Free Certified Industrial Hygienist (CIH) General Questions and Answers — Questions and Answers

Question 1: Although this measurement doesn't always indicate how much of a chemical will be absorbed, it does indicate how much can be inhaled throughout the course of a workday:

Threshold Limit Value (TLV)
Time Weighted Average (TWA) (Correct answer)
Ceiling Value (CV)
Permissible Exposure Limit (PEL)

Correct answer: Time Weighted Average (TWA)

The Time Weighted Average (TWA) is a common metric used in industrial hygiene to represent an average exposure to a hazardous substance over a specific period, typically an 8-hour workday. It indicates the average concentration of a substance in the air that a worker can inhale over that period. While it quantifies inhalation exposure, it doesn't directly account for absorption through other routes like skin contact, which is why it doesn't always indicate total absorbed dose.

Question 2: All of the following areas of study are carried out to identify potential adverse effects on the musculoskeletal system, WITH THE EXCEPTION of:

incentive pay systems
group dynamics (Correct answer)
performance monitoring
production demands

Correct answer: group dynamics

Ergonomic studies and assessments aim to identify factors that contribute to musculoskeletal disorders (MSDs). Incentive pay systems, performance monitoring, and production demands can all influence work pace, posture, repetition, and force, thereby directly impacting the musculoskeletal system. Group dynamics, while important for team cohesion and psychological well-being, is generally not a direct factor studied for its adverse effects on the physical musculoskeletal system in ergonomics.

Question 3: Each of the following, EXCEPT:, is a significant goal of the science of epidemiology, according to Leon Gordis.

Evaluate existing and new therapeudic and preventive measures
To determine effects of toxins on control populations of animals (Correct answer)
To discover the etiology of an occupational disease,
Determine the extent to which the disease if found in the workplace

Correct answer: To determine effects of toxins on control populations of animals

Epidemiology is the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems. Its goals, as described by Leon Gordis, include discovering disease etiology, determining disease extent, and evaluating interventions in human populations. Determining effects of toxins on *control populations of animals* falls under toxicology or experimental research, not the primary domain of human epidemiology.

Question 4: This illness is brought on by being in an atmosphere where the body cannot adequately cool itself, right?

heat cramps
heatstroke (Correct answer)
heat stress
heat exhaustion

Correct answer: heatstroke

Heatstroke is the most severe heat-related illness and a medical emergency. It occurs when the body's temperature regulation system fails, leading to a dangerously high core body temperature (typically above 104°F or 40°C) and the inability to cool itself. This failure to adequately cool results in central nervous system dysfunction and can be fatal if not treated immediately.

Question 5: All of the following should be known to, and all competent individuals in charge of scaffold work should be capable of identifying and correcting hazards associated to them, EXCEPT:

fall protection
scaffold assembly
structural integrity
soil conditions (Correct answer)

Correct answer: soil conditions

A competent person for scaffold work, as defined by OSHA, must be knowledgeable about the specific hazards associated with scaffold construction, use, and dismantling. This includes understanding fall protection, proper scaffold assembly, and ensuring structural integrity. While soil conditions are crucial for proper scaffold foundation and stability, they are typically assessed by a competent person for *foundations* or *excavations*, not necessarily the *scaffold competent person* themselves, whose primary focus is the scaffold structure and its immediate safety.

Question 6: Every toxicological evaluation is based on the:

toxicological relationship
dosage-toxic constant
dose-response relationship (Correct answer)
toxic-absorption constant

Correct answer: dose-response relationship

The dose-response relationship is a fundamental concept in toxicology. It describes the correlation between the exposure (dose) to a substance and the observed effects (response) in an organism. Understanding this relationship is crucial for determining safe exposure limits, assessing toxicity, and predicting the health outcomes of different levels of exposure to a chemical.

Question 7: The following factors affect how adequate and effective lighting is, WITH THE EXCEPTION OF:

freedom from glare
freedom from diffusion
freedom from glare
freedom from concentration (Correct answer)

Correct answer: freedom from concentration

Effective lighting design aims to provide sufficient illumination without causing discomfort or visual strain. Key factors include freedom from glare (excessive brightness), proper diffusion (even spread of light), and adequate intensity. "Freedom from concentration" is not a recognized factor in lighting adequacy; rather, lighting should allow for visual concentration on tasks, not be free from it.

Question 8: Each of the following, EXCEPT:, is a significant goal of the science of epidemiology, according to Leon Gordis.

To discover the etiology of an occupational disease,
To provide a foundation for developing regulations
Evaluate the degree to which occupational disease impacts productivity (Correct answer)
Determine the extent to which the disease if found in the workplace

Correct answer: Evaluate the degree to which occupational disease impacts productivity

According to Leon Gordis and general epidemiological principles, the primary goals of epidemiology include discovering disease etiology, determining disease extent in populations, and evaluating preventive and therapeutic measures. While occupational diseases can certainly impact productivity, evaluating this specific economic impact is typically a secondary application or an outcome measure, not a core, significant goal of the *science* of epidemiology itself. Epidemiology focuses on health outcomes, not directly on economic productivity.

