the consequence system to reinforce safe behavior

BBS focuses on antecedents and consequences (ABC model) to understand and change behaviors rather than purely punitive responses.

Question 70: A CHST notices workers using spray-applied coatings containing silica in an enclosed space without respiratory protection. The MOST appropriate corrective action is to:

Post warning signs and allow work to continue until end of shift
Increase general ventilation by opening one additional door
Provide half-face respirators with N95 filters to all workers and allow work to resume
Stop work immediately, evacuate the space, and implement engineering controls and proper respiratory protection before resuming (Correct answer)

Correct answer: Stop work immediately, evacuate the space, and implement engineering controls and proper respiratory protection before resuming

Respirable crystalline silica causes silicosis and lung cancer; OSHA's silica standard (29 CFR 1926.1153) requires immediate controls including stopping work if workers are exposed above the action level without protection.

Question 71: Under OSHA 1926.24, what must a construction site fire prevention plan include?

A building floor plan showing exit locations only
Emergency contact numbers and insurance information
List of major fire hazards, procedures for handling and storing flammable materials, ignition source controls, fire protection equipment, and assigned responsibilities for maintaining equipment and controlling hazards (Correct answer)
Only the location of fire extinguishers on the site

Correct answer: List of major fire hazards, procedures for handling and storing flammable materials, ignition source controls, fire protection equipment, and assigned responsibilities for maintaining equipment and controlling hazards

OSHA 1926.24 requires a written fire prevention plan that addresses fire hazards, ignition source control, flammable material storage, fire protection equipment, and responsibilities for plan maintenance.

Question 72: When conducting a pre-task safety analysis for hot work near flammable materials, a CHST should verify that a fire watch remains on duty for at least how long after welding is complete?

Until the next shift begins
30 minutes (Correct answer)
15 minutes
1 hour

Correct answer: 30 minutes

NFPA 51B and most hot work permit programs require a fire watch to remain for a minimum of 30 minutes after hot work is completed.

Question 73: What is the role of a qualified rigger versus a competent person in crane and rigging operations?

A qualified rigger has recognized training/certification; a competent person can identify hazards and has authority to correct them (Correct answer)
They are interchangeable terms under OSHA
A qualified rigger supervises; a competent person performs the actual rigging
A competent person must hold a state license; a qualified rigger does not

Correct answer: A qualified rigger has recognized training/certification; a competent person can identify hazards and has authority to correct them

OSHA defines a qualified rigger as having demonstrated rigging knowledge/skill, while a competent person has authority to identify and correct hazards — these are distinct roles.

Question 74: What is the most critical output of an effective incident investigation, and why?

Determining whether OSHA standards were violated so citations can be anticipated
Documenting witness statements for litigation purposes
Completing the OSHA 300 Log entry within the required timeframe
A corrective action plan with systemic remedies, assigned owners, and completion dates — because without meaningful systemic changes, incidents will recur (Correct answer)

Correct answer: A corrective action plan with systemic remedies, assigned owners, and completion dates — because without meaningful systemic changes, incidents will recur

The corrective action plan that addresses root causes with specific, trackable actions is the most critical investigation output — without systemic changes, the same hazards will produce future incidents.

Question 75: A safety technician is developing a site emergency action plan. Which communication approach MOST effectively ensures all workers can respond correctly during an actual emergency?

Posting the written plan prominently on the site bulletin board
Emailing the plan to all supervisors for distribution
Conducting regularly scheduled drills that practice emergency procedures (Correct answer)
Including the plan in the new-hire orientation packet

Correct answer: Conducting regularly scheduled drills that practice emergency procedures

Hands-on drills build muscle memory and expose gaps in the plan before a real event. Passive distribution methods (posting, emailing, orientation packets) inform workers but do not develop the conditioned responses needed under stress.

Question 76: Under OSHA 1926.650, what is the definition of an 'excavation'?

Any man-made cut, cavity, trench, or depression in the earth's surface formed by earth removal (Correct answer)
Only cuts in the ground deeper than 4 feet
A trench that is at least as wide as it is deep
Any underground work area where workers are present

Correct answer: Any man-made cut, cavity, trench, or depression in the earth's surface formed by earth removal

OSHA 1926.650 defines an excavation as any man-made cut, cavity, trench, or depression in the earth's surface formed by earth removal, regardless of depth.

Question 77: What is the required minimum height for the top edge of a guardrail system used in construction?

39 inches
48 inches
42 inches (Correct answer)
36 inches

Correct answer: 42 inches

OSHA 1926.502(b)(1) requires the top edge of guardrail systems to be 42 inches plus or minus 3 inches above the walking/working surface.

Question 78: What does the term 'zero energy state' mean in the context of lockout/tagout?

All stored and residual energy has been relieved, disconnected, or restrained so the equipment cannot operate (Correct answer)
The equipment has been unplugged but capacitors may still hold a charge
The circuit breaker is in the off position but not locked
The equipment is running at its lowest power setting

Correct answer: All stored and residual energy has been relieved, disconnected, or restrained so the equipment cannot operate

Zero energy state means all forms of hazardous energy have been controlled so the equipment cannot unexpectedly start or release energy during servicing.

Question 79: What is the purpose of a Hot Work Permit system, and how long must a fire watch remain after hot work is completed?

A Hot Work Permit authorizes and controls spark-producing work in areas where fire hazards exist; a fire watch must remain for at least 30 minutes after hot work ends (Correct answer)
Hot Work Permits are only required when working near sprinkler systems
A Hot Work Permit is only required for cutting torch work; fire watch is not required in open outdoor areas
The fire watch must remain only until the work area has been visually cleared

Correct answer: A Hot Work Permit authorizes and controls spark-producing work in areas where fire hazards exist; a fire watch must remain for at least 30 minutes after hot work ends

Hot Work Permits control fire risks from spark-producing work (welding, cutting, grinding) by requiring hazard assessment, mitigation, and a fire watch for at least 30 minutes after the work ends — since hot surfaces can smolder and ignite hours later.

Question 80: A roofer experiences tingling and numbness in fingers after long-term use of vibrating equipment. This condition is BEST described as:

Carpal tunnel syndrome caused by repetitive flexion
Contact dermatitis from roofing adhesives
Hand-arm vibration syndrome (HAVS) including vascular and neurological effects (Correct answer)
Raynaud's disease unrelated to occupational exposure

Correct answer: Hand-arm vibration syndrome (HAVS) including vascular and neurological effects

Hand-arm vibration syndrome (HAVS) results from prolonged exposure to hand-transmitted vibration, causing both vascular (vibration white finger) and neurological symptoms like tingling and numbness.

Question 81: When must a LOTO periodic inspection be performed, and what must it include?

At least annually; a review of the procedure with each authorized employee (Correct answer)
Before every lockout; verification that locks are functioning properly
Every 5 years; a review of the written procedure only
Every 6 months; retraining all affected employees on energy control

Correct answer: At least annually; a review of the procedure with each authorized employee

OSHA 29 CFR 1910.147(c)(6) requires LOTO procedures to be inspected at least annually and reviewed with each authorized employee who uses the procedure.

Question 82: Under OSHA 1910.38, when must workers be trained on the Emergency Action Plan?

A posted evacuation sign is sufficient as training
At hire, whenever workers' responsibilities change, whenever the EAP is revised, and whenever the employer believes workers have not retained sufficient knowledge (Correct answer)
Annually only
Only for workers designated as fire wardens

Correct answer: At hire, whenever workers' responsibilities change, whenever the EAP is revised, and whenever the employer believes workers have not retained sufficient knowledge

OSHA requires EAP training at initial hire, upon change of responsibilities, when the EAP is updated, and whenever the employer believes workers have not retained sufficient knowledge.

Question 83: A worker is exposed to isocyanate-containing spray foam insulation. What is the MOST serious potential long-term health effect?

Silicosis from polyol filler particles
Lead poisoning from catalyst compounds
Occupational asthma from sensitization (Correct answer)
Carbon monoxide poisoning from off-gassing

Correct answer: Occupational asthma from sensitization

Isocyanates are the leading cause of occupational asthma; once sensitized, a worker can experience severe asthma attacks at even trace concentrations.

Question 84: A worker is found unconscious in a permit-required confined space. What is the FIRST action rescuers should take?

