Understanding your Noise Survey Report
A noise survey report is produced after a noise survey is conducted in areas where noise exposure is likely to be hazardous. A noise survey involves measuring noise level at selected locations throughout an entire factory or plant, or sections of a work place to identify noise levels in different areas. This is usually done with a sound level meter (SLM).
Are you aware of the legislation around noise in WA?
CHP’s Approved Noise Officers have loads of experience conducting workplace noise surveys in Perth and around WA. We can also help you make sense of your legislative requirements and your noise survey report.
Terms in a noise survey report
Here is glossary of terms that may be a useful reference when first reading your Noise Survey Report. Any other questions, please give us a call.
Noise (dB)
Noise is any audible, unwanted sound – measured in decibels (dB). What is noise to one person may be sound to someone else. There is always a subjective component to the term. Hence, objective assessment with a suitable instrument must be used.
Noise level
refers to the level of sound.
Noise Assessment or Noise Survey
- A measure of the noise levels produced by a single noise source (eg. a particular machine) or predefined area (eg. a workplace).
- A measure of the noise to which an employee is exposed (as can be attained via noise dosimetry)
- An evaluation of the characteristics of noise (eg. an octave band analysis that measures the frequency components of a noise)
- Helps to identify those employees who require audiometric testing
Sound Level Meter (SLM)
An instrument for measuring various noise parameters
A-weighted
A standard weighting of the audible frequency range of 20Hz – 20,000Hz (20kHz) designed to reflect the response of the human ear to noise.
LAeq
Sound levels invariably fluctuate, so the LAeq (A-weighted equivalent continuous sound level) represents the average noise level during the measurement period. It is often referred to as ambient noise, and includes all detectable noise sources, both near and far.
LA90
The A-weighted noise level exceeded for 90% of the measurement period, often referred to as the background noise. While it would normally include the contribution from the specific noise source (i.e. the event site in question), it tends to exclude the effects of short duration noise such as cars passing, dogs barking, sirens, etc., and is generally representative of the basic noise level in a locality.
LA10
The A-weighted noise level exceeded for 10% of the measurement period, and is a measure of the higher noise levels in the ambient noise.
LAMAX
It is the highest A-weighted noise level recorded during the measurement period.
1:3 Octave Band
Frequency analysis of sound such that he frequency spectrum is divided into bands of ⅓ of an octave each.
Tonal
Noise that contains a clearly audible tone that is a distinguishable, discrete, or continuous note (whine, hiss, screech, hum, etc.)
Impulsive
A noise of short duration (typically less than one second), the noise level of which is significantly higher than that of the background noise level.