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Health Hazard Evaluations


HHE Program Information

The National Academies has completed their evaluation of the NIOSH Health Hazard Evaluation (HHE) Program. Based on a scoring system of 1 to 5, with 5 being the highest, the committee rated both the relevance and impact of the HHE Program as 4. The report noted that “If the committee had not been restricted to the use of integers, both scores would have been between 4 and 5.”

The report contains eight overarching recommendations addressing strategic planning, outreach to increase awareness about the program, HHE report recommendations, occupational heath capacity building, information transfer, policy impacts, emerging hazards, and public health emergencies. NIOSH will review the panel’s findings and recommendations, develop an implementation plan, and revise the Program’s strategic plan. These materials will be presented to the NIOSH Board of Scientific Counselors and will be available for public comment.

The National Academies’ report
External Link:

What is a Health Hazard Evaluation?

An HHE is a study of a workplace. It is done to learn whether workers are exposed to hazardous materials or harmful conditions. On the basis of the information you provide, NIOSH responds to an HHE request in one of the following ways:

NIOSH staff writing NIOSH staff responds in writing with helpful information or a
referral to a more appropriate agency.
NIOSH Staff calling NIOSH staff calls to discuss the problems and how they might be
NIOSH Personnel fit-testing a respirator

NIOSH staff visits the workplace. When this happens, they will meet with the employer and the employee representatives to discuss the issues. They will tour the workplace. They may review records about exposure and health, interview or survey employees, measure exposures, and do medical testing. These activities may happen during one or more visits. At the end of this evaluation, NIOSH will provide a written report to the employer and to the employee representatives. This can take from a few months to a few years, depending on the type of evaluation.

Who Can Request an HHE?

Private sector and Federal workplaces

An employee can request an HHE if he or she is currently an employee at the workplace of concern and has the signatures of two other employees. If the workplace has three or fewer employees, the signature of only one employee is enough.

An officer of a labor union that represents employees for collective bargaining can request an HHE.

Any management official may request an HHE on behalf of the employer.

For anyone who submits a request, NIOSH will not reveal to the employer the names of the persons who made the request if they indicate this on the request form

State or local government workplaces

When the workplace is part of a State or local government, NIOSH authority is more limited than for the private and Federal sectors. The cooperation of the employer may be necessary before NIOSH can do an evaluation.

Should you request an HHE?

Workers cutting meat in a slaughterhouse.
Workers cutting meat in a slaughterhouse.
When there is concern about a health hazard in a workplace, you can request an HHE, file a complaint with the Occupational Safety and Health Administration (OSHA), or request help from the OSHA Consultative Service. Some things to consider for each of these options are listed below.

1. When to request an HHE from NIOSH

You are an employee, employee representative, or employer and the following apply:

  • Employees have an illness from an unknown cause.

  • Employees are exposed to an agent or working condition that is not regulated by OSHA.

  • Employees experience adverse health effects from exposure to a regulated or unregulated agent or working condition, even though the permissible exposure limit is not being exceeded.

  • Medical or epidemiological investigations are needed to evaluate the hazard.

  • The incidence of a particular disease or injury is higher than expected in a group of employees.

  • The exposure is to a new or previously unrecognized hazard.

  • The hazard seems to result from the combined effects of several agents.

2. When to request help from the OSHA Consultation Program


You are a small business owner and you want:

  • assistance in recognizing hazards in your workplace.

  • suggestions or options for correcting safety and health issues.

  • assistance in developing or maintaining an effective safety and health program.

  • to reduce workers compensation cost and improve employee morale..

The OSHA On-site Consultation Program:

  • is a free service.

  • is delivered by state (and territorial) governments using well-trained safety and health professionals.

  • is separate from enforcement.

  • is confidential. The company’s name, and any other identifying information provided about the workplace, plus any unsafe or unhealthful working conditions that the consultant uncovers, will not routinely be reported to OSHA enforcement personnel.

  • does not issue and citations, penalties, or fines.

  • will provide you a confidential, written report that summarizes the consultant’s findings.

  • requires the correction of hazards identified by the consultant(s).

  • under specific circumstances, employers with exemplary safety and health programs can be recommend for recognition and provided with an exclusion from general schedule inspections.

3. When to file a complaint with OSHA


You are an employee and the following situations apply*:

  • Immediate enforcement by a regulatory agency is needed.

  • Employees want the employer to comply with existing health and safety standards.

  • The hazard is well recognized.

  • An OSHA standard is known to adequately protect employees from the hazard.