Attempt non-entry rescue using retrieval equipment (Correct answer)
Enter the space immediately to begin CPR
Call 911 and wait for emergency services
Test the atmosphere inside the confined space

Correct answer: Attempt non-entry rescue using retrieval equipment

OSHA requires non-entry rescue to be attempted first using retrieval lines, wristlets, or mechanical systems to avoid endangering the rescuer in a potentially IDLH atmosphere.

Question 85: Which OSHA standard specifically addresses hazard communication requirements, including Safety Data Sheets, on construction sites?

29 CFR 1926.451
29 CFR 1926.501
29 CFR 1926.59 (Correct answer)
29 CFR 1926.651

Correct answer: 29 CFR 1926.59

29 CFR 1926.59 is the Hazard Communication standard for construction, requiring employers to inform workers about chemical hazards through labels, SDSs, and training.

Question 86: An employee slips on ice at the employer's parking lot while walking into work. Under OSHA recordkeeping, this injury is generally:

Not recordable because the parking lot is excluded from the work environment definition (Correct answer)
Recordable only if the employee lost more than one day of work
Recordable because it occurred on employer property
Recordable if the employer failed to apply ice melt

Correct answer: Not recordable because the parking lot is excluded from the work environment definition

OSHA exempts injuries in employer-controlled parking lots, loading docks, and access roads during normal commuting from the definition of the work environment, so such injuries are generally not recordable.

Question 87: What is the primary purpose of a critical lift plan on a construction site?

To eliminate the requirement for a signal person during hoisting operations
To replace the need for a certified crane operator during complex lifts
To document all lifts exceeding 75% of the crane's rated capacity or involving unusual hazards (Correct answer)
To satisfy insurance requirements for general contractor liability

Correct answer: To document all lifts exceeding 75% of the crane's rated capacity or involving unusual hazards

A critical lift plan addresses lifts that approach the crane's capacity limits or involve special hazards, requiring detailed pre-lift engineering and safety analysis.

Question 88: Under OSHA 29 CFR 1926.62, what is the action level for lead exposure that triggers medical surveillance requirements?

10 µg/m³ as an 8-hour TWA
50 µg/m³ as an 8-hour TWA
100 µg/m³ as an 8-hour TWA
30 µg/m³ as an 8-hour TWA (Correct answer)

Correct answer: 30 µg/m³ as an 8-hour TWA

The OSHA action level for lead in construction is 30 µg/m³ as an 8-hour TWA, which requires medical surveillance, biological monitoring, and training.

Question 89: When conducting a Job Hazard Analysis (JHA) for a new construction task, who should be involved in its development?

Only the project safety manager and superintendent
The workers who actually perform the task, along with the supervisor (Correct answer)
Insurance risk manager and project estimator
The project owner's representative and the architect

Correct answer: The workers who actually perform the task, along with the supervisor

Workers performing the task have firsthand knowledge of hazards and practical controls, making their involvement essential to a thorough and realistic JHA.

Question 90: Under 29 CFR 1926.503, employers must verify that each worker who works at heights has been trained by providing which documentation?

Proof of completion of an OSHA 10-hour construction card
A written certification record with the employee's name, training date, and trainer's name (Correct answer)
A copy of the worker's prior employer's fall protection training record
A signed fall protection plan submitted to OSHA before work begins

Correct answer: A written certification record with the employee's name, training date, and trainer's name

29 CFR 1926.503(b) specifically requires a written certification record documenting employee name, training date, and certifying trainer identity.

Question 91: Under OSHA 29 CFR 1926.403, what is the maximum allowable voltage for flexible cords used with portable tools on construction sites without additional overcurrent protection?

240 volts
600 volts with proper insulation rating
120 volts
The standard does not set a voltage limit for flexible cords (Correct answer)

Correct answer: The standard does not set a voltage limit for flexible cords

OSHA 1926.403 addresses conductor use and protection requirements but does not set a specific voltage ceiling for flexible cords; insulation and rating requirements apply based on application.

Question 92: A construction worker develops redness, itching, and blistering after contact with uncured epoxy resin. This reaction is BEST classified as:

Chemical burn
Allergic contact dermatitis (Correct answer)
Irritant contact dermatitis
Photodermatitis

Correct answer: Allergic contact dermatitis

Epoxy resin reactions that involve immune sensitization and occur after repeated exposures are classified as allergic contact dermatitis.

Question 93: Which type of fire extinguisher is appropriate for energized electrical equipment fires on a construction site?

Class B
Class C (Correct answer)
Class D
Class A

Correct answer: Class C

Class C extinguishers use non-conductive agents suitable for energized electrical equipment fires.

Question 94: A construction worker is exposed to a chemical with a vapor pressure of 450 mmHg at 20°C. What does this indicate about the hazard?

The chemical evaporates rapidly and can quickly reach hazardous air concentrations (Correct answer)
The chemical has a very high flash point
The chemical is a solid at room temperature
The chemical has low flammability

Correct answer: The chemical evaporates rapidly and can quickly reach hazardous air concentrations

A high vapor pressure means the chemical evaporates quickly, which can rapidly produce hazardous airborne concentrations in enclosed or poorly ventilated spaces.

Question 95: Under OSHA's Section 11(c) anti-retaliation provisions, an employer is prohibited from taking adverse action against a worker who:

Refuses overtime work citing fatigue
Reports a safety concern or participates in an OSHA inspection (Correct answer)
Files a workers' compensation claim after a recordable injury
Files a grievance with their union about wage disputes

Correct answer: Reports a safety concern or participates in an OSHA inspection

OSH Act Section 11(c) protects workers who report safety or health hazards, refuse to perform work they reasonably believe poses imminent danger, or participate in OSHA inspections. Retaliation for these protected activities is illegal. Workers' comp claims and labor disputes are covered by separate statutes.

Question 96: A CHST is establishing annual safety objectives for a multi-trade construction program. Which approach is MOST consistent with recognized occupational health and safety management system (OHSMS) principles such as ANSI/ASSP Z10 or ISO 45001?

Set objectives using the prior year's Total Recordable Incident Rate (TRIR) as the sole basis
Establish objectives that are measurable, time-bound, and directly address hazards identified through the planning process (Correct answer)
Limit objectives to high-hazard operations only to focus available resources
Carry forward identical objectives from the previous year to maintain program consistency

Correct answer: Establish objectives that are measurable, time-bound, and directly address hazards identified through the planning process

ANSI/ASSP Z10 and ISO 45001 both require that safety objectives be specific, measurable, achievable, relevant, and time-bound (SMART), and that they flow directly from hazard identification and risk assessment findings. Using only lagging indicators like TRIR or recycling prior objectives fails to drive proactive, risk-based improvement.

Question 97: Under OSHA's respiratory protection standard (29 CFR 1910.134), what must be completed before a worker is assigned a respirator?

Completion of a 10-hour OSHA construction course
A written permit signed by the project manager
A written JHA and site safety plan review
Medical evaluation, fit testing, and training (Correct answer)

Correct answer: Medical evaluation, fit testing, and training

Before respirator use, OSHA requires a medical evaluation to confirm the worker can safely wear the respirator, followed by fit testing and training on its proper use.

Question 98: When using a trench box or shield, how far above the surrounding grade must the top of the shield extend?

The shield does not need to extend above grade
At least 6 inches
At least 18 inches (Correct answer)
At least 12 inches

Correct answer: At least 18 inches

Trench shields must extend at least 18 inches above the surrounding grade to provide adequate protection from surface hazards and falling materials.

Question 99: A scaffold board breaks under a worker's weight but the worker grabs a guardrail and is uninjured. This is an example of what type of event, and why should it be investigated?

A property damage event that only requires a maintenance report
An OSHA recordable incident because equipment was damaged
A near miss — it should be investigated because it reveals a hazard that, with a slight difference in circumstances, could have caused serious injury (Correct answer)
A minor incident that does not require investigation since no one was hurt

Correct answer: A near miss — it should be investigated because it reveals a hazard that, with a slight difference in circumstances, could have caused serious injury

A near miss is an unplanned event that did not result in injury but had the potential to do so. Investigating near misses allows hazard correction before a serious injury occurs.

Question 100: What must be done before moving a mobile scaffold?

Lower the platform to its lowest position
Both lower the platform and verify no workers or materials are on it
Check that all casters are unlocked
Ensure no workers or materials are on the scaffold (Correct answer)

Correct answer: Ensure no workers or materials are on the scaffold

All workers and materials must be removed from a mobile scaffold before it is moved to prevent falls.

