Everyone knows that construction sites are noisy. From roaring dozers and reverse signals to drills and hammers, the presence of noise is almost as given as the presence of hard hats or safety vests. But noise pollution and hearing protection isn’t as talked about as other on-site dangers or safety hazards. It’s time to change that conversation and bring the dangers of exposure to noise to light.
Noise pollution is defined as regular exposure to elevated sound levels that can cause adverse effects for humans and other living organisms. Noise levels are measured in decibels – or dB. In general, noises between 30 – 60 decibels are concerned ‘acceptable”. The average human voice or conversation is about 60 dB. Vacuum cleaners, office noise, etc usually sit around 70 – 75 dB. As a rule, noises above 85 dB are considered dangerous.
Common examples of noise pollution include construction work, public concerts, highways, a neighbourhood party and other louder events that interrupt the usual ambiance of an environment.
Over time, there have been more studies done on the impact of long-term exposure to excessive noise and noise pollution. Prolonged exposure to noise can cause:
Hypertension means elevated blood pressure. Those that live in noisier areas have a 6% higher risk of developing hypertension than those who live on quieter streets. High blood pressure can make someone a greater risk for heart attack, heart failure or stroke since overtime it puts added stress on your heart and circulatory system.
Noise is known to affect someone’s ability to stay focused and to think clearly. Prolonged exposure to noise can have lasting effects on a person’s emotional state, level of attention and ability to focus. This is especially dangerous on construction sites where spatial awareness and focus can help prevent serious injury or death.
Along with this, continual noise causes the same physical reaction in humans as stress. This is part of the reason that exposure can impact a person’s mental state and stability.
Almost all of us have walked out of a loud concert with ringing ears while responding, “WHAT?” to your friends for the rest of the night. The temporary loss or impact on hearing is a symptom of excessive noise. Over time, if the noise is above the danger level and lasts over time, your ears’ ability to bounce back is affected.
The part of the ear that is impacted by noise is the inner ear or cochlea. There are a number of hair cells and membranes in this part of the ear that can be damaged or can die from loud noises.
On average you have about 16,000 hair cells in your cochlea. These hairs vibrate and actually allow your brain to detect sound. Up to 50% of these hairs can die or be damaged before hearing loss can be detected with a hearing test.
A common metaphor of damage to these hairs is walking on grass. If you walk over once and the blades are flattened, they will spring back up. Over time and constant use, however, grass will flatten and die permanently. It’s the same with the hairs in your ears.
Chainsaws, leaf blowers and other hand-held machines sit around 105 – 115 dB. Motorcycles, crowds, sirens, etc can all range from 90 to up to 140 dB. According to the American Speech-Language-Hearing Association, Listening to sounds at this 85 dB range for more than 8 hours at a time can cause hearing loss. For every 3 dB above that 85 range, that time cuts in half.
For example, being exposed to something at 85 dB has an 8 hour limit. At 88 dB, that limit is cut down to 4 hours. At 91 dB, that time is already down to 2 hours
According to a study by the University of Washington School of Public Health and Community Medicine, the average full-shift noise level for operators is 84.6 dB- just under the 85 standard. About 46% of a day on-site exposes contractors to levels of 85 dB.
Almost all types of equipment have an average noise level of over 85 decibels. How many equipment operators wear hearing protection every day on the job? If the answer isn’t, “all of them” then it’s not enough.
Being in an environment with a high level of noise is a reality of the job. But that doesn’t mean that construction workers need to be at risk of hearing loss, permanent damage or any other risk associated with noise exposure.
It’s estimated that over half a million construction workers are exposed to dangerous levels of noise every day. Unfortunately, there is not nearly as much incentive to promote hearing protection and education about noise exposure as there is for other workplace hazards. One statement from the library of Occupational Safety and Health rated the use of hearing protection in the US as “very poor”.
The normalization of hearing protection on site should be a larger movement across North America. Not only is it incredibly simple but the lasting effects are so positive. Most sites do have access to ear protection or disposable earplugs. But the education about why it matters and the dangers of not using it are not really talked about.
Until access to hearing protection is paired with education for why it matters, not many people may feel compelled to use them. Unfortunately, the lack of compliance with wearing hearing protection has forced health and safety groups to look for other ways to protect contractors against noise damage.
Limiting the use of machinery in a day or leaning on new technology such as electric-powered construction equipment that is quieter to run could help address the issue at the source. But these changes and adaptations will take time. It really is the normalization of wearing hearing protection that will save contractors' hearing abilities.
Whether it’s being more aware of how long you spend exposed to high levels of noise or making earbuds a normal part of your PPE routine, it’s important to remember that hearing is something we often take for granted. In order to protect it, you have to take action. And if not, the impact will sneak up on you without you realizing it.
Protect yourself. Protect your ears. Be aware of what noise pollution is and the dangers of it.