Continuous, repetitive exposure to a noise level higher than 90 dB leads to hearing loss.
The impact of repetitive noise is often underestimated. Yet it’s among the most damaging factors for your hearing health. In this article, we demystify how noise affects worker health and show you 3 safety solutions to reduce the noise generated when you use compressed air.
“In Québec, more than 400,000 workers are exposed to excessive noise levels at work. What’s more, according to Statistics Canada, 42% of Canadians between the ages of 16 and 79 are working or have worked in a noisy environment. Of those, only 22% frequently use hearing protectors, while 39% never do.” Source: Lobe, 2020.
In factories and other work settings, noise levels don’t add up, but combine. If two noise sources emit 80 dB, the measured exposure level will be 83 dB. Why? Because the brain just can’t distinguish the intensity of staccato sounds that hammer the eardrum. And if it can't detect them, it can’t adapt to them. Repetitive noise is perceived as a continuous sound, which explains why prolonged exposure represents such a hazard to hearing health.
In Québec, the legally tolerated noise level is 90 dB. That’s because exposure to a noise level higher than 90 dB for 8 hours a day leads to hearing loss. It’s scientifically proven. The employer is required to provide hearing protection when the sound level exceeds the legally permitted level deemed to be danger-free.
“Québec is the most permissive province in terms of noise in the workplace. The maximum exposure level for eight hours of work is 90 dB(A) in Québec, versus 85 dB(A) in all other provinces and territories or 87 dB(A) for the federal government.” Source: Le Journal de Québec, 2019.
The following table shows the acceptable level of noise exposure for a Québec worker, based on the duration of noise exposure (A-weighted decibels as measured by a standard sound level meter with the data indicated).
Duration of exposure and acceptable level
|Duration per day in hours
||Sound level in dB(A)
|0.25 or less
Source : OSHA 29 CFR PART 1910.95 (b)(2)
CSST L.R.Q., c. S-2.1, r.19.01 Section XV, 131.
To represent the noise tolerance level, the diagram below illustrates the severity of various noise levels with examples from everyday life. Remember that a high noise level is a threat to hearing health when exposure is continuous and repetitive.
90 dB is the approximate decibel level where extended exposure to noise can cause real damage to the inner ear and promote hearing loss.
Noise sources in factory or plant settings
Where, exactly, does noise come from in a factory or plant? The source of noise varies depending on the applications and industry. Noise is generated regardless of the energy source used. To identify and measure this noise, start with the largest machines and work your way down to the smallest, visually speaking. First, consider heavy equipment, large machinery and different industrial processes (ejection of parts, cleaning, drying, die-cutting, molding, etc.), then think of the many tools that are used (rotary, percussion, air suction or ejection, etc.). Finally, there’s every noise made by the slightest operation and manipulation (reels, balancers, forklifts, doors, etc.). Noise adds up. In a pneumatic system, we often think of blow guns, which are heavily regulated by OSHA for noise (read the blog post Prevent Hearing Loss by Using a Silent Blow Gun to find out more)... but do you know what noise source is even more harmful? Pneumatic valves. For example, a valve with ½ in. ports used to control a pneumatic cylinder at 3 cycles per second can produce a noise level equivalent to 92 dB of continuous sound? Since the legal level is 90 dB, that’s pretty noisy.
who work in noisy environments first develop ringing in their ears (tinnitus), followed by an inability to tolerate loud sounds (hyperacusis) and, finally, hearing loss. The level of damage caused by noise depends on the worker's individual predisposition as well as the intensity (volume) and duration of the noise exposure. When hearing is lost, the loss is usually irreversible. That loss can be detrimental to the person’s social interactions and communication, making it hard for them to understand what people are saying.
Noise control is a challenge that all industries need to meet in order to provide workers with a safe environment. It’s a must, whether or not the noise is related to compressed air. Taking the right measures means you’ll reap many benefits:
There are different ways to prevent hearing loss. Workers are, at the very least, required to wear the personal protection stipulated by law. Wherever possible, reduce the noise level at source. Be proactive and discover our 3 safety solutions that can reduce the noise generated by the use of compressed air.
We offer different models of pneumatic mufflers. They’re perfect for quietly evacuating compressed air from air valves, pneumatic motors, and pneumatic impact tools. Some of the most harmful noise that occurs when using a compressed air system is created when compressed air is exhausted from pneumatic valves. Mufflers suppress the noise of air exhaust from pneumatic valves and help preserve hearing health in the workplace.
||To find out more about this hearing health solution, check out the blog post titled Reduce Noise at Your Plant with Pneumatic Mufflers.
Blow guns are used in many industries to clean, dry and remove dust from work surfaces, as well as to eject and dry parts in a manufacturing process. We offer a wide selection of blow guns that comply with the acceptable noise level for workplaces under OSHA and other health and safety regulations. What sets AIRPRO blow guns apart is how silent they are compared to similar brands available in the market. They limit the noise generated in a work setting when a number of devices, pieces of equipment and tools are being used.
||To find out more about this hearing health solution, check out the blog post titled Prevent Hearing Loss by Using a Silent Blow Gun.
Some industrial processes (e.g., ejecting parts, cleaning, drying, die-cutting, molding, fume exhaust, and chilling) require the use of air amplifiers. Not only do these accessories save on energy, they also reduce the noise level associated with compressed air use. Certain amplifier and air curtain models reduce noise by up to 50 dB.
||Download our brochure on Safety and Prevention Solutions for Compressed Air (PDF) to see our products for a range of safety issues in the workplace.
Udem nouvelles. Une équipe étudiera les effets du bruit sur le système auditif des travailleurs, November 1, 2019.
Journal de Québec. Les cas de surdité au travail ont quadruplé en 10 ans, February 25, 2019.
Institut national de la santé publique du Québec. Le bruit en milieu de travail : une analyse des coûts pour le régime d’indemnisation (PDF), October 2007.