📋 Jump to Rubric
- Exam Overview
- 1. Air Sampling
- 2. Analytical Chemistry
- 3. Basic Science
- 4. Biohazards
- 5. Biostatistics
- 6. Community Exposure
- 7. Engineering Controls
- 8. Ergonomics
- 9. Health Risk Analysis
- 10. IH Program Management
- 11. Ionizing Radiation
- 12. Noise
- 13. Non-Engineering Controls
- 14. Non-Ionizing Radiation
- 15. Thermal Stressors
- 16. Toxicology
- FAQs
The CIH exam tests your knowledge across 16 distinct rubrics—each covering a different aspect of industrial hygiene practice. Understanding what's tested in each rubric, how heavily it's weighted, and what key concepts to master is essential for effective preparation.
This guide breaks down every rubric with specific study targets, key concepts, and practice strategies. Use it alongside your practice questions to ensure complete coverage of the exam content.
Total Questions
180 Questions
Time Limit
5 Hours
Content Areas
16 Rubrics
Passing Standard
Scaled Score
Exam Overview & Weight Distribution
Not all rubrics are weighted equally. Understanding the distribution helps you allocate study time effectively—though remember that all rubrics appear on the exam and neglecting any topic is risky.
Toxicology
~12%
Air Sampling & Instrumentation
~11%
Engineering Controls & Ventilation
~10%
IH Program Management
~9%
Noise
~7%
Biohazards
~6%
Other Rubrics (10 remaining)
3-5% each
📈 Smart Study Strategy
1
Diagnose
Take practice tests to identify your weak rubrics
2
Prioritize
Focus on high-weight AND weak areas first
3
Practice
Complete 30-50 questions per rubric minimum
4
Review incorrect answers thoroughly
Review
⚠️ Common Mistake
Many candidates focus only on high-weight rubrics and ignore lower-weight ones. This is dangerous. A rubric weighted at 4% still represents ~7 questions—enough to determine pass/fail if you get them all wrong. Cover ALL 16 rubrics in your preparation.
Rubric 1: Air Sampling & Instrumentation
1
Air Sampling & Instrumentation
Critical
~11% of exam
This high-weight rubric covers the methods and equipment used to collect air samples for evaluating workplace exposures. You must understand sampling strategies, equipment selection, calibration, and quality assurance.
📚 Key Topics to Master
- Sampling pump calibration and flow rate verification
- Active vs. passive sampling methods
- Filter selection (MCE, PVC, PTFE, glass fiber)
- Sorbent tubes and their applications
- Direct-reading instruments (PIDs, FIDs, electrochemical sensors)
- Impingers and bubblers for gas/vapor collection
- Respirable, thoracic, and inhalable sampling conventions
- Sampling strategy development (SEGs, worst-case, random)
- Quality assurance: blanks, duplicates, spikes
- NIOSH and OSHA sampling methods
🧮 Calculation Topics MATH
- Sample volume calculations (flow rate × time)
- Concentration calculations from analytical results
- Sampling train efficiency
- Detection limits and quantitation limits
💡 Study Tips
Know the specific applications for each sampling media type. Understand when to use personal vs. area sampling. Be comfortable with pump calibration procedures and troubleshooting common problems (e.g., flow rate drift, breakthrough).
Rubric 2: Analytical Chemistry
2
Analytical Chemistry
Medium
~4% of exam
This rubric covers laboratory analytical methods used to analyze IH samples. You need to understand the principles, applications, and limitations of major analytical techniques.
📚 Key Topics to Master
- Gas chromatography (GC) and GC-MS principles
- High-performance liquid chromatography (HPLC)
- Atomic absorption spectroscopy (AAS)
- Inductively coupled plasma (ICP) methods
- X-ray diffraction (XRD) and X-ray fluorescence (XRF)
- Gravimetric analysis for particulates
- Phase contrast microscopy (PCM) for asbestos
- Transmission electron microscopy (TEM)
- Quality control in analytical laboratories
- Method detection limits and reporting
💡 Study Tips
Focus on matching analytical methods to sample types (e.g., metals → ICP-MS, organics → GC-MS, asbestos → PCM/TEM). Understand the difference between screening and confirmatory methods.
