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

Question 1: A portable fire extinguisher rated '2-A:10-B:C' is appropriate for use on which types of fires?

Class B and Class C fires only
Class A and Class B fires only
Class A, Class B, and Class C fires (Correct answer)
Class A and Class C fires only

Correct answer: Class A, Class B, and Class C fires

The 'A:B:C' rating indicates the extinguisher is suitable for ordinary combustibles (A), flammable liquids (B), and electrical fires (C).

Question 2: An entrant working inside a permit-required confined space notices an unusual odor and begins to feel dizzy. What is the correct immediate action?

Don the supplied-air respirator stored inside the space and continue the task
Immediately exit the space and notify the attendant (Correct answer)
Notify the attendant and continue working while the hazard is assessed
Wait for the entry supervisor to arrive and authorize evacuation

Correct answer: Immediately exit the space and notify the attendant

Entrants must immediately self-rescue by exiting the space upon any warning sign of a hazardous condition; delay risks incapacitation and death as atmospheric conditions can deteriorate within seconds.

Question 3: Under OSHA 1926.652, what is the maximum allowable slope for Type C soil when using the sloping method of protection?

¾H:1V (53 degrees)
1H:1V (45 degrees)
½H:1V (63 degrees)
1½H:1V (34 degrees from horizontal) (Correct answer)

Correct answer: 1½H:1V (34 degrees from horizontal)

For Type C soil, the least stable classification, OSHA requires a maximum slope of 1½H:1V (1.5 feet horizontal for every 1 foot vertical), which equals approximately 34 degrees from horizontal.

Question 4: Which inspection is required before each shift for wire rope slings used in construction rigging?

Only a monthly inspection logged in the crane maintenance book
A documented third-party inspection with load testing
An ultrasonic thickness test of each wire strand
A visual inspection by a competent person for damage, kinks, bird-caging, and corrosion (Correct answer)

Correct answer: A visual inspection by a competent person for damage, kinks, bird-caging, and corrosion

OSHA requires that wire rope slings be visually inspected before each use by a competent person to identify defects such as kinking, crushing, bird-caging, or broken wires.

Question 5: When is a safety monitoring system (SMS) an acceptable sole means of fall protection on a low-slope roof?

Any time a competent person is available
Whenever fewer than 10 workers are on the roof
Only for roofs 50 feet wide or less with a slope of 4:12 or less (Correct answer)
Only on roofs with no penetrations

Correct answer: Only for roofs 50 feet wide or less with a slope of 4:12 or less

OSHA permits SMS as the sole fall protection method only on low-slope roofs 50 feet or less in width.

Question 6: Which soil test involves rolling a moist soil sample into a thread and observing if it crumbles?

Pocket penetrometer test
Thumb penetration test
Thread test (Correct answer)
Ribbon test

Correct answer: Thread test

The thread test (dry strength test) checks cohesion by rolling soil into a 1/8-inch thread; if it holds, the soil has higher cohesion.

Question 7: Under OSHA 29 CFR 1926, what is the minimum safe distance workers on foot must maintain from the path of a swinging crane load unless otherwise protected?

10 feet (Correct answer)
The load's maximum radius plus 2 feet
15 feet
6 feet

Correct answer: 10 feet

OSHA 29 CFR 1926.1425 requires workers to stay at least 10 feet away from the path of a swinging crane load or be protected by a physical barrier. This prevents struck-by injuries from load swing or dropped material.

Question 8: Under OSHA's recordkeeping standard 1904.5, how is 'work-relatedness' determined for an injury or illness?

Workers' compensation board determinations govern OSHA work-relatedness
An injury is work-related only if it occurred on the employer's physical premises
Work-relatedness is determined solely by whether the worker was on the clock at the time of injury
An injury or illness is work-related if an event or exposure in the work environment either caused or contributed to the condition, or significantly aggravated a pre-existing condition (Correct answer)

Correct answer: An injury or illness is work-related if an event or exposure in the work environment either caused or contributed to the condition, or significantly aggravated a pre-existing condition

OSHA 1904.5 defines work-relatedness as any injury, illness, or aggravation of a pre-existing condition caused or contributed to by an event or exposure in the work environment — location and clock time alone do not determine work-relatedness.

Question 9: An employer wants to use a protective method that differs from an OSHA standard but provides equal protection. What formal mechanism should it pursue?

Request an informal conference
Ignore the standard and document the reason
File a notice of contest
Apply for a variance (Correct answer)

Correct answer: Apply for a variance

A permanent variance allows an alternative method if the employer demonstrates it provides protection at least as effective as the standard.

Question 10: What is the OSHA permissible exposure limit (PEL) for benzene in construction as an 8-hour TWA?

1 ppm (Correct answer)
0.5 ppm
10 ppm
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 11: During a confined space entry, the attendant's PRIMARY duty is to:

Perform atmospheric testing inside the permit space
Assist entrants with tools as needed
Operate rescue equipment inside the space
Monitor entrants and maintain continuous communication (Correct answer)

Correct answer: Monitor entrants and maintain continuous communication

The attendant must maintain continuous communication with entrants and be ready to initiate rescue, not enter the space.

Question 12: A CHST learns confidential information about a former client's pending litigation while working on a new project with a competitor. What does professional ethics require?

Post it anonymously online
Keep the information confidential unless disclosure is required by law or to prevent imminent harm (Correct answer)
Share it if it improves safety on the new project
Sell it to the competitor

Correct answer: Keep the information confidential unless disclosure is required by law or to prevent imminent harm

Safety professionals must protect confidential client information except where law or imminent danger to people requires disclosure.

Question 13: A confined space attendant observes an unauthorized person attempting to enter the permit space. The attendant's FIRST action should be to:

Physically block the person from entering
Warn the unauthorized person to stay out and inform the supervisor (Correct answer)
Evacuate the authorized entrants first
Call 911 immediately

Correct answer: Warn the unauthorized person to stay out and inform the supervisor

The attendant must warn unauthorized individuals away and notify the entry supervisor; physically restraining someone is not the attendant's role.

Question 14: A construction supervisor notices a worker wearing a hard hat that has been painted. What is the safety concern?

Painted hard hats cannot be inspected for cracks visually
Painted hard hats violate OSHA regulations directly
The color change makes it harder to identify the worker's role
Paint solvents can degrade the shell material and reduce impact protection (Correct answer)

Correct answer: Paint solvents can degrade the shell material and reduce impact protection

Solvents and chemicals in paint can penetrate and weaken the polycarbonate or ABS shell of a hard hat, compromising its impact and penetration resistance.

Question 15: During post-tensioning operations, what does OSHA require regarding the area behind the jack?

No employee except those essential may be behind the jack, and signs and barriers must be erected (Correct answer)
Only the jack operator may stand directly behind it
Workers may stand behind it if wearing face shields
The area must be enclosed with a 42-inch guardrail only

Correct answer: No employee except those essential may be behind the jack, and signs and barriers must be erected

1926.701(c) keeps non-essential employees from behind the jack and requires signs and barriers to limit access.

Question 16: What is the OSHA-required voltage threshold below which electrical work is generally considered low-voltage on construction sites?

120 volts
24 volts
50 volts (Correct answer)
240 volts

Correct answer: 50 volts

OSHA generally considers 50 volts as the threshold below which electrical shock hazards are significantly reduced, though hazards can still exist.

Question 17: Under OSHA's Respiratory Protection Standard (29 CFR 1910.134), which type of respirator provides the highest level of protection?

Half-face air-purifying respirator
Self-Contained Breathing Apparatus (SCBA) (Correct answer)
Supplied-air respirator (SAR)
Full-face air-purifying respirator

Correct answer: Self-Contained Breathing Apparatus (SCBA)

An SCBA provides the highest protection because it supplies its own air source, offering complete independence from the ambient atmosphere and full facial coverage.

Question 18: What is the primary health concern when construction workers are exposed to hydrogen sulfide (H2S) gas in sewer line excavation work?

Permanent hearing loss
Skin irritation and chemical burns
Olfactory fatigue leading to undetected lethal exposure (Correct answer)
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 19: Before an employer places construction loads on a concrete structure, who must determine the structure can support them?

The concrete supplier
The local building inspector
A qualified person, based on information received (Correct answer)
The site foreman alone

Correct answer: A qualified person, based on information received

1926.701(a) prohibits construction loads unless the employer determines, based on information from a qualified person, that the structure can support them.

Question 20: Skylights and roof openings must be guarded when they present a fall hazard. What is the minimum guardrail height required around such openings under OSHA 1926.502?

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

Correct answer: 42 inches

OSHA 1926.502(b) requires guardrail systems to be 42 inches (plus or minus 3 inches) in height.

Question 21: What is the maximum noise exposure allowed by OSHA for an 8-hour workday without hearing protection?

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

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

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

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 23: Which safety program structure best describes one where each worker takes turns leading a safety meeting or inspection?

Behavior-based safety observation only
Peer-led or rotating safety ownership (Correct answer)
Management-by-walking-around
Top-down safety management

Correct answer: Peer-led or rotating safety ownership

Peer-led or rotating safety ownership increases worker engagement and accountability by giving all employees active roles in the safety process.

Question 24: Which action should be taken FIRST to lessen a painter's exposure to volatile organic compounds (VOCs) contained in oil-based paint, according to the hierarchy of controls?

Reduce the amount of time the worker paints on any given day.
Replace the paint with a water-based formulation. (Correct answer)
Restrict oil-based paints to exterior application only.
Provide the painter with an air-purifying respirator with organic vapor cartridges.

Correct answer: Replace the paint with a water-based formulation.

The hierarchy of controls is set up so that the best hazard mitigation strategy is chosen before less protective ones. Elimination is the first factor to be taken into account when using this theory; if there is no danger, there is no hazard. VOC exposure can be avoided by switching to a water-based paint instead of an oil-based one.

