Acoustic Shock Tests

Acoustic shock disturbance is defined as a permanent disturbance in the auditory system due to a daily noise dose of more than 85 decibels or very loud impact sound and acoustic events known to be above 120 decibels.

It is a long-known fact that very loud sound damages the auditory system. This occurs either with exposure to a single extremely loud sound, typically greater than 120 dB, or with chronic exposure to lower intensity sound. For this reason, most countries have regulations that provide for both an absolute upper limit and a daily or weekly average noise limit to cover occupational noise exposure.

The effects of acoustic shock are pain around the ear, tinnitus, dizziness, hyperacusis, changes in hearing, and a blocked sensation in the affected ear or ears. For some people the symptoms are short lived, but in some people the problem persists and develops other symptoms such as anxiety, depression, insomnia and post-traumatic stress disorder.

Acoustic testing has changed a lot over the years. The standards developed for acoustic testing and acoustic applications were therefore based on filtered data, resulting in the need for continuous analysis using largely true filtered octave and fractional octave analysis. However, the human response to noise and vibration is not very linear in nature, and most mechanical systems have a behavior best characterized by proportional bandwidth analysis.

Noise measurements largely attempt to characterize sound as it is perceived by the human ear. Frequency weighting of the signal is common. The A-Weighting filter applies a frequency weighting that is slow to correlate with the subjective response. Dynamic signal analyzers are acoustic analyzers that can perform acoustic testing that involves evaluating sound power and applying weighting functions.

There are many different forms of airborne acoustic testing, including general level recording, sound pressure spectral measurement, real-time octave sound pressure measurements, sound intensity, sound power and sound quality. These tests mainly focus on real-time octave and third octave, sound intensity, loudness and sound quality.

Our organization also provides acoustic shock testing services with its trained and expert staff and advanced technological equipment, among the numerous test, measurement, analysis and evaluation studies it provides for businesses in various sectors.