Study guide
1.1 OHST Exam Logistics, Blueprint & Scoring
Occupational Hygiene and Safety Technician OHST
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1 Chapter 1: Exam Overview & Prep Strategy
1.1 OHST Exam Logistics, Blueprint & Scoring 1.2 Study Strategy & Test-Taking Tactics
2 Chapter 2: Hazard Identification, Risk Assessment & Incident Investigation
2.1 Job Safety Analysis (JSA) & Hazard Recognition 2.2 Risk Assessment Frameworks & Risk Matrix Calculations 2.3 Workplace Inspections & Safety Audits 2.4 Incident Investigation & Root Cause Analysis (RCA) 2.5 Human Factors & Ergonomic Hazard Analysis
3 Chapter 3: Hazard Control & Safety Engineering
3.1 Hierarchy of Controls & Safety Engineering Principles 3.2 Machine Guarding & Mechanical Hazards (OSHA 1910 Subpart O) 3.3 Electrical Safety & Lockout/Tagout (LOTO - OSHA 1910.147) 3.4 Fall Protection & Working at Heights (OSHA 1910 Subpart D / 1926 Subpart M) 3.5 Confined Space Entry & Permitting (OSHA 1910.146) 3.6 Personal Protective Equipment (PPE) Selection & Maintenance (OSHA 1910 Subpart I)
4 Chapter 4: Safety, Health & Environmental Programs
4.1 Safety Management Systems (ANSI/ASSP Z10, ISO 45001, OSHA VPP) 4.2 OSHA Recordkeeping & Injury Reporting (OSHA 300, 300A, 301) 4.3 Regulatory Compliance & OSHA Inspections / Citations 4.4 Hazard Communication & GHS SDS Management (OSHA 1910.1200) 4.5 Environmental Compliance & Waste Management (RCRA, CERCLA, CAA, CWA) 4.6 Contractor Safety & Management Systems
5 Chapter 5: Health Hazards & Industrial Hygiene
5.1 Chemical Hazards, Exposure Limits (PEL, TLV, REL) & Toxicology 5.2 Airborne Sampling, Air Monitoring & Direct-Reading Instruments 5.3 Physical Hazards: Noise, Hearing Conservation & Radiation 5.4 Thermal Stress, Ventilation Systems & Indoor Air Quality 5.5 Biological Hazards, Bloodborne Pathogens & Infection Control
6 Chapter 6: Organizational Communication, Training & Business
6.1 Adult Learning Principles & Safety Training Development 6.2 Training Delivery, Evaluation & Documentation 6.3 Safety Culture, Organizational Change & Worker Engagement 6.4 Safety Management Communication & Reporting Techniques 6.5 Safety Program ROI, Cost-Benefit Analysis & Financial Justification
7 Chapter 7: Safety Math, Emergency Preparedness & Fire Protection
7.1 Safety Mathematics, Units & Unit Conversion Calculations 7.2 Incident Rate Calculations & Applied Statistics 7.3 Emergency Action Plans (EAP) & Incident Command System (ICS) 7.4 Fire Prevention, Fire Protection Systems & Workplace Security
8 Chapter 8: Ethics & BCSP Professional Standards
8.1 BCSP Code of Ethics & Professional Conduct 8.2 Ethical Decision-Making & Conflict of Interest Scenarios 8.3 Professional Responsibilities & Continuing Recertification
1.1 OHST Exam Logistics, Blueprint & Scoring
Key Takeaways Explain This Topic AI
The OHST exam is a 4-hour, 200-question computer-based test administered by BCSP through Pearson VUE.
BCSP uses criterion-referenced scoring (modified Angoff); treat every item as scored because pretest items are not identified.
Eligibility requires 3 years of experience with at least 35% of duties requiring occupational hygiene or safety technical skills.
Fees are $140 application + $300 exam ($440 if purchased separately; BCSP App+Exam combo is $426).
Recertification requires 20 points over 5 years, including at least 0.5 ethics points.
Last updated: July 2026
OHST Exam Logistics, Blueprint & Scoring
Quick Answer: The OHST exam is a 4-hour, 200-question computer-based test from the Board of Certified Safety Professionals (BCSP), delivered at Pearson VUE. Eligibility requires three years of experience with at least 35% of duties in occupational hygiene or safety. Study to the official OHST6 seven-domain blueprint.
The Occupational Hygiene and Safety Technician (OHST) certification is awarded by the Board of Certified Safety Professionals (BCSP) . It recognizes technicians and practitioners who apply industrial hygiene and occupational safety skills as a primary or secondary part of their job. Understanding current logistics and the official blueprint is the first step in preparation.