Question 25: Which factor does NOT affect a crane's rated load capacity?

Wind speed
Boom angle
Boom length
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 26: According to NFPA 70E, what is the primary purpose of an Energized Electrical Work Permit?

To authorize unqualified workers to perform electrical tasks under supervision
To document justification, risk assessment, and safety measures when work on energized equipment cannot be avoided (Correct answer)
To satisfy OSHA recordkeeping requirements for electrical incidents
To replace LOTO procedures for low-voltage systems

Correct answer: To document justification, risk assessment, and safety measures when work on energized equipment cannot be avoided

An Energized Electrical Work Permit formally documents why de-energizing is not feasible, the hazard analysis, required PPE, and approval chain before energized work begins.

Question 27: Which type of glove material provides the BEST protection against ketone solvents commonly found on construction sites?

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

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

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

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 29: Under OSHA 29 CFR 1926.65 (HAZWOPER), workers performing hazardous waste site clean-up operations must receive how many hours of initial training before working on-site unsupervised?

16 hours
24 hours
40 hours (Correct answer)
8 hours

Correct answer: 40 hours

OSHA's HAZWOPER standard at 29 CFR 1926.65(e)(3) requires a minimum of 40 hours of off-site training plus 3 days of supervised field experience for general site workers.

Question 30: What is the maximum permissible noise exposure level for an 8-hour time-weighted average under OSHA construction standards (29 CFR 1926.52)?

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

Correct answer: 90 dBA

OSHA's permissible exposure limit for construction noise is 90 dBA as an 8-hour TWA under 29 CFR 1926.52.

Question 31: Three characteristics that define a 'confined space' under OSHA include all of the following EXCEPT:

Contains electrical or mechanical hazards (Correct answer)
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

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 32: A safety professional calculates the incident rate for a company with 3 recordable injuries, 100 employees working 40 hrs/week for 50 weeks. What is the TRIR?

1.5
6.0
3.0 (Correct answer)
0.6

Correct answer: 3.0

TRIR = (Number of recordable injuries × 200,000) ÷ total hours worked; (3 × 200,000) ÷ (100 × 40 × 50) = 600,000 ÷ 200,000 = 3.0.

Question 33: What does the term 'competent person' mean under OSHA construction standards?

Any worker with at least five years of experience
A licensed professional engineer only
A person designated by the employer who can identify hazards and has authority to take corrective action (Correct answer)
A third-party safety consultant hired for the project

Correct answer: A person designated by the employer who can identify hazards and has authority to take corrective action

OSHA defines a competent person as someone capable of identifying existing and predictable hazards and authorized to take prompt corrective measures.

Question 34: Which four elements must a plaintiff typically prove to establish negligence against a safety professional?

Intent, motive, opportunity, harm
Duty, breach of duty, causation, damages (Correct answer)
Notice, hearing, appeal, judgment
Contract, offer, acceptance, consideration

Correct answer: Duty, breach of duty, causation, damages

Negligence requires a duty owed, a breach of that duty, causation linking the breach to the harm, and actual damages.

Question 35: 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
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
One authorized employee removes all locks and notifies the others

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 36: 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)
95 decibels (dB)
75 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 37: According to ANSI/ISEA 107, which class of high-visibility safety apparel provides the highest level of conspicuity and is required for workers near high-speed roadways?

Class 1
Class 2
Class 3 (Correct answer)
Class E

Correct answer: Class 3

Class 3 high-visibility apparel offers the greatest visibility and is required for workers in high-speed, complex traffic environments where full-body visibility is needed.

Question 38: A construction company's Experience Modification Rate (EMR) is 1.35. What does this indicate?

The company received a 35% premium discount
The company has 35% fewer claims than average
The company's injury costs are 35% below the industry average
The company's injury costs are 35% above the industry average (Correct answer)

Correct answer: The company's injury costs are 35% above the industry average

An EMR above 1.0 means the employer's workers' compensation losses exceed the industry average; 1.35 indicates costs are 35% higher than average.

Question 39: An employer must report the in-patient hospitalization of an employee to OSHA. According to 29 CFR 1904.39, this report must be made within what timeframe?

8 hours of the incident.
7 calendar days of the hospitalization.
24 hours of learning about the hospitalization. (Correct answer)
48 hours of the incident.

Correct answer: 24 hours of learning about the hospitalization.

According to OSHA 29 CFR 1904.39(a)(2), an employer must report an in-patient hospitalization to OSHA within 24 hours of knowing about it. The 8-hour timeframe is for reporting a fatality. The clock for reporting starts when the employer learns of the qualifying event, not necessarily when the incident occurred.

Question 40: Which instrument is the preferred choice for real-time monitoring of worker exposure to organic vapor solvents on a construction site?

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

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 41: When a crane operator cannot see the load at all times, what must be done?

Use a signal person (Correct answer)
Stop the lift immediately
Switch to radio communication only
Reduce the load by 25%

Correct answer: Use a signal person

OSHA requires a qualified signal person whenever the operator does not have a clear view of the load or path of travel.

Question 42: When selecting chemical protective clothing (CPC) for a worker handling a highly corrosive acid, which factor is MOST important to evaluate first?

Color coding for site identification purposes
Comfort and range of motion for the worker
Breakthrough time of the chemical through the material (Correct answer)
Cost and availability of replacement garments

Correct answer: Breakthrough time of the chemical through the material

Breakthrough time — the time for a chemical to permeate through the CPC material at a detectable level — is the primary criterion because it determines the duration of safe use.

Question 43: What does a yellow color-coding designation typically indicate on construction sites under ANSI/ISEA standards?

Fire safety equipment location
Caution or physical hazard (Correct answer)
First aid equipment location
Radiation hazard area

Correct answer: Caution or physical hazard

Yellow is the standard color for caution and physical hazards such as tripping, falling, or striking hazards under ANSI safety color standards.

Question 44: A construction worker falls from scaffolding and is hospitalized. During the investigation, the team discovers the scaffold was missing guardrails and the worker had no fall protection training. Which investigation finding represents a SYSTEM-level root cause?

The guardrails were removed by a subcontractor
The company lacked a scaffold inspection program (Correct answer)
The worker chose not to wear a harness
The scaffold was erected on uneven ground

Correct answer: The company lacked a scaffold inspection program

The absence of a scaffold inspection program is a system-level root cause because it represents a management system failure that allowed the unsafe condition to persist undetected.

Question 45: What is the Plan-Do-Check-Act (PDCA) cycle, and how does it apply to construction safety management systems per ANSI Z10 and ISO 45001?

PDCA refers to the four phases of a construction project: Planning, Design, Construction, Acceptance
PDCA is an OSHA-mandated audit process for contractors with more than 100 workers
PDCA is a continuous improvement cycle: Plan (set objectives and identify hazards), Do (implement controls and programs), Check (monitor and measure performance), Act (correct deficiencies and improve the system) (Correct answer)
PDCA is a hazard reporting form used by OSHA during inspections

Correct answer: PDCA is a continuous improvement cycle: Plan (set objectives and identify hazards), Do (implement controls and programs), Check (monitor and measure performance), Act (correct deficiencies and improve the system)

The Plan-Do-Check-Act cycle from quality management has been adopted by ANSI Z10 and ISO 45001 as the framework for continuous improvement of occupational health and safety management systems.

Question 46: What is the purpose of a 'try-out' (or test) step after applying lockout to a machine?

To check that all affected employees have been notified
To verify the machine cannot be started before work begins (Correct answer)
To confirm the lock is properly seated on the hasp
To test the emergency stop button operation

Correct answer: To verify the machine cannot be started before work begins

The try-out step verifies the energy isolation was successful by attempting to start or operate the equipment before performing maintenance.

Question 47: Under the OSH Act's General Duty Clause (Section 5(a)(1)), an employer can be cited even without a specific OSHA standard if which conditions are met?

A fatality occurred and a union filed a complaint
A recognized hazard exists, is causing or likely to cause serious harm, and a feasible abatement method is available (Correct answer)
The employer has a prior citation history within the past three years
More than 10 employees are exposed to the same condition

Correct answer: A recognized hazard exists, is causing or likely to cause serious harm, and a feasible abatement method is available

The General Duty Clause requires OSHA to show the hazard is recognized by the industry or employer, poses serious harm potential, and can be abated by a feasible means.

Question 48: Under OSHA 1926.503, what are the requirements for fall protection training on construction sites?

OSHA 10-hour training satisfies all fall protection training requirements
Any supervisor may conduct fall protection training without specific qualifications
Workers only need to watch a fall protection video once per employment
Workers must be trained by a qualified person on fall hazards, use and limitations of fall protection systems, and correct procedures for erecting, maintaining, and dismantling fall protection — training must be specific to the work conditions (Correct answer)

Correct answer: Workers must be trained by a qualified person on fall hazards, use and limitations of fall protection systems, and correct procedures for erecting, maintaining, and dismantling fall protection — training must be specific to the work conditions

OSHA 1926.503(a)(1) requires each worker exposed to fall hazards to be trained by a qualified person — covering the nature of fall hazards in the work area, correct procedures for erecting and using fall protection systems, and each worker's role in the fall protection plan.

Question 49: What is the minimum distance a scaffold must be maintained from power lines rated at 50 kV or less?

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

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 50: What retrieval system components are required when workers enter a permit-required confined space where non-entry rescue may be needed?

Standard work belt with a rope tied to a fixed point inside the space
Full-body harness and wristlets connected to a retrieval line and mechanical lifting device outside the space (Correct answer)
Self-contained breathing apparatus with a buddy system inside
A retrieval rope attached to the worker's ankle and secured to the entrance

Correct answer: Full-body harness and wristlets connected to a retrieval line and mechanical lifting device outside the space

OSHA requires full-body harnesses and wristlets connected to a retrieval line attached to a mechanical device or fixed point outside the space to enable non-entry rescue without exposing rescuers to the same hazards.

