Why Sound Matters
And why we refuse to wear hearing protection.. even if it hurts us.
In the days of the caveman
Hearing, from an evolutionary perspective, is key to our survival. It's our first warning signal to being approached by a bear, to being stalked by a tiger. The cries of help reach our ears far quicker than the smell of smoke in the event of a fire. And our ears are always working, even when we sleep, so it's our body's primary 24/7 alerting function. The low frequencies determine how loud we hear things, such as people walking up behind us, the purr of a car's engine as it approaches, people calling our names.
This is the reason why your ears naturally protect the lower frequencies of sound, burying the ear hair cells (cilia) responsible for picking up these signals deep in your cochlear.
Hearing is also responsible for our balance. The vestibular system consists of 3 semicircular canals, which basically act as our body's internal level gauge. Blocking your hearing (through personal protection devices or nasal congestion) means throwing these two systems out of whack. Your body freaks out because it's no longer able to hear warning signals, and is no longer as capable of maintaining balance!
This is the reason why many people are reluctant to wear hearing protection. And for good reason. If you're working on a construction site next to a busy street or on top of a 5 storey building, it stands to reason why you'd want to keep your wits about you.
The second reason is because hearing is essential for communication. It's really hard to talk to someone with Class 5 earmuffs on. So you often find people taking off their hearing protection "for a quick chat". Problem is, we are sometimes in environments that are so noisy, that the 5 minutes without hearing protection on causes your hearing to degrade. Don't forget that just 30 seconds at 120 dB (the noise produced by an average chainsaw) uses up your "noise dose", so anything more is harmful to your hearing!
There is a way around that.
You can use electronic hearing protection, where radio systems are inbuilt into earmuffs so you can continue to talk to other team members while continuing work. That solves the communication problem, but doesn't address the warning/balance problem. It also means that you're fighting noise with more sound, and some team members might end up boosting the radio comms signal to (ironically) dangerous levels to keep communicating.
For workplaces, we recommend (in very loud environments above 110 decibels) double protecting with acoustic filtered earplugs. This means that you're always wearing an acoustic filtered earplug on site, while wearing earmuffs on top of that for full protection when operating heavy machinery. Depending on your environment, the acoustic filtered earplugs alone might not be enough to completely mitigate the risk of hearing loss over a full day's work. But it means that when you take your earmuffs off for a "quick chat" or to scale a building, you're still hearing your environment at a safer, more comfortable volume, while retaining your internal balance and warning system.