Rubric 3: Basic Science
3
Basic Science
Medium
~4% of exam
This rubric tests foundational scientific knowledge—chemistry, physics, and biology—that underlies industrial hygiene practice.
📚 Key Topics to Master
- Gas laws (ideal gas law, partial pressures)
- Unit conversions (ppm to mg/m³, temperature scales)
- Vapor pressure and volatility
- Chemical properties affecting exposure (solubility, reactivity)
- Particle physics (aerodynamic diameter, settling velocity)
- Basic anatomy and physiology (respiratory system, skin)
- Physics of sound, light, and heat transfer
🧮 Calculation Topics MATH
- ppm ↔ mg/m³ conversions
- Ideal gas law applications
- Vapor pressure calculations
💡 Study Tips
The ppm to mg/m³ conversion (mg/m³ = ppm × MW / 24.45) is heavily tested. Know it cold. Understand how vapor pressure relates to evaporation rate and exposure potential.
Rubric 4: Biohazards
4
Biohazards
High
~6% of exam
This rubric covers biological agents that pose health risks in occupational settings, including bacteria, viruses, fungi, and other biological hazards.
📚 Key Topics to Master
- Bloodborne pathogens (OSHA requirements, hepatitis, HIV)
- Airborne infectious diseases (TB, COVID-19, influenza)
- Mold and fungi (sampling, remediation, health effects)
- Legionella and cooling tower management
- Biosafety levels (BSL-1 through BSL-4)
- Indoor air quality and bioaerosols
- Zoonotic diseases
- Sampling methods for biological agents
- Disinfection and sterilization methods
- PPE for biological hazards
💡 Study Tips
Know the OSHA Bloodborne Pathogens standard requirements thoroughly. Understand the different biosafety levels and what activities/organisms belong in each. Mold assessment and remediation protocols are frequently tested.
Rubric 5: Biostatistics & Epidemiology
5
Biostatistics & Epidemiology
Medium
~5% of exam
This rubric covers statistical methods for analyzing exposure data and epidemiological concepts for understanding disease patterns in working populations.
📚 Key Topics to Master
- Descriptive statistics (mean, median, mode, standard deviation)
- Lognormal distribution of exposure data
- Geometric mean and geometric standard deviation
- Confidence intervals and their interpretation
- Exposure distributions and exceedance fractions
- Epidemiological study designs (cohort, case-control, cross-sectional)
- Relative risk, odds ratio, attributable risk
- Bias, confounding, and effect modification
- Statistical decision making for compliance
🧮 Calculation Topics MATH
- Arithmetic and geometric mean calculations
- Standard deviation calculations
- Confidence interval calculations
- Coefficient of variation
- Relative risk and odds ratio
💡 Study Tips
Understand WHY exposure data is typically lognormal and when to use geometric vs. arithmetic mean. Practice statistical calculations until they become automatic. Know how to interpret confidence intervals for compliance decisions.
Test Your Knowledge So Far
Practice questions covering all rubrics—identify your weak areas before the exam
Rubric 6: Community Exposure
6
Community Exposure
Standard
~3% of exam
This rubric addresses exposures that affect communities beyond the workplace, including environmental releases and public health concerns.
📚 Key Topics to Master
- Environmental regulations (Clean Air Act, Clean Water Act)
- Air dispersion modeling basics
- Environmental exposure assessment
- Risk communication with communities
- Emergency response and release reporting
- Indoor air quality in non-industrial settings
- Environmental justice considerations
💡 Study Tips
This lower-weight rubric often overlaps with IH Program Management (emergency response) and other rubrics. Focus on understanding environmental regulations at a high level and the principles of community risk communication.
Rubric 7: Engineering Controls & Ventilation
7
Engineering Controls & Ventilation
Critical
~10% of exam
This is one of the most heavily weighted and calculation-intensive rubrics. It covers ventilation system design, evaluation, and other engineering approaches to controlling workplace hazards.
