The Certified Industrial Hygienist (CIH) Exam

An industrial hygienist is an engineer or scientist who works to protect and ensure the health and safety of workers in both the work environment and the community. These professionals strive to anticipate, recognize, evaluate, prevent, and control issues or stressors that can or do occur in a specific work or community area and cause illness among the people who work or live in that environment. These professionals possess post-secondary degrees, ranging from Bachelor’s to Doctorate, as well as several years of direct work experience in the field. The American Board of Industrial Hygiene (ABIH) offers occupational certification for professional industrial hygienists as a means to obtain further credentials and recognition in the profession. One of the requirements to obtaining ABIH certification is to pass the Certified Industrial Hygienist (CIH) examination.

The purpose of the CIH examination is to ensure that industrial hygienists possess the necessary knowledge and skills identified by the ABIH as being important to those who work in this profession. In order to qualify to take the CIH examination, ABIH has set forth criteria with which all applicants must comply. In addition to complying with all Board regulations in effect at the time the individual files an application to take the examination, he/she must

  1. Satisfy all academic requirements including completing Industrial Hygiene (IH) coursework
  2. Meet a work experience requirement
  3. Be working currently as an industrial hygienist.

In order to meet the academic requirement, the applicant must have graduated from an accredited college or university and obtained a Bachelor’s degree in biology, chemistry, physics, chemical engineering, mechanical engineering, or sanitary engineering, or have other acceptable, creditable coursework. Industrial Hygiene coursework requires completion of a minimum of 180 academic hours of specific IH courses in subjects such as toxicology and fundamentals of industrial hygiene.

Eligibility to take the CIH examination also requires the applicant to have completed four years of professional level work experience as an industrial hygienist. Professional level experience means the individual has completed a certain depth of work requirements, had various levels of interactions, acted independently in the workplace, and been accountable for work results. Applicants who have earned an acceptable graduate degree may be able to credit some their education experience toward some of the work experience requirement.

The applicant must also submit at least two professional references: one from his/her current supervisor who can confirm the applicant’s current industrial hygiene work and one from a Certified Industrial Hygienist who can describe the applicant’s work and responsibilities. Only the person who prepares the reference can submit it to ABIH, and must do so on the Board’s Professional Reference Questionnaire form, signing it prior to submission.

The examination, which consists of 180 multiple-choice questions, will test the applicant’s knowledge across broad topics in the overall practice of industrial hygiene. Examples of topics covered on the examination include work environments and industrial processes, biohazards, ergonomics, noise and vibration, and basic science, although questions will not be grouped by topic on the examination. The ABIH website provides a job analysis and definitions reference document to help applicants understand the format of the examination.

The examinations are offered during two timeframes each year: April-May and October-November. The deadline to apply for the spring examination is February 1 each year, and for the fall examination it is August 1. The examination is conducted in two sections, a morning and an afternoon, with each section lasting 2 ½ hours. If examinees wish, they may take a 30-minute break after the first section. All examinees are expected to take a brief tutorial prior to the start of the examination and also complete a short survey upon completion. Applicants must take care to meet all criteria in order for ABIH to schedule them for a specific examination date and location.

Industrial Hygiene Coursework Requirement for the CIH Examination

Industrial Hygiene Coursework Requirement for the CIH ExaminationThe American Board of Industrial Hygiene (ABIH) offers occupational certification for professional industrial hygienists as a means to obtain further credentials and recognition in their profession. One of the requirements to obtaining ABIH certification is to pass the Certified Industrial Hygienist (CIH) examination. The purpose of the CIH examination is to ensure that industrial hygienists possess the necessary knowledge and skills identified by the ABIH as being important for those who work in this profession. In order to qualify to take the CIH examination, the ABIH requires applicants to be in compliance with all Board regulations in effect at the time they file their application. Applicants must also satisfy all academic requirements including completing Industrial Hygiene (IH) coursework, they must meet the work experience requirement, and also be currently employed as an industrial hygienist.

ABIH has specific requirements regarding the Industrial Hygiene coursework the applicant must complete. CIH examination applicants must be able to document that they have completed either 180 academic contact hours or 240 contact hours of continuing education coursework. The completed coursework must be specific courses in industrial hygiene. What is more, at least one-half of the required coursework, that is 90 academic or 120 continuing education contact hours, should involve four broad subject areas: industrial hygiene toxicology, industrial hygiene measurements, and industrial hygiene controls, as well as the fundamentals of industrial hygiene. If the applicant completed any or all of the IH coursework as part of their academic degree, they will be considered to have satisfied this requirement. Below are examples of required IH coursework a CIH examination applicant will need to complete.