Governance and Administration
BCSP sets eligibility, develops the examination blueprint from job-task analyses, and maintains the credential. The examination is delivered worldwide through Pearson VUE testing centers in a secure computer-based format. Official results are available immediately after the exam is submitted.
Exam Format and Timing
Total Questions: 200 multiple-choice questions.
Time Limit: 4 hours (240 minutes).
Pacing: About 1.2 minutes per question (72 seconds). Time management matters.
BCSP and major prep sources describe a mix of scored items and unscored pretest (beta) items embedded in the form. You will not be told which items are pretest items, so treat every question as scored. Because there is no penalty for guessing, never leave a blank.
Scoring and Passing Standard
The OHST uses criterion-referenced scoring. Subject-matter experts set the cut score using methods such as the modified Angoff method (and related standard-setting approaches), so the required performance is tied to competence rather than a curve against other candidates.
BCSP does not publish a single fixed public raw-score cut (for example, "exactly 109 of 175") on its credential pages. Many third-party prep resources cite a working target near about 66% of scored items . Use that only as a study benchmark; your official pass/fail decision is the BCSP scaled result for your form. Your score report also shows domain-level performance to guide remediation if you must retake.
Cost and Financial Investment
Current BCSP Credentials At-A-Glance fees for OHST:
- Fee Amount
- Application fee $140
- Examination fee $300
- App + Exam combo $426
- Exam bundle option $550 (exam bundle); App+Exam bundle combo $676
- Annual renewal $145
- Eligibility extension $100
If you purchase the application and exam separately, the cash outlay is $440 . The App+Exam combo ( $426 ) is the lower path when bought together. Failed attempts require another exam fee and a mandatory wait before retesting.
Eligibility Requirements
Experience: Minimum of three (3) years where at least 35% of job duties require technical skills and knowledge in occupational hygiene or safety .
Education: No minimum education requirement for OHST.
Disclosure: Applicants must disclose relevant criminal convictions or actions against professional licenses/credentials; BCSP reviews these confidentially and may deny based on that policy.
Eligibility window: After approval, candidates generally have one year to sit for a purchased examination authorization.
Retake Policies and Recertification
Retake wait: At least six (6) weeks between exam attempts.
Recertification cycle: Five (5) years .
Points: 20 recertification points per cycle (OHST), including ethics activity as required in the current Recertification Guide (commonly cited as at least 0.5 ethics points ).
Annual renewal fee: Required to keep the credential active ( $145 on the current At-A-Glance schedule).
The Exam Blueprint (OHST6 — Official Domain Weights)
Use the current BCSP OHST6 Examination Blueprint (V.2021.05.04) . Allocate study time to these weights:
Domain Weight Focus
1. Fundamental Math and Science and Business Calculations/Analysis 11.3% Math, chemistry/physics basics, statistics, performance metrics, loss economics
2. Safety, Health, and Environmental Programs (Includes Risk Management) 19.5% Programs, audits, investigations, risk management, GHS, waste, continuous improvement
3. Hazard Identification and Control 21.1% Recognition and control of workplace hazards, hierarchy of controls, PPE, energy, heights, equipment
4. Health Hazards and Basic Industrial Hygiene 15.8% Exposures, sampling, noise, biological hazards, ergonomics, respiratory hazards
5. Emergency Preparedness, Fire Prevention, and Security 11.5% EAPs, drills, ICS, emergency equipment, fire/security preparedness
6. Organizational Communication and Training/Education 12.6% Adult learning, training design/delivery/evaluation, communication, conflict resolution
7. Ethics and Professional Conduct 8.2% BCSP Code of Ethics, confidentiality, unbiased safety information
Domain 3 (Hazard Identification and Control) is the largest single domain at 21.1% , followed by Domain 2 at 19.5% . Older third-party outlines that still list Hazard Identification near 31% (or invent alternate seven-domain mixes) are not current—use OHST6.
BCSP Certifications Comparison
Certification Target Audience Experience Required Degree Required Focus Area
OHST Safety/Hygiene Technicians 3 Years (≥35% hygiene/safety duties) None General Safety & Hygiene Implementation
CHST Construction Safety Techs 3 Years (≥35% SH&E duties in construction) None Construction Safety
ASP Associate Safety Professionals 1 Year (≥50% preventative professional SH&E) Bachelor's (or qualifying associate) Broad SH&E fundamentals (path toward CSP)
CSP Certified Safety Professionals 4 Years (≥50% preventative professional SH&E) + approved credential Bachelor's Advanced SH&E practice
The OHST is ideal for practitioners executing hygiene and safety work on the ground—sampling, inspections, controls, and training that keep workers safe day to day.