Ludwig van Beethoven’s ninth symphony (the Choral) is considered to be his finest work. Premiered in 1824, he had to be turned around at the end of conducting the symphony because his hearing loss was so severe he couldn’t hear the audience’s thunderous applause. Beethoven’s hearing loss is attributed to typhus disease, lead poisoning, and even his habit of immersing his head in cold water to stay awake.  In today’s industrialized world, the roar of machinery can progressively lead to noise-induced hearing impairment/loss as one of the most common occupational illnesses.
In 1974, OSHA published a proposed occupational noise standard, which included a requirement for employers to provide a hearing conservation program for workers exposed to an 8-hour time-weighted average of 85 decibels (A scale) or more. The hearing conservation program provision was later adopted in the early 80’s with other amendments. More recently, OSHA has developed a Noise and Hearing Conservation e-Tool that is comprised of the following four sections.
I. What is considered “noise” and what are the potential health effects?
II. What standards limit and control noise exposure?
III. How do I evaluate noise exposure?
IV. What constitutes an effective hearing conservation program?
Section III on evaluating noise exposure cites these indications of a problem:
- When noise levels are above 80 decibels (dB), people have to speak very loudly.
- When noise levels are between 85 and 90 dB, people have to shout.
- When noise levels are greater than 95 dB, people have to move close together to hear each other at all.
Beethoven’s gradual deafness began when he was in his twenties with a severe form of tinnitus that prompted him to avoid conversations. This same social avoidance can occur when workers exposed to excessive occupational noise suffer increasing hearing impairment, underscoring the importance of hearing conservation for hearing conversation.
Check out the MEMIC Safety Director for a sample Hearing Conservation Program and recorded webinar on occupational noise exposure.
References: 1. Wikipedia.com