Noise in the Arts and Entertainment Industry
Every day, we encounter sounds in our environment, like the roar of a crowd erupting during a live concert, the explosive crash of a stunt sequence on a movie set, or the constant chatter of walkie-talkies coordinating cast and crew behind the scenes. Normally, these
sounds are at safe levels that don’t damage our hearing. However, sounds can be harmful when they are too loud, even for a brief time, or when they are both loud and long lasting. Overexposure to sound can damage sensitive structures in the inner ear and cause noiseinduced hearing loss (NIHL).
Noise is defined as loud or unwanted sound that causes disturbance. To understand how
noise can damage our hearing, we have to understand how we hear.
How we hear
Hearing depends on a series of events that change sound waves in the air into electrical signals. First, sound waves enter the outer ear and travel to the eardrum, causing it to vibrate. These vibrations then travel through the middle ear to the inner ear and into the cochlea. The cochlea is filled with a fluid that moves in response to the vibrations coming from the middle ear. As this fluid moves, it sets into motion 25,000 tiny hair cells in the cochlea. These hair cells transform the vibrations into electrical impulses that then travel along the
auditory nerve to the brain, where they are interpreted as sound.
Most NIHL is caused by damage to and the eventual death of these hair cells. Human hair cells in the cochlea don’t grow back, so NIHL is permanent and irreversible. NIHL can have major impacts on our quality of life. Noise is a serious and widespread problem
in many workplaces. Over time, if noise from machinery, processes, and equipment is too loud, it can cause permanent hearing loss in
workers. The arts and entertainment industry is no different.
Hearing Loss Prevention and Hearing Testing
Hearing Loss Prevention and Hearing Testing Webinar is designed to help BC’s arts and entertainment professionals better protect their hearing while working in high-noise environments.
Film production
Let’s walk through a film set and listen for work activities that could be a source of noise hazards.
Craft services, security, and transportation workers are generally stationed outside the set. Noise hazards in this area may include the chorus of generators powering the production and traffic noise from vans or forklifts, which can be as loud as 85 decibels (dBA). These are examples of continuous noise, which remains constant and stable over a given time period. In British Columbia workplaces, the allowable limit for noise exposure is 85 dBA, as a time-weighted average over an eight-hour period.
Moving on to the arts department, noise hazards that mostly affect the construction crew come from saws or nail guns used to build the set, as well as general noises from material movement and assembly. For painters, power sanding, paint mixing, and spray painting can be noise hazards. In the makeup and costumes department, there might be loud hair dryers or exhaust fans.
Depending on the scene and the equipment used, anyone on set can be exposed to hazardous noise. Special effects involving explosions, fire, guns, and crashes can be very loud. These are examples of impact noises, which are sudden, sharp sounds of short duration. Impact noises must not exceed a peak sound level of 140 dBC
Live events
In the live events industry, most people would not consider many of the sounds they hear to be noise. In fact, people pay good money to enjoy the sounds of a concert. They may even generate a lot of sound themselves by clapping and cheering. However, many concerts and other live events can exceed safe sound levels. If you have ever had muffled hearing or ringing in your ears after a concert, you have experienced a temporary threshold shift in your hearing. Your hearing generally returns to normal after several hours, but your ears can handle only so many temporary threshold shifts before this temporary damage becomes permanent.
Noise exposure limits
Employers must measure noise exposure if workers could be exposed to hazardous noise or if the employer already knows that workers will be exposed to noise levels greater than 82 dBA (called the “action limit”). Measuring and calculating noise exposure can be difficult. Often the best way to get accurate noise measurements is to hire a professional such as an industrial hygienist or acoustical engineer to conduct an occupational noise exposure survey.
If noise levels exceed noise exposure limits, the employer must implement a hearing conservation program to reduce worker exposure to noise and prevent NIHL. The program must include specific elements, such as noise measurement, hearing tests, hearing protection, and noise control measures, as required by section 7.5 of the Occupational Health and Safety Regulation.
Control measures
The best options are to eliminate the noise source or to substitute it with a quieter process. However, elimination or substitution are not always possible. For continuous noise, engineering controls can be used to modify or replace equipment to make it quieter. Engineering controls may include other physical changes at the noise source or along the transmission path to reduce the noise level at the worker’s ear.
Engineering controls may not be effective for impact noises such as explosions or crashes. Instead, administrative controls can be used, such as making changes to worker schedules or their location relative to the noise source to reduce or eliminate exposure. Even though everyone wants to witness a cool explosion scene, non-essential workers could be asked to vacate the film stage or set, or to observe the shot from a further distance.
Although it may not be a popular control, concert halls or arenas can turn down the music a little. A 3 dBA reduction actually cuts the sound pressure level in half.
Although personal protective equipment (PPE) is the least reliable control, it may be used if other controls are not practical, or in addition
to other controls. PPE such as hearing protection must fit properly and be suitable for the work activities and noise exposure levels. Workers must be trained to wear and maintain their hearing protection properly.
This article is written by written by Adrian Fung, Taryn Toic, and Mona Shum.
