100+ Free CAIH Practice Questions

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Question 1

Score: 0/0

The ACGIH TLV-STEL represents a maximum exposure for what time period?

30 minutes

1 hour

15 minutes

8 hours

to track

2026 Statistics

Key Facts: CAIH Exam

180 Qs

Exam Questions

150 scored + 30 pilot

70%

Passing Score

126 correct answers

5 hrs

Time Limit

Two 2.5-hour sessions

35 pts

CM Points per Cycle

5-year recertification

The CAIH exam had 180 multiple-choice questions (150 scored, 30 pilot) with a 5-hour time limit and a 70% passing score. The exam was offered 2001-2006; the credential is still maintained through BGC recertification. Key content areas include air sampling and instrumentation, toxicology, chemical hazards, ventilation and engineering controls, noise assessment, and personal protective equipment. CAIH holders must earn 35 CM points every 5 years to maintain certification.

Sample CAIH Practice Questions

Try these sample questions to test your CAIH exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1What is the primary purpose of industrial hygiene?

A.Maximizing worker productivity through ergonomic design

B.Anticipating, recognizing, evaluating, and controlling workplace health hazards

C.Enforcing OSHA regulations at the federal level

D.Treating occupational diseases after diagnosis

Explanation: Industrial hygiene is defined as the science and art of anticipating, recognizing, evaluating, and controlling workplace environmental factors or stresses that may cause sickness, impaired health, or significant discomfort among workers. This encompasses chemical, physical, biological, and ergonomic hazards.

2Which of the following is the correct order of the hierarchy of controls from most to least effective?

A.PPE, administrative controls, engineering controls, substitution, elimination

B.Elimination, substitution, engineering controls, administrative controls, PPE

C.Engineering controls, elimination, substitution, PPE, administrative controls

D.Substitution, elimination, engineering controls, PPE, administrative controls

Explanation: The hierarchy of controls ranks hazard control methods from most to least effective: elimination removes the hazard entirely, substitution replaces it with something less hazardous, engineering controls isolate workers from the hazard, administrative controls change how work is done, and PPE is the last resort providing a barrier on the worker.

3Which route of entry is the most common for occupational exposure to chemical hazards?

A.Ingestion

B.Injection

C.Inhalation

D.Dermal absorption

Explanation: Inhalation is the most common and significant route of occupational chemical exposure. The lungs provide a large surface area for absorption, and airborne contaminants in the workplace are readily breathed in during normal work activities. This is why air monitoring is a fundamental industrial hygiene practice.

4What does the acronym PEL stand for in the context of OSHA regulations?

A.Protective Exposure Level

B.Permissible Exposure Limit

C.Personal Exposure Limit

D.Predicted Effect Level

Explanation: PEL stands for Permissible Exposure Limit, which is a legally enforceable standard set by OSHA under 29 CFR 1910.1000. PELs represent the maximum amount or concentration of a chemical that a worker may be exposed to, typically expressed as an 8-hour time-weighted average (TWA).

5An industrial hygienist measures a worker's noise exposure at 90 dBA over an 8-hour shift. According to OSHA's Hearing Conservation Standard, what action is required?

A.No action needed — this is below the action level

B.Include the worker in a hearing conservation program

C.Immediately remove the worker from the noise area

D.Issue a citation to the employer

Explanation: OSHA's Hearing Conservation Amendment (29 CFR 1910.95) requires employers to implement a hearing conservation program when workers are exposed to an 8-hour TWA of 85 dBA or above (the action level). At 90 dBA TWA, the PEL is reached, requiring enrollment in a hearing conservation program including audiometric testing, hearing protectors, training, and recordkeeping.

6Which type of air sampling collects a contaminant on a filter or sorbent tube over a defined period?

A.Grab sampling

B.Direct-reading sampling

C.Integrated sampling

D.Biological sampling

Explanation: Integrated sampling involves drawing air through a collection medium (filter, sorbent tube, or impinger) over a defined time period using a calibrated personal sampling pump. The collected sample is then sent to a laboratory for analysis. This method provides a time-weighted average concentration over the sampling period.

7What is the OSHA Permissible Exposure Limit (PEL) for airborne asbestos fibers?

A.0.5 fibers per cubic centimeter (f/cc)

B.0.1 fibers per cubic centimeter (f/cc)

C.1.0 fibers per cubic centimeter (f/cc)

D.2.0 fibers per cubic centimeter (f/cc)

Explanation: OSHA's PEL for asbestos is 0.1 fibers per cubic centimeter (f/cc) as an 8-hour TWA, established in 29 CFR 1910.1001 (general industry) and 29 CFR 1926.1101 (construction). The excursion limit (STEL) is 1.0 f/cc averaged over 30 minutes.

8A personal sampling pump must be calibrated before and after each use. What is the acceptable variation between pre- and post-calibration flow rates?

A.Within 1%

B.Within 5%

C.Within 10%

D.Within 15%

Explanation: NIOSH and OSHA guidelines generally require that the pre- and post-calibration flow rates agree within ±5%. If the difference exceeds 5%, the sample may be considered invalid. Calibration is typically performed using a primary standard such as a soap bubble meter or electronic flow calibrator.

9Which of the following correctly describes a dose-response relationship?

