Noise Surveys Done Right.

According to OSHA regulation 29 CFR 1910.95(d)(3), noise monitoring must be repeated whenever changes in production, processes, equipment, or controls could increase employee noise exposure or reduce the effectiveness of existing hearing protection.

Although OSHA does not specify a fixed interval for repeat monitoring, the National Institute for Occupational Safety and Health (NIOSH) recommends repeat monitoring at least every two years when employee noise exposures equal or exceed an 8-hour TWA of 85 dBA.

As a practical best practice, many companies perform updated noise surveys:

• Following major equipment or process changes

• When expanding operations or production lines

• After employee noise complaints

• Every 2–3 years for ongoing hearing conservation program management

OSHA’s Occupational Noise Standard (29 CFR 1910.95) establishes two primary exposure thresholds; Action Level and Permissible Exposure Limit:

Action Level (AL)

85 dBA as an 8-hour Time-Weighted Average (TWA)

Employees exposed at or above the Action Level must be included in a Hearing Conservation Program.

Permissible Exposure Limit (PEL)

90 dBA as an 8-hour Time-Weighted Average (TWA)

Where employee exposures exceed the PEL, employers must implement feasible engineering and/or administrative controls to reduce exposure levels. Hearing protection is also required until controls are shown to be effective.

Exposure to impulsive or impact noise should not exceed 140 dB peak sound pressure level.

Noise-induced hearing loss is influenced by both noise intensity and exposure duration. Because of this, OSHA requires more conservative exposure criteria for extended work shifts.

For shifts longer than 8 hours, the OSHA Action Level must be adjusted downward. Examples include:

• 8-hour shift: 85 dBA

• 10-hour shift: 83.4 dBA

• 12-hour shift: 82.1 dBA

Noise Survey Solutions evaluates employee exposures with respect to applicable shift length to ensure accurate OSHA compliance interpretation.

There are two primary instruments used during a workplace noise survey:

Personal Noise Dosimeters

Wireless personal dosimeters are worn by employees throughout the workday to measure cumulative noise exposure and calculate an 8-hour Time-Weighted Average (TWA).

Personal noise dosimetry is the most accurate method for evaluating employee exposure across changing tasks and work areas.

Noise Survey Solutions utilizes Casella dBadge2 wireless personal noise dosimeters for all surveys.

Sound Level Meters

A sound level meter is used to collect targeted measurements from specific machines, tools, processes, and work areas.

These measurements help identify high-noise sources and support engineering control and noise mapping efforts.

Noise Survey Solutions utilizes a Casella CEL-620 Type 1 integrating sound level meter with octave-band analysis capability.

Noise dosimetry measures an employee’s cumulative noise exposure over the course of a work shift and is used to determine OSHA compliance with exposure limits.

Targeted sound level measurements, on the other hand, evaluate noise from specific machines, tasks, or areas within a facility.

Both methods provide important information:

• Dosimetry determines employee exposure risk

• Sound level measurements identify hazardous noise sources and support noise control efforts

A comprehensive noise survey typically includes both.

All of our reports are designed to serve as both compliance documentation and a practical decision-making tool.

All of our reports include:

• (10) Personal noise dosimeters

• Color-coded exposure charts for easy interpretation

• Targeted sound level measurements

• OSHA compliance analysis

• Hearing protector assessment

• Site-specific recommendations and best practices

• Calibration documentation

Optional services include:

• Noise Mapping

• Additional Noise Dosimeters

• Hearing Conservation Program development

Our reports are designed to clearly explain findings and help organizations make informed hearing conservation decisions.

No. In most cases, employees continue performing their normal job duties throughout the monitoring process.

Personal noise dosimeters are lightweight, wireless instruments designed to measure real-world employee exposure during routine operations.

Because the goal of a noise survey is to evaluate actual workplace conditions, monitoring is typically conducted during normal production activities.

Noise monitoring is commonly performed in industries where employees may be exposed to hazardous sound levels, including:

• Manufacturing

• Food and beverage processing

• Metal fabrication and machining

• Plastics and injection molding

• Utilities and energy

• Warehousing and distribution

• Construction materials and aggregates

• Transportation and heavy equipment operations

Any workplace with significant machinery, compressed air systems, impact tools, or sustained production noise may require evaluation under OSHA’s hearing conservation standard.

Yes. Noise Survey Solutions can develop visual noise maps that plot measured sound levels throughout a facility.

Noise mapping can help:

• Identify high-noise areas

• Support engineering control evaluation

• Improve employee communication and signage

• Assist with hearing protection policies and program management

Noise mapping is available as an optional service.

No. Noise Survey Solutions does NOT provide residential noise testing, neighborhood noise complaint investigations, or local noise ordinance/compliance monitoring.

Our services are strictly focused on occupational noise exposure assessment, employee safety, and OSHA hearing conservation compliance.