OCCUPATIONAL HEARING LOSS (OHL) SURVEILLANCE
Facts and Definitions
Scope of the Problem
- In the United States, hearing loss is the third-most common chronic physical condition among adults after hypertension and arthritis.
- About 11% of the U.S. working population has hearing difficulty.
- About 24% of the hearing difficulty among U.S. workers is caused by occupational exposures.
- About 8% of the U.S. working population has tinnitus (‘ringing in the ears’) and 4% has both hearing difficulty and tinnitus.
What causes Occupational Hearing Loss (OHL)?
- OHL can occur when workers are exposed to loud noise or ototoxic chemicals.
- Noise is considered loud (hazardous) when it reaches 85 decibels or higher, or if a person has to raise his/her voice to speak with someone 3 feet away (arm’s length).
- Ototoxic chemicals (and examples) include:
- organic solvents (styrene, trichloroethylene, mixtures)
- heavy metals (mercury, lead, trimethyltin)
- asphyxiants (carbon monoxide, hyrdrogen cyanide)
How Many Workers are Exposed?
- About 22 million workers are exposed to hazardous noise each year.
- About 10 million workers are exposed to solvents and an unknown number are exposed to other ototoxicants.
What is OHL Surveillance?
OHL surveillance includes:
- Collecting worker hearing data, exposure data and related information for analysis;
- Estimating how many workers have hearing loss or related health outcomes and how many workers are exposed;
- Examining these estimates by industry and occupation; and
- Monitoring trends over time.
The NIOSH OHL Surveillance Project commenced to establish a national repository for OHL data, and to conduct surveillance and research of this common occupational illness.
- Page last reviewed: July 5, 2017
- Page last updated: July 5, 2017
- Content source:
- National Institute for Occupational Safety and Health Division of Surveillance, Hazard Evaluations, and Field Studies