Question 51: Which weighting network and meter response does OSHA specify for measuring noise for compliance?

A-weighting, fast response
C-weighting, fast response
A-weighting, slow response (Correct answer)
Z-weighting, impulse response

Correct answer: A-weighting, slow response

OSHA noise levels are measured on the A-weighted scale at slow response.

Question 52: Which federal agency is primarily responsible for enforcing workplace safety and health standards in the construction industry?

MSHA
EPA
OSHA (Correct answer)
NIOSH

Correct answer: OSHA

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

Question 53: A worker develops contact dermatitis after repeated exposure to Portland cement. What is the PRIMARY causative agent?

Calcium silicate dust causing abrasive irritation
Calcium oxide causing pH-neutral reaction
Silicon dioxide triggering an allergic response
Hexavalent chromium acting as a sensitizer (Correct answer)

Correct answer: Hexavalent chromium acting as a sensitizer

Hexavalent chromium (Cr VI) present in Portland cement is a known skin sensitizer that causes allergic contact dermatitis with repeated exposure.

Question 54: What oxygen concentration range is considered acceptable for entry into a confined space?

19.5% to 23.5% (Correct answer)
16% to 21%
18% to 25%
14.5% to 23.5%

Correct answer: 19.5% to 23.5%

OSHA defines the acceptable oxygen range as 19.5% to 23.5%; below 19.5% is oxygen-deficient and above 23.5% is oxygen-enriched, both requiring special precautions.

Question 55: After a serious incident, a superintendent tells the CHST to discard damaged rigging before investigators arrive. What legal concern does this raise?

Respondeat superior
Spoliation of evidence (Correct answer)
Comparative negligence
Assumption of risk

Correct answer: Spoliation of evidence

Destroying or altering evidence relevant to an investigation or anticipated litigation is spoliation and can bring sanctions or criminal liability.

Question 56: When using a safety net system, what is the maximum distance the net can be placed below the working surface?

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

Correct answer: 30 feet

OSHA 1926.502(c)(1) states safety nets shall be installed no more than 30 feet below the walking/working surface.

Question 57: According to the hierarchy of controls, which method is considered the MOST effective way to protect workers from construction hazards?

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

Correct answer: Elimination

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

Question 58: Which control most effectively reduces whole-body vibration for a loader operator?

Increasing travel speed to shorten cycle time
Giving the operator anti-vibration gloves
Adding 10 minutes of stretching at lunch
Keeping a suspension seat adjusted for the operator's weight and keeping haul roads smooth (Correct answer)

Correct answer: Keeping a suspension seat adjusted for the operator's weight and keeping haul roads smooth

Suspension seats and well-maintained travel surfaces cut the vibration that reaches the operator's spine.

Question 59: During fall protection training, workers should be taught that the total fall distance in a PFAS includes which components?

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

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 60: The IDLH (Immediately Dangerous to Life or Health) value for a chemical represents:

The level at which a chemical becomes flammable in air
The concentration that causes no observable effect after 8 hours of exposure
The permissible exposure limit set by OSHA for an 8-hour workday
The maximum concentration from which an unprotected worker can escape within 30 minutes without irreversible health effects (Correct answer)

Correct answer: The maximum concentration from which an unprotected worker can escape within 30 minutes without irreversible health effects

IDLH is defined by NIOSH as the maximum concentration from which a worker could escape within 30 minutes without experiencing escape-impairing symptoms or irreversible health effects.

Question 61: What is the OSHA-required minimum distance that a scaffold must be erected from an energized power line rated at 50 kV or less?

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

Correct answer: 10 feet

OSHA 1926.416 requires scaffolds to be erected at least 10 feet from energized power lines rated 50 kV or less.

Question 62: A construction worker is performing roofing work on a 5/12 slope. Which fall protection method is LEAST appropriate for this situation?

Personal fall arrest system
Guardrail system
Warning line system alone without a safety monitor (Correct answer)
Safety net system

Correct answer: Warning line system alone without a safety monitor

A warning line system alone (without a safety monitor or PFAS inside the warning line zone) is not permitted for workers on slopes steeper than 4/12.

Question 63: What is the maximum allowable deflection for the top rail of a guardrail system when a 200-pound force is applied?

1 inch
6 inches
3 inches
The rail must not deflect beyond the edge of the surface (Correct answer)

Correct answer: The rail must not deflect beyond the edge of the surface

Per OSHA 1926.502(b)(3), the top rail must not deflect to a height less than 39 inches and must not go beyond the edge of the walking/working surface.

Question 64: Why must exposed protruding rebar be capped or otherwise guarded under 1926.701(b)?

To mark the rebar location for inspectors
To prevent corrosion before the concrete pour
To eliminate the impalement hazard (Correct answer)
To keep the rebar from conducting electricity

Correct answer: To eliminate the impalement hazard

1926.701(b) requires protruding reinforcing steel to be guarded so it cannot impale workers.

Question 65: What does the acronym 'SMART' stand for when setting safety performance objectives?

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

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 66: When must a pre-lift meeting be conducted on a critical lift?

Before the lift begins, with all personnel involved in the operation (Correct answer)
Only when a new operator is performing the lift
After the load is rigged but before it leaves the ground
Only when the load exceeds 100 tons

Correct answer: Before the lift begins, with all personnel involved in the operation

Pre-lift meetings must occur before the lift to ensure all personnel understand the plan, signals, hazards, and responsibilities.

Question 67: What does the acronym 'SDS' stand for in the context of chemical hazard communication?

Safety Data Sheet (Correct answer)
Standard Disclosure Statement
Structural Data Sheet
Substance Danger Summary

Correct answer: Safety Data Sheet

SDS stands for Safety Data Sheet, which replaced the Material Safety Data Sheet (MSDS) under OSHA's revised Hazard Communication Standard aligned with GHS.

Question 68: Which OSHA construction standard governs electrical safety requirements specifically for the construction industry, as distinct from general industry?

29 CFR 1910.147
29 CFR 1910.301–399
29 CFR 1926.400–449 (Correct answer)
29 CFR 1926.502

Correct answer: 29 CFR 1926.400–449

Subpart K (29 CFR 1926.400–449) of OSHA's construction standards covers electrical safety requirements specific to construction activities.

Question 69: Which OSHA construction standard sets the permissible noise exposure limits shown in Table D-2?

29 CFR 1910.95
29 CFR 1926.101
29 CFR 1926.52 (Correct answer)
29 CFR 1926.21

Correct answer: 29 CFR 1926.52

29 CFR 1926.52 contains the construction occupational noise exposure limits in Table D-2.

Question 70: What is the minimum safe distance a crane must maintain from energized power lines rated at 50 kV or below?

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

Correct answer: 10 feet

OSHA 29 CFR 1926.1408 requires a minimum 10-foot clearance from energized power lines up to 50 kV.

Question 71: Which document establishes the minimum safety and health requirements for a permit-required confined space entry program?

OSHA 29 CFR 1926.21
ANSI Z87.1
OSHA 29 CFR 1910.146 (Correct answer)
NFPA 101

Correct answer: OSHA 29 CFR 1910.146

OSHA 29 CFR 1910.146 covers permit-required confined spaces and is applied to construction via 1926.21 reference.

Question 72: 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?

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

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

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

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 74: What danger is present when painters and electricians are finishing in the same room during the last stages of a project?

Fire (Correct answer)
Noise
Slips, trips, and falls
Improper illumination

Correct answer: Fire

The risks posed by numerous activities taking place in one site must be taken into account whenever multiple trades or contractors are working there. As an illustration, while painters are painting trim using oil-based paint (a flammable hazard), electricians may be checking the lights (an ignite source). The combustible fumes from this job could catch fire if sparks from the work are produced. The risks associated with each task can increase if you work close to other contractors.

Question 75: Who has the authority and responsibility to cancel a confined space entry permit if conditions become unsafe?

The attendant
The company safety director
The authorized entrant
The entry supervisor (Correct answer)

Correct answer: The entry supervisor

The entry supervisor has the authority and responsibility to cancel the entry permit if conditions change or a hazard develops that makes the space unsafe for entry.

Question 76: What is the minimum safe distance from energized overhead power lines rated at 50 kV or below that OSHA requires for uninsulated equipment?

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

Correct answer: 10 feet

OSHA 29 CFR 1926.550 requires a minimum clearance of 10 feet from power lines up to 50 kV for uninsulated equipment and workers.

Question 77: What is the primary role of a Safety Data Sheet (SDS) in construction site hazard communication?

To provide detailed information about a chemical's hazards, handling, storage, and emergency measures (Correct answer)
To document daily toolbox talk attendance
To replace the need for container labeling
To serve as an employee training certificate

Correct answer: To provide detailed information about a chemical's hazards, handling, storage, and emergency measures

An SDS provides comprehensive information about chemical identity, hazards, safe handling procedures, and emergency response measures.

Question 78: Under OSHA 1926.35, what must be included in an Emergency Action Plan (EAP) for construction sites?

Location of first aid kits and AEDs only
Fire extinguisher placement and annual inspection records
Evacuation procedures and routes, procedures for employees who remain to operate critical operations, procedures to account for all employees after evacuation, rescue and medical duties, means of reporting emergencies, and names of contacts for more information (Correct answer)
Only emergency contact phone numbers

Correct answer: Evacuation procedures and routes, procedures for employees who remain to operate critical operations, procedures to account for all employees after evacuation, rescue and medical duties, means of reporting emergencies, and names of contacts for more information

OSHA 1926.35 requires an EAP to include evacuation procedures and routes, procedures for remaining employees, accountability procedures, rescue and medical duties, emergency reporting procedures, and a contact person for more information.

