DEPARTMENT OF ENVIRONMENTAL HEALTH

Noise and the Construction Industry

As anyone who has ever worked in or around the construction industry can attest, construction work is noisy. However, until recently very little research has been done to find out just how noisy this type of work can be, and how common high noise exposures are in construction. This fact sheet will introduce some basic concepts of noise exposure, noise-induced hearing loss (NIHL), and what is being done to prevent permanent hearing damage in construction workers.

Noise Exposure

Noise is simply unwanted sound. Noise levels are measured on a scale called decibels (dBA), which matches the response of the human ear. Normal conversation produces a noise level of 60 dBA, while power tools often produce levels between 90-110 dBA. If two people standing an arm’s length apart must raise their voices to talk, the noise level is over 85 dBA. Noise levels above 140 dBA cause pain immediately and produce hearing damage. Decibels are a logarithmic scale, meaning that 100 dBA is 10 times as loud as 90 dBA, 100 times as loud as 80 dBA, and 1000 times as loud as 70 dBA!

The Effects of Noise on Hearing

Noise exposures that are loud enough and last long enough can cause noise-induced hearing loss (NIHL). NIHL is a permanent and irreversible condition in which the nerves inside the inner ear that detect sound become damaged and no longer work properly, resulting in a loss of hearing ability. This damage can result from a single very noisy event (like an explosion), or from repeated exposure to lower noise levels (like years of working around construction noise without hearing protection). Workers who have suffered NIHL often become socially isolated because they can’t communicate easily with others, and may not be able to hear audible warning signals, which can lead to accidents and injuries.

Noise Exposure Laws in Washington State

Washington has set a Permissible Exposure Limit (PEL) for construction workers exposed to noise in the state of Washington. This PEL allows workers to be exposed to an 8-hour average noise level up to 85 dBA. Workers exposed to average noise levels above the PEL must use hearing protection, and must be enrolled in a Hearing Conservation Program (HCP) in which they receive annual hearing tests and training on how to prevent NIHL. Unfortunately, the hearing conservation standard has been only partly implemented in the construction industry. As a result, many construction workers in Washington are not enrolled in effective HCPs, and often suffer hearing loss during their careers.

Noise in the Construction Industry

Recent studies at the University of Washington found that 40% of all measurements made on carpenters, ironworkers, laborers, and operating engineers were over the Washington PEL (85 dBA). Twenty-four percent of measurements on a ‘quiet’ trade, electricians, were also over the Washington PEL. Furthermore, electricians were unlikely to use hearing protection, such as earplugs or earmuffs, even when exposed to high levels of noise.

Over 21% of all accepted worker’s compensation hearing loss claims in Washington were filed by construction workers, who make up only 5% of the state’s workforce. Obviously, workers in certain trades are being exposed at high levels, and are suffering enough hearing damage to file hearing loss claims. But little is known about how fast this damage occurs, or how bad the average hearing loss is. NIHL is a completely preventable disease, but more research is required to identify the best approach to preventing this widespread problem.

Current Research on Noise and Hearing Loss in Construction Workers

The University of Washington is currently conducting a multi-year research study to measure noise exposures and hearing loss experienced by construction apprentices. This study will provide useful information on how construction workers suffer hearing loss, and what steps can be taken to prevent this loss. Construction workers enrolling in an apprenticeship program in 1999 or 2000 are eligible to participate in the study. Participating apprentices will have their hearing levels and noise exposures measured once a year over a 4-year period, and will be paid for their time. Participation in this study is voluntary, and will not interfere with work activities. Apprentices will get the results of their personal noise exposures and hearing tests. For more information on noise exposure and hearing loss in the construction industry or about the UW hearing loss study, contact: