Manage exposure to noise in the workplace.
Damage to the ear due to noise exposure is cumulative and irreversible, and it is possibly one of the most ignored safety issues in the workplace. There are three things to consider about noise in relation to hearing loss: how loud, how long, and how close?
OSHA’s hearing conservation program requires employers to monitor noise exposure levels in a way that accurately identifies employees exposed to noise at or above 85 decibels (dB) averaged over 8 working hours, or an 8-hour time-weighted average (TWA). Employers must monitor all employees whose noise exposure is equivalent to or greater than a noise exposure received in 8 hours where the noise level is constantly 85 dB. The exposure measurement must include all continuous, intermittent, and impulsive noise within an 80 to 130 dB range and must be taken during a typical work situation.
What does 85 dB sound like? Following are some comparative noise levels found in a public entity workplace:
- 80 decibels: city traffic, manual machine
- 90 decibels: subway train, lawn mower, motorcycle
- 95 decibels: electric drill
- 100 decibels: woodworking shop, factory machinery
- 110 decibels: chainsaw, leaf blower
- 120 decibels: ambulance siren, pneumatic drill
- 130 decibels: jackhammer, power drill, air raid
- 140 decibels: rock concert, firecracker
Hearing loss can be prevented by a combination of increasing the distance between the person and the noise source, decreasing the exposure time to the noise source and using personal protective equipment (PPE). PPE options are earplugs, canal caps and earmuffs. For hearing protection to be effective it must be comfortable and it must be worn consistently for the entire length of the exposure.
While it’s important to protect against hearing loss, it’s also important to not over protect. Select hearing protectors that provide adequate but not excessive protection for overall performance and effectiveness for employees. Workers must be able to hear talking, loudspeaker transmissions, warning signals and important machine sounds, while reducing the risk of permanent hearing damage.