Construction sites can have hazardous noise levels, and they often are transient situations where different trades come to the site for short periods of time to perform their work. Depending upon the type and stage of construction, this work may be indoors, outdoors or both.
The activities and job functions at a construction site are constantly changing as the job progresses. For example, when a new building is being constructed, carpenters may build forms for the cement workers to then pour the foundation; steel workers may erect steel structures and do welding; then the building is enclosed by other workers including stucco workers, roofers and brick masons. Once the building is enclosed, carpenters, ventilation installers, electricians and plumbers begin their work, followed by drywallers, carpenters, painters and floor and ceiling workers.
Each of the different trades use very different equipment to perform their jobs, and therefore, the noise created may vary. These tasks often overlap, so workers performing jobs that are relatively quiet may be exposed to noise from the other trades working around them.
Table 1 illustrates the 10 loudest noise level tasks on the worksite. Table 1 also shows that all of the trades listed are at risk of significant noise exposure. Even electricians, a seemingly quiet trade, are susceptible to noise levels above the OHSA limit.
Controlling Noise
As mentioned above, construction site noise is varied and always changing, depending upon the activities taking place. Industrial noise often is predictable, since many industrial sites have noise characteristics that do not change from day to day. For example, a shop floor, which has production equipment and operates on a daily basis, has noise levels that generally do not change unless something in the production area changes. Such changes can range from the addition of equipment, to the changing of the materials being processed and produced, to machine malfunctions and changing of the workspace, such as the addition or removal of walls. Once the changes are made, the noise levels often return to a steady and predictable state.
Noise during construction also may be more difficult to control and more difficult to ensure that hearing protectors are being used properly because of constant changes in location, the size of the construction site and the transience of the workforce. These situations make construction noise just as hazardous as any other type of noisy environment, but far more challenging to remediate.
Noisy activities on construction sites include the use of jackhammers, dump trucks, cement mixers, cement cutters, electric saws, tamping machines and welding machines as well as noise generated from hand tools such as sledgehammers and drills.
The noise generated from these activities easily can exceed the OSHA limit of 90 dBA and require the use of hearing protection devices (HPDs). The noises may be continuous or they may be impulse noise where the noise created is of high intensity, but for a short duration. Table 2 shows the average noise level and the maximum noise level achieved by the 10 loudest tools at construction sites based on their average noise levels.
Objections to Wearing HPDs
Although noise levels on construction sites often can exceed 90 dBA, construction employees do not always wear hearing protection. Some of their most common complaints are that hearing protectors are uncomfortable, hot and create a situation where they cannot hear warning signals or fellow workers. In addition to employees finding it a nuisance to wear the appropriate hearing protection, other common issues that prevent workers from wearing their HPDs are that they are not trained properly, do not have access to the appropriate HPDs or simply are unaware of the need for hearing protection.
These objections must be overcome to protect construction workers' hearing when noise levels exceed the limits allowed. Appropriate evaluation and monitoring of the worksite, educational programs, training and adequate provision of HPDs can be a start to help make construction workers aware that many activities on the worksite have potentially hazardous noise levels.
Because of the demographics of today's workforce, employers should be prepared to provide training in several languages, if necessary. Training presentations can be purchased in various languages and can be used to fulfill some of the training requirements.
Construction workers must be educated to the fact that once they lose their hearing, it does not come back. When possible, letting the employees have a hand in choosing the product helps with compliance because they are choosing a product that they are more interested in wearing. Selecting an appropriate device that does not overprotect the user also can alleviate concerns for hearing warnings and fellow employees. Many types of hearing protectors are available to meet employee needs in terms of both compliance and user acceptance.
Bring in Professionals
Evaluating the problem requires a qualified professional such as a safety engineer, industrial hygienist or audiologist to perform the measurements and analyze the results. Either a sound level meter or a noise dosimeter should be used. If noise levels exceed 90 dBA as an 8-hour time weighted average, hearing protectors must be worn. As a minimum, each worksite must comply with OSHA regulation 1926.52 and any state or local regulations.
