USDOL-OSHA Noise Regulations

Effective Hearing Conservation Programs

Case Study

• General Industry 1910.95

• PEL is an 8 Hour Time Weighted Average of 90

dBA

• Action Level is an 8 Hour Time Weighted Average

of 85 dBA (lower value for extended shifts)

• Construction 1926.52

• PEL is an 8 Hour TWA of 90 dBA

USDOL-OSHA Noise Regulations

Monitoring of employee noise exposure

Institution of feasible engineering and

administrative controls

Personal protective equipment

Employee training

Baseline and annual audiometry (hearing tests)

Prevention of further hearing loss if a “STS” as

been identified

Record Keeping

Sound Mapping

Dosimetry

Octave Band Analysis

◦ Identify High

Noise Areas

◦ Identify Point

Noise Sources

….or use 2-3 foot rule

Dosimeters are used

for personal monitoring

and are valuable when

employees perform a

variety of tasks during

the day and a sound

level survey will not

fully characterize an

employee’s full shift

noise exposure

◦ OBA characterizes the noise in octave bands

◦ Used to identify the characteristic frequency of the sound

◦ Helpful when reviewing noise control strategies

Introduce Feasible Engineering and

Administrative Controls

Reduce It

Modify It

Block It

Reduce It

Modify It

Block It

Consider safety air guns

with noise control features:

DISTANCE

Saw Cutting (6’ Away) 98-101 dBA

Saw Cutting (10’ Away) 91-92 dBA

Saw Cutting (40’ Away) 83-85 dBA

Jack Hammering (6’ Away) 104-106 dBA

Jack Hammering (10’ Away) 96-98 dBA

Jack Hammering (15’ Away) 93-95 dBA

Jack Hammering (50’ Away) 79-81 dBA

How to Calculate Hearing Protection Attenuation Using the NRR:

TWA - (NRR-7) = TWA under the hearing protector

For example:

If the TWA is 98 dB and the NRR is 25 dB

98 - (25-7) = 98 – 18 = 80 dB*

*98 – (25-7)/2 = 98 – 9 = 89 dB

If the TWA is 103 dBA and the NRR is 25 dB

103 - (25-7) = 103 – 18 = 85 dB

Dual protection would be desirable……

Subtract an additional 5 dB

85- 5 = 80 dB*

*103- (25-7)/2 = 103 – 9 = 94

94-5 = 89 dB

Audiometric testing monitors an employee’s hearing over time. Baseline audiogram

Annual audiogram

nnual audiogram will be measured against the baseline audiogram.

To determine if the employee has lost hearing ability or experienced standard threshold shift (STS).

If an employee has experienced a STS, the employer must: Fit or retrofit the employee with adequate hearing

protectors.

Re-train the employee how to use the hearing protectors.

Notify employee within 21 days after the determination that their test show and STS.

CONN-OSHA Consultation Program

860-263-6900

Federal OSHA Area Offices- Compliance Assistance

Specialists

Hartford: 860-240-3152

Bridgeport: 203-579-5581