* Employers in the Federal sector may wish to explore the services available through the Division of Federal Occupational Health (DFOH), which maintains an office in each Federal region. State and local government employers may be eligible for help under the OSHA Consultation Program operating in their State. The State or local health department may also be able to help with occupational safety and health issues.

How Does NIOSH Respond to an HHE Request?

Worker torch cutting scrap metal.
Worker torch cutting scrap metal.
NIOSH logs in each request for an HHE and generally sends a letter to the person making the request. Most often this happens within a few weeks.When NIOSH decides to send information or make a referral to another agency, usually a letter is sent within 4–6 weeks.

When NIOSH decides that telephone consultation or a workplace visit is needed, a project officer is assigned. Usually, within 4–6 weeks, the project officer contacts the person who sent in the

request. When the request is made by an employee or union, NIOSH also contacts the employer to let them know about the request and to arrange for a site visit. Typically, NIOSH does not conduct surprise visits.

What protections are provided for employees who request and participate in HHE investigations?

NIOSH staff measuring radiation exposure
NIOSH staff measuring radiation exposure.



If desired and noted on the HHE request form, NIOSH will not reveal to the employer the names of the persons who made the request. Personal information from records, questionnaires, interviews with NIOSH investigators, and individual medical results will be safeguarded in accordance with provisions of the Privacy Act.

Anti-discrimination Provisions

The Occupational Safety and Health Act and the Federal Mine Safety and Health Act forbid employers from retaliating or punishing employees for making HHE requests or cooperating with NIOSH investigators (see Section 11(c) of the Occupational Safety and Health Act or Section 105(c) of the Mine Safety and Health Act). The enforcement of these anti-discrimination provisions is the responsibility of the U.S. Department of Labor. If discrimination is suspected, contact the nearest OSHA or MSHA office immediately.

Procedural Rights of NIOSH and Employee or Employee Representatives

There are 7 legal rights of NIOSH and employees or employee representatives that NIOSH considers non-negotiable:

  • NIOSH and its representatives have the right to enter the workplace to conduct HHE investigations.

  • NIOSH and its representatives have the right to access information and records maintained by the employer that are pertinent to the HHE

  • NIOSH and employees (including management employees) have the right to private and confidential interviews.

  • Worker sweeping floors in a fiberboard manufacturing facility
    Worker sweeping floors in a fiberboard manufacturing facility.
    Employee representatives, including an employee requestor and a representative of any union representing the affected employees, have the right to accompany NIOSH investigators during the initial inspection of any workplace to be evaluated.(NIOSH investigators may have additional employee representatives accompany them if necessary to aid in the investigation.)

  • Employee representatives have the right to participate in an opening and closing conference with NIOSH investigators at the start and conclusion of a NIOSH investigation at the workplace.

  • Employees have the right to wear NIOSH sampling devices and participate in medical tests when offered or requested by NIOSH. (This also applies to management employees.)

  • Employees have the right to read or obtain copies of all HHE interim and final reports. (The employer is required to post the final report in the workplace for 30 days, or supply a list of names and addresses of affected employees so that NIOSH can mail the report directly to them.)

Procedural Rights of the Employer

Regardless of who submitted the request for an HHE, employers have the following rights during HHE investigations:

  • To obtain a copy of the HHE request (excluding the identity of confidential requestors and any accompanying information of a personal nature.)

  • To obtain verbal accounts from NIOSH investigators concerning plans, procedures, and findings at conferences at the beginning and conclusion of NIOSH visits to the workplace.

  • To accompany NIOSH investigators during the initial inspection of the workplace to be investigated.

  • To observe NIOSH investigative procedures during the HHE, except for certain confidential NIOSH-employee interactions, such as private interviews and medical test procedures.

  • To identify, at the start of the investigation, information that is considered trade secret, and to have that information safeguarded by NIOSH unless NIOSH follows procedures outlined in 42 CFR 85.7(b) to remove the trade secret designation from such information. (These procedures provide an opportunity for the employer to defend the trade secret designation.)

  • To require that NIOSH officers comply with all safety and health rules in the workplace, and conduct the investigations in a manner that does not unreasonably disrupt operations.

Role of the Employee Representative

The local, national, or international union may submit an HHE request on behalf of employees it represents. Two employees may authorize a third employee to submit an HHE request on their behalf.

The employee representative has the following rights:

  • To accompany NIOSH investigators on the initial inspection of the workplace.

  • To convey to the NIOSH investigators, privately if requested, additional information related to the HHE request.

