Exam FAQs

 Click on the questions to view the answers below.

  1. What is the purpose of the exam?
  2. How is the passing score determined?
  3. How are the exams scored?
  4. There have been changes to the names and number of subject areas over the last couple of years on my performance reports (included with exam results letters), as well as changes in their descriptions. Why?
  5. When I average my scores in the subject areas, it doesn't equal my exam score. Why is that?
  6. How is it determined how many questions from each performance domain will appear on each exam?
  7. What are the pass rates on the exams?
  8. Do ABIH examinations still contain questions that pertain to US-specific laws?
  9. Are there sources of documentation, other than the Candidate Handbook (such as newsletters, etc.), prepared by the ABIH that give exam-specific information?
  10. Does the ABIH endorse or work with any of the organizations providing exam-prep materials to assist them in developing their products? What about organizations that offer 1-week intensive review courses? Do they work with the ABIH to tailor their courses to the exam?
  11. What are the procedures for taking the exam?
  12. I use a TI-83+ graphing calculator. Is it allowed during the exam?
  13. If I do not pass the examination, how long must I wait before I can take it again?
  14. To reapply for the examination, what materials must be included in the request to take the exam again?
  15. Explain the IH Coursework requirement. During what period must the courses be taken under the new “IH coursework” qualifications?

QUESTION 1: What is the purpose of the exam?

ANSWER: The purpose of the exam is to help ensure that professionals working in this field have the skills and knowledge that have been identified as being important in the practice of industrial hygiene.

Successful completion of the exam - after meeting the educational requirements and meeting the comprehensive, professional-level industrial hygiene experience requirements - is the means by which the Board attempts to identify those practitioners that have demonstrated these skills in the comprehensive practice of industrial hygiene.

This is not an easy process. As mentioned above, the examination is part of the overall process, and it is the intent of the Board that the exam be fair, reasonable, current, and also representative of a broad range of industrial hygiene topics.

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QUESTION 2: How is the passing score determined?

ANSWER: The method used by the ABIH for setting the passing score is the Item Response Theory (IRT). Scored questions for the exam are chosen from among those available that have adequate IRT and performance statistics. Scored questions are chosen to meet the exam blueprint. Exam items are pre-tested before being used as scored items by including a number of experimental items on the exam that are not included in the scoring of the test.

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QUESTION 3: How are the exams scored?

ANSWER: The passing score is a total number of questions answered correctly. There is no penalty for incorrect answers (such as “number correct minus a percentage of the number of incorrect answers”).

All questions have the same point value. A “passing” score is not required in each of the individual subject areas (rubrics). It will be to the candidate’s advantage to attempt to answer all questions.

Each examinee is informed of his or her pass/fail status immediately after completing the examination. These are preliminary results, pending verification by the examination consultants and ABIH. Examinees will receive their official results in writing approximately four weeks after taking the exam.

An examinee who fails an examination will be informed of his or her overall score.

All examinees receive a performance report indicating scores in the individual subject areas.

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QUESTION 4: There have been changes to the names and number of subject areas over the last couple of years on my performance reports (included with exam results letters), as well as changes in their descriptions. Why?

ANSWER: There have been some minor changes in the subject area names and definitions. These are intended to reflect the ongoing changes in the field. They also are in response to comments from the industrial hygiene community in general.

For example, the rubric that was previously reported as "Air Pollution" has been changed to "Community Exposure" to allow for the addition of questions in related areas of community health to that rubric. The old rubric of "Personal Protective Equipment" has been renamed "Non-engineering Controls" to reflect the inclusion of questions in such areas as administrative controls.

Other changes from year to year in subject area reporting are related to minor changes in the numbers of questions in given areas on that particular exam. Our testing and educational consultant does not recommend reporting subject area scores for any area with less than a certain number of questions on the exam, so subject areas are sometimes combined. For that reason, “Ionizing and Non-ionizing Radiation” (for example) might sometimes appear separately but be combined as "Radiation" at other times if the number of questions in those areas change.

The construction of the examinations, in terms of the number of questions from each subject area, changes very little from one exam to the next, but a small change is sometimes enough to change the appearance of the performance report.

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QUESTION 5: When I average my scores in the subject areas, it doesn't equal my exam score. Why is that?

ANSWER: As is stated in the Individual Test Performance Report that is included with the results letter, the number of questions from each subject area is not equal. Therefore, the numerical average of the subject area scores, which are percentage scores, does not equal the overall score.

Each question is worth the same value, no matter what subject area it belongs to or how many questions there are from that subject area on the exam. A score of 7 correct answers in a subject area with 10 questions (reported in the performance report as 70%) will not balance out a score of 60% in a subject area with 25 questions (15 correct answers). The percentage correct for these two subject areas combined would be 62.9%, not 65%.

It should also be noted that passing the examination is NOT contingent upon getting a minimum score in each subject area or in any specific subject. What matters is the total number of questions answered correctly.

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QUESTION 6: How is it determined how many questions from each performance domain will appear on each exam?

ANSWER: The performance domains are major areas of responsibility that define the role of a CIH practitioner. These domains were identified by subject matter experts during a Job Analysis (JA).

During the JA validation study, a sample of Diplomates are asked to evaluate the performance domains, rating each on importance, criticality, and frequency. Based on the survey data, test specifications are developed that identify the proportion of questions from each domain that will appear on the certification examination.

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QUESTION 7: What are the pass rates on the exams?

ANSWER: The statistics on candidate performance are posted on our exam pass rate page.

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QUESTION 8: Do ABIH examinations still contain questions that pertain to U.S.-specific laws?

ANSWER: ABIH no longer banks items such as OSHA or EPA related questions that are regulatory specific to one country.

