With the heat of summer and work crews spending more time outdoors comes the sound of machines that were sitting idle a short time ago. Mowers, leaf blowers, chainsaws, jackhammers, and heavy equipment are a few examples of noise sources that could cause an overexposure.
The decibel (abbreviated dB) is the unit of measure for the intensity of sounds. In Occupational Health and Safety, A-weighted decibels (abbreviated dBA) are used to express the intensity of sounds in air as perceived by the human ear. Decibel levels vary and can range from 95 dBA for a lawn mower, 110 for a leaf blower, 125 for a chain saw, and 130 for a jack hammer.
Research has shown that exposure to high noise levels causes hearing loss and may have other harmful health effects. The extent of damage depends primarily on the intensity of the noise and the duration of the exposure.
The Occupational Safety and Health Administration (OSHA) has set exposure limits that are cited in Section 29 of the Code of Federal Regulations, Standard Number 1910.95. The exposure limits are shown in the chart.
| Duration | Sound Level (dB) |
| 8 hours | 90 |
| 4 hours | 95 |
| 2 hours | 100 |
| 1 hour | 105 |
| 1/2 hour | 110 |
| 1/4 hour | 115 |
| impact | 140 |
Additionally, OSHA requires that employees participate in a company-sponsored Hearing Conservation Program whenever a noise exposure equals or exceeds 85 dBA during an 8-hour time-weighted average (TWA).
Environmental Health and Safety has established the Ohio State Hearing Conservation Program to reduce employee noise exposure and eliminate hearing loss in the workplace. The program includes the following elements:
2. Audiometric testing and medical surveillance
3. Hearing protection devices and noise control methods
4. Training
5. Recordkeeping