Hearing damage from loud noise can happen anywhere, as the human ear is incredibly sensitive. The ears cannot distinguish between a lawnmower at 90dB or a concert at 90dB. Gradual hearing loss can be caused by any prolonged sound above 85db. This loss relates to both the intensity of the sound and the length of exposure.
Normal conversation noise measures 60dB, and the sound measurement from a chainsaw or car horn at 110dB.
Any noise exposure above 140dB will cause pain to your ears and instant damage. The most common cause of sound induced hearing (NHL) loss, is in the workplace. NHL is permanent but more important is preventable.
Most modern noise dosimeters contain internal dataloggers, which are useful in terms of capturing the complete time history for the exposure period. Software is then able to manipulate the data into a presentable format. The dosimeter should be field checked with the calibrator before use and also field checked after the sound monitoring has finished to ensure the validity of the measurement.
Care must be taken into positioning of the microphone of the noise dosimeter and must be placed as close as possible to the ear without obstructing any other safety equipment worn by the worker, or be obstructed by lapels, jackets, harnesses etc, and also placed so that sound reflections from head do not affect the dosimeter measurements.
Dosimeters such as Cirrus Research plc's doseBadge is the ideal instrument for personal workplace noise exposure sampling. The doseBadge is the original wireless personal noise dosimeter and is the ideal instrument for personal noise exposure measurements.