Noise Hazards

Typically, sound becomes hazardous to the inner ear when the intensity and duration of the exposure exceed a particular criterion level. In industry, the levels of 85 to 90 dBA are considered hazardous to workers exposed to noise for an 8-hour work. However, high level sounds (>100 dBA) are especially hazardous even for brief periods of time (< 15 minutes). Agricultural workers may find themselves at an increased risk for noise-induced hearing loss (NIHL) during the long hours of equipment operation at certain times of the year due to seasonal demands on work schedules (2,3).

Farmers operate a variety of equipment capable of producing hazardous sound levels. Table 35.1 is compiled from research studies and investigations and lists most of the common noise sources and levels (in dBA) reported in the farm environment (4-7). Farmers rank ordered the loudest noise sources on the farm as follows: tractors, grain dryers, combines, chainsaws, grain grinding, and animals. One agricultural noise source rarely catalogued but frequently associated with farming is firearm noise. The majority (84% to 90%) of farmers do report having firearm noise exposures. These peak sound pressure levels (SPL) can range from 143 dB to 173 dB depending on the gauge or

Table 35.1. Typical noise sources and sound levels in farming.

Noise source

Noise levels (dBA)

Tractor Grain dryer Combine Chainsaw Grain grinding Pig squeals One-row beet puller Orchard sprayer Pneumatic conveyor Riding mower Garden tractor Shotguns and rifles Crop dusting aircraft

74-112 81-102 80-105 77-120 93-97 85-115 94

79-89

85-106 100

88-94

143-173 (Peak) 83-116

Sources: Data from Lankford, Zurales et al. (6), Dobie (5), and Lankford et al. (7).

caliber fired. These findings indicate that in addition to the typical farm noises, firearm noise is a component of most farmers' noise exposure profile. In addition, farmers (58%) commonly reported high levels of noise exposures outside the farm. These additional exposures include noise from non-agricultural employment settings as well as hobbies or entertainment (4-9).

0 0

Post a comment