Noise...In Decibels
Noise-induced hearing loss generally results from repeated exposure to loud noises over time. For workers exposed to excessive noise, hearing loss can occur much sooner. Sound is measured in decibels (dBs) and extended or repeated exposure to sounds at or above 85 decibels can cause hearing loss. According to the National Institute for Occupational Safety and Health (NIOSH), the maximum exposure time (without hearing protection) to noise at a volume of 85 decibels is 8 continuous hours per day. With louder noises, the maximum exposure time decreases. For example, the maximum continuous exposure time to 110 decibels is only 1 minute and 29 seconds per day. These recommendations were calculated from the idea that a 3-decibel increase doubles the amount of noise, which should be counter-balanced by cutting the exposure time in half. So, if 85 decibels without hearing protections has a maximum exposure time of 8 continuous hours, 88 decibels should be limited to 4 hours, 91 decibels should be limits to 2 hours, and so on. For reference, Below is a list of common noises with average decibel levels:
- A jet take-off to a passenger = 130dBs
- Average personal music volume = 106dBs
- An electric power drill = 94dBs
- Normal conversation = 55dBs
- A vacuum cleaner = 70 dBs
- A lawn mower = 90 dBs
- Air compressors (from 3 feet away) = 92 dBs
Noise...Both Physical and Psychological Effects
Aside from the physical effects of hearing loss, exposure to excessive noise can also produce a psychological effect in workers that induces a negative physiological response, such as heightened blood pressure, nausea, and headaches. This is due to the fact that loud and continuous noise alters the way the brain processes speech, makes it difficult to distinguish between words or sounds and disrupts concentration. These changes in standard communication methods reduces comprehension, which often results in anxiety and stress, which can trigger a physiological response. The physical and psychological effects of loud noises can be mitigated by wearing hearing protection.