Question 101: Which analytical method uses a diagram shaped like a fish skeleton to systematically display causes of an incident?

Events and causal factor chart
Ishikawa (fishbone) diagram (Correct answer)
Fault tree analysis
Change analysis

Correct answer: Ishikawa (fishbone) diagram

The Ishikawa or fishbone diagram visually maps cause-and-effect relationships, organizing contributing factors into categories such as personnel, equipment, environment, and procedures.

Question 102: Which class of hard hat provides both impact protection and electrical insulation up to 20,000 volts?

Class C
Class B (Correct answer)
Class E
Class A

Correct answer: Class B

Class B hard hats are designed to protect against impact and penetration from falling objects AND provide electrical insulation rated up to 20,000 volts, making them appropriate for work near high-voltage electrical hazards.

Question 103: During fall protection training, workers should be taught that the total fall distance in a PFAS includes which components?

Free fall distance only
Free fall distance plus deceleration distance only
Deceleration distance plus the height of the anchor above grade
Free fall distance plus deceleration distance plus the worker's height plus a safety margin (Correct answer)

Correct answer: Free fall distance plus deceleration distance plus the worker's height plus a safety margin

Total fall distance includes free fall, deceleration distance, and the worker's height (D-ring to feet), plus a safety factor to ensure the worker does not contact a lower level.

Question 104: A safety technician wants to evaluate whether a newly implemented fall-protection training program is achieving its intended outcomes. Which method provides the MOST objective measure of program effectiveness?

Comparing incident rates and near-miss reports before and after the training rollout (Correct answer)
Surveying workers about their overall satisfaction with the training content
Tracking the number of training hours logged per worker over six months
Counting the number of safety signs and posters added to the site after training

Correct answer: Comparing incident rates and near-miss reports before and after the training rollout

Outcome-based measurement using incident and near-miss data directly links the training intervention to changes in worker behavior and actual safety performance. Training hours, satisfaction surveys, and signage counts are process or perception metrics that do not confirm real risk reduction.

Question 105: When using a tripod and mechanical retrieval system for vertical confined space rescue, the retrieval line must be attached to the entrant's:

Chest harness front D-ring
Wrist D-rings
Full-body harness chest or back D-ring (Correct answer)
Safety belt waist loop

Correct answer: Full-body harness chest or back D-ring

OSHA requires the retrieval line to be attached to the entrant's full-body harness at the chest or back D-ring to allow safe vertical retrieval.

Question 106: Which of the following is required in a written fall protection plan used as an alternative to conventional fall protection methods?

Documentation that conventional methods are infeasible or create a greater hazard (Correct answer)
A list of approved harness manufacturers
A record of all employee medical examinations
Approval from the local building inspector

Correct answer: Documentation that conventional methods are infeasible or create a greater hazard

OSHA 1926.502(k) requires the employer to demonstrate that conventional fall protection is infeasible or creates a greater hazard before using alternative measures.

Question 107: Under OSHA's LOTO standard 1910.147, what must be done if a piece of equipment cannot be locked out because it has no provision for a lock?

Verbal notification to affected workers is sufficient
A supervisor must be present at all times during the work
A tagout device must be used along with additional safety measures to provide protection equivalent to lockout (Correct answer)
The work cannot proceed until the equipment is retrofitted with a hasp

Correct answer: A tagout device must be used along with additional safety measures to provide protection equivalent to lockout

When a lockout device cannot be applied, a tagout device must be used and additional measures must be taken to provide a level of safety equivalent to lockout, such as removing a valve handle or blocking a switch.

Question 108: Which of the following DOES NOT, in general, meet NIOSH's definition of a hazard control strategy for preventing work-related injuries?

Administrative controls
Adherence to the Fair Labor Standards Act (FLSA) (Correct answer)
Personal protective equipment
Engineering controls

Correct answer: Adherence to the Fair Labor Standards Act (FLSA)

The hierarchy of controls, which recommends using engineering controls, administrative controls, and personal protective equipment in the workplace in that order to prevent work-related injuries, is encouraged by NIOSH.

Question 109: Which OSHA standard requires employers in general industry to report an in-patient hospitalization of one or more employees within 24 hours?

29 CFR 1904.39 (Correct answer)
29 CFR 1904.4
29 CFR 1926.21
29 CFR 1910.132

Correct answer: 29 CFR 1904.39

29 CFR 1904.39 mandates that employers report work-related in-patient hospitalizations, amputations, and losses of an eye to OSHA within 24 hours.

Question 110: During a pre-task planning (PTP) meeting, workers identify a trench excavation that may have unstable soil. The FIRST action should be to:

Proceed carefully and monitor the trench walls during digging
Stop work and assess soil classification before excavation begins (Correct answer)
Notify OSHA immediately before doing anything else
Request a written variance from the project owner

Correct answer: Stop work and assess soil classification before excavation begins

OSHA 29 CFR 1926 Subpart P requires soil classification before selecting an excavation protective system; work must not begin until this is determined.

Question 111: During a pre-task safety briefing, a foreman should address which item FIRST?

Identify the hazards associated with the planned work activity (Correct answer)
Review the specific OSHA standard numbers applicable to the work
Assign PPE requirements to each worker based on job role
Complete all required JHA and permit paperwork before speaking

Correct answer: Identify the hazards associated with the planned work activity

Hazard identification is the foundation of any pre-task safety communication. Knowing what can go wrong drives all subsequent decisions—PPE selection, control measures, and permit requirements all flow from understanding the hazards present.

Question 112: Under the OSHA Heat Illness Prevention guidance, which physiological sign indicates heat stroke rather than heat exhaustion?

Altered mental status and hot, dry or wet skin (Correct answer)
Nausea and headache with normal mentation
Muscle cramps and weakness
Heavy sweating and pale, moist skin

Correct answer: Altered mental status and hot, dry or wet skin

Heat stroke, a medical emergency, is distinguished by central nervous system dysfunction (confusion, altered consciousness) and core body temperature above 104°F (40°C).

Question 113: According to OSHA 29 CFR 1926.503, fall protection training for construction workers must be conducted by:

A competent person qualified in fall protection (Correct answer)
The general contractor's HR department
Any experienced co-worker on the crew
A third-party OSHA-authorized trainer only

Correct answer: A competent person qualified in fall protection

OSHA 1926.503 requires that fall protection training be provided by a competent person with knowledge and ability in the subject.

Question 114: What is the primary purpose of a Job Hazard Analysis (JHA)?

To assign blame after an incident occurs
To train new employees on company policies
To satisfy OSHA recordkeeping requirements
To identify hazards before a task begins and establish controls (Correct answer)

Correct answer: To identify hazards before a task begins and establish controls

A JHA proactively identifies hazards associated with specific job tasks so controls can be implemented before work starts.

Question 115: What is the maximum noise exposure allowed by OSHA for an 8-hour workday without hearing protection?

85 dBA
95 dBA
80 dBA
90 dBA (Correct answer)

Correct answer: 90 dBA

OSHA's permissible exposure limit (PEL) for noise is 90 dBA as an 8-hour time-weighted average (TWA) under 29 CFR 1926.52.

Question 116: When using the 5 Whys technique during a construction incident investigation, what indicates that the root cause has been reached?

When the answer points to a process or system failure that can be corrected (Correct answer)
When a worker's unsafe act is identified
When exactly five questions have been asked
When the investigator runs out of questions to ask

Correct answer: When the answer points to a process or system failure that can be corrected

The root cause is reached when the answer identifies a process or system failure that management can address with corrective actions, regardless of how many questions were asked.

Question 117: What is the purpose of an anti-two-block device on a crane?

To prevent the hook block from contacting the boom tip, which could cause the load line to fail (Correct answer)
To limit the crane's maximum travel speed on the jobsite
To automatically level the crane on uneven terrain
To lock the swing brake when the operator leaves the cab

Correct answer: To prevent the hook block from contacting the boom tip, which could cause the load line to fail

An anti-two-block device warns or stops the hoist when the hook block approaches the boom tip, preventing a two-block condition that could sever the wire rope and drop the load.

Question 118: During confined-space entry on a construction site, the atmosphere tests at 19.0% oxygen. How should this be classified?

