CHAPTER TEN
Standards on Occupational Noise Exposure
Measurements and Hearing Protectors
Alberto Behar, P. Eng., CIH and Lee Hager

Standards try to help manage the world we live in and the things we do in a manner that is repeatable and manageable. The standards process ensures that when we buy a pound of coffee, it’s really a pound, and that a quart of milk is really a quart. People sometimes ask, what are standards? Why do we need them? Who writes them, and who’s responsible for publishing them and keeping them up to date?

Wikipedia, the free encyclopedia (http://www.wikipedia.org) states that a technical standard is, “...an established norm or requirement.” It’s usually a formal written document that establishes uniform engineering or technical criteria, methods, processes and practices.

Standards are “best practices” that describe how to consistently do important things in a way that is understood and repeatable—things like electrical standards, for example, describe how houses are to be wired (so the electrician knows which wire is which) and what is meant by “117V AC” (so the microwave manufacturer puts the right parts inside their appliance).

Standards essentially provide specifications and descriptions about “how to.” Most often they deal with how to measure, or how to build or, finally, how to manage. In this chapter, the standards of interest describe how to measure workplace noise exposure, how to estimate the effect of noise exposure on one’s hearing, and how to determine the effectiveness of hearing protectors.

Some standards go beyond measuring, and describe how to apply information. The hearing protector evaluation standards described here provide such an example. Some standards also provide direct guidance to end users, for example, on how to select appropriate hearing protection devices for certain kinds of noise levels, or how to use and care for these devices.

It’s important to recognize that standards development is an ongoing process. The people who develop standards are constantly working to improve and update these documents to reflect new scientific findings, new technologies, or improved practices in their areas of interest. The standards discussed in this chapter may undergo revision at any time, and the reader is encouraged to investigate the most recent revision for the latest information.

Experts in a given field determine that there is a need to establish a “norm” or standard practice. This might be a need to conduct some activity consistently and reliably, so that when this activity is done by different groups of people, (within the same or different countries) the results from each group can be compared “apples-to-apples.” It may be a need to specify important guidelines, such as how loud emergency warning signals should be in offices as opposed to manufacturing environments. The experts decide when it’s time to develop a standard.

Standards are typically developed by groups of subject matter experts (SMEs). These are people with specific expertise on the topic of interest. Most standards development committees (in the US, these are referred to as “Working Groups”) are ad hoc, meaning that they assemble to write a particular standard on a specific topic. Experts are volunteers and work on an honorarium basis (unpaid). Once the standard has been approved, the SME may be dissolved and assembled again either for a revision or for writing another standard on the same topic. Decisions within the committee are typically determined by consensus, so that everyone working on the standard must agree on what is finally written.