One morning this week, I received a text message from one of my favorite former clients. In summary, she wanted to know whether or not employees working in noisy areas needed to wear hearing protection, such as ear muffs, formable inserts (plugs), or ear caps. Later on that same day, I received an almost identical question from another client.
The answer isn’t as simple as you might think. Before you can answer the question, you need to know just how noisy the area in question is.
The OSHA requirement in question is 29 CFR 1910.95 – “Hearing Conservation”. The regulation requires that the employer evaluate employees’ exposure to noise. The best way to do this is with a device called a “noise dosimeter”, although it can be done with a simpler device called a “Sound Level Meter” or “SLM” too. Commonly, a noise dosimeter is a device, roughly the size of a pack of cigarettes, with a wired microphone. The noise dosimeter is worn by employees, with the microphone worn on the collar of the shirt, near the ear. The dosimeter takes several noise readings per second over the course of several hours, and logs all of them. At the end of the test, the computer will tally all the readings and calculate a “Time Weighted Average” or “TWA”.
If the Time Weighted Average indicates that employees are, or may be exposed to 85 dBA (Decibels measured on the A scale) but less than 90, the employer will be expected to develop a hearing conservation program. While the program does not specifically need to be written, it should be. The program must include procedures for monitoring noise exposure levels of all employees covered by the program, annual training on noise for affected employees, providing adequate hearing protection to affected employees and encouraging them to use it, and providing annual audiometric exams (hearing tests) to affected employees.
If the results indicate that employees are, or may be exposed to 90 dBA or more, then the employer must research and implement feasible engineering or administrative controls to reduce employees’ noise exposures, and must begin to require the use of adequate hearing protection. Keep is mind, noise is measured on a logarithmic scale. That is to say, noise levels double every five decibels, so the difference between 85 and 90 is a sizable jump, double in fact.
Also keep in mind that in Minnesota, noise is considered a physical agent, which is covered by the hazard communication standard, so even if the employees aren’t exposed to 85 dBA, you will be required to address noise in your hazard communication program and training if their exposures “approximate” 85 dBA!
If you have questions about noise, hearing conservation, hearing protection, or any other health, safety, or OSHA question, please call me at (612)597-6463 or email firstname.lastname@example.org.