The OSHA 30 Guide
Everything you need to know before sitting for OSHA 30-Hour Construction
Why OSHA 30 matters in 2026
OSHA 30-Hour Construction is one of the most recognized credentials issued by OSHA, and 2026 hiring data continues to show OSHA 30 on job postings as either required or strongly preferred for the roles it targets. The certification validates that you can apply real working knowledge, not just recall facts, across 10 distinct exam domains, with the largest weight on Elective Construction Topics. For candidates competing in the OSHA ecosystem, OSHA 30 is a clear signal to a hiring manager that you have invested in measurable, third-party-verified competence.
Who should take OSHA 30
OSHA 30 is most useful for professionals working in or moving toward the OSHA ecosystem. In short: Supervisor-level construction safety certification. If you are early in your career, OSHA 30 is one of the fastest credentials to add to a résumé that recruiters actively screen for. If you are mid-career, it formalizes the skills you already use day-to-day and unlocks roles that gate on it. If you are switching tracks, it gives you a structured curriculum that tells you exactly what to study, in what order, weighted by what the real exam tests.
Exam structure and difficulty
The OSHA 30-Hour Construction exam is organized into 10 domains, each weighted by the official OSHA exam guide. The heaviest weighting is Elective Construction Topics at 30% of the exam, so that is where you should spend the most preparation time. The lightest is Stairways and Ladders at 6%, meaning you can dedicate roughly proportional review time without over-investing.
Format details: Voluntary 30-hour outreach training · No formal exam · Required by many states, GCs, and PLAs for supervisors. Following the domain weights is the single biggest leverage point candidates miss, because many over-study lower-weighted material that feels comfortable.
How to prepare
A practical four-step plan for OSHA 30:
- Read the official OSHA exam guide for OSHA 30 and write down every sub-objective. This becomes your study checklist.
- Use the domain practice quizzes on this page in weight order (heaviest first). Aim for 80% on each domain before moving on.
- When you miss a question, read the explanation for every wrong answer, because that contrastive learning is where understanding compounds.
- Once every domain is at 80%+, take the Mix Quiz repeatedly to simulate real exam conditions across all topics.
Career outcomes and salary
Holders of OSHA 30 in the US currently see compensation in the range of $65k to $120k per year, with median around $88k. Construction supervisor safety credential Salary varies by region, employer size, and complementary skills, but the OSHA 30 credential consistently lifts the floor of what you can negotiate against. Source: BLS (Construction Managers), ZipRecruiter, 2026.
Common pitfalls
The three traps that kill OSHA 30 candidates: (1) over-memorizing acronyms instead of practicing the application of concepts in scenarios, when the exam is scenario-driven, not a vocab quiz. (2) Skipping the heaviest-weighted domain because it feels less interesting, which can fail the whole exam by neglecting Elective Construction Topics. (3) Not timing practice sessions, when the exam has a real clock and pacing is its own skill. Build timing into your last two weeks of prep.
OSHA 30 questions, answered
Is there a final exam for OSHA 30?
OSHA does not mandate one specific proctored exam, since the requirement is completing 30 hours of authorized outreach training. Most authorized providers include quizzes throughout the course and a final knowledge check, commonly with a 70% passing score and a few retry attempts, before issuing your DOL card.
Can you fail OSHA 30?
You can miss the passing score on an individual module quiz with some providers, but you can typically retake it, since the program is built around completing all 30 hours of content rather than screening people out.
Is OSHA 30 online?
Yes, OSHA-authorized outreach trainers offer it fully online or in person; both formats require the full 30 hours of authorized content for the DOL card.
How long does the OSHA 30 card last?
It does not expire under federal rules, though some states, general contractors, and project labor agreements require periodic refreshers, so check your specific job requirements.
How much does OSHA 30 cost?
OSHA does not set a fixed price since independent authorized providers deliver the training; expect roughly $70 to $150 depending on the provider and format, more than OSHA 10 given the extra 20 hours of content.
Who should take OSHA 30 instead of OSHA 10?
OSHA 30 is intended for supervisors, foremen, site safety leads, and anyone with safety responsibility for others. OSHA 10 is the entry-level course for workers. Many states and contractors require the 30-hour card for supervisory roles.
What topics are on the OSHA 30 construction course?
Everything in OSHA 10 (the Focus Four hazards, introduction to OSHA, PPE, and health hazards) plus managing safety and health programs, stairways and ladders, and a wider set of elective topics such as excavations, scaffolds, cranes, and confined spaces.
Is this OSHA 30 practice test free?
Yes. All OSHA 30 practice questions on QuizBuffet are free, organized by course topic, with explanations for every answer and no signup.