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OCCUPATIONAL HEARING LOSS (OHL) SURVEILLANCE

LOGO: Occupational Hearing Loss Surveillance

Facts and Definitions

Scope of the Problem

In the United States, hearing loss is the third-most common chronic health condition among older adults after hypertension and arthritis.
Over 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.

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.