The Modern Evolution of Hearing Conservation Regulations

By Theresa Y. Schulz, PhD 

It is interesting to study the noise standards that have been promulgated in the US 

over the last decade or so. These regulations are likely to have long-lasting impact. 

The Occupational Safety and Health Administration (OSHA) Hearing Conservation 

Amendment (March 1983) continues to have influence not only in the workplace but 

in the debate over new regulations. Both the Mine Safety and Health Administration 

(MSHA) and Federal Railroad Administration (FRA) regulatory preamble documents 

state the desire to be consistent with OSHA. An examination of Table 1, which 

compares the major components of the three regulations and the 1998 NIOSH “best 

practices” criteria, depicts the extent to which that intent is met. 

There has been some regulatory activity in the last decade which may give some 

hope for evolution and updating based on the wealth of science that has occurred 

during the last quarter of a century since the OSHA regulation was enacted. However 

there has also been some “back-sliding” toward more lenient standards. The MSHA 

noise standard made regulatory progress in September 2000 by emphasizing 

engineering and administrative controls, followed by personal protective equipment, 

in the hierarchy of noise intervention. MSHA’s requirement for technician certification 

(today only available from CAOHC) strengthened the training requirements for 

audiometric testing in hearing conservation programs and MSHA also added the 

requirement of dual hearing protection at 105 dB TWA. 

There were many subtle differences between OSHA and MSHA based on comments 

and a desire to clarify some of the vague aspects of the OSHA noise standard, and 

meet the needs of the regulated mining industry. One example pertains to the ceiling 

for exposures. OSHA says, “no exposures >115 dBA,” which is interpreted to mean 

no unprotected exposures above that level, giving credit for the assumed 

effectiveness of hearing conservation programs, hearing protection devices and 

administrative and engineering controls. MSHA specified that a “P” code1

 violation be 

issued for any protected or unprotected exposures >115 dBA. 

The Federal Railroad Administration (FRA) noise standard for railroad operating 

employees, which went The Modern Evolution of Hearing Conservation 

Regulationsinto effect February 26, 2007, was expressly based on the OSHA 

standard but also uses MSHA for comparison. The preamble states that the FRA 

defers to OSHA as the “primary regulator of noise in the workplace,” but also 

acknowledges the need for some departure from the OSHA regulation (FRA Preamble 

II.B). As an example, FRA requires testing at 8000 Hz “because it will allow 

employers to identify hearing loss sooner.” The FRA rejected MSHA’s hierarchy of 

noise controls in favor of requiring specific engineering interventions and focusing on 

appropriate hearing protection which would still allow communication and audibility, 

and identification of excessive noise through employee-filed “excessive noise 

reports.”2

 Where OSHA has no specific mandate requiring employees to take 

advantage of the employer-paid audiogram, it has been traditionally a condition of 

employment and is generally accepted that OSHA-covered workers require an annual 

audiogram. MSHA addressed this issue in its preamble; however, they made no 

significant change. MSHA employers are required to offer annual audiograms but 

MSHA stopped short of requiring employees to comply with annual audiometric 

testing. The MSHA preamble does allow that mine operators can also make 

audiometric monitoring a condition of employment. FRA requires employees to 
complete audiometric testing and hearing conservation training only every three 

years, but requires that training be offered at least once a year. 

The FRA loosened some OSHA requirements as well: 

• Audiometric retest can occur within 90 days of the periodic test vs. OSHA’s 30 

day requirement; 

• Employees must be notified within 30 days about changes in their hearing vs. 

OSHA’s 21 days; 

• Exposures up to 120 dB(A) are allowed for up to 5 seconds, citing the safety 

issue of needing horn blasts to warn the public of oncoming trains. 

The FRA states that audiologists or physicians are responsible for the audiometric 

testing in a hearing conservation programs and qualifies that the physician must 

have “experience and expertise in hearing and hearing loss.” 

There appears to be a general reluctance to deviate too far from the OSHA regulation 

however. As an example, FRA wrote to OSHA asking of any plans to move from a 5-

dB to a 3-dB exchange rate. OSHA replied that there were no such plans and FRA 

has stayed with 5 dB despite recommendations from experts in the field to the 

contrary. 

Discussion

One would hope that employers would want to use “best practices” rather than being 

minimally compliant but the realities of the workplace reveal the unfortunate focus 

on minimal compliance. The preamble documents for these regulations are rich with 

information. One would also hope that with the evolution of hearing conservation 

regulations each would “build” on its predecessors. In some aspects that has 

occurred but in others, the new regulations “tear down” the gains made by previous 

regulations. Table 1 is set up with the regulations in chronological order and the 

NIOSH Criteria Document to the right. See if you think there is “progress” or 

“regress” as you move from left to right. 

Theresa Y. Schulz, PhD is a Team Leader at the NIOSH Pittsburgh Research 

Laboratory, Hearing Loss Prevention Branch, the President of the National Hearing 

Conservation Association (NHCA) and a former Chair of CAOHC. She can be 

contacted at TSchulz@cdc.gov.

1 A “P” Code is an administrative device to document (in an MSHA database) when overexposure 

conditions remain despite the implementation of all feasible engineering and administrative controls to 

reduce the miner’s noise exposure to or below the Permissible Exposure Limit (PEL). The term “P” Code 

derives from the requirement to wear protective equipment (e.g. HPDs). 

2 The term ‘‘Excessive Noise Report,’’ refers to a report filed by a locomotive cab occupant that indicates 

that the locomotive is producing an unusual level of noise such that the noise significantly interferes with 

normal cab communications or that the noise raises a concern with respect to hearing conservation. The 

employee is required to report such excessive noise and the training requirements include how and when 

to make an excessive noise report. The railroad is required to respond to each report.
Table 1: Comparison of Noise Exposure Regulations