The hearing conservation amendment: 25 years later.

It has been twenty-five years since the final version of the Hearing Conservation Amendment was issued by the Occupational Safety and Health Administration in the U.S. Department of Labor. Since that time, some things have changed and others have stayed exactly the same. Certainly the noise-exposed workforce is more knowledgeable about the hazards of noise, and the use of hearing protection devices (HPDs) has greatly increased. There have been significant strides in the technology for measuring noise and for protecting hearing through HPDs. But there is considerable room for improvement. Some of the noise regulation's provisions are embarrassingly outdated, some are in dire need of improvement, and others, such as the requirements for engineering noise control, are not being enforced. Sadly, there seems to be little progress in reducing overall noise exposure levels. What needs to be done at this point is a major overhaul of the noise regulation: recommitment to engineering noise control; reduction of the permissible exposure limit (PEL) to 85 dBA; a shift to the 3-dBA exchange rate; and a nationwide assessment of hearing loss in American workers to determine the effectiveness of current hearing conservation measures to identify and address the weaknesses in programs and regulations.