Question 79: Which hierarchy of controls is MOST preferred when addressing a fall hazard on a construction site?

Personal fall arrest systems
Administrative controls such as warning lines
Elimination or substitution of the hazard (Correct answer)
Safety monitoring systems

Correct answer: Elimination or substitution of the hazard

The hierarchy of controls places elimination or substitution at the top, meaning redesigning the work to remove the fall hazard is always preferable.

Question 80: Which of the following is considered the LEAST effective method for controlling workplace hazards according to the hierarchy of controls?

Substitution
Administrative controls
Personal Protective Equipment (PPE) (Correct answer)
Engineering controls

Correct answer: Personal Protective Equipment (PPE)

The hierarchy of controls ranks hazard control methods from most to least effective. The order is: Elimination, Substitution, Engineering Controls, Administrative Controls, and finally, Personal Protective Equipment (PPE). PPE is considered the last line of defense because it relies on the worker to wear and use it correctly and does not remove the hazard from the environment.

Question 81: Which condition would require a permit-required confined space entry operation to be terminated immediately?

A new worker arrives who was not listed on the original entry permit
The entry permit expiration time is approaching within 2 hours
Detection of a prohibited condition such as an oxygen level drop to 18% (Correct answer)
A work shift change requiring new entrants to replace current workers

Correct answer: Detection of a prohibited condition such as an oxygen level drop to 18%

A prohibited condition—such as oxygen dropping below 19.5%, flammable gas reaching 10% LEL, or detection of toxic contaminants—requires immediate termination of entry and evacuation of the space.

Question 82: What is the primary role of a safety and health committee on a construction project according to best management practices?

To handle all workers' compensation claims
To replace the need for a full-time safety professional
To conduct all required OSHA training
To serve as a forum for worker-management cooperation in identifying and resolving safety concerns (Correct answer)

Correct answer: To serve as a forum for worker-management cooperation in identifying and resolving safety concerns

Safety committees function as collaborative bodies where workers and management jointly identify hazards, discuss concerns, and develop solutions.

Question 83: On a multi-employer construction site, who bears primary responsibility for ensuring emergency telephone numbers are posted?

OSHA's area office
Each individual subcontractor independently
The local municipality
The controlling employer or general contractor (Correct answer)

Correct answer: The controlling employer or general contractor

The general contractor (controlling employer) is responsible for overall site safety coordination, including posting emergency contact numbers prominently.

Question 84: What is the key difference between an 'incident' and an 'accident' in modern safety management terminology?

Incidents are investigated internally; accidents are reported to OSHA
Incidents include near-misses and unplanned events; 'accident' implies randomness that safety professionals avoid (Correct answer)
Accidents are OSHA-recordable; incidents are not
Incidents involve property damage only; accidents involve injuries

Correct answer: Incidents include near-misses and unplanned events; 'accident' implies randomness that safety professionals avoid

Modern safety science uses 'incident' because it encompasses near-misses and unplanned events, while 'accident' implies unpredictability and undermines the idea that events are preventable.

Question 85: What is the OSHA-required minimum safe distance from power lines for uninsulated overhead lines carrying up to 50 kV when using cranes or other equipment?

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

Correct answer: 10 feet

OSHA requires a minimum clearance of 10 feet from uninsulated overhead power lines carrying up to 50 kV under 29 CFR 1926.1408 for crane and derrick operations.

Question 86: 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 1926.1153 (Correct answer)
29 CFR 1926.55
29 CFR 1926.200
29 CFR 1926.62

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 87: A construction company wants to benchmark its safety program against industry standards. Which metric provides the MOST meaningful comparison?

Days Away, Restricted, or Transferred (DART) rate (Correct answer)
Total number of safety training hours
Number of safety committee meetings held
Annual safety budget as a percentage of revenue

Correct answer: Days Away, Restricted, or Transferred (DART) rate

The DART rate is a standardized OSHA metric that allows meaningful comparison across companies and industry sectors because it is calculated using a consistent formula.

Question 88: Under OSHA definitions, 'engulfment' in a confined space refers to:

The collapse of a confined space wall or ceiling onto an entrant
A rapid drop in oxygen levels that incapacitates an entrant
The surrounding and effective capture of a person by finely divided solids or liquid (Correct answer)
An entrant becoming disoriented due to toxic atmospheric conditions

Correct answer: The surrounding and effective capture of a person by finely divided solids or liquid

OSHA defines engulfment as the surrounding and effective capture of a person by a liquid or finely divided flowable solid, which can cause asphyxiation, strangulation, constriction, or crushing.

Question 89: Which safety principle does the phrase 'Heinrich's Triangle' (or Safety Triangle) represent?

For every fatality there are a predictable number of minor injuries and near-misses at lower levels (Correct answer)
The relationship between frequency, severity, and probability in risk assessment
The three levels of PPE hierarchy from primary to tertiary protection
The three parties responsible for safety: employer, employee, and regulator

Correct answer: For every fatality there are a predictable number of minor injuries and near-misses at lower levels

Heinrich's Triangle illustrates that for each serious injury there are many minor injuries and an even greater number of near-misses, suggesting near-miss control prevents major injuries.

Question 90: How must tremie sections be connected according to 1926.702?

Regular couplings only
Taped with duct tape for quick removal
Welded at each joint
Secured with wire rope or equivalent materials in addition to regular couplings (Correct answer)

Correct answer: Secured with wire rope or equivalent materials in addition to regular couplings

Sections of tremies must be secured with wire rope or equivalent in addition to the regular couplings or connections.

Question 91: 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:

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

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 92: A construction foreman notices that several Spanish-speaking workers did not understand a toolbox talk delivered only in English. What is the BEST corrective action?

Require workers to attend an English language class
Provide the toolbox talk again using a qualified interpreter or bilingual materials (Correct answer)
Document that training was provided and move forward
Post written English summaries at the job site entrance

Correct answer: Provide the toolbox talk again using a qualified interpreter or bilingual materials

Effective safety communication requires that workers actually comprehend the content, which may necessitate interpretation or translated materials.

Question 93: A competent person conducting a job hazard analysis identifies a floor hole 2 inches in diameter. What is the OSHA-required protection for this opening?

A guardrail system around the perimeter
No protection needed for holes under 6 inches
A cover capable of supporting twice the intended load (Correct answer)
A warning cone placed nearby

Correct answer: A cover capable of supporting twice the intended load

OSHA requires floor hole covers regardless of size, and covers must support twice the maximum intended load of workers and equipment.

Question 94: When must OSHA be notified of a work-related fatality?

Within 8 hours of learning about it (Correct answer)
Within 24 hours of the incident
At the next scheduled OSHA inspection
Within 72 hours by written report

Correct answer: Within 8 hours of learning about it

Employers must report all work-related fatalities to OSHA within 8 hours of learning about the death.

Question 95: What factor determines whether a lift is classified as a 'critical lift' under ASME B30.5?

The load weighs more than 10,000 lbs
The lift requires more than two rigging legs
The lift is performed indoors
The load exceeds 75% of the crane's rated capacity or involves unusual hazards (Correct answer)

Correct answer: The load exceeds 75% of the crane's rated capacity or involves unusual hazards

ASME B30.5 and most site standards classify a lift as critical when it exceeds 75% of rated capacity or presents exceptional hazards such as lifts over personnel or energized equipment.

Question 96: 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?

3 feet
6 feet
5 feet (Correct answer)
4 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 97: Under 1926.201, highway work zone signs, signals, and flagger practices must meet which standard?

ASME B30.5
ANSI Z359
NFPA 70E
The MUTCD (Manual on Uniform Traffic Control Devices) (Correct answer)

Correct answer: The MUTCD (Manual on Uniform Traffic Control Devices)

OSHA 1926.201 and 1926.202 incorporate FHWA's MUTCD Part 6 for temporary traffic control in work zones.

Question 98: What specific hazard does OSHA address in 29 CFR 1926.702 regarding bulk cement storage silos?

Engulfment hazard from entering an in-service silo (Correct answer)
Electrical grounding of metallic silos
Noise exposure from pneumatic cement conveyors
Silica dust exposure during silo loading

Correct answer: Engulfment hazard from entering an in-service silo

OSHA 1926.702(j) prohibits workers from entering bulk cement storage bins, tanks, or silos that are in service due to the engulfment hazard from flowing cement, which can bury a worker in seconds. This is analogous to grain entrapment in agriculture and is specifically addressed in the concrete subpart.

Question 99: What is the maximum allowable slope ratio for Type B soil in an excavation less than 20 feet deep?

1-1/2H:1V (Correct answer)
1H:1V
2H:1V
3/4H:1V

Correct answer: 1-1/2H:1V

Type B soil requires a maximum allowable slope of 1-1/2 horizontal to 1 vertical (53 degrees) for excavations under 20 feet.

Question 100: In a work zone, workers on foot are struck most often by which piece of equipment?

Backing vehicles and equipment (Correct answer)
Tower cranes
Scissor lifts
Concrete vibrators

Correct answer: Backing vehicles and equipment

BLS and NIOSH data show that backing dump trucks and other construction vehicles cause a large share of worker-on-foot struck-by deaths in work zones.

Question 101: Which type of fire extinguisher is appropriate for Class C (electrical) fires?

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

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 102: In a multi-employer construction worksite, OSHA's multi-employer citation policy can hold which types of employers liable?

