Loud noise can create physical and psychological stress, reduce productivity, interfere with communication and concentration, and contribute to workplace accidents and injuries by making it difficult to hear warning signals.

To help identify areas or zones where lower noise levels exist, a comprehensive sound survey of the production area is recommended. It is also valuable to plot the sound level data on an equipment layout or floor plan, then add or draw contour lines of equal sound levels.

Exposure to Noise is measured in units of sound pressure levels called decibels, using an A-weighted sound levels (dBA). There are several ways to control and reduce worker exposure to noise in a workplace where exposure has been shown to be excessive.

Why is job site noise control important to me? Exposure to high levels of noise can cause permanent hearing loss. Neither surgery nor a hearing aid can help correct this type of hearing loss. Construction sites have many noisy operations and can be a significant source of noise exposure. Loud noise can also reduce work productivity

A wide variety of noise sources may exist in the workplace. The NIOSH Sound Level Meter App is a tool to measure sound levels in the workplace and provide noise exposure parameters to help reduce occupational noise-induced hearing loss.

Noise hazards are addressed in OSHA standards for recordkeeping and general industry. This section highlights OSHA standards and documents related to noise. For information on construction employment, see the construction requirements section.

A Standard Threshold Shift, or STS, is defined in the occupational noise exposure standard at 29 CFR 1910.95(g)(10)(i) as a change in hearing threshold, relative to the baseline audiogram for that employee, of an average of 10 decibels (dB) or more at 2000, 3000, and 4000 hertz (Hz) in one or both ears.

By using a sound level "map" and information on employee locations throughout the day, estimates of individual exposure levels can be developed. This measurement method is generally referred to as area noise monitoring.

The most convenient method is the Noise Reduction Rating (NRR) developed by the Environmental Protection Agency (EPA). According to EPA regulation, the NRR must be shown on the hearing protector package.

Cn indicates the total time of exposure at a specified noise level, and Tn indicates the total time of exposure permitted at that level. Exposure to impulsive or impact noise should not exceed 140 dB peak sound pressure level.