  • To participate in the opening and closing conferences.

  • To receive copies of all interim and final reports

How Are HHE Results Reported?

Workers putting in cellulose insulation
Workers putting in cellulose insulation.

NIOSH reports its findings and recommendations to employers, employees, and employee representatives. Verbal reports are normally provided to employer and employee representatives during a closing conference at the conclusion of a site visit, and by telephone. Often, results are only preliminary or incomplete at that time. Written interim reports are sometimes provided while an investigation is still in progress.

When all the information and data have been analyzed, NIOSH issues a report of its final determination, giving findings and recommendations. Copies of this report are sent to the requestor, the employer, employee representatives, OSHA, and other appropriate agencies.

The employer is required to post the final report in a place accessible to employees from all areas evaluated (alternatively, the employer may give NIOSH names and addresses of affected employees to permit NIOSH to mail the report to each affected employee.) Although NIOSH has no authority to force the employer to adopt its recommendations, experience has shown that most employers attempt to address any problems identified in the HHE report.

By What Authority Does NIOSH Conduct HHEs?

In private sector workplaces, NIOSH is supported by the following:

  • The Law
    Section 20(a)(6) of the Occupational Safety and Health Act (Public Law 91-596, 91st Congress, S.2193, December 29, 1970), 29 USC 669 (a)(6), authorizes the Secretary of Health and Human Services (delegated to NIOSH), "following a written request by any employer or authorized representative of employees, to determine whether any substance normally found in the place of employment has potentially toxic effects in such concentrations as used or found." Section 501(a) of the Federal Mine Safety Act of 1977 authorizes NIOSH, "upon the written request of any mine operator or authorized representative of miners, to evaluate potentially hazardous or toxic effects of substances, physical agents, or equipment found or used in mines."

  • Federal Regulations
    The regulations governing NIOSH procedures for conducting HHEs are
    published in Title 42, Code of Federal Regulations, Part 85; Requests for
    Health Hazard Evaluations (42 CFR 85).

In Federal agency workplaces, NIOSH is supported by the following:

  • Law enforcement officers practicing in a firing range
    Law enforcement officers practicing in a firing range.
    The Law
    Section 19 of the Occupational Safety and Health Act (29 USC 668) requires the head of each Federal agency to "establish and maintain an effective and comprehensive occupational safety and health program."

  • Executive Order
    Executive Order 12196 of February 26, 1980, "Occupational Safety and Health Programs for Federal Employees."

  • Federal Regulations
    Title 29, Code of Federal Regulations, Part 1960; Basic Program Elements for Federal Employees Occupational Safety and Health Programs and Related Matters (29 CFR 1960). Section 1960.35 of these regulations describes the procedures for requesting HHEs in Federal agency workplaces.
    NIOSH follows the procedures outlined in the regulations governing HHEs (42 CFR 85) when evaluating Federal agency workplaces.

In other government agency workplaces, NIOSH is supported by the following:

  • The Law
    Section 18 of the Occupational Safety and Health Act (29 USC 667) permits OSHA to approve a plan under which the State assumes responsibility for developing and enforcing occupational safety and health standards. Section 18(c)(6) requires that such a plan, to be approved, must contain satisfactory assurances that the State will "establish and maintain an effective and comprehensive occupational safety and health program applicable to all employees of public agencies of the State and its political subdivisions." Although approved State plans do not ordinarily extend the right to request HHEs to State employees and employers, the State agency charged with carrying out this plan has right-of-access to State and local government workplaces, and could request technical assistance from NIOSH in evaluating the workplaces.

  • Federal Regulations
    In cases where NIOSH responds to requests to evaluate State or local government workplaces, the procedures outlined in 42 CFR 85 are followed.

Occupational Medicine Rotation Program

The NIOSH Health Hazard Evaluation and Technical Assistance Branch provides hands-on, one- and two-month workplace training opportunities to Medical Residents. Residents join staff on a combination of workplace and epidemiologic investigations, public inquiries, health and safety assessments on today's health and safety topics and learn to plan and conduct worksite health evaluations. Residents gain understanding of the role and function of CDC/NIOSH regarding occupational health research and service.

Read more about the Occupational Medicine Rotation Program.


<< Back to HHE Program Home Page

drawing blood for a study, anthrax sampling, abrasive blasting, sanding epoxy resin

Related Publications:

NIOSH Health Hazard Evaluation Program - Short informational brochure

NIOSH Health Hazard Evaluation Program - Informational booklet with request form