The creating employer, the exposing employer, the correcting employer, and the controlling employer — each based on their specific role and responsibility (Correct answer)
Liability rests solely with the worker who committed the unsafe act
Only the subcontractor whose workers were exposed
Only the general contractor, who bears all safety liability on site

Correct answer: The creating employer, the exposing employer, the correcting employer, and the controlling employer — each based on their specific role and responsibility

OSHA's multi-employer citation policy can hold creating, exposing, correcting, and controlling employers each responsible for hazards based on their specific obligations and knowledge on a shared construction site.

Question 103: Which condition would allow a permit-required confined space to be reclassified as a non-permit confined space for entry?

All hazards within the space are eliminated or isolated before entry (Correct answer)
All workers complete confined space training
The space is ventilated for at least 30 minutes prior to entry
A safety officer monitors the space continuously

Correct answer: All hazards within the space are eliminated or isolated before entry

A permit space may be reclassified as non-permit only when all actual hazards have been eliminated or isolated and the space is verified safe by testing.

Question 104: What does the hierarchy of controls prescribe as the MOST effective method to reduce workplace hazards?

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

Correct answer: Elimination

Elimination—physically removing the hazard—is the most effective control measure in the hierarchy because it completely removes the risk.

Question 105: What is the PASS technique used for when operating a fire extinguisher?

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

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 106: A scaffold plank must extend beyond its support at least how many inches but no more than 18 inches?

6 inches (Correct answer)
9 inches
3 inches
12 inches

Correct answer: 6 inches

OSHA 1926.451 requires scaffold planks to overhang supports by at least 6 inches and no more than 18 inches.

Question 107: What is the primary purpose of a Safety and Health Management System (SHMS) on a construction project?

To set daily production targets for crews
To systematically identify, evaluate, and control hazards proactively (Correct answer)
To document incidents for insurance purposes
To satisfy OSHA recordkeeping requirements

Correct answer: To systematically identify, evaluate, and control hazards proactively

An SHMS provides a structured, proactive framework for identifying and controlling hazards before incidents occur, rather than reacting after the fact.

Question 108: Which class of fire extinguisher is specifically rated for energized electrical equipment fires?

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

Correct answer: Class C

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

Question 109: A new subcontractor arrives on site and will work near but not on equipment that is under lockout. What category does this worker fall under per OSHA 1910.147?

Other employee (Correct answer)
Affected employee
Qualified electrical worker
Authorized employee

Correct answer: Other employee

Workers who are not involved in servicing the equipment and not required to operate it are classified as 'other employees' and must be trained on the purpose and prohibition of LOTO.

Question 110: Which utility locating service must be contacted before excavation begins in the United States?

Local fire authority
OSHA area office
811 (Call Before You Dig) (Correct answer)
State labor department

Correct answer: 811 (Call Before You Dig)

Federal law requires contractors to contact 811 (the national call-before-you-dig number) to have underground utilities marked before any excavation.

Question 111: What is the required safe distance that unqualified workers must maintain from overhead power lines operating at 50kV on a construction site under OSHA 1926.416?

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

Correct answer: 15 feet

OSHA 1926.416 requires unqualified workers to stay at least 10 feet from lines up to 50kV; for 50kV, the distance increases to 15 feet.

Question 112: What is the purpose of an 'equipment-specific' LOTO procedure as opposed to a general LOTO procedure?

To provide step-by-step instructions tailored to a specific machine's energy sources and isolation points (Correct answer)
To satisfy recordkeeping requirements only
To authorize less-trained workers to perform lockout
To allow faster lockout without verifying zero energy

Correct answer: To provide step-by-step instructions tailored to a specific machine's energy sources and isolation points

Equipment-specific procedures document each energy source location, isolation method, and verification step unique to that machine, reducing human error during LOTO execution.

Question 113: A worker slips on spilled hydraulic fluid and fractures a wrist. Which barrier failed in this scenario according to barrier analysis?

Emergency response plan
Administrative control requiring gloves
Physical barrier preventing fluid from reaching the floor (Correct answer)
Permit-to-work system

Correct answer: Physical barrier preventing fluid from reaching the floor

Barrier analysis examines controls placed between a hazard and a target; here, a physical containment barrier (drip pan, berm, or housekeeping protocol) failed to prevent fluid accumulation on the walking surface.

Question 114: A worker is performing roofing work on a low-slope roof. Under OSHA 1926.502, a safety monitoring system used alone is only acceptable on low-slope roofs that are no wider than how many feet?

25 feet
75 feet
100 feet
50 feet (Correct answer)

Correct answer: 50 feet

A safety monitoring system alone is only permitted on low-slope roofs 50 feet or less in width. On roofs wider than 50 feet, a warning line system combined with a safety monitoring system or another form of fall protection must be used.

Question 115: Which of the following is a key requirement for storing excavated soil and other materials relative to the trench?

They must be stored uphill from the excavation.
They can be placed at the edge if a barricade is used.
They must be placed at least 2 feet from the edge. (Correct answer)
They must be hauled off-site by the end of each shift.

Correct answer: They must be placed at least 2 feet from the edge.

OSHA standard 1926.651(j)(2) requires that employees be protected from excavated or other materials or equipment that could pose a hazard by falling or rolling into excavations. Protection shall be provided by placing and keeping such materials or equipment at least 2 feet from the edge of the excavation.

Question 116: Which type of energy is specifically addressed by the term 'stored energy' in LOTO procedures?

Energy from active power generation
Residual energy such as capacitors, springs, or pressurized fluids (Correct answer)
Electrical energy in live circuits
Heat energy from external sources

Correct answer: Residual energy such as capacitors, springs, or pressurized fluids

Stored (residual) energy includes capacitor charge, compressed springs, pressurized hydraulics/pneumatics, and gravity potential that remain after the primary energy source is isolated.

Question 117: During demolition of a pre-1980 building, dust wipe samples reveal asbestos in joint compound. Under OSHA's asbestos construction standard, what is the excursion limit (EL) for short-term exposure?

1.0 f/cc averaged over 30 minutes (Correct answer)
2.0 f/cc averaged over 15 minutes
0.1 f/cc averaged over 30 minutes
0.5 f/cc averaged over 15 minutes

Correct answer: 1.0 f/cc averaged over 30 minutes

OSHA 29 CFR 1926.1101 sets the asbestos excursion limit at 1.0 fiber per cubic centimeter (f/cc) as a 30-minute short-term exposure limit.

Question 118: A 'fire watch' on a construction site is required to remain on duty for how long after hot work operations cease, per OSHA guidelines?

15 minutes
30 minutes (Correct answer)
Until the next shift
60 minutes

Correct answer: 30 minutes

OSHA requires a fire watch to be maintained for at least 30 minutes after hot work is completed to detect smoldering fires.

Question 119: What type of glove material provides the best chemical resistance when handling epoxy-based coatings on a construction site?

Latex gloves
Cotton liner gloves
Leather work gloves
Nitrile gloves (Correct answer)

Correct answer: Nitrile gloves

Nitrile gloves offer superior resistance to a broad range of chemicals including epoxies, solvents, and oils, making them the preferred choice for chemical handling on construction sites.

Question 120: A supervisor fails to report a recordable injury to the safety department for 10 days. Which OSHA standard is most likely violated?

29 CFR 1926.20 — General safety and health provisions
29 CFR 1904.32 — Annual summary
29 CFR 1904.29 — Forms (Correct answer)
29 CFR 1904.14 — Recording criteria for cases involving medical removal

Correct answer: 29 CFR 1904.29 — Forms

29 CFR 1904.29 requires that OSHA 300 Log entries be made within 7 calendar days of learning that a recordable incident occurred.

Question 121: What is the PRIMARY reason for maintaining written safety training records on a construction project?

To meet bonding requirements set by the project owner
To justify reduced insurance premiums at the end of the policy period
To provide evidence of corporate safety culture for marketing purposes
To document compliance with regulatory requirements and verify worker qualifications (Correct answer)

Correct answer: To document compliance with regulatory requirements and verify worker qualifications

Training records serve as objective evidence that the employer met legal obligations under applicable OSHA standards and that workers held the required competencies for their tasks. This documentation is critical during inspections, incident investigations, and litigation.

Question 122: An OSHA citation lists an abatement date. If the employer fails to correct the violation by that date, what may OSHA assess?

Failure-to-abate penalties for each day the violation continues (Correct answer)
Automatic criminal prosecution
Nothing, since the citation was already issued
A de minimis notice

Correct answer: Failure-to-abate penalties for each day the violation continues

Failure-to-abate penalties can be assessed for each calendar day the violation remains uncorrected beyond the abatement date.

Question 123: OSHA's multi-employer worksite doctrine affects safety communication by requiring which of the following?

Controlling, exposing, creating, and correcting employers each have communication and correction duties (Correct answer)
Only the general contractor is responsible for all worker safety communications
Subcontractor employees must attend only their own employer's safety meetings
Safety Data Sheets need only be shared with the prime contractor

Correct answer: Controlling, exposing, creating, and correcting employers each have communication and correction duties

OSHA's multi-employer policy assigns safety duties to multiple employer types based on their role, requiring coordinated cross-employer communication.

Question 124: The primary purpose of continuous forced-air ventilation in a permit-required confined space is to:

Replace and control hazardous atmospheres during occupancy (Correct answer)
Maintain temperature comfort for workers
Reduce the need for gas monitoring equipment
Eliminate the need for respiratory protection

Correct answer: Replace and control hazardous atmospheres during occupancy

Forced-air ventilation continuously dilutes and removes hazardous gases to maintain a safe atmosphere while workers occupy the space.

Question 125: When multiple contractors share a construction site, who bears the primary responsibility for coordinating the site-wide Emergency Action Plan?

OSHA's area office upon request
The general contractor or controlling employer (Correct answer)
The local fire authority having jurisdiction
Each subcontractor independently for their own crew

Correct answer: The general contractor or controlling employer

The general contractor, as the controlling employer, is responsible for coordinating a unified EAP across all subcontractors on a multi-employer site.