Slightly low — a half-face APR with OV cartridge is sufficient
Oxygen-deficient — entry requires supplied-air or SCBA (Correct answer)
Normal — no action required since it is close to 20.9%
Oxygen-enriched — fire risk is the primary concern

Correct answer: Oxygen-deficient — entry requires supplied-air or SCBA

OSHA defines an oxygen-deficient atmosphere as less than 19.5% O₂; at 19.0% the space requires supplied-air or SCBA for entry.

Question 119: What is the maximum permissible noise exposure level for an 8-hour time-weighted average under OSHA construction standards?

90 dBA (Correct answer)
80 dBA
95 dBA
85 dBA

Correct answer: 90 dBA

OSHA's construction noise standard (29 CFR 1926.52) sets the permissible exposure limit at 90 dBA for an 8-hour TWA.

Question 120: Under OSHA's General Duty Clause (Section 5(a)(1) of the OSH Act), what four elements must OSHA prove to issue a citation?

Workers were injured; OSHA investigated; the employer was cited; the employer had no written safety program
The employer failed to keep the workplace free of a hazard; the hazard was recognized; the hazard was causing or likely to cause death or serious physical harm; and a feasible means to correct the hazard existed (Correct answer)
The employer violated a specific OSHA standard; workers were exposed; the employer knew of the violation; penalties were calculated
The employer had prior OSHA citations; workers were exposed; the hazard was recognized; the employer refused to correct it

Correct answer: The employer failed to keep the workplace free of a hazard; the hazard was recognized; the hazard was causing or likely to cause death or serious physical harm; and a feasible means to correct the hazard existed

To cite under the General Duty Clause, OSHA must prove four elements: the employer failed to keep the workplace free of a hazard; the hazard was recognized; the hazard was causing or likely to cause death or serious physical harm; and a feasible correction existed.

Question 121: Which of the following is the maximum asbestos fiber concentration for an eight-hour exposure allowed by 29 CFR 1926.1101?

10 fibers per cubic centimeter of air
0.25 fibers per cubic centimeter of air
0.1 fibers per cubic centimeter of air (Correct answer)
100 fibers per cubic centimeter of air

Correct answer: 0.1 fibers per cubic centimeter of air

According to 29 CFR 1926.1101, an employer is required to make sure that no employee is exposed to more than 0.1 fibers of asbestos per cubic centimeter of air over the course of an eight-hour shift.

Question 122: A CHST conducting a job hazard analysis (JHA) for concrete formwork discovers workers may be exposed to silica dust. Which OSHA standard primarily governs silica exposure in construction?

29 CFR 1926.62
29 CFR 1926.1153 (Correct answer)
29 CFR 1926.55
29 CFR 1926.200

Correct answer: 29 CFR 1926.1153

29 CFR 1926.1153 is OSHA's Respirable Crystalline Silica Standard for construction, establishing PELs and required controls.

Question 123: Under OSHA's Hazard Communication Standard, what information must appear on the inner container label of a hazardous chemical?

Product identifier, signal word, hazard pictograms, precautionary statements, and supplier information (Correct answer)
Product identifier and GHS hazard class number only
Only the product identifier
Safety Data Sheet number and emergency contact only

Correct answer: Product identifier, signal word, hazard pictograms, precautionary statements, and supplier information

GHS-aligned labels must include the product identifier, signal word, hazard pictograms, hazard statements, precautionary statements, and supplier identification.

Question 124: A contractor must manage a scope change that introduces new chemical exposures on-site. What is the FIRST action the safety technician should take?

Obtain and review SDSs for the new chemicals (Correct answer)
Order appropriate PPE for the anticipated chemicals
Notify OSHA of the change in scope via their online portal
Update the site's emergency response plan

Correct answer: Obtain and review SDSs for the new chemicals

Reviewing SDSs first provides the hazard information needed to determine appropriate controls, PPE, and emergency measures.

Question 125: Under OSHA 1926.102, eye and face protection must meet which ANSI standard for impact resistance?

ANSI Z89.1
ANSI Z87.3
ANSI Z87.1 (Correct answer)
ANSI Z41.1

Correct answer: ANSI Z87.1

OSHA 1926.102(a)(1) requires that eye and face protection devices meet ANSI Z87.1, which establishes performance requirements for impact, optical quality, and other properties of safety eyewear.

Question 126: Which of the following best describes the primary role of communication in an effective Emergency Action Plan (EAP) on a construction site?

To document the emergency for insurance and liability purposes only.
To inform the media about the status of an ongoing emergency.
To assign blame after an incident has been resolved.
To ensure all employees understand their roles and responsibilities during an emergency. (Correct answer)

Correct answer: To ensure all employees understand their roles and responsibilities during an emergency.

Effective communication is crucial for an Emergency Action Plan. According to OSHA standard 29 CFR 1926.35, the plan must be reviewed with each employee. This communication ensures that everyone knows how to report emergencies, what their specific duties are (e.g., evacuation, operating fire extinguishers), and how to exit safely, which is essential for protecting lives.

Question 127: What is the recommended frequency for conducting toolbox talks on an active construction site?

Only when OSHA conducts an inspection
Weekly or before each new task/phase of work (Correct answer)
Monthly during all-hands safety meetings
Quarterly as part of the project safety audit

Correct answer: Weekly or before each new task/phase of work

Toolbox talks should be conducted at least weekly or whenever a new task or phase of work begins to address current and emerging hazards relevant to the crew's activities.

Question 128: What is the OSHA permissible exposure limit (PEL) for respirable crystalline silica in construction?

0.1 mg/m³ as an 8-hour TWA
0.025 mg/m³ as an 8-hour TWA (Correct answer)
0.05 mg/m³ as an 8-hour TWA
0.25 mg/m³ as an 8-hour TWA

Correct answer: 0.025 mg/m³ as an 8-hour TWA

OSHA's silica standard for construction (29 CFR 1926.1153) sets the PEL at 50 micrograms per cubic meter (0.025 mg/m³ respirable) as an 8-hour TWA.

Question 129: Which of the following best describes the purpose of a Job Safety Analysis (JSA) in construction safety management?

To document injuries after they occur for OSHA recordkeeping
To fulfill OSHA's required written program for confined spaces
To identify, analyze, and control hazards associated with specific job steps before work begins (Correct answer)
To measure a worker's compliance with PPE requirements

Correct answer: To identify, analyze, and control hazards associated with specific job steps before work begins

A JSA proactively breaks a job into steps, identifies hazards associated with each step, and establishes controls before work begins.

Question 130: What is the PRIMARY purpose of conducting a post-incident critique or after-action review immediately following a significant construction incident?

Satisfy insurance carrier documentation requirements
Calculate workers' compensation cost impact
Capture time-sensitive information and identify immediate corrective actions (Correct answer)
Assign disciplinary action to responsible workers

Correct answer: Capture time-sensitive information and identify immediate corrective actions

Post-incident critiques conducted quickly preserve fresh witness recollections and physical evidence, enabling prompt identification and implementation of corrective actions.

Question 131: A 'competent person' in OSHA construction standards is defined as someone who can:

Identify hazardous conditions and has authority to correct them (Correct answer)
Perform tasks without supervision
Approve safety plans on behalf of OSHA
Certify workers are trained

Correct answer: Identify hazardous conditions and has authority to correct them

OSHA defines a competent person as one who is capable of identifying existing and predictable hazardous conditions and has authorization to take corrective measures.

Question 132: A construction worker is tasked with installing a safety net system. Which of the following installation requirements is NOT compliant with OSHA standards?

The mesh openings of the net do not exceed 6 inches by 6 inches.
The net is drop-tested with a 200-pound bag of sand before use. (Correct answer)
The border rope of the net has a minimum breaking strength of 5,000 pounds.
The net is installed no more than 30 feet below the working surface.

Correct answer: The net is drop-tested with a 200-pound bag of sand before use.

OSHA 1926.502(c) specifies that safety nets must be drop-tested with a 400-pound bag of sand, not 200 pounds. The other options are all correct requirements for safety net systems: they must be installed as close as practicable but no more than 30 feet below the work surface, have mesh openings no larger than 6x6 inches, and have a border rope with a minimum breaking strength of 5,000 pounds.

Question 133: Which biological health hazard should a CHST be most concerned about when workers disturb bird or bat droppings during building renovation?

Histoplasma capsulatum (Correct answer)
Legionella pneumophila
Staphylococcus aureus
Escherichia coli

Correct answer: Histoplasma capsulatum

Histoplasma capsulatum is a fungus found in soil enriched with bird or bat droppings, and inhaling disturbed spores can cause histoplasmosis, a serious respiratory infection.