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QUESTION 9: Are there sources of documentation, other than the Candidate Handbook (such as newsletters, etc.), prepared by the ABIH that give exam-specific information?

ANSWER: Not from the Board. There are study guides and other sources of information out there, but the Board doesn’t evaluate them. We don’t know how helpful, complete, or accurate any of them are.

Sometimes AIHA Local Sections have study guides that they have compiled themselves and sometimes they are involved in forming study groups. It’s worthwhile checking the ACGIH and AIHA publications catalogs for helpful references, too.

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QUESTION 10: Does the ABIH endorse or work with any of the organizations providing exam-prep materials to assist them in developing their products? What about organizations that offer 1-week intensive review courses? Do they work with the ABIH to tailor their courses to the exam?

ANSWER: No, the Board doesn't have a working relationship with any of those organizations. The Board does not review, evaluate, or track their performance, or maintain a list of what's available. We are unable to recommend any of them specifically or comment on which ones are better or worse than any of the others.

Checking with colleagues who have taken and passed the examinations may provide an insight as to how others prepared for the examinations and what preparation materials they used.

If any of the organizations request information, we refer them to what is available to candidates and the general public, such as the "Candidate Handbook," the equation sheet, or the updated JA.

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QUESTION 11: What are the procedures for taking the exam?

ANSWER: Generally, examinations are offered electronically at Prometric testing locations during two windows (April-May and October-November) each year. You can schedule an exam anytime within those windows (depending on the hours of your chosen test center - some are open Sundays, some aren't).

The application deadlines are February 1 for the spring exam window and August 1 for the fall exam window. View our Prometric Scheduling page for details on scheduling an examination.

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QUESTION 12: I use a TI-83+ graphing calculator. Is it allowed during the exam?

ANSWER: No. Because of the variety of calculators available and the difficulty in verifying that nothing is stored in memory, the Board has decided to allow only non-programmable calculators.

There are a number of calculators readily available in the $10 range that will do logs, natural logs, exponents, and e raised to an exponent. Whatever calculator you plan to use should be obtained well ahead of time so you can become familiar with it before exam time.

Examinees must provide a non-programmable calculator selected from the approved list below. They may bring spare calculator batteries or a backup calculator (from the approved list).

  • Casio - Models FX-115, FX-250, FX-260, FX-300, FX-350, and FX-991
  • Hewlett-Packard - Models hp-9S, hp-10S, hp-30S, and hp-300S Note: hp-9G is not acceptable
  • Texas Instruments - Models TI-30, TI-34, TI-35, and TI-36

Any calculator within the series listed is acceptable. Not all models within a series are listed because of the variety and the model changes that take place. For example, the listing of a Texas Instruments TI-30 as "approved" means that such models as the TI-30X, TI-30Xa, TI-30XII, and TI-30XIIs are all acceptable.

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QUESTION 13: If I do not pass the examination, how long must I wait before I can take it again?

ANSWER: You cannot retake an examination within 3 months of sitting for that examination. For example, if you take the examination in the spring and are notified that you did not pass, you can apply for the Fall exam prior to the August 1 deadline.

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QUESTION 14: To reapply for the examination, what materials must be included in the request to take the exam again?

ANSWER: When you are approved to sit for the exam, you do not have to submit anything other than a letter and $75 reapplication fee every time you want to retake/reschedule within 2 years.

After 2 years, we need a reapplication form, Professional Reference Questionnaire (PRQ), and $75 reapplication fee.

For example, if someone applied for the Fall 2010 exam, took it, and did not pass, all he or she would need for approval to retake it in the Fall 2011 would be a letter and $75 reapplication fee. If they were not successful by the Spring 2012 exam, he or she would have to submit the reapplication form, PRQ (from their current supervisor or principal client) and a reapplication fee for Fall 2012.

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QUESTION 15: Explain the IH Coursework requirement. During what period must the courses be taken under the new "IH coursework" qualifications?

ANSWER: The Board requires applicants to document completion of 180 academic contact hours or 240 continuing education contact hours of specific industrial hygiene courses. At least half of the required coursework (90 academic or 120 continuing education contact hours) must cover the broad subjects of industrial hygiene toxicology, fundamentals of industrial hygiene, measurements and controls.

Acceptable toxicology courses will cover the essential aspects of toxicology (adverse effects of chemicals on living systems) with an emphasis on humans. Topics covered are likely to include dose response relationships; absorption, distribution, metabolism and excretion of toxic substances in the body; biotransformation; organ systems; and chemical carcinogenesis and mutagenesis.

Fundamentals courses are likely to address recognizing hazards/stressors found in the work environment. These include chemical, physical (noise, radiation, thermal), biological, and ergonomic stressors.

Measurement courses and control (engineering, substitution, administrative, PPE) courses will address the same four broad stressor categories as fundamentals (chemical, physical, biological, and ergonomic).

To meet the 90/120 contact hours required in the broad IH subject areas, you may, for example, meet the requirement for fundamentals by taking a course titled “Fundamentals of IH” or a series of courses that, when added together, substantially equal a fundamentals course. In some combination, you are expected to show coursework in all four broad IH subject areas: toxicology, fundamentals, measurements and controls.

The remaining coursework may be in industrial hygiene subjects that are narrower in scope (such as asbestos, lead, mold, and confined space entry). Regulatory refresher courses can be counted only once.

The IH Coursework requirement will be satisfied if the necessary contact hours were completed as part of the applicant’s academic degree.

If additional coursework is taken to meet this requirement, then academic courses, continuing education courses, or a combination can be submitted. In general, one semester hour equals 20 continuing education contact hours (15 academic contact hours) and one quarter hour equals 13 continuing education contact hours (10 academic contact hours). One CEU equals 10 continuing education contact hour.

For documentation, copies of certificates need to be sent with the application.

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This page was last updated on October 18, 2013