Question 126: What is the primary purpose of a Safety Data Sheet (SDS) Section 8 (Exposure Controls/Personal Protection)?

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

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 127: A construction site has 15 employees. An Emergency Action Plan (EAP) is required. Which of the following elements is a mandatory component of this plan according to 29 CFR 1926.35?

A list of all combustible materials stored on site.
The plan must only be communicated orally to all employees.
The home phone number of the company owner.
Procedures for employees who remain to operate critical equipment before they evacuate. (Correct answer)

Correct answer: Procedures for employees who remain to operate critical equipment before they evacuate.

According to 29 CFR 1926.35(b), an EAP must include several elements, one of which is 'Procedures to be followed by employees who remain to operate critical plant operations before they evacuate.' Because the site has more than 10 employees, the plan must be in writing and kept at the workplace.

Question 128: A construction site supervisor is developing a critical lift plan. Which of the following situations would OSHA define as a critical lift, requiring such a plan?

Using a brand new crane for the first time on a job site.
Any lift that occurs during nighttime hours.
A lift where the load is valued at over $100,000.
Lifting a load that exceeds 75% of the crane's rated capacity. (Correct answer)

Correct answer: Lifting a load that exceeds 75% of the crane's rated capacity.

OSHA defines a critical lift as one that exceeds 75% of the rated capacity of the crane or involves the use of more than one crane. While other factors may be included in a company's specific plan, exceeding 75% capacity is a primary OSHA trigger.

Question 129: Which chemical agent is prohibited for use in fighting fires involving reactive metals such as magnesium or titanium found on some construction sites?

Carbon dioxide (CO2)
Foam
Water (Correct answer)
Class D dry powder agent

Correct answer: Water

Water reacts violently with burning reactive metals, potentially causing explosions or spreading the fire; only Class D agents are appropriate.

Question 130: Under OSHA 29 CFR 1926.652, what is the maximum allowable slope for Type C soil when using the sloping method of protection?

0.75H:1V (53°)
1H:1V (45°)
1.5H:1V (34°) (Correct answer)
2H:1V (27°)

Correct answer: 1.5H:1V (34°)

Type C soil, the least stable classification, requires a slope of 1.5H:1V (approximately 34 degrees from horizontal).

Question 131: Which OSHA standard governs the use of personal protective equipment in construction, including requirements for employer-provided PPE?

29 CFR 1926.95 (Correct answer)
29 CFR 1926.59
29 CFR 1910.1000
29 CFR 1910.132

Correct answer: 29 CFR 1926.95

29 CFR 1926.95 is the OSHA construction industry standard specifically governing PPE requirements, including the employer's obligation to provide, maintain, and ensure proper use of required protective equipment on construction sites.

Question 132: What is the primary purpose of a trench box (shield) as a protective system?

To support adjacent structures above the trench
To prevent groundwater infiltration
To protect workers from cave-ins by shielding them, not preventing soil movement (Correct answer)
To classify the soil type before excavation

Correct answer: To protect workers from cave-ins by shielding them, not preventing soil movement

A trench shield (box) protects workers inside it from a cave-in but does not prevent soil movement — it provides a protected zone for workers to occupy.

Question 133: Under the multi-employer citation policy, the subcontractor whose crew removed guardrails and left them off is considered which type of employer?

Correcting employer
Creating employer (Correct answer)
Exposing employer
Controlling employer

Correct answer: Creating employer

The creating employer is the one that caused the hazardous condition and can be cited even if its own employees are not exposed.

Question 134: Which element is considered the foundation of an effective safety culture on a construction project?

Frequent OSHA inspections and citations
A comprehensive written safety plan exceeding 100 pages
Mandatory zero-tolerance disciplinary policies
Visible, consistent commitment to safety by senior management (Correct answer)

Correct answer: Visible, consistent commitment to safety by senior management

Research consistently shows that visible management commitment is the most critical driver of a positive safety culture.

Question 135: A safety program manager wants to improve supervisor accountability for safety. Which mechanism is MOST effective for embedding safety into supervisor performance expectations?

Requiring supervisors to attend monthly safety committee meetings
Issuing supervisors a copy of the updated site safety plan each quarter
Including measurable safety performance metrics in supervisor performance reviews and compensation (Correct answer)
Posting supervisor names on a safety scoreboard visible to all workers

Correct answer: Including measurable safety performance metrics in supervisor performance reviews and compensation

Tying safety metrics to performance reviews and compensation creates formal accountability and aligns supervisor incentives with safety outcomes.

Question 136: Which of the following conditions would require reclassifying Type A soil to a lower classification?

The excavation is less than 10 feet deep
Soil is completely dry
The soil is subject to vibration from heavy traffic (Correct answer)
Soil has been undisturbed for over a year

Correct answer: The soil is subject to vibration from heavy traffic

Vibration from heavy traffic or other sources can destabilize Type A soil, requiring it to be reclassified to Type B or Type C.

Question 137: Which document establishes minimum safety and health program requirements that are widely referenced by safety professionals and used as a framework for construction SMS?

ANSI/ASSP Z10 (Correct answer)
ACGIH TLV Handbook
NFPA 70E
OSHA 3132

Correct answer: ANSI/ASSP Z10

ANSI/ASSP Z10 is the American national standard for Occupational Health and Safety Management Systems, widely used as a construction SMS framework.

Question 138: How often must a competent person inspect excavations under OSHA 1926.651(k)?

Daily and after any event that could change conditions, such as rain, freezing temperatures, or vibration from nearby equipment (Correct answer)
Weekly
Once at the start of the project
Before each work shift only

Correct answer: Daily and after any event that could change conditions, such as rain, freezing temperatures, or vibration from nearby equipment

OSHA 1926.651(k)(1) requires a competent person to inspect excavations prior to each work shift, after rainstorms or other hazard-increasing events, and as needed throughout the shift.

Question 139: 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 II
Class IIIA

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 140: A safety technician discovers that workers are bypassing a lockout/tagout procedure. Which communication step should be taken FIRST?

File a formal written complaint with OSHA
Add the violation to the next monthly safety report
Discuss it at the annual safety review meeting
Immediately stop the work and conduct retraining on the proper LOTO procedure (Correct answer)

Correct answer: Immediately stop the work and conduct retraining on the proper LOTO procedure

Bypassing LOTO procedures creates an immediate life-threatening hazard requiring the work to be stopped and workers retrained before resuming the task.

Question 141: According to OSHA's recordkeeping rule (29 CFR 1904), which of the following work-related incidents is required to be recorded on the OSHA 300 Log?

A laborer requires a tetanus shot as a precaution after stepping on a nail.
An office worker at the construction trailer develops a headache.
A carpenter gets a splinter and removes it with tweezers.
A welder experiences a burn that is treated with two days of restricted work duty. (Correct answer)

Correct answer: A welder experiences a burn that is treated with two days of restricted work duty.

OSHA 29 CFR 1904.7 states that an injury or illness is recordable if it results in death, days away from work, restricted work, or transfer to another job. An injury resulting in restricted work duty meets this criterion. The other options are examples of first aid (splinter removal, tetanus shot) or are non-work-related/non-recordable symptoms without a diagnosis, and therefore are not required to be logged on the OSHA 300.

Question 142: What is the correct sequence for using a portable fire extinguisher, remembered by the acronym PASS?

Press, Aim, Squeeze, Spray
Pull, Aim, Sweep, Squeeze
Prepare, Activate, Spray, Secure
Pull, Aim, Squeeze, Sweep (Correct answer)

Correct answer: Pull, Aim, Squeeze, Sweep

PASS stands for Pull the pin, Aim at the base of the fire, Squeeze the handle, and Sweep side to side across the base of the flames.

Question 143: Which OSHA standard specifically governs confined spaces in construction?

29 CFR 1926 Subpart AA (1926.1200-1213) (Correct answer)
29 CFR 1910.146
29 CFR 1926.502
29 CFR 1926.650

Correct answer: 29 CFR 1926 Subpart AA (1926.1200-1213)

OSHA's 29 CFR 1926 Subpart AA (1926.1200-1213) specifically addresses confined spaces in construction, establishing requirements for permit spaces, entry procedures, training, and rescue.

Question 144: Which approach BEST demonstrates the hierarchy of controls when managing silica dust exposure during concrete cutting on a construction site?

Scheduling cutting operations during lunch breaks when fewer workers are present
Providing N95 respirators to all workers in the area
Using a wet-cutting method with integrated water suppression (Correct answer)
Posting warning signs around the cutting area

Correct answer: Using a wet-cutting method with integrated water suppression

Wet-cutting is an engineering control that eliminates silica dust at the source, which ranks higher on the hierarchy of controls than PPE, warnings, or administrative scheduling.

Question 145: What is the minimum height at which fall protection must be provided for workers in the construction industry according to OSHA standards?

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

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 146: When inspecting a full-body harness after a fall arrest event, the CORRECT action is:

Replace only the lanyard and re-certify the harness
Re-inspect and return to service if no visible damage is found
Send to manufacturer for inspection before reuse
Remove from service immediately and destroy or mark unusable (Correct answer)

Correct answer: Remove from service immediately and destroy or mark unusable

Any fall arrest equipment subjected to a fall event must be immediately removed from service and destroyed or clearly marked as unusable, regardless of visible damage.

Question 147: When earplugs and earmuffs are worn together, OSHA guidance estimates protection by adding how much to the higher NRR?

The full NRR of the lower device
10 dB
3 dB
5 dB (Correct answer)

Correct answer: 5 dB

Dual protection is estimated by adding 5 dB to the attenuation of the higher-rated device.

Question 148: 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 149: What is the minimum frequency required for inspecting portable fire extinguishers on a construction site under OSHA standards?

Annually
Weekly
Monthly (Correct answer)
Daily

Correct answer: Monthly

OSHA requires monthly visual inspections of portable fire extinguishers to ensure they are in place, fully charged, and operational.

Question 150: A crane operator receives conflicting hand signals from two workers during a lift. What should the operator do?

Follow the signal from the more experienced worker
Follow the signal from the worker closest to the load
Stop the crane and do not move until one designated signal person is identified (Correct answer)
Continue the lift at reduced speed until signals are clarified

Correct answer: Stop the crane and do not move until one designated signal person is identified

OSHA requires only one designated signal person per lift; receiving conflicting signals is a stop-work condition until a single signal person is confirmed.

Question 151: What is the minimum tensile strength required for each lanyard or vertical lifeline in a personal fall arrest system?

3,000 pounds
5,000 pounds (Correct answer)
10,000 pounds
7,500 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 152: When using the 5 Whys technique during a construction incident investigation, what indicates that the root cause has been reached?

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

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 153: What is the purpose of the GHS signal words 'Danger' and 'Warning' on chemical labels, and can both appear on the same label?

'Danger' applies only to flammable chemicals; 'Warning' applies only to toxic chemicals
'Danger' indicates more severe hazard categories; 'Warning' indicates less severe categories; only one signal word appears per label — if both would apply, 'Danger' takes precedence (Correct answer)
They are interchangeable and can be used on any hazardous chemical label
Both words must appear on every hazardous chemical label

Correct answer: 'Danger' indicates more severe hazard categories; 'Warning' indicates less severe categories; only one signal word appears per label — if both would apply, 'Danger' takes precedence

Under GHS, 'Danger' is used for more severe hazard categories and 'Warning' for less severe. Only one signal word appears per label — if multiple hazards apply, only 'Danger' is shown since it takes precedence.

Question 154: 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:

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

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 155: At what height must guardrail systems be installed on open-sided floors and platforms in general construction per OSHA standards?

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

Correct answer: 6 feet

OSHA 1926.502(b) requires guardrail systems when employees are exposed to falls of 6 feet or more to a lower level.

Question 156: Under OSHA 29 CFR 1910.147, which condition allows an employer to use an alternative to traditional lockout when equipment design does not allow for lockout?

A written tagout program with additional safety measures (Correct answer)
Verbal authorization from the supervisor
A safety observer stationed at the equipment
Posting warning signs within 6 feet of the energy source

Correct answer: A written tagout program with additional safety measures

When equipment cannot be locked out, OSHA allows tagout if the employer demonstrates equivalent protection through additional safety measures documented in a written program.

Question 157: During a confined space entry on a construction site, the attendant's PRIMARY role is to:

Perform continuous atmospheric monitoring from inside the space
Monitor the atmosphere inside the space and enter to assist if conditions worsen
Keep track of authorized entrants and initiate rescue procedures without entering (Correct answer)
Operate ventilation equipment to maintain safe oxygen levels

Correct answer: Keep track of authorized entrants and initiate rescue procedures without entering

The attendant must track entrants and initiate rescue (non-entry rescue or emergency services) but must NOT enter the permit space during an emergency.

Question 158: Under OSHA 1904.39, within what timeframe must employers report an in-patient hospitalization, amputation, or loss of an eye to OSHA?

Within 8 hours
Within 24 hours of learning about the event (Correct answer)
Within 72 hours
Within 3 business days

Correct answer: Within 24 hours of learning about the event

OSHA 1904.39(a)(2) requires employers to report in-patient hospitalizations, amputations, and loss of an eye to OSHA within 24 hours of learning about the incident — distinct from the 8-hour requirement for fatalities.

Question 159: Under 29 CFR 1910.1020, employee exposure records generally must be preserved for at least how long?

30 years (Correct answer)
5 years
10 years
Duration of employment

Correct answer: 30 years

Exposure records must be kept for at least 30 years because occupational diseases can have long latency periods.

Question 160: Which of the following BEST describes 'safety climate' as it relates to training effectiveness?

Workers' shared perceptions of how much management genuinely values safety (Correct answer)
The number of safety posters displayed in common areas
The outdoor temperature conditions under which safety training should be conducted
The frequency of OSHA inspections at a given site

Correct answer: Workers' shared perceptions of how much management genuinely values safety

Safety climate reflects workforce perceptions of management commitment; a positive climate amplifies training effectiveness while a negative one undermines it.

Question 161: What is the primary purpose of a fire watch on a construction site after hot work operations have been completed?

To inspect fire extinguisher maintenance tags
To supervise the hot work permit process
To train workers on evacuation procedures
To ensure no smoldering materials reignite after the work is finished (Correct answer)

Correct answer: To ensure no smoldering materials reignite after the work is finished

A fire watch monitors the area for at least 30 minutes after hot work to detect and extinguish any smoldering materials that could reignite.

Question 162: Which rigging configuration reduces a sling's rated capacity the most?

Choker hitch
Vertical hitch
Basket hitch at 60-degree included angle
Basket hitch at 30-degree included angle (Correct answer)

Correct answer: Basket hitch at 30-degree included angle

As the sling angle decreases from vertical, horizontal tension increases; a very narrow basket hitch (30° included angle) produces the greatest reduction in effective capacity.

Question 163: An employee files a complaint with OSHA and is demoted the following week. Under Section 11(c), within what period must the employee file a retaliation complaint?

180 days
15 days
30 days (Correct answer)
90 days

Correct answer: 30 days

Section 11(c) of the OSH Act requires retaliation complaints to be filed within 30 days of the adverse action.

Question 164: What is the primary purpose of a Job Hazard Analysis (JHA)?

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

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 165: A safety technician is reviewing heat stress controls for roofers working in July. Which engineering control has the highest hierarchy priority?

Scheduling heavy work during cooler morning hours
Requiring workers to drink 1 cup of water every 20 minutes
Installing shade structures over the work area (Correct answer)
Providing personal cooling vests for each worker

Correct answer: Installing shade structures over the work area

Installing shade structures is an engineering control, which ranks higher in the hierarchy of controls than administrative (scheduling) or PPE (cooling vests, hydration) measures.

Question 166: During a concrete pour, a form suddenly bulges outward at the base. The FIRST corrective action should be:

Notify the engineer and await instructions before stopping the pour
Continue the pour and add wedges to the outside of the form
Stop the pour immediately and evacuate workers from the affected area (Correct answer)
Reduce the concrete pump pressure and continue at a slower rate

Correct answer: Stop the pour immediately and evacuate workers from the affected area

Form bulging indicates imminent failure from excess lateral pressure. The immediate priority is life safety — stop the pour and evacuate all personnel from the hazard zone. Continuing the pour at any rate risks progressive collapse. Engineering consultation follows evacuation, not precedes it.

Question 167: Two identical compressors each produce 88 dBA at a worker's position. What is the approximate combined level?

91 dBA (Correct answer)
176 dBA
88 dBA
94 dBA

Correct answer: 91 dBA

Decibels add logarithmically, so two equal sources increase the level by about 3 dB.

Question 168: What are the key components of an effective Safety and Health Management System (SHMS) audit?

An OSHA inspection conducted by a federal compliance officer
An annual review of the OSHA 300 Log and incident reports only
A quarterly safety committee meeting with management review
Document review, employee interviews, field observations, and a corrective action plan with assigned owners and completion dates (Correct answer)

Correct answer: Document review, employee interviews, field observations, and a corrective action plan with assigned owners and completion dates

An effective SHMS audit uses document review, interviews, and field observations to identify gaps against established criteria, producing findings and a corrective action plan with assigned responsibilities.

Question 169: What is the minimum approach distance for an unqualified worker near exposed energized parts operating at 50 kV on a construction site per OSHA 1926 Subpart K?

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

Correct answer: 10 feet

OSHA 1926.416 requires unqualified workers to maintain at least 10 feet from exposed energized conductors or parts rated up to 50 kV.

Question 170: When is reshoring required after stripping forms?

When necessary to safely support slabs and beams after stripping or when subjected to superimposed loads (Correct answer)
Only for precast elements
Never, once forms are removed
Only during winter concreting

Correct answer: When necessary to safely support slabs and beams after stripping or when subjected to superimposed loads

Reshoring must be provided when necessary to safely support slabs and beams after stripping or under superimposed loads.

Question 171: Which hazard control measure represents the highest level of protection in the hierarchy of controls when addressing airborne chemical hazards on a construction site?

Substituting a less hazardous chemical for the one in use (Correct answer)
Installing local exhaust ventilation at the point of generation
Providing workers with supplied-air respirators
Implementing administrative rotation schedules to limit exposure time

Correct answer: Substituting a less hazardous chemical for the one in use

Substitution — replacing a hazardous substance with a less harmful alternative — ranks above all other controls in the hierarchy because it eliminates or fundamentally reduces the hazard at the source. Engineering controls like ventilation, administrative controls, and PPE all manage exposure to an existing hazard rather than removing it.

Question 172: What should be the first action of a construction worker who discovers a fire that cannot be immediately controlled with a portable extinguisher?

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

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

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

Correct answer: Blue (left)

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

Question 174: Which of the following best describes a 'contributing cause' in incident investigation terminology?

A condition that increased the likelihood or severity of the incident but alone would not have caused it (Correct answer)
The single factor that directly caused the incident
The unsafe act committed by the injured worker
An administrative failure that is always preventable

Correct answer: A condition that increased the likelihood or severity of the incident but alone would not have caused it

A contributing cause is a factor that worsened or enabled the incident but is distinguished from the direct cause by the fact that it alone was insufficient to produce the outcome.

