Why are scores dropping? I think my own experience sheds some light on the subject.
In the early 1980s, after getting my "five years of professional experience" that helped qualify me to sit for the CIH exams, I applied to the American Board of Industrial Hygiene (ABIH). The application required a reference from a CIH who was familiar with my work. I didn’t know any CIHs then and our community did not have a local chapter of the American Industrial Hygiene Association (AIHA). I worked with a Certified Safety Professional, but he couldn’t be substituted for a CIH.
Back then, I thought the process of becoming a CIH to be overly strict and the ABIH and CIHs I soon met to be arrogant.
I eventually qualified to sit for the Core examination. (Successful completion of two exams is required to become a CIH. The Core exam covers the basic knowledge and skills related to the functions of industrial hygiene. The second, or Comprehensive, exam covers more advanced knowledge.) Since I didn’t know many industrial hygienists back then, I studied alone and I didn’t study a lot. I had sample questions to review, and I went over them many times. I was confident that I would pass the exam with ease. Wrong.
My overall score was ranked by the ABIH as "very deficient." How could this be? I thought I knew a lot about industrial hygiene. After all, my job title was industrial hygienist, and I worked for a chemical manufacturing corporation. I collected lots of chemical samples, measured noise, conducted training, and so on. How could I fail an exam that simply tested basic knowledge of industrial hygiene? Did I truly know so little about my profession?
Failing the Core exam so miserably turned out to be a blessing. At first I blamed the exam system. I even made up excuses: The people who already had a CIH didn’t want more competition, so they made the exam real hard to pass. I also slammed the exam as more of a "trivial pursuit" than a real test of significant industrial hygiene issues.
It turned out that there was nothing wrong with the exam system, but there was something wrong with me. I underestimated the peer support and CIH mentor relationships needed to more fully understand industrial hygiene issues. Needing to understand more about industrial hygiene, I located all the industrial hygienists I could find in my community. We formed a new local section of the AIHA and I served as its first president. I also found a CIH mentor, Stephen K. Hall, Ph.D., who guided my learning about industrial hygiene. A group of us studied for the CIH exams together and all of us eventually passed.
Many people taking the CIH exams are like me when I first failed. I didn’t attend any local AIHA meetings, I knew few industrial hygienists, and I didn’t have a CIH mentor. This is a typical pattern for many people today who are rather new to the profession. They have the book smarts and know some science of industrial hygiene, but they also need to learn the "art" of the profession. This can best be learned from peer support and a CIH mentor. My bet is that if more people learn more about the art of industrial hygiene, then the CIH exam pass rates will rise back to historical averages.
There are other issues involved with the fall-off that should be looked at: Are CIH exams harder now than they were in the past?
According to the ABIH, the CIH exams are no more difficult now than they were in the past. The ABIH feels it can make this claim because each exam question is weighted and evaluated by an independent testing service. Also, since the testing uses a standardized scoring method the ABIH feels the passing score for exams has not significantly changed over time. Supposedly these and other exam control processes keeps every batch of exams on a level playing field from year-to-year.