📚 Key Topics to Master
- General dilution ventilation principles
- Local exhaust ventilation (LEV) systems
- Hood types (enclosing, capturing, receiving)
- Capture velocity requirements
- Duct design and transport velocity
- Fan selection and fan laws
- Static pressure, velocity pressure, total pressure
- System effects and losses
- Air cleaning devices (filters, scrubbers, collectors)
- HVAC system evaluation
- Substitution, isolation, process modification
🧮 Calculation Topics MATH HEAVY
- Q = VA (flow rate, velocity, area)
- Capture velocity equations
- Fan laws (flow, pressure, power relationships)
- Dilution ventilation calculations
- Hood static pressure calculations
- Velocity pressure to velocity conversion
💡 Study Tips
This rubric is CALCULATION HEAVY. Master Q=VA and the fan laws (remember: 1-2-3 for flow-pressure-power exponents). Practice hood/duct calculations until they're automatic. Understand when to use dilution vs. local exhaust ventilation.
Rubric 8: Ergonomics
8
Ergonomics
Medium
~5% of exam
This rubric covers the identification and control of musculoskeletal hazards in the workplace, including risk factor assessment and ergonomic interventions.
📚 Key Topics to Master
- Musculoskeletal disorders (MSDs) and risk factors
- NIOSH Lifting Equation and applications
- Repetitive motion injuries
- Workstation design principles
- Hand tool design and selection
- Vibration exposure (hand-arm and whole-body)
- Ergonomic assessment methods (RULA, REBA, Strain Index)
- Administrative controls for ergonomic hazards
- Office ergonomics
🧮 Calculation Topics MATH
- NIOSH Lifting Equation (RWL and LI)
- Vibration exposure calculations
💡 Study Tips
The NIOSH Lifting Equation is testable—understand each multiplier and how changes affect the recommended weight limit. Know the major ergonomic risk factors: force, repetition, posture, vibration, contact stress.
Rubric 9: Health Risk Analysis & Hazard Communication
9
Health Risk Analysis & HazCom
Medium
~5% of exam
This rubric covers hazard identification, risk assessment methodologies, and communication of chemical hazards to workers.
📚 Key Topics to Master
- OSHA Hazard Communication Standard (GHS)
- Safety Data Sheets (SDS) - 16 sections
- GHS labeling requirements and pictograms
- Risk assessment frameworks
- Exposure-response relationships
- Occupational exposure limits (OELs) - PELs, TLVs, RELs
- Uncertainty factors in risk assessment
- Qualitative vs. quantitative risk assessment
- Risk communication principles
💡 Study Tips
Know all 16 sections of an SDS and what information appears in each. Understand the GHS pictograms and their meanings. Be clear on the differences between OSHA PELs, ACGIH TLVs, and NIOSH RELs.
Rubric 10: IH Program Management
10
IH Program Management
High
~9% of exam
This heavily weighted rubric covers the management aspects of industrial hygiene programs, including regulatory compliance, program development, and professional conduct.
📚 Key Topics to Master
- OSHA regulatory framework and standards
- IH program development and implementation
- Exposure assessment strategies
- Similar exposure groups (SEGs)
- Record keeping requirements
- Medical surveillance programs
- Emergency response planning
- Training program development
- Ethics and professional conduct
- Cost-benefit analysis for controls
- Management systems (ISO 45001)
💡 Study Tips
This rubric tests practical IH knowledge. Know OSHA record keeping requirements (300 log, 300A). Understand how to define and use SEGs. Be familiar with common OSHA standards and their key requirements.
Rubric 11: Ionizing Radiation
11
Ionizing Radiation
Medium
~4% of exam
This rubric covers radiation types, measurement, biological effects, and protection principles for ionizing radiation hazards.
