Injuries and Illness

NIOSH Health Hazard Evaluations: What Are They All About?

Usually, you’re well aware of workplace health hazards. But sometimes, conditions may not be obvious or the extent of the hazard known. That’s when a NIOSH health hazard evaluation might be just the thing.

Q. What is a health hazard evaluation?

A health hazard evaluation (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 responds in writing with helpful information or a referral to a more appropriate agency.
  • NIOSH staff calls to discuss the problems and how they might be solved.
  • Identify, find, and describe the change—what, where, when, to what extent?
  • 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?

For private and federal employers:

  • 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.

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.


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Should you request an HHE?

You may wish to request an HHE when there is concern about a health hazard in a workplace. For example, when:

  • 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

How does NIOSH respond to an HHE request?

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 to 6 weeks.

When NIOSH decides that telephone consultation or a workplace visit is needed, a project officer is assigned. Usually, within 4 to 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.


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How are HHE results reported?

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.

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