Question 134: What is the maximum allowable side pull angle for a standard single-part wire rope sling lift?

10 degrees
15 degrees
30 degrees
5 degrees (Correct answer)

Correct answer: 5 degrees

ASME B30.9 recommends keeping side pull to a minimum; crane manufacturers typically prohibit side loading beyond 5 degrees because it induces lateral boom stress.

Question 135: Three characteristics that define a 'confined space' under OSHA include all of the following EXCEPT:

Large enough for an employee to bodily enter and perform work
Not designed for continuous employee occupancy
Limited or restricted means for entry or exit
Contains electrical or mechanical hazards (Correct answer)

Correct answer: Contains electrical or mechanical hazards

The three OSHA defining characteristics of a confined space are: large enough to enter and work in, limited entry/exit, and not designed for continuous occupancy—electrical hazards describe a hazard type, not a defining characteristic.

Question 136: Which class of fire extinguisher is specifically designed to fight fires involving energized electrical equipment on a construction site?

Class C (Correct answer)
Class D
Class A
Class B

Correct answer: Class C

Class C extinguishers use non-conductive agents and are rated for energized electrical equipment fires.

Question 137: A worker is assigned to a task where the airborne concentration of a hazardous substance is 400 µg/m³. The Permissible Exposure Limit (PEL) for this substance is 50 µg/m³. The worker is provided with a half-mask air-purifying respirator. What is the minimum Assigned Protection Factor (APF) required, and does the provided respirator meet this requirement?

APF 10; No, a higher level of protection is needed.
APF 8; Yes, the respirator is adequate.
APF 5; Yes, the respirator is adequate.
APF 10; Yes, the respirator is adequate. (Correct answer)

Correct answer: APF 10; Yes, the respirator is adequate.

The required APF is calculated by dividing the measured concentration by the PEL: 400 µg/m³ / 50 µg/m³ = 8. Therefore, a respirator with an APF of at least 8 is required. According to OSHA, a half-mask air-purifying respirator has an APF of 10. Since 10 is greater than the required 8, the respirator is adequate for the task.

Question 138: During a safety audit, an inspector finds workers using extension ladders without securing the top or bottom. What immediate corrective action is required?

Tag the ladder out of service and notify OSHA
Stop the work and secure the ladder before allowing use to continue (Correct answer)
Issue a verbal warning and document the finding
Replace the extension ladder with a step ladder

Correct answer: Stop the work and secure the ladder before allowing use to continue

An unsecured ladder is an immediate hazard requiring work stoppage until the ladder is properly secured to prevent slipping or falling.

Question 139: A safety technician is reviewing incident records and calculates a Days Away, Restricted, or Transferred (DART) rate of 4.5. How is this rate expressed?

Per 1,000,000 hours worked
Per 200,000 hours worked (Correct answer)
Per 100 workers per year
Per 50 employees

Correct answer: Per 200,000 hours worked

OSHA injury/illness rates including DART are calculated per 200,000 hours worked, which represents 100 full-time equivalent employees working one year.

Question 140: Under OSHA 1910.147, what is required before an authorized employee may restore energy to equipment after LOTO servicing is complete?

The supervisor removes the lockout device on behalf of the crew
One authorized employee removes all locks and notifies the others
All tools and materials removed, all workers clear of the machine, and all LOTO devices removed by the employees who applied them before the energy-isolating device is operated (Correct answer)
The safety officer certifies the repair is complete in writing

Correct answer: All tools and materials removed, all workers clear of the machine, and all LOTO devices removed by the employees who applied them before the energy-isolating device is operated

Before restoring energy, all nonessential items must be removed, all workers must be clear and notified, and each employee must remove their own lockout device before the energy-isolating device is operated.

Question 141: Under OSHA's Lockout/Tagout standard (29 CFR 1910.147), what must an authorized employee do AFTER applying a lockout device before performing service or maintenance?

Notify all affected employees verbally
Obtain written approval from the site superintendent
Install a secondary tagout device on the energy source
Verify that the equipment is de-energized by attempting normal operation or using a test instrument (Correct answer)

Correct answer: Verify that the equipment is de-energized by attempting normal operation or using a test instrument

After applying lockout/tagout devices and releasing or restraining stored energy, the authorized employee must verify isolation by attempting to operate the equipment using normal controls or by using a test instrument to confirm that hazardous energy has been de-energized.

Question 142: What does OSHA 1926.20 'General Safety and Health Provisions' require of all construction employers?

Employers must initiate and maintain safety programs, provide frequent and regular inspections by competent persons, and comply with all applicable standards in Part 1926 (Correct answer)
It is an optional guideline for large contractors only
It solely addresses recordkeeping and reporting requirements
It only applies to federal construction projects

Correct answer: Employers must initiate and maintain safety programs, provide frequent and regular inspections by competent persons, and comply with all applicable standards in Part 1926

OSHA 1926.20 establishes baseline obligations for all construction employers: maintenance of a safety program, appointment of competent persons, frequency of inspections, and compliance with all applicable Part 1926 standards.

Question 143: What is the minimum tensile strength required for lifelines used in personal fall arrest systems under OSHA 1926.502?

5,000 pounds (Correct answer)
4,000 pounds
3,000 pounds
2,500 pounds

Correct answer: 5,000 pounds

OSHA requires lifelines to have a minimum breaking strength of 5,000 pounds.

Question 144: What does the acronym PASS stand for when using a portable fire extinguisher?

Pull the pin, Aim at the base of the fire, Squeeze the handle, Sweep side to side (Correct answer)
Point at the flames, Aim high, Squeeze trigger, Spray continuously
Pull pin, Apply pressure, Stand back, Spray at the top
Press handle, Aim at center, Squeeze trigger, Sweep upward

Correct answer: Pull the pin, Aim at the base of the fire, Squeeze the handle, Sweep side to side

PASS stands for Pull the pin, Aim the nozzle at the base of the fire (not the flames), Squeeze the handle to discharge the agent, and Sweep the nozzle side to side at the base of the fire.

Question 145: What is the minimum tensile strength required for each lanyard or vertical lifeline in a personal fall arrest system?

7,500 pounds
10,000 pounds
5,000 pounds (Correct answer)
3,000 pounds

Correct answer: 5,000 pounds

OSHA 1926.502(d)(9) requires that lanyards and vertical lifelines have a minimum breaking strength of 5,000 pounds.

Question 146: What is the main advantage of using scenario-based simulations (e.g., tabletop exercises) in construction emergency response training?

They allow workers to practice decision-making in a risk-free environment before a real emergency (Correct answer)
They satisfy all OSHA-required emergency drills for the year
They are faster to deliver than traditional classroom instruction
They eliminate the need for written emergency action plans

Correct answer: They allow workers to practice decision-making in a risk-free environment before a real emergency

Simulation exercises build muscle memory and decision-making skills under simulated stress without real-life consequences of error.

Question 147: When conducting interviews with witnesses after an incident, which of the following is a key principle for the investigator to follow?

Ask leading questions to confirm the initial theory of what happened.
Focus on discovering who was at fault to ensure accountability.
Ask open-ended questions in a private, non-threatening setting. (Correct answer)
Interview all witnesses in a group to establish a consensus timeline.

Correct answer: Ask open-ended questions in a private, non-threatening setting.

Effective witness interviewing requires creating a comfortable environment where the witness feels safe to share information. Asking open-ended questions (e.g., "Tell me what you saw") in a private setting encourages a detailed, unbiased narrative. Group interviews can lead to peer pressure, leading questions can bias the answer, and focusing on blame discourages cooperation and can obscure the true root causes.

Question 148: When performing a Job Hazard Analysis (JHA) for emergency scenarios, which element is most critical to address for multi-story construction projects?

Proximity of the nearest hospital
Vertical evacuation routes and stairwell integrity (Correct answer)
Noise levels during evacuation
Color coding of emergency signs

Correct answer: Vertical evacuation routes and stairwell integrity

Multi-story construction requires specific attention to safe vertical evacuation paths since elevators cannot be used during fires.

Question 149: What is the correct soil classification for a trench in soil that is granular (sand), submerged, and has water freely seeping through it?

Type C — the least stable classification (Correct answer)
Stable Rock — no classification needed
Type A — cohesive and stable
Type B — medium stability

Correct answer: Type C — the least stable classification

Submerged granular soil with free water seepage meets the definition of Type C soil, the least stable classification requiring the most conservative protective system.

