In addition to the resources available from OSHA to address workplace health concerns, assistance also is available from the Health Hazard Evaluation (HHE) program of the National Institute for Occupational Safety and Health (NIOSH). Through the HHE program, NIOSH responds to requests for evaluations of workplace health hazards from employers, employees and their representatives, and government agencies. At no cost to the employer or employees, NIOSH conducts studies of workplaces in response to these requests to learn if workers are exposed to hazardous materials or harmful conditions. Workplace exposures studied include chemicals, biological agents, work stress, noise, radiation, and ergonomics. NIOSH evaluates the workplace environment and the health of employees by reviewing records and conducting on-site nvironmental and medical testing. Upon completion of the study, NIOSH issues a report that includes recommendations for addressing identified problems, reducing exposure, and preventing disease. HHEs can be especially helpful in the following situations:

• 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.