Although not explicitly required by the OSHA construction regulation, a program that includes annual audiograms, training and recordkeeping is recommended. OSHA also requires that noise levels be reduced through engineering methods and administrative controls, before the employer turns to the use of HPDs. However, since construction situations are so dynamic, many times the only practical means of noise control is with personal protective equipment.
HPDs available for use on construction sites range from disposable and reusable earplugs to semi-aural devices (banded products) and earmuffs. An employer only should provide choices to the employee that will meet the needs of the work situation in terms of the amount of attenuation, hygiene and other factors. Making the right choice may require the help of a health and safety professional such as an industrial hygienist or an audiologist.
To choose the appropriate HPD, the employer must consider several factors:
-
The noise level and even the frequency of the predominant noises may need to be considered. This may require the assistance of a health and safety professional.
-
Next, maintenance of the hearing protectors must be considered. Construction sites often can be very dirty, and therefore, employees may want a product that is easy to maintain or requires little or no maintenance, such as earplugs or hearing bands.
-
Finally, a very important factor is how the hearing protector interacts with other personal protective equipment such as hard hats, eye protection and welding hoods. The hearing protector should not interfere in any way with other safety devices. If it does interfere with other safety devices, an overall assessment of personal protective equipment might be needed.
Before choosing the right hearing protector, it must be determined whether or not hearing protection devices are necessary. This requires recognizing that a noise problem may exist, evaluating the extent of the potential problem and controlling it.
Even though a construction site constantly is changing, employees still can be protected from dangerous noise levels. A well-developed and implemented plan that includes input from employees not only can lead to a safer work environment and healthier employees but also a reduction in the company's liability.
Employers are advised to refer to OSHA's noise in construction standard, 29 CFR1926.52. If feasible, though not required, the construction employer may wish to consider OSHA's general industry noise standard — 29CFR1910.95 — which is a more in-depth program and provides more guidance in protecting workers.
(Author's Note: The tables in this article reflect the results from a survey of worksites, which may or may not differ from your own. They should only be used as a reference.)
Jeff Birkner is a certified industrial hygienist and holds an M.S. degree in environmental health sciences, a B.A. in biology from New York University and a Ph.D. in environmental health sciences from UCLA. He has more than 25 years experience in the practice of industrial hygiene. He has done laboratory research, worked in public health and private industry. Birkner has worked for Moldex-Metric for 19 years and currently is vice president of Technical Services. He served as president of the International Society for Respiratory Protection from 1991 to 1993 and sits on various ANSI committees, is a member of the respirator committee of the AIHA and presently acts as vice chair for the respiratory standard group for International Safety Equipment Association (ISEA). He can be reached via e-mail at JeffreyB@moldex.com.
Table 1: 10 Loudest Tasks
Tasks (Trade) Average Noise Level (dBA) Maximum Noise Level (dBA) Installing TrenchConduit (Electricians) 95.8 118.6 Operating Work
Vehicle (Bricklayers) 98.0 116.7 Operating Manlift
(Operating Engineers) 98.1 117.6 Welding, Burning
(Ironworkers) 98.4 119.7 Operating Scraper
(Operating Engineers) 99.1 108.6 Demolition
(Laborers) 99.3 112.1 Laying Metal Deck
(Ironworkers) 99.6 119.9 Grinding
(Masonry Trades) 99.7 118.6 Operating Bulldozer
(Operating Engineers) 100.2 112.5 Chipping Concrete
(Laborers) 102.9 120.3
*Source: Department of Environmental and Occupational Health Sciences, School of Public Health and Community Medicine, University of Washington
Table 2: 10 Loudest Tools
Tools Average Noise Level (dBA) Maximum Noise Level (dBA) Welding, Cutting Equipment 94.9 122.8 Other Hand Power Tool 95.4 118.3 Hand Power Saw 97.2 114.0 Screw Gun, Drill Motor 97.7 123.7 Rotohammer 97.8 113.5 Chop Saw 98.4 117.7 Rattle Gun 98.4 131.1 Stationary Power Tool 101.8 119.8 Powder Actuated Tool 103.0 112.8 Chipping Gun 103.0 119.2*Source: Department of Environmental and Occupational Health Sciences, School of Public Health and Community Medicine, University of Washington