Question 150: What is the action level for lead exposure in construction that triggers medical surveillance requirements?

50 µg/m³ as an 8-hr TWA
30 µg/m³ as an 8-hr TWA (Correct answer)
10 µg/m³ as an 8-hr TWA
100 µg/m³ as an 8-hr TWA

Correct answer: 30 µg/m³ as an 8-hr TWA

An action level of 30 µg/m³ as an 8-hour TWA triggers medical surveillance requirements under OSHA's construction lead standard.

Question 151: What should be the first action of a construction worker who discovers a fire that cannot be immediately controlled with a portable extinguisher?

Activate the fire alarm and evacuate the area (Correct answer)
Continue working and monitor the fire
Attempt to fight the fire with available materials
Search for a larger extinguisher

Correct answer: Activate the fire alarm and evacuate the area

When a fire cannot be immediately controlled, the priority is to alert others by activating the alarm and evacuating to prevent injuries.

Question 152: Which factor does NOT affect a crane's rated load capacity?

Boom angle
Boom length
Wind speed
Operator's years of experience (Correct answer)

Correct answer: Operator's years of experience

Rated capacity is a mechanical/structural calculation based on boom angle, length, and configuration — operator experience is not a variable in the load chart.

Question 153: Under ANSI/ASSP Z10, which element is considered foundational to an occupational health and safety management system?

Incident investigation procedures
Emergency response planning
Personal protective equipment programs
Management leadership and employee participation (Correct answer)

Correct answer: Management leadership and employee participation

ANSI/ASSP Z10 identifies management leadership and employee participation as the foundational element upon which all other safety management system components are built.

Question 154: When conducting a Site-level MSD risk assessment, the SAFETY technician should prioritize which data source first?

Published industry MSD incidence rates for comparable construction trades
Worker symptom surveys and near-miss reports from the affected crews (Correct answer)
OSHA 300 log entries for musculoskeletal injuries and disorders
Workers' compensation claim costs by department

Correct answer: Worker symptom surveys and near-miss reports from the affected crews

Worker symptom surveys and near-miss reports capture early-stage discomfort before it becomes a recordable injury, enabling proactive intervention. OSHA 300 logs and WC data are lagging indicators — they record harm already done. Industry benchmarks reflect average conditions, not site-specific exposures.

Question 155: What is the minimum number of emergency telephone numbers that must be posted at a construction site job site per OSHA requirements under 29 CFR 1926.35?

No specific number required, but the EAP must define notification methods (Correct answer)
One (911 only)
Three (fire, ambulance, police)
Two

Correct answer: No specific number required, but the EAP must define notification methods

OSHA 1926.35 requires an EAP to include notification methods but does not specify a minimum count of posted numbers; the plan must define the procedures.

Question 156: Which type of fire extinguisher is most appropriate for a Class D (combustible metal) fire at a construction site?

Dry chemical (ABC)
Dry sand or Met-L-X powder (Correct answer)
CO2 (Class B/C)
Water (Class A)

Correct answer: Dry sand or Met-L-X powder

Class D fires involving combustible metals like magnesium require specialized dry powder agents such as Met-L-X, not standard extinguishers.

Question 157: Which of the following best describes the purpose of a pre-task safety briefing (toolbox talk) on a construction site?

To document workers' compensation claims
To fulfill the annual OSHA training requirement
To review specific hazards and safe work practices for the day's tasks (Correct answer)
To assign personal protective equipment for the entire project

Correct answer: To review specific hazards and safe work practices for the day's tasks

Pre-task safety briefings address the specific hazards and controls relevant to the work being performed that day, keeping safety awareness current.

Question 158: A rigger notices that a wire rope sling has a kink that cannot be straightened. What should the rigger do?

Straighten the kink using a pipe for leverage
Continue use if the kink is not at the choker point
Tag and remove the sling from service (Correct answer)
Use the sling at reduced capacity

Correct answer: Tag and remove the sling from service

A kinked wire rope sling is permanently damaged and weakened; it must be removed from service and destroyed.

Question 159: A competent person inspects a personal fall arrest system after an employee experiences a fall. What action is required?

The system must be removed from service immediately (Correct answer)
The system may be reused after visual inspection
The system can be reused if the lanyard shows no visible damage
The system needs re-inspection within 30 days

Correct answer: The system must be removed from service immediately

OSHA 1926.502(d)(21) requires that fall arrest equipment subjected to impact loading be immediately removed from service.

Question 160: A construction crew is using a 120-volt portable generator to power cord-and-plug tools on a job site. To best protect workers from electric shock, the receptacles on the generator should be protected by a:

Ground-fault circuit-interrupter (GFCI) (Correct answer)
Double-insulated housing
Fuse rated for the tool's amperage
Surge protector

Correct answer: Ground-fault circuit-interrupter (GFCI)

OSHA 29 CFR 1926.404(b)(1) requires that all 120-volt, single-phase, 15- and 20-ampere receptacle outlets on construction sites, which are not part of the permanent wiring, be protected by ground-fault circuit-interrupters (GFCIs). GFCIs are essential for shock protection with portable equipment where grounding may be compromised.

Question 161: What is the primary purpose of a fire watch during hot work operations?

To document the work being performed
To ensure ventilation equipment is functioning
To verify the welder's credentials
To monitor for ignition of fires during and after hot work (Correct answer)

Correct answer: To monitor for ignition of fires during and after hot work

A fire watch is maintained during and for at least 30 minutes after hot work to detect and extinguish any fires that may ignite from sparks or heat.

Question 162: According to OSHA's Hazard Communication Standard (HazCom 2012), what must be readily accessible to construction workers who handle hazardous chemicals on site?

The site supervisor's emergency contact information
The chemical manufacturer's phone number only
A first aid kit with chemical antidotes
Safety Data Sheets for all hazardous chemicals present (Correct answer)

Correct answer: Safety Data Sheets for all hazardous chemicals present

OSHA's HazCom standard requires that Safety Data Sheets be readily accessible to all employees who may be exposed to hazardous chemicals during their work shift.

Question 163: Which type of fire extinguisher is appropriate for Class C (electrical) fires?

Water-based extinguisher
Wet chemical extinguisher
Class K extinguisher
CO2 or dry chemical extinguisher (Correct answer)

Correct answer: CO2 or dry chemical extinguisher

CO2 and dry chemical extinguishers are rated for Class C fires because they use non-conductive agents; water conducts electricity and must never be used on electrical fires.

Question 164: Which type of glove material provides the BEST protection against ketone solvents commonly found on construction sites?

Latex rubber
Natural rubber
Polyvinyl chloride (PVC)
Butyl rubber (Correct answer)

Correct answer: Butyl rubber

Butyl rubber gloves offer superior resistance to ketones and other polar solvents, outperforming latex, natural rubber, and PVC for these chemicals.

Question 165: A group lockout/tagout procedure is being used on a construction project. What is the primary responsibility of the authorized employee in charge?

Ensuring that all members of the group are protected throughout the lockout and coordinating the application and removal of lockout devices (Correct answer)
Scheduling the maintenance window with the client
Purchasing the correct locks for the crew
Training new employees on general site safety

Correct answer: Ensuring that all members of the group are protected throughout the lockout and coordinating the application and removal of lockout devices

The authorized employee in charge of a group lockout must ensure continuity of protection for all workers and coordinate the overall lockout/tagout effort.

Question 166: Under OSHA 1926.416, what minimum clearance must be maintained from overhead energized power lines rated at 50 kV or below when using equipment on a construction site?

20 feet
10 feet (Correct answer)
15 feet
6 feet

Correct answer: 10 feet

OSHA 1926.416(a)(1) and OSHA 1926.600 require a minimum clearance of 10 feet from any part of a tool, equipment, or machinery to overhead power lines rated at 50 kV or less.

Question 167: Under OSHA recordkeeping requirements, which of the following incidents must be reported to OSHA within 8 hours?

A work-related amputation
A work-related fatality (Correct answer)
A work-related loss of an eye
Any workplace injury requiring first aid

Correct answer: A work-related fatality

OSHA requires employers to report any work-related fatality within 8 hours, while amputations, loss of an eye, and inpatient hospitalizations must be reported within 24 hours.

