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Sound Monitoring

California employers must conduct sound monitoring when noise levels are suspected to exceed action levels that can lead to hearing loss or other issues. Qualified professionals perform dosimetry to measure employee noise exposures over full work shifts. Results are compared to Permissible Exposure Limits (PELs) in OSHA’s noise standard.

CDMS has extensive expertise conducting sound monitoring following recognized dBA measurement protocols. We thoroughly survey your facility to identify areas of concern. Our experienced technicians use calibrated Type II dosimeters and sound level meters to sample equipment noise, process operations, and workplace ambience. CDMS delivers detailed technical reports with noise mapping and recommendations.

Let us handle this critical function to determine if noise hazards exist so appropriate controls can be implemented.

Regulatory bodies
  • Occupational Safety & Health Association (OSHA)
  • California Occupational Safety & Health Association (Cal/OSHA)
  • The National Institute for Occupational Safety and Health (NIOSH)
Who needs it

Any facility where there is a potential that sound levels are exceeding action levels are required to do testing.

Regulation reference
  • 29 CFR 1910.95
  • 8 CCR 5095-5100
  • 29 CFR 1926.52
What our service provides:

CDMS will conduct preliminary noise monitoring to determine if noise levels at the Client’s facility exceed Occupational Safety & Health Association (OSHA) Permissible Noise Exposure Levels. This phase of monitoring will be used to determine whether the Client’s facility has noise levels that require more extensive testing or corrective actions.

CDMS will be conducting the monitoring in the work environment during a typical work day when usual noise levels are known to be present. The sampling areas will be identified by the Client’s staff and the CDMS Project Manager.

Upon completion of the monitoring a report will be prepared that outlines the following:

  • Tabulated results of the monitoring in each area.
  • Mapping of the noise levels in the affected areas
  • Actions required if the noise levels are above the Occupational Safety & Health Association (OSHA) limits

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Contact us

When is sound monitoring required?
If noise levels are suspected to exceed action levels or regulatory limits.

What equipment is used to measure sound?
Dosimeters, sound level meters, octave band analyzers.

What are action levels for noise exposure?
85 dBA as an 8-hour TWA, 50% of Permissible Exposure Limits (PELs).

What are the Occupational Safety & Health Association (OSHA) Permissible Exposure Limits (PELs)?
90 dBA for 8 hours, 95 dBA for 4 hours, etc.

What data is collected during sound surveys?
Noise sources, levels, variations, employee exposures, octave band analysis.

Where should dosimeters be placed on workers?
Shirt collar to represent noise entering the ears.

How long are monitoring sessions?
Long enough to calculate 8-hour time-weighted average (TWA) exposures.

What factors can affect instrument accuracy?
Wind screens, calibration, interference.

When should monitoring be repeated or continued?
Annually, whenever processes change, or results approach action levels.

What information is included in sound survey reports?
Methods, maps, results, interpretations, recommendations.

What training is required for personnel conducting monitoring?
Proper use of instruments, procedures, and interpretation of results. For more information please visit our Hearing Conservation Training section.

What are common sound monitoring mistakes?
Improper microphone placement, lack of calibration, bad instrument choice.

Who should review and interpret the results?
A qualified professional like an industrial hygienist. Contact Us to get support or request Sound Monitoring. Our skilled team of EH&S specialists is ready to assist you.

What hearing protection may be needed?
Selection depends on noise levels and exposures.

Do employees need training on sound monitoring results?
Yes, they must be informed of the results.

Which regulatory agency enforces noise monitoring?
Federal Occupational Safety & Health Association (OSHA) and state plan agencies like Occupational Safety & Health Association (Cal/OSHA).

How can sound monitoring findings improve hearing conservation?
Identify needs for controls, protection, and hearing testing.

How long must sound monitoring records be kept?
At least 2-3 years is advisable. 30+ years recommended.

What are the National Institute for Occupational Safety and Health (NIOSH) noise measurement methods?
The National Institute for Occupational Safety and Health (NIOSH) Manual of Analytical Methods, Ch. 6.

How can equipment noise output be determined?
By taking measurements at the operator’s position per ANSI standards.