📚 Key Topics to Master
- Types of ionizing radiation (alpha, beta, gamma, X-ray, neutron)
- Radiation units (rem, sievert, rad, gray, curie, becquerel)
- Biological effects of radiation exposure
- ALARA principle
- Time, distance, shielding controls
- Inverse square law
- Half-life and decay calculations
- Dosimetry and monitoring
- Regulatory limits (NRC, OSHA)
- Contamination control
🧮 Calculation Topics MATH
- Inverse square law (I₁d₁² = I₂d₂²)
- Half-life and decay calculations
- Unit conversions
💡 Study Tips
Master the inverse square law—it appears frequently. Know the characteristics of each radiation type (penetrating ability, shielding requirements). Understand the difference between exposure, absorbed dose, and dose equivalent.
Rubric 12: Noise
12
Noise
High
~7% of exam
This heavily tested rubric covers noise measurement, hearing conservation programs, and noise control strategies.
📚 Key Topics to Master
- Sound physics (frequency, wavelength, decibels)
- Hearing mechanism and noise-induced hearing loss
- Sound level meters and dosimeters
- OSHA noise standard requirements
- Hearing conservation programs
- Audiometric testing and interpretation
- Standard threshold shift (STS)
- Hearing protection devices and NRR
- Engineering controls for noise
- OSHA vs. NIOSH criteria differences
🧮 Calculation Topics MATH HEAVY
- Decibel addition (logarithmic)
- OSHA noise dose calculations
- TWA from dose
- Effective NRR calculations (derated)
- Permitted exposure times
💡 Study Tips
NOISE IS CALCULATION HEAVY. Master dB addition (remember: equal sources add 3 dB). Know the OSHA permitted exposure times cold. Understand the difference between OSHA 5 dB and NIOSH 3 dB exchange rates.
Rubric 13: Non-Engineering Controls
13
Non-Engineering Controls
Medium
~5% of exam
This rubric covers administrative controls and personal protective equipment (PPE) as methods for protecting workers.
📚 Key Topics to Master
- Hierarchy of controls
- Respiratory protection program requirements
- Respirator selection (APF, types, limitations)
- Fit testing requirements and methods
- Protective clothing selection
- Chemical protective gloves (breakthrough time, permeation)
- Administrative controls (job rotation, work practices)
- Training requirements for PPE
- Medical evaluation for respirator use
💡 Study Tips
Know the OSHA Respiratory Protection standard requirements thoroughly. Understand assigned protection factors (APFs) for different respirator types. Be familiar with glove selection based on chemical compatibility.
Rubric 14: Non-Ionizing Radiation
14
Non-Ionizing Radiation
Standard
~4% of exam
This rubric covers electromagnetic radiation that doesn't have enough energy to ionize atoms, including UV, visible, IR, microwave, and RF radiation.
📚 Key Topics to Master
- Electromagnetic spectrum
- Ultraviolet radiation (UV-A, UV-B, UV-C)
- Laser classification and hazards
- Infrared radiation
- Microwave and radiofrequency radiation
- Extremely low frequency (ELF) fields
- Measurement techniques
- Biological effects and health hazards
- Exposure limits (ACGIH TLVs)
- Control measures and PPE
💡 Study Tips
Know the electromagnetic spectrum and where each type of non-ionizing radiation falls. Understand laser classifications (1-4) and their hazards. UV exposure from welding is commonly tested.
Rubric 15: Thermal Stressors
15
Thermal Stressors
Medium
~4% of exam
This rubric covers heat and cold stress hazards, assessment methods, and control strategies.
📚 Key Topics to Master
- Heat stress physiology (thermoregulation)
- Heat-related illnesses (heat stroke, exhaustion, cramps)
- WBGT measurement and calculation
- Metabolic heat and workload categories
- Work-rest regimens
- Heat stress controls
- Cold stress hazards (hypothermia, frostbite)
- Wind chill calculations
- Acclimatization
🧮 Calculation Topics MATH
- WBGT indoor (0.7 NWB + 0.3 GT)
- WBGT outdoor (0.7 NWB + 0.2 GT + 0.1 DB)
- Time-weighted average WBGT
💡 Study Tips
Know both WBGT formulas (indoor vs. outdoor) cold—this is frequently tested. Understand why natural wet bulb has the highest weighting (humidity is the biggest factor in heat stress). Know the signs and treatment of heat-related illnesses.