Question 168: A general contractor is planning to introduce a new type of concrete formwork system that workers have never used before. Under a formal safety management system, which program management step should occur FIRST?

Initiate a Management of Change (MOC) review before the equipment arrives on site (Correct answer)
Update the OSHA 300 log to reflect potential new hazard categories
Revise the site emergency action plan once the equipment is installed
Add the formwork system to the next scheduled toolbox talk agenda

Correct answer: Initiate a Management of Change (MOC) review before the equipment arrives on site

Management of Change (MOC) is a structured process that evaluates new hazards introduced by changes in equipment, materials, or processes before the change is implemented. Waiting until the equipment arrives or relying solely on a toolbox talk bypasses the proactive hazard identification the MOC process is designed to provide.

Question 169: During a lockout/tagout procedure, who is authorized to remove a lock placed by another worker?

Any qualified electrician on the crew
Only the worker who applied the lock, with limited exceptions under employer procedures (Correct answer)
The site superintendent
The general contractor's safety manager

Correct answer: Only the worker who applied the lock, with limited exceptions under employer procedures

OSHA requires that only the employee who applied the lock may remove it, except under specific documented employer procedures when that worker is unavailable.

Question 170: During a CHST incident investigation, a witness refuses to provide a written statement. The BEST approach is to:

Terminate the investigation until the witness complies
Assume the witness is at fault and proceed accordingly
Report the witness to OSHA for non-cooperation
Document the refusal and interview other witnesses while noting the gap (Correct answer)

Correct answer: Document the refusal and interview other witnesses while noting the gap

Investigators should document a witness's refusal, continue gathering information from available sources, and note the evidentiary gap without drawing unwarranted conclusions.

Question 171: A safety net must be installed as close as practicable to the work surface and never more than how many feet below the working level?

25 feet
15 feet
30 feet (Correct answer)
20 feet

Correct answer: 30 feet

OSHA 1926.502(c) requires safety nets to be installed no more than 30 feet below the working surface.

Question 172: What is the primary purpose of the 'noise reduction rating' (NRR) labeled on hearing protection devices?

To certify the device for use in confined space noise environments only
To allow employers to estimate the degree of noise attenuation in the field (Correct answer)
To specify the maximum continuous exposure duration for the device
To indicate the device's frequency cutoff for low-frequency noise

Correct answer: To allow employers to estimate the degree of noise attenuation in the field

The NRR is an EPA-standardized laboratory rating used to estimate field attenuation. OSHA instructs employers to derate the NRR by 50% (for earmuffs) or up to 70% (for formable earplugs) to account for real-world fit variability, giving a realistic estimate of protected exposure.

Question 173: When performing a root cause analysis after an incident, which tool is BEST suited for systematically identifying contributing causes by asking 'why' repeatedly?

Scatter diagram
5 Whys technique (Correct answer)
Pareto chart
Fault tree analysis

Correct answer: 5 Whys technique

The 5 Whys technique involves asking 'why' up to five times to drill down from the symptom of a problem to its root cause.

Question 174: What is the OSHA permissible exposure limit (PEL) for benzene in construction as an 8-hour TWA?

1 ppm (Correct answer)
5 ppm
10 ppm
0.5 ppm

Correct answer: 1 ppm

OSHA's PEL for benzene is 1 ppm as an 8-hour TWA (29 CFR 1910.1028, adopted by construction), with an action level of 0.5 ppm.

Question 175: A safety net system must be installed no more than how many feet below the working surface per OSHA 1926.502(c)?

25 feet
30 feet (Correct answer)
20 feet
15 feet

Correct answer: 30 feet

OSHA 1926.502(c)(1) requires safety nets to be installed as close as practicable to the working surface but no more than 30 feet below to limit fall distance and ensure effective arrest.

Question 176: Under OSHA 1926.651(h), how must water accumulation in an excavation be controlled?

Workers may work in accumulated water as long as they wear rubber boots
Water must be removed by pumping or diverting, and work must stop when water accumulates to hazardous levels until the competent person determines it is safe to proceed (Correct answer)
Pumping is required only when water depth exceeds 12 inches
Standing water is acceptable in Type A soil

Correct answer: Water must be removed by pumping or diverting, and work must stop when water accumulates to hazardous levels until the competent person determines it is safe to proceed

OSHA 1926.651(h) requires that surface water or water run-off be controlled, that workers not work in accumulated water unless adequate precautions are taken, and that all water control measures be directed by the competent person.

Question 177: A safety technician calculates the required attenuation for hearing protection in an area with an A-weighted Time-Weighted Average (TWA) noise exposure of 102 dBA. The company policy is to use OSHA's standard formula for estimating workplace protection. If a worker uses earplugs with a Noise Reduction Rating (NRR) of 33, what is the estimated exposure in dBA under the protector?

76 dBA (Correct answer)
69 dBA
70 dBA
84 dBA

Correct answer: 76 dBA

OSHA's formula for estimating the protected A-weighted TWA from an A-weighted measurement is to subtract 7 from the NRR, and then subtract the result from the measured TWA. Calculation: NRR 33 - 7 = 26. Then, 102 dBA - 26 = 76 dBA. This estimated exposure is below the OSHA Permissible Exposure Limit (PEL) of 90 dBA and the action level of 85 dBA.

Question 178: What is the primary health concern when construction workers are exposed to hydrogen sulfide (H2S) gas in sewer line excavation work?

Olfactory fatigue leading to undetected lethal exposure (Correct answer)
Skin irritation and chemical burns
Permanent hearing loss
Chronic liver damage

Correct answer: Olfactory fatigue leading to undetected lethal exposure

Hydrogen sulfide causes olfactory fatigue at higher concentrations, meaning workers lose the ability to smell the gas and may be unknowingly exposed to lethal levels.

Question 179: As the angle between two sling legs increases (the legs spread farther apart), what happens to the tension in each sling leg for the same load?

Tension stays constant regardless of angle
Tension in each leg decreases as the angle increases
Tension only changes when the angle exceeds 90 degrees
Tension in each leg increases as the angle between the legs increases (Correct answer)

Correct answer: Tension in each leg increases as the angle between the legs increases

As the sling angle (measured from horizontal) decreases or the included angle between legs increases, sling leg tension increases dramatically due to force vector geometry — this is known as the sling angle factor.

Question 180: When is a registered professional engineer (PE) required to design a protective system for an excavation?

Any trench in Type B soil
When more than 5 workers are in the trench
Any excavation deeper than 4 feet
Tabulated data or manufacturer data is not available for the site conditions (Correct answer)

Correct answer: Tabulated data or manufacturer data is not available for the site conditions

A PE-designed system is required when site conditions fall outside the scope of OSHA Appendix tables or manufacturer-supplied tabulated data under 29 CFR 1926.652(b)(4).

Question 181: Under OSHA's Lockout/Tagout standard (29 CFR 1910.147), who is generally the only person authorized to remove a lock or tag from an energy isolating device?

The competent person for the jobsite.
The employee who initially applied the lock or tag. (Correct answer)
Any qualified electrician on site.
The site supervisor for the work crew.

Correct answer: The employee who initially applied the lock or tag.

OSHA standard 29 CFR 1910.147(e)(3) is very clear that the lock and tag must be removed by the employee who applied it. This ensures that the person who is in control of the hazardous energy is the one to re-energize the equipment. There are specific procedures for rare exceptions when the authorized employee is not available, but the primary rule is personal removal.

Question 182: What is the maximum height-to-base ratio for a freestanding mobile scaffold before additional stabilization is required?

2:1
4:1
3:1 (Correct answer)
5:1

Correct answer: 3:1

The height of a mobile scaffold must not exceed 3 times the minimum base dimension without additional outriggers or ties.

Question 183: What does the acronym 'SMART' stand for when setting safety performance objectives?

Systematic, Measurable, Actionable, Realistic, Trackable
Specific, Measurable, Achievable, Relevant, Time-bound (Correct answer)
Safety, Management, Assessment, Reporting, Training
Strategic, Motivational, Accountable, Reviewable, Targeted

Correct answer: Specific, Measurable, Achievable, Relevant, Time-bound

SMART goals in safety management are Specific (clearly defined), Measurable (quantifiable), Achievable (realistic given resources), Relevant (aligned with organizational safety priorities), and Time-bound (with a defined deadline).

Question 184: A construction worker notices smoke coming from electrical conduit inside a wall cavity. Which type of fire extinguisher is appropriate?