The ABIH will accept toxicology coursework that addresses the basics of toxicology. Basic toxicology course content looks at how chemicals adversely affect living systems, specifically human beings. A diverse range of topics will need to be covered, including: absorption, distribution, metabolism, and excretion of toxic substances in the body; dose response relationships; organ systems; biotransformation; and chemical carcinogenesis and mutagenesis, among others.

Courses on the fundamentals of industrial hygiene will teach students how to anticipate, recognize, evaluate, and control various types of hazards that can occur in a given industrial environment or workplace. These steps are the four key processes that must be in place for an industrial hygiene effort to be effective. The hazards to which the four steps apply can be physical, chemical, ergonomic, or biological.

Acceptable courses in the broad subject areas of industrial hygiene measurements and controls are also required. This coursework will cover industrial hygiene measurement techniques used to evaluate occupational exposure to the same four hazards noted above: chemical, physical, biological, and ergonomic. The areas of engineering, substitution, and administration will be included.

The individual may select the remaining hours of coursework from other industrial hygiene subjects that are more narrowly focused. For example, this could include courses in lead, asbestos, mold, blood pathogens, hazardous waste, ventilation standards, noise standards, and confined space standards.

CIH examination applicants are also required to provide documentation that they have completed at least two contact hours of coursework on ethics. The maximum number of contact hours for which the applicant can receive credit toward their IH coursework requirement is five.

If the applicant must take IH coursework beyond that taken previously as part of their academic degree in order to meet the IH coursework requirement, the additional courses can be academic, continuing education, or a combination of both. A semester hour is equal to 15 academic contact hours. One quarter hour is equal to 10 academic contact hours. One continuing education unit is equal to 10 contact hours of continuing education. Supporting documentation, including copies of certificates must be included with the CIH examination application.

Industrial Hygiene Experience Requirement for the CIH Examination

The American Board of Industrial Hygiene (ABIH) offers occupational certification for professional industrial hygienists as a means to obtain further credentials and recognition in their profession. One of the requirements to obtaining ABIH certification is to pass the Certified Industrial Hygienist (CIH) examination. The purpose of the CIH examination is to ensure that industrial hygienists possess the necessary knowledge, experience, and skills identified by the ABIH to work competently and effectively in this profession. In order to qualify to take the CIH examination, the ABIH requires applicants to be in compliance with all Board regulations in effect at the time they file their application. Applicants must meet specific work experience requirements, satisfy academic obligations, and also be currently employed as an industrial hygienist. In order to be eligible to take the CIH examination, the individual must have at least four years of professional level employment experience in the practice of industrial hygiene; this experience must be acceptable to the Board.

ABIH has set specific criteria that are used when determining if work experience meets the condition of “professional level”. First, the experience must have allowed the individual to be able to work and function independently. Did the experience allow the individual to plan work independently? Was the individual afforded the opportunity to self-direct? Could the individual make unilateral decisions and work autonomously?

Another criteria that is used to determine if work experience meets the ABIH’s professional level requirements is that of the depth of work experience the individual possesses. ABIH wants to know that the individual has performed industrial hygiene work that involves recognizing an issue, collecting relevant data, analyzing that data, and correctly interpreting it in order to determine an appropriate and adequate solution for the issue at hand.

ABIH also wants confirmation that the individual has experience interacting with a wide variety of people in the course of carrying out his or her job duties. The expectation is that the industrial hygienist has effectively dealt with people in positions of differing responsibilities, up to and including decision-makers.

The last professional work experience criteria for CIH examination applicants is that, at some point during their minimum four years of employment, they were held accountable for results. That is, ABIH requires that the individual has been responsible for the outcome relating to their work decisions and performance.

If the CIH examination applicant’s work experience is at a pre-professional or technician level, ABIH will not credit it as acceptable for examination eligibility. For the experience to be allowable, ABIH expects it to include what is known as the continuum of the process in the practice of the Industrial Hygiene profession, that is: anticipate, recognize, evaluate, control, and manage occupational health hazards. Work experience that is creditable, however, includes research, teaching, or Industrial Hygiene program administration, as long as that work was performed at a professional level. If the individual performed this work as a student, ABIH will not credit it toward the work experience requirement.

If a CIH examination applicant holds an acceptable bachelor’s degree and moves into a master’s degree or other accredited industrial hygiene program, for purposes of determining the student examination eligibility, ABIH will consider that student to be in “industrial hygiene practice”. The same holds true for industrial hygiene doctoral degree candidates. But, in order to qualify for the work experience equivalency, the individual must have completed their advanced degree.

A CIH examination applicant must also be practicing what ABIH considers to be “broad scope” industrial hygiene. Broad scope means that the individual’s work function includes the continuum of the process of Industrial Hygiene practice, discussed above. Broad scope also includes experience in at least two of four generic categories of occupation health stressors, which include chemical, physical, biological, and ergonomic.

ABIH may credit other education and experience toward the professional level work experience requirement for CIH examination applicants.

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