CIH exam — how do people handle the breadth of industrial hygiene disciplines in one credential?
I've been working in occupational health and safety for 9 years, primarily in chemical exposure assessment and respiratory protection. I'm targeting the CIH exam next year but I'm intimidated by how broad the exam is — noise, ergonomics, radiation, biological hazards, program management are all domains I've touched but don't work in daily.
My employer will pay for ABIH study materials but I don't know if the official materials are sufficient or if most people supplement heavily. I'm also not sure how to gauge readiness other than practice exams.
What's the honest assessment from people who've passed?
The ABIH study guide is a good starting framework but most people who pass supplement with the Plog Fundamentals of Industrial Hygiene and the ACGIH TLV booklet. The TLV booklet especially — know the exposure limit framework cold.
The CIH practice exam questions here are organized by domain which made it easy for me to drill my weakest areas systematically. Noise and radiation were both lower for me than expected — the practice tests caught that early and I had time to fix it.
Practice exams are the best readiness gauge. Aim to score consistently above 75% on timed practice sets before you book your date. Your score breakdown will tell you exactly which domains need more work.
The breadth is real and you can't specialize your way through it. Every domain is tested. Your chemical and respiratory background will carry you well in those sections but you genuinely need to study noise dosimetry, radiation protection fundamentals, and ergonomic risk assessment methodology.
Quick update on my end — I've been grinding through practice exams for the past few weeks and just hit a 74% on a full-length sim, which honestly felt like a milestone after where I started. The ventilation and toxicology sections are still my weak spots but they're way less scary than they were in March.
I'm sitting for it in October so I've got a few months to shore up the gaps. The breadth thing you're describing is real, it doesn't really go away, but I found that once you stop treating each discipline as its own island and start seeing how they connect the whole thing clicks a little better. Good luck to everyone else in the same boat.