Question 175: A construction worker develops redness, itching, and blistering after contact with uncured epoxy resin. This reaction is BEST classified as:

Chemical burn
Irritant contact dermatitis
Allergic contact dermatitis (Correct answer)
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 176: A safety technician observes workers using a powder-actuated tool without wearing hearing protection. Under OSHA standards, this tool requires hearing protection because noise levels typically exceed:

90 dBA (Correct answer)
100 dBA
85 dBA
140 dBA

Correct answer: 90 dBA

OSHA's 1926.52 action level is 90 dBA for an 8-hour TWA; powder-actuated tools often exceed this threshold.

Question 177: During a toolbox talk, a foreman asks which class of hard hat protects against high-voltage electrical hazards up to 20,000 volts. The correct answer is:

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

Correct answer: Class B

Class B (Type II) hard hats are tested to protect against high-voltage electrical hazards up to 20,000 volts.

Question 178: A NIOSH Lifting Index (LI) of 2.4 for a block-laying task indicates what?

The worker may lift 2.4 times per minute safely
The load is 2.4 lb above the load constant
The task carries elevated risk of lifting-related low back pain for many workers (Correct answer)
The task is acceptable for nearly all healthy workers

Correct answer: The task carries elevated risk of lifting-related low back pain for many workers

LI is load weight divided by RWL, and values above 1.0 show increased risk, rising as LI goes up.

Question 179: Which type of lanyard is designed to reduce peak fall arrest forces by absorbing energy during its deployment?

Shock-absorbing lanyard (Correct answer)
Rope grab lanyard
Self-retracting lifeline
Single-leg lanyard

Correct answer: Shock-absorbing lanyard

Shock-absorbing lanyards contain a tear-web or similar device that rips open during a fall, dissipating energy and reducing the peak arresting force transmitted to the worker's body.

Question 180: Under OSHA's fall protection standards for construction, which activity has a fall protection trigger height of 6 feet?

Precast concrete erection
Excavation work
Leading edge work (Correct answer)
Bridge inspection

Correct answer: Leading edge work

Leading edge work falls under the general construction fall protection trigger of 6 feet per 29 CFR 1926.502.

Question 181: During a construction site emergency evacuation, who is typically responsible for accounting for all workers at the assembly point?

Each individual worker independently
The project owner's representative
The designated crew supervisor or foreman (Correct answer)
The site safety officer

Correct answer: The designated crew supervisor or foreman

Crew supervisors or foremen are typically assigned headcount accountability at assembly areas during evacuations.

Question 182: What is the OSHA permissible exposure limit (PEL) for silica (respirable crystalline) in construction under 29 CFR 1926.1153?

25 µg/m³ as an 8-hour TWA
50 µg/m³ as an 8-hour TWA (Correct answer)
250 µg/m³ as an 8-hour TWA
100 µg/m³ as an 8-hour TWA

Correct answer: 50 µg/m³ as an 8-hour TWA

OSHA's PEL for respirable crystalline silica in construction is 50 µg/m³ as an 8-hour time-weighted average.

Question 183: Mobile equipment is working next to an excavation, and the operator cannot clearly see the edge. What does OSHA require?

Lowering the equipment's speed limit to 5 mph
A warning system such as barricades, hand or mechanical signals, or stop logs (Correct answer)
Moving all workers out of the excavation for the whole shift
An extra competent person inspection each hour

Correct answer: A warning system such as barricades, hand or mechanical signals, or stop logs

1926.651(f) requires a warning system when the operator does not have a clear and direct view of the excavation edge.

Question 184: Why is a pinch grip riskier than a power grip for repetitive tasks?

A pinch grip uses larger muscles
A pinch grip reduces contact stress
A pinch grip produces much less force, so the tendons work harder for the same load (Correct answer)
A pinch grip eliminates wrist deviation

Correct answer: A pinch grip produces much less force, so the tendons work harder for the same load

A pinch grip produces only a fraction of power-grip strength, which raises tendon load for the same task.

Question 185: Under 1926.706, how large must the limited access zone be when a masonry wall is under construction?

Twice the wall height
The wall height plus 4 feet (Correct answer)
Equal to the wall height
10 feet regardless of wall height

Correct answer: The wall height plus 4 feet

The limited access zone must equal the height of the wall plus 4 feet and run the full length of the wall on the unscaffolded side.

Question 186: What is the purpose of a toeboard on a scaffold platform?

To prevent tools and materials from falling to lower levels (Correct answer)
To anchor the guardrail post
To mark the edge of the platform for visibility
To provide a foothold for climbing

Correct answer: To prevent tools and materials from falling to lower levels

Toeboards on scaffold platforms prevent tools, materials, and debris from rolling or falling off the edge to workers below.

Question 187: When evaluating a construction site's safety program, a CHST finds the experience modification rate (EMR) is 1.35. What does this indicate?

The company is exempt from OSHA inspections
The company qualifies for safety incentive bonuses
The company's workers' comp costs are 35% above industry average (Correct answer)
The company has 35% fewer injuries than average

Correct answer: The company's workers' comp costs are 35% above industry average

An EMR above 1.0 indicates a worse-than-average injury history; 1.35 means costs are approximately 35% higher than the industry average.

Question 188: Under OSHA 29 CFR 1926.52, what is the permissible exposure limit (PEL) for occupational noise averaged over an 8-hour workday?

90 dBA TWA (Correct answer)
95 dBA TWA
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 189: What is the OSHA-defined action level for noise exposure that triggers a hearing conservation program?

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

Correct answer: 85 dBA TWA

At 85 dBA TWA (the action level), employers must implement a hearing conservation program including audiometric testing and hearing protection availability.

Question 190: What is the required height range for a standard guardrail top rail on a construction site per OSHA 1926.502?

Exactly 42 inches
Between 39 and 45 inches (Correct answer)
At least 36 inches
Between 36 and 48 inches

Correct answer: Between 39 and 45 inches

OSHA 1926.502(b)(1) specifies that top rails must be installed between 39 and 45 inches above the walking/working surface to properly protect workers from falls.

Question 191: Scaffold planks must extend beyond their end supports by a minimum of:

6 inches (Correct answer)
18 inches
12 inches
3 inches

Correct answer: 6 inches

Scaffold planks must extend at least 6 inches beyond their supports to prevent tipping.

Question 192: 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 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
Hot Work Permits are only required when working near sprinkler systems
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)

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 193: 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
Swiss cheese model
Pareto principle

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 194: What is the NIOSH position on using back belts to prevent lifting injuries?

They work as well as mechanical lifting aids
There is not enough scientific evidence to recommend them as an injury-prevention measure (Correct answer)
They are recommended for all workers lifting over 25 lb
They are required by OSHA for manual material handling

Correct answer: There is not enough scientific evidence to recommend them as an injury-prevention measure

NIOSH found insufficient evidence that back belts reduce back injuries and does not recommend them as a control.

Question 195: A project safety manager is developing a subcontractor prequalification process. Which criterion is MOST relevant to safety program effectiveness?

The subcontractor's proximity to the project site
Whether the subcontractor uses union or non-union labor
Subcontractor's three-year TRIR and DART rates compared to industry averages (Correct answer)
Number of employees on the subcontractor's payroll

Correct answer: Subcontractor's three-year TRIR and DART rates compared to industry averages

TRIR and DART rates provide objective, industry-benchmarked evidence of a subcontractor's historical safety performance.

Question 196: In the revised NIOSH Lifting Equation, what is the load constant used to calculate the Recommended Weight Limit (RWL)?

50 lb (22.7 kg)
51 lb (23 kg) (Correct answer)
35 lb (16 kg)
60 lb (27 kg)

Correct answer: 51 lb (23 kg)

The revised NIOSH equation starts from a 51 lb (23 kg) load constant, which the task multipliers then reduce.

Question 197: What is the required minimum height for the top edge of a guardrail system used in construction?

48 inches
36 inches
42 inches (Correct answer)
39 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 198: A worker refuses to perform a task they believe is imminently dangerous. Under the OSH Act, the employer:

Cannot discipline the worker for refusing work they reasonably believe poses imminent danger of death or serious injury (Correct answer)
Can require the worker to perform the task while additional PPE is sourced
May terminate the worker immediately for insubordination
Must report the worker's refusal to OSHA within 24 hours

Correct answer: Cannot discipline the worker for refusing work they reasonably believe poses imminent danger of death or serious injury

The OSH Act's Section 11(c) protects workers from retaliation for refusing imminently dangerous work when a reasonable person would agree the danger exists.

Question 199: A drum labeled with a UN/DOT hazard class 3 placard contains which category of material?

Oxidizers
Corrosive liquids
Toxic gases
Flammable liquids (Correct answer)

Correct answer: Flammable liquids

DOT Hazard Class 3 designates flammable liquids, including gasoline, acetone, and similar solvents commonly found on construction sites.

Question 200: A safety technician is tasked with improving the company's incident investigation process. Which change would have the GREATEST impact on preventing future incidents?

Completing investigation reports within 24 hours
Requiring all investigations to be reviewed by legal counsel
Increasing the number of photographs taken at incident scenes
Identifying root causes rather than only immediate causes (Correct answer)

Correct answer: Identifying root causes rather than only immediate causes

Root cause analysis addresses the systemic failures that allow incidents to occur, leading to corrective actions that prevent recurrence rather than just treating symptoms.

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

Checking for saved progress...

Exam Rules

You can skip questions and return to them later
Flag questions for review before submitting
No feedback shown until you submit the entire exam
Unanswered questions count as wrong — answer everything
10 pretest questions are mixed in and don't affect your score
Timer auto-submits when time runs out
Your progress is auto-saved every 30 seconds

These practice questions were written with AI tools. They are not real exam questions. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy

Sources & references

Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy

bcsp.org — Test delivery, eligibility, fees, renewal, retake policy, test dates, time limit · verified Sep 2026