You see Jim walk in front of a lift truck and almost get hit. Why didn’t he hear it coming, like you and three other people did?
Due to decades of refusing to wear hearing protection at work and at home, Jim can’t have a conversation without other people shouting when it’s their turn to speak. He often misses out on important information. Jim knows others get annoyed with being asked to repeat themselves, so he pretends to have heard and understood.
Consequently, Jim misses many safety warning and equipment failure signals. He doesn’t hear that overloaded transformer hum, the arcing in the enclosure, the steam leak he’s about to walk through, or lift trucks coming. He’s an example of the loss of function that comes from failing to guard your hearing.
So, the answer is to always wear hearing protection when it’s noisy enough that you need to raise your voice to be heard, correct? While you should definitely do that, it won’t shield you from all the dangers arising from excess noise.
Consider the lift truck example again. This time, you’re working near a row of large stamping presses. Your use of earplugs combined with ear muffs will protect your hearing from the kind of damage Jim’s hearing experienced. But you will not be able to hear that lift truck because of the signal-to-noise ratio; all the racket from those stamping presses will drown out the noise made by the lift truck engine.
You must be alert using your other senses; in this case, only your eyes are going to prove sufficient. Scan the area ahead and to either side of you before stepping into an aisle or other trafficway.
Communication also is impaired in a high-noise environment. If you and a coworker are shouting back and forth, trying to communicate over the racket from those presses, you can’t expect that communication to be readily understood. The solution is for one of you to visually signal the other to move to a quieter area. It doesn’t need to be library-quiet, but it needs to be sufficiently removed from all the jackhammering noise from the presses that your syllables aren’t clipped off by background noise.
Similarly, audible fire alarms are notoriously ineffective in high-noise areas. Consider a generator room where the generator is running. Small room, big noise. You want to take measurements inside the control panel, which will place your back to the door of the room. Suppose an event triggers the fire suppression system and you have 10 seconds before the fire doors close.
Best practices for these kinds of environments include large warning lights located throughout the room, a sign-in with the operator station, or an attendant waiting just outside the entry. You need to be aware that you are unlikely to hear an audible warning and you need at least one of these forms of protection.
So, noisy environments provide two broad categories of danger:
- Danger to your sense of hearing. This is something you solve with the proper PPE and by reducing how much time you are in that environment.
- Neutralization of your sense of hearing by masking desirable sounds with background noise. This is something you solve before entering the area. You identify the possible dangers and then identify how to protect yourself from them.