A.As the dose of a substance increases, the response always decreases

B.As the dose of a substance increases, the magnitude or incidence of a biological response generally increases

C.The dose of a substance has no relationship to the biological response

D.A fixed dose always produces the same response in all individuals

Explanation: The dose-response relationship is a fundamental principle in toxicology stating that as the dose (amount of exposure) increases, the magnitude or incidence of a toxic effect generally increases. This relationship is often depicted as a sigmoid curve and forms the basis for establishing occupational exposure limits.

10What is the purpose of a local exhaust ventilation (LEV) system?

A.To provide fresh air to the entire building through HVAC systems

B.To capture contaminants at or near the source before they disperse into the work area

C.To increase air velocity throughout the entire workspace

D.To filter outdoor air before it enters the building

Explanation: Local exhaust ventilation captures airborne contaminants at or near the point of generation, preventing them from entering the worker's breathing zone. LEV systems consist of a hood, ductwork, air-cleaning device, fan, and exhaust stack. They are more effective and energy-efficient than general dilution ventilation for controlling specific contaminant sources.

About the CAIH Exam

The CAIH credential was established by the Board for Global EHS Credentialing (formerly ABIH) for industrial hygiene professionals working in narrow-scope or multi-disciplinary roles. The exam focused on hazard recognition and evaluation rather than comprehensive program management, covering air sampling, toxicology, chemical and physical hazards, ventilation, noise, radiation, and PPE selection.

Questions

180 scored questions

Time Limit

5 hours

Passing Score

70% (126 of 180)

Exam Fee

$350 + $160 application fee (BGC (Pearson VUE))

CAIH Exam Content Outline

15%

Air Sampling & Instrumentation

Sampling strategies, direct-reading instruments, calibration, passive and active sampling, and quality assurance.

12%

Toxicology

Dose-response, routes of exposure, acute and chronic effects, target organ toxicity, and occupational exposure limits.

12%

Chemical Hazards

Recognition and evaluation of gases, vapors, dusts, fumes, mists, and organic solvents in workplace environments.

12%

Ventilation & Engineering Controls

Local exhaust ventilation, dilution ventilation, hood design, duct calculations, and capture velocity.

10%

Noise & Vibration

Sound measurement, noise dosimetry, audiometric testing, hearing conservation, and vibration assessment.

10%

Non-Engineering Controls & PPE

Respiratory protection, PPE selection criteria, administrative controls, and hierarchy of controls.

Radiation

Ionizing and non-ionizing radiation hazards, measurement, exposure limits, and shielding strategies.

Biological Hazards

Mold, bacteria, viruses, bloodborne pathogens, and biological sampling methods.

Thermal Stressors

Heat stress (WBGT), cold stress, acclimatization protocols, and physiological monitoring.

Ergonomics

Musculoskeletal risk assessment, workplace design, lifting guidelines, and ergonomic tools.

Analytical Chemistry

Sampling media selection, laboratory analysis, detection limits, chain of custody, and QA/QC.

How to Pass the CAIH Exam

What You Need to Know

Passing score: 70% (126 of 180)
Exam length: 180 questions
Time limit: 5 hours
Exam fee: $350 + $160 application fee

Keys to Passing

Complete 500+ practice questions
Score 80%+ consistently before scheduling
Focus on highest-weighted sections
Use our AI tutor for tough concepts

CAIH Study Tips from Top Performers

1Focus on air sampling techniques — know the difference between active and passive sampling, direct-reading instruments, and integrated sampling methods.

2Master OSHA PELs, NIOSH RELs, and ACGIH TLVs — understand how to compare sampling results to these occupational exposure limits.

3Study the hierarchy of controls in order: elimination, substitution, engineering controls, administrative controls, and PPE.

4Practice ventilation calculations including capture velocity, duct velocity, hood static pressure, and transport velocity for particulates.

5Review toxicology fundamentals: dose-response curves, LD50/LC50, routes of entry (inhalation, dermal, ingestion), and target organ effects.

Frequently Asked Questions

Is the CAIH exam still available?

The CAIH exam was discontinued in 2006 due to low demand. However, the CAIH designation is still recognized and supported by the Board for Global EHS Credentialing (BGC) through its certification maintenance program. Existing CAIH holders can maintain their credential by earning 35 CM points every 5 years and paying annual fees.

What is the difference between CAIH and CIH?

The CAIH was designed for specialists and multi-disciplinary professionals working in narrow-scope industrial hygiene roles, while the CIH is for broad-scope practitioners. The CAIH focused on hazard recognition and evaluation with less formal science prerequisites, whereas the CIH covers comprehensive practice including program management and requires 60 STEM semester hours.

How do I maintain my CAIH certification?

CAIH holders must earn 35 CM (Certification Maintenance) points during each 5-year cycle, including at least 10 points in industrial hygiene education and 0.33 points (2 hours) in ethics. Points are earned at a rate of 0.167 per hour of professional development. An annual fee of $150 is required, and 5% of diplomates are audited each cycle.

Can CAIH holders upgrade to CIH?

Yes. CAIH holders can apply for the CIH comprehensive exam if their current work experience qualifies for broad-scope industrial hygiene practice. They must meet CIH requirements including 48 months of professional-level experience in at least two occupational health stressor categories and the required academic coursework.