Class C-rated extinguisher (Correct answer)
Class B CO2 extinguisher
Class A water extinguisher
Class D dry powder extinguisher

Correct answer: Class C-rated extinguisher

Electrical fires require a Class C-rated extinguisher because water-based agents conduct electricity and could endanger the user.

Question 185: What does the 'action level' represent in OSHA's chemical exposure standards, and what obligations does it trigger?

The same concentration as the PEL
The IDLH concentration divided by 10
The concentration at which work must immediately stop
The concentration at which medical surveillance, exposure monitoring, and preventive programs are required — typically set at half the PEL (Correct answer)

Correct answer: The concentration at which medical surveillance, exposure monitoring, and preventive programs are required — typically set at half the PEL

The action level, typically set at half the PEL, triggers medical surveillance, exposure monitoring, training, and preventive programs even though the legal maximum exposure has not been exceeded.

Question 186: What is the minimum approach distance for unqualified workers near exposed energized parts operating at 50–300 volts under OSHA 1910.333?

Avoid contact — no specific distance required for low voltage (Correct answer)
3 feet 6 inches
10 feet
Any distance, as long as PPE is worn

Correct answer: Avoid contact — no specific distance required for low voltage

For voltages up to 300V, unqualified workers must avoid contact but OSHA does not specify a minimum numeric distance; qualified workers' approach distances apply.

Question 187: What is the purpose of a toe board on a scaffold platform?

Anchor the scaffold to the structure
Prevent tools and materials from falling off the platform edge (Correct answer)
Support the weight of midrails
Provide additional footing for workers

Correct answer: Prevent tools and materials from falling off the platform edge

Toe boards prevent materials, tools, and debris from being kicked or rolling off scaffold platforms onto workers below.

Question 188: Under OSHA's recordkeeping requirements, which of the following construction injuries must be recorded on the OSHA 300 log?

A bee sting with no allergic reaction
A work-related fracture requiring no days away from work (Correct answer)
A minor first-aid-only cut treated with a bandage
A headache that resolves without treatment

Correct answer: A work-related fracture requiring no days away from work

All work-related fractures are OSHA-recordable injuries regardless of whether they result in days away from work or restricted duty.

Question 189: In a fault tree analysis (FTA) of a scaffold collapse, an AND gate means that:

Either of the linked events alone can cause the top event
Only the most likely event needs to be addressed
The sequence of events is irrelevant to the outcome
All linked events must occur simultaneously for the outcome to result (Correct answer)

Correct answer: All linked events must occur simultaneously for the outcome to result

An AND gate in FTA indicates that the output event occurs only when ALL of the input events occur simultaneously, making it useful for identifying compound failure modes.

Question 190: A site safety committee has been active for eight months but key performance indicators have not improved. What is the MOST likely programmatic reason for this outcome?

Too many craft workers are involved in committee deliberations
Management is not following through on committee findings and recommendations (Correct answer)
The committee is meeting more frequently than necessary
The committee lacks a formal OSHA mandate requiring its existence

Correct answer: Management is not following through on committee findings and recommendations

Safety committees generate value only when management commits to acting on their recommendations. Without visible follow-through, corrective actions stall, worker trust erodes, and the committee becomes a compliance exercise rather than a driver of improvement.

Question 191: Fissured soil discovered during excavation typically indicates what type of soil classification?

Type B or C depending on other factors (Correct answer)
Type B
Type C
Type A

Correct answer: Type B or C depending on other factors

Fissured soil is excluded from Type A classification and may be Type B or Type C depending on its other properties and conditions.

Question 192: During a daily inspection, a competent person notices water accumulating in the bottom of a 6-foot deep trench. Which of the following is a primary and immediate responsibility of the competent person?

Document the finding in the daily log.
Remove exposed employees from the hazardous area. (Correct answer)
Continue work as long as the water is below boot level.
Monitor the water level to see if it increases.

Correct answer: Remove exposed employees from the hazardous area.

Per 1926.651(k)(2), if a competent person finds evidence of a situation that could result in a possible cave-in, such as water accumulation, exposed employees shall be removed from the hazardous area until the necessary precautions have been taken to ensure their safety.

Question 193: A construction site has a permit-required confined space. Which element is NOT required before entry?

Ensuring a trained attendant is stationed outside
Testing atmospheric conditions for oxygen and hazardous gases
Issuing an entry permit signed by an authorized entrant
Completing a written post-entry debrief within 24 hours (Correct answer)

Correct answer: Completing a written post-entry debrief within 24 hours

OSHA's confined space standard (29 CFR 1926.1203) requires atmospheric testing, a valid entry permit, and an attendant, but does not mandate a written post-entry debrief within 24 hours.

Question 194: During a multi-crane tandem lift, what is the most critical coordination requirement?

Both cranes must be the same manufacturer and model
A detailed lift plan with designated communication protocols and a single designated person directing the lift (Correct answer)
The cranes must operate at identical boom lengths at all times
Only the more experienced operator needs to monitor the load chart

Correct answer: A detailed lift plan with designated communication protocols and a single designated person directing the lift

Tandem lifts require a comprehensive lift plan with clear communication procedures and one qualified person directing the operation to prevent uneven load distribution and potential crane upset.

Question 195: During a toolbox talk on struck-by hazards, which control is considered most effective for protecting workers from swing radius hazards when a crane is operating?

Establishing and enforcing physical barricades around the swing radius (Correct answer)
Conducting daily briefings with all workers
Wearing high-visibility vests
Posting warning signs at crane access points

Correct answer: Establishing and enforcing physical barricades around the swing radius

Physical barricades prevent unauthorized entry into the swing radius, eliminating the exposure rather than relying on worker behavior.

Question 196: A construction electrician is working on a 480V motor control center. After locking out the breaker, what is the next critical step before touching conductors?

Notify the building owner that power is off
Wait 30 minutes for residual current to dissipate
Test for absence of voltage using an appropriate voltage tester (Correct answer)
Apply insulating blankets over the breaker panel

Correct answer: Test for absence of voltage using an appropriate voltage tester

After lockout, workers must verify zero energy state by testing with a voltmeter or tick tracer rated for the voltage before touching any conductors.

Question 197: After a fall arrest event, when must equipment that arrested a fall be removed from service?

After a visual inspection clears it
Only if visibly damaged
Immediately, until inspected by the manufacturer or competent person (Correct answer)
After 30 days

Correct answer: Immediately, until inspected by the manufacturer or competent person

All fall arrest equipment involved in stopping a fall must be immediately removed from service and inspected before reuse.

Question 198: Under OSHA 1926.59 (Hazard Communication for construction), which of the following is a required element of a GHS-compliant chemical label?

SDS number, product code, and emergency phone number only
Signal word ('Danger' or 'Warning'), hazard pictograms, hazard statements, precautionary statements, product identifier, and supplier information (Correct answer)
CAS number, LD50, boiling point, and flashpoint
Only the chemical name and NFPA diamond rating

Correct answer: Signal word ('Danger' or 'Warning'), hazard pictograms, hazard statements, precautionary statements, product identifier, and supplier information

GHS labels under OSHA's HazCom standard must include: product identifier, signal word, hazard pictograms, hazard statements, precautionary statements, and supplier information including name and address.

Question 199: Hand-arm vibration syndrome (HAVS) is most associated with prolonged use of which type of construction tool?

Electric conduit benders
Chipping hammers and grinders (Correct answer)
Powder-actuated nail guns
Hydraulic man-lifts

Correct answer: Chipping hammers and grinders

HAVS (also called vibration white finger) results from chronic exposure to hand-transmitted vibration typically above 2.5 m/s² A(8). Chipping hammers, grinders, jackhammers, and similar vibratory hand tools are the primary sources in construction. Powder-actuated tools fire too briefly; lifts and benders transmit minimal hand-arm vibration.

Question 200: The OSHA 301 Injury and Illness Incident Report must be completed within how many calendar days of a recordable incident?

24 hours
7 days (Correct answer)
15 days
30 days

Correct answer: 7 days

OSHA requires the 301 form (or equivalent) to be completed within 7 calendar days after the employer learns of a recordable work-related injury or illness.

CHST (Construction Health and Safety Technician) Exam

The CHST (Construction Health and Safety Technician) Exam exam validates essential knowledge and skills required for certification or licensure in this field.

200

Questions

240 min

Time Limit

68%

To Pass

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