Rubric 16: Toxicology
16
Toxicology
Critical
~12% of exam
This is the HIGHEST WEIGHTED rubric on the exam. It covers the study of adverse effects of chemical substances on living organisms—foundational knowledge for all industrial hygienists.
📚 Key Topics to Master
- Dose-response relationships
- Routes of exposure (inhalation, dermal, ingestion)
- Absorption, distribution, metabolism, excretion (ADME)
- Acute vs. chronic toxicity
- Target organ toxicity
- Carcinogenesis and carcinogen classification
- Reproductive and developmental toxicity
- Sensitization and allergic responses
- Toxicological endpoints (LD50, LC50, NOAEL, LOAEL)
- Specific toxicants (metals, solvents, asbestos, silica)
- Biomarkers of exposure and effect
- Chemical interactions (additive, synergistic, antagonistic)
💡 Study Tips
This is your MOST IMPORTANT rubric—invest significant study time here. Know the health effects of common industrial toxicants (lead, asbestos, silica, benzene, hexavalent chromium). Understand dose-response curves and what LD50/LC50 mean. Master the concepts of NOAEL and LOAEL.
✅ You've Reviewed All 16 Rubrics
Now it's time to test your knowledge. Take practice tests to identify which rubrics need more attention. Remember: understanding these topics conceptually is important, but you also need to practice applying this knowledge through exam-style questions.
Frequently Asked Questions
What topics are on the CIH exam?
The CIH exam covers 16 rubrics: Air Sampling & Instrumentation, Analytical Chemistry, Basic Science, Biohazards, Biostatistics & Epidemiology, Community Exposure, Engineering Controls & Ventilation, Ergonomics, Health Risk Analysis & Hazard Communication, IH Program Management, Ionizing Radiation, Noise, Non-Engineering Controls, Non-Ionizing Radiation, Thermal Stressors, and Toxicology. Each rubric has specific weight on the exam, ranging from approximately 3% to 12%.
Which CIH exam topics are most important?
The highest-weighted rubrics are Toxicology (~12%), Air Sampling & Instrumentation (~11%), Engineering Controls & Ventilation (~10%), and IH Program Management (~9%). However, all 16 rubrics appear on the exam, and neglecting any topic is risky. Many candidates fail by over-focusing on familiar areas while ignoring weaker rubrics. A balanced approach covering all topics is essential.
How should I study for the CIH exam?
Effective CIH study involves: (1) Taking a diagnostic test to identify weak rubrics, (2) Systematically reviewing all 16 rubrics with emphasis on weak areas, (3) Completing 500-1,000+ practice questions with thorough review of incorrect answers, (4) Mastering calculations for ventilation, noise, statistics, and heat stress, (5) Taking full-length practice exams under timed conditions. Plan for 4-6 months of preparation with 10-15 hours per week.
Are there many calculation questions on the CIH exam?
Yes, calculations are a significant part of the exam. The most calculation-heavy rubrics are Engineering Controls & Ventilation, Noise, Biostatistics, Thermal Stressors, Basic Science, and Ionizing Radiation. You'll use an on-screen calculator and the BGC equation sheet is provided. Practice calculations extensively—they're where many candidates lose points.
How many questions should I practice for each rubric?
As a minimum, aim for 30-50 practice questions per rubric—more for high-weight rubrics like Toxicology and Ventilation, and for rubrics where you're weak. Total, you should complete 500-1,000+ practice questions before the exam. Quality matters as much as quantity: thoroughly review every incorrect answer.
Ready to Start Practicing?
You now have a comprehensive overview of every CIH exam rubric. The next step is putting this knowledge into practice. Our question bank covers all 16 rubrics with detailed explanations for every answer—helping you identify weak areas and build the exam-ready knowledge you need to pass.
Practice All 16 Rubrics
1,000+ exam-style questions with detailed explanations covering every topic