Question 9: How much nitrogen and other inert gases are typically present in the atmosphere at sea level?

79 percent (Correct answer)
42 percent
32 percent
21 percent

Correct answer: 79 percent

The Earth's atmosphere at sea level is primarily composed of nitrogen, which makes up approximately 78% to 79% of the total volume. Oxygen accounts for about 21%, and the remaining 1% consists of argon and trace amounts of other inert gases like neon, helium, krypton, and xenon. Therefore, 79% accurately represents the combined proportion of nitrogen and other inert gases.

Question 10: Through the plans and specifications, this role defines the arrangement and elements of the work:

designer (Correct answer)
originator
planner
coordinating engineer

Correct answer: designer

The designer is the role responsible for translating conceptual ideas into detailed plans and specifications for a project. This involves defining the specific arrangement, components, materials, and overall elements of the work, providing the blueprint for its execution. Other roles like originator, planner, or coordinating engineer have different primary responsibilities in a project lifecycle.

Question 11: The risks associated with ____ are to blame for the majority of job injuries and physical ailments.

radiation
noise
ergonomics (Correct answer)
machine guarding

Correct answer: ergonomics

Ergonomics is the science of designing the workplace, equipment, and tasks to fit the worker, aiming to reduce physical stress and improve productivity. Poor ergonomic design is a leading cause of musculoskeletal disorders (MSDs), such as back injuries, carpal tunnel syndrome, and tendonitis, which account for the vast majority of job-related injuries and physical ailments across industries. Addressing ergonomic risks is crucial for worker health and safety.

Question 12: A competent individual at an excavation site should be aware of, and be able to recognize and address hazards associated with, ALL OF THE FOLLOWING, EXCEPT:

shoring requirements
biological hazards (Correct answer)
water removal equipment
hazardous atmospheres

Correct answer: biological hazards

A competent individual at an excavation site is primarily focused on hazards directly related to the structural integrity and atmospheric conditions of the excavation. This includes understanding shoring requirements to prevent cave-ins, managing water accumulation, and identifying hazardous atmospheres like oxygen deficiency or toxic gases. While biological hazards might exist in the general environment, they are not typically a primary, inherent hazard that a competent person specifically addresses as part of excavation safety protocols, unlike the immediate structural and atmospheric risks.

Question 13: Which of the following is not something a successful ergonomics job hazard analysis would ever do?

exclude employee involvement in the analysis (Correct answer)
identify conditions contributing to risk factors
measure and quantify ergonomic risk factors
break down task into individual steps

Correct answer: exclude employee involvement in the analysis

A successful ergonomics job hazard analysis critically relies on the active involvement of employees who perform the tasks. Excluding employee input would lead to an incomplete and inaccurate understanding of actual work practices, perceived difficulties, and potential solutions. Workers' firsthand experience is invaluable for identifying specific risk factors and developing practical, effective interventions.

Question 14: What metrics are being used to establish Threshold Limit Values (TLV)?

anywhere in the workplace
within eight feet of the work zone
generally where work is being conducted
within the breathing zone of a worker (Correct answer)

Correct answer: within the breathing zone of a worker

Threshold Limit Values (TLVs) are occupational exposure limits for airborne contaminants, representing concentrations to which nearly all workers can be exposed daily without adverse health effects. To accurately assess a worker's exposure relative to these limits, air samples must be collected within the 'breathing zone,' which is the immediate area around the worker's nose and mouth, as this directly reflects the air they inhale.

Question 15: Between __ Hz, the body will respond to vertical vibration most strongly:

10 and 12
2 and 4
4 and 8 (Correct answer)
8 and 10

Correct answer: 4 and 8

The human body has natural resonant frequencies where it is most susceptible to vibration. For whole-body vertical vibration, the most sensitive range, where internal organs and structures resonate most strongly, is generally between 4 and 8 Hz. Exposure to vibration within this frequency range can lead to significant discomfort, fatigue, and potential health issues over time.

Question 16: This approach to assessing hazards' types and severity looks at population-based study literature to learn more about potentially harmful health consequences that haven't been identified in a small workforce:

Interviews and maintenance activities
Process or operation analysis
Variability of response
Epidemiolgical and risk assessment (Correct answer)

Correct answer: Epidemiolgical and risk assessment

The epidemiological and risk assessment approach involves studying patterns and causes of health effects in populations. By reviewing population-based study literature, this method helps identify potentially harmful health consequences (e.g., long-term diseases) that might not yet be evident or statistically significant in a smaller, specific workforce due to latency periods or insufficient sample size. Risk assessment then quantifies the likelihood and severity of these identified hazards.

Free Certified Industrial Hygienist (CIH) General Questions and Answers

Although this measurement doesn't always indicate how much of a chemical will be absorbed, it does indicate how much can be inhaled throughout the course of a workday: