Noise: The Safety Hazard 22 Million Workers Are Exposed to Every Year
Protecting a worker's hearing should be a high priority.
Noise is a big part of almost any workplace. But because it's so prevalent, it's easy to start getting comfortable with it and ignore the risks that come with exposure.
How many factory workers have taken off their earmuffs to have a conversation, even though loud, heavy machinery was running nearby? And how many construction workers bother putting their earplugs in if they're just going to make one quick cut with the circular saw?
If you recognize yourself in those examples, read to the end of this article. We'll go over what you need to know about noise and how to protect your hearing on the job. Once you know the risks, we're confident you'll stop putting your hearing in jeopardy.
Noise Exposure: A Widespread Problem
Noise is one of the most common occupational hazards. Unless you're a librarian or a night watchman, you're probably exposed to a fair amount of it at work.
If you work in a noisy environment, you're not alone. Approximately 22 million workers in the United States are exposed to hazardous noise levels at work. According to the CDC, 13% of workers across industries suffer from occupational hearing loss.
Sound vs. Noise
Some people will get a little philosophical and draw a distinction between sound and noise. Sound is anything we hear, while noise are only the unwanted sounds, the unpleasant ones.
But what you consider unpleasant is subjective. What we're concerned when it comes to workplace safety is something much more objective: hearing damage.
It doesn't matter if it's your favorite songs or just a sound you start to ignore after a while, if the decibel levels are high enough, it can cause harm and that's all that counts.
So, we're not going to draw a distinction between sound and noise. If it's loud enough to damage your hearing, it's noise.
Exposure to extreme levels of noise can cause permanent and irreparable hearing loss that cannot be corrected either by surgery or a hearing aid.
Short-term exposure to loud noise can also cause a temporary change in hearing or tinnitus (a ringing in the ears). Repeat exposure to high noise levels can lead to permanent tinnitus or hearing loss.
And while we all know that loud noises can lead to hearing loss, not all of us know that it can also result in physiological and psychological symptoms, such as:
- Elevated blood pressure
- Reduced productivity
- Impaired concentration
OSHA sets a legal limit for occupational noise exposure that is based on an employee's time-weighted average (TWA) over an eight-hour day. The permissible exposure limit (PEL) is 90 dBA for an eight-hour day.
NIOSH's recommendations are stricter. They recommend controlling exposure levels so that employees are not exposed to noise higher than 85 dBA (TWA for eight hours).
Rules of Thumb
When you're just going about your job, you probably don't have a way of measuring the decibel levels around you. But there are a few ways you can tell the noise level in your workplace is too loud to be endured safely without hearing protection:
- You often have to raise your voice for others to hear you
- There is a ringing or humming in your ear at the end of a work shift
- You experience temporary hearing loss after leaving work each day
How to Reduce Your Exposure to Harmful Noise Levels
There is no cure for noise-induced hearing loss. For that reason alone, you should treat your hearing protection seriously.
If you can't avoid working near loud equipment and machinery, you need to wearing appropriate hearing protection PPE.
Types of Hearing PPE
There are three types of hearing protection devices that are suitable for the workplace:
- Earmuffs: noise protection devices that are fitted over the ear
- Earplugs: stoppers made of malleable material that are inserted into the ear and normally provide better protection than earmuffs
- Semi-insert earplugs: instead of being housed in the ear, semi-inserts are fitted on a plastic band that hangs around the neck so they can be conveniently and quickly inserted and removed
(Find out How to Choose the Right Hearing Protection.)
Noise Reduction Rating
Every hearing protection device will have a noise reduction rating (NRR) listed on its packaging. The NRR will be somewhere between zero and 30, with a higher number indicating better protection (NRRs will often be expressed as a range instead of a single number, since variability in fit yields different results).
The NRR also tells you how many fewer decibels of noise you'll be exposed to while wearing the PPE. You can calculate the noise level while wearing your device using the following equation:
Noise Level in Decibels - ([NRR - 7] / 2) = Reduced Noise Level
In other words, take the decibel level of the noise in your environment and subtract by the NRR minus seven divided by two. The result will be the noise levels you're exposed to while wearing the hearing protection.
So, for example, suppose you're exposed to 100 decibels of noise in your workplace and want to know whether earmuffs with an NRR of 22 will provide you enough protection. 22 minus 7 is 15, so you divide 15 by two, leaving you with a 7.5 reduction in decibels. Or:
100 - ([22 - 7] / 2) = 92.5
While wearing your earmuffs at work, then, you'll still be exposed to approximately 92.5 dBA, which is higher than both OSHA and NIOSH's limits.
Headphones Don't Count
Noise canceling headphones make a lot of big promises about how much sound they block out, and you might find you can tolerate the noise in your workplace if you're listening to music through your earbuds. But neither of these are substitutes for PPE.
Proper hearing PPE is tested according to strict standards. Even if a headphone boasts a certain level of protection, you can't be sure that this claim has been tested rigorously.
Steps Employers Can Take to Reduce Noise Levels in the Workplace
Employers must provide their workers with the PPE they need to do the job safely, but they can also take steps to reduce the level of noise in the workplace using a combination of engineering and administrative controls.
Engineering controls could include:
- Selecting quieter tools and machinery
- Ensuring that equipment is well maintained and properly lubricated
- Placing a barrier between the source of the noise and the employees
Administrative controls can include:
- Restricting the operation of heavy machinery during less busy shifts
- Limiting the amount of time any single employee spends near a source of excessive noise
- Providing quiet areas for breaks and to get relief from the noisy environment
- Enforcing a safe distance away from noisy equipment for employees who are not operating it
Hearing Conservation Program
An effective hearing conservation program must be implemented by all employers whenever the level of noise is greater than 85 dBA for an eight-hour period (or 90 dBA for the construction industry).
The aim of a hearing conservation program is to prevent initial occupational hearing loss and preserve and protect remaining hearing, as well as equip workers with the knowledge and hearing protection devices necessary to protect them.
Protect Your Hearing
Noise-induced hearing loss isn't something anyone wants to experience. Yet, even employees trained on good hearing protection practices often fail to comply. It's easy to become a bit indifferent about your hearing protection at work, especially since the damage that comes from exposure is often gradual and might not be noticed immediately.
Stay aware of the risks and don't put your hearing on the line. Always wear the right hearing protection PPE and never take it off unless the noise is at a safe levels.
Written by Kurina Baksh
Kurina Baksh is a Health, Safety and Environment Professional from Trinidad and Tobago. As a recent graduate in the field, she is trained to analyze and advise on a wide range of issues related to her area of expertise. Currently, she is an independent consultant who develops public outreach and education programmes for an international clientele. She strongly believes that increasing public outreach and education can promote hazard awareness and ultimately save lives.