Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and no longer represents OSHA Policy. It is presented here as historical content, for research and review purposes only.

Noise/Hearing Conservation

Occupational exposure to noise levels in excess of the current OSHA standards places hundreds of thousands of workers at risk of developing material hearing impairment, hypertension, and elevated blood pressure levels. (1,2) Workers in some industries (i.e., construction, oil and gas well drilling and servicing) are not fully covered by the current OSHA standards and lack the protection of an adequate hearing conservation program. (3) Occupationally induced hearing loss continues to be one of the leading occupational illnesses in the United States. (4) OSHA is designating this issue as a priority for rulemaking action to extend hearing conservation protection provided in the general industry standard to the construction industry and other uncovered industries.

Hazard Description

According to the U.S. Bureau of the Census, Statistical Abstract of the United States, there are over 7.2 million workers employed in the construction industry (6% of all employment). (5) The National Institute for Occupational Safety and Health's (NIOSH) National Occupational Exposure Survey (NOES) estimates that 421,000 construction workers are exposed to noise above 85 dBA. (2) NIOSH estimates that 15 percent of workers exposed to noise levels of 85 dBA or higher will develop material hearing impairment. (6)

Research demonstrates that construction workers are regularly overexposed to noise. The extent of the daily exposure to noise in the construction industry depends upon the nature and duration of the work. For example: rock drilling--up to 115 dBA; chain saw--up to 125 dBA; abrasive blasting--105 to 112 dBA; heavy equipment operation--95 to 110 dBA; demolition--up to 117 dBA; and needle guns--up to 112 dBA. Exposure to 115 dBA is permitted for a maximum of 15 minutes for an 8-hour work day. No exposure above 115 dBA is permitted. (3) Traditional dosimetry measurement may substantially underestimate noise exposure levels for construction workers since short-term peak exposures which may be responsible for acute and chronic effects can be lost in lower full-shift time-weighted average measurements. (7, 8)

A recent study of construction noise in Ontario found average noise levels ranging from 93.1 dBA to 107.7 dBA. Limited impulse noise sampling indicated that overexposure to this type of noise may also occur. Tools and equipment were found to be the sources of the noise. For workers other than heavy equipment operators, the use of electric or pneumatic power tools for short periods resulted in the overexposure. (9) A study of highway construction using task-based sampling methods to characterize exposures found wide-spread overexposure to noise and lack of hearing protection use. (8)

A recent study of construction laborers found noise exposure and noise-induced hearing loss posed an increased health risk to these workers. (10) Noise exposure in construction workers can lead to hearing loss and balance dysfunction. A study of construction workers found that occupational noise exposure made iron workers prematurely deaf and impaired their balance. Serious and deadly falls on construction sites may be related to noise-induced balance dysfunction and impaired equilibrium. (11) Elevated noise levels pose an additional threat of injury or death to workers by reducing communication among them and between supervisors and workers and by reducing the effectiveness of audible warning devices. (1) Several recent studies have documented an apparent association (synergistic effect) between worker exposures in construction and other industries to solvents and occupationally related hearing loss. (12, 13)

There are a variety of control techniques documented in the literature to reduce the overall worker exposure to noise. Such controls reduce the amount of sound energy released by the noise source, or divert the flow of sound energy away from the receiver, or protect the receiver from the sound energy reaching him/her. For example, types of noise controls include proper maintenance of equipment, revised operating procedures, equipment replacements, acoustical shields and barriers, equipment redesign, enclosures, administrative controls, and personal protective equipment. (14) Current Status

Under OSHA's general industry standard, feasible administrative and engineering controls must be implemented whenever employee noise exposures exceed 90 dBA (8-hour time-weighted average (TWA)). In addition, an effective hearing conservation program (including specific requirements for monitoring noise exposure, audiometric testing, audiogram evaluation, hearing protection for employees with a standard threshold shift, training and education, and recordkeeping) must be made available whenever employee exposures equal or exceed an 8-hour TWA sound level of 85 dBA (29 CFR 1910.95). Similarly, under the construction industry standard, the maximum permissible occupational noise exposure is 90 dBA (8-hour TWA), and noise levels in excess of 90 dBA must be reduced through feasible administrative and engineering controls. However, the construction industry standard includes only a general minimum requirement for hearing conservation and lacks the specific requirements for an effective hearing conservation program included in the general industry standard. (20 CFR 1926.52)

The National Institute for Occupational Safety and Health (NIOSH) and the American Conference of Governmental Industrial Hygienists (ACGIH) also have recommended exposure limits (NIOSH: 85 dBA TWA,115 dBA ceiling; ACGIH: 85 dBA). (6, 15)

NIOSH is currently developing a Risk Assessment on Noise, and a revised Criteria Document on Occupational Noise Exposure. A NIOSH Document entitled "Compendium of Hearing Protection Devices" was recently updated. (16)

In Healthy People 2000: National Health Promotion and Disease Prevention Objectives, the U.S. Public Health Service set a goal to reduce to no more than 15% the proportion of workers exposed to an average daily dose level that exceeds 85 dBA. (Goal 10.7)

The United Kingdom's Health and Safety Commission and Executive identified noise as one of their top ten areas of attention on their Plan of Work for 1994/1995.

The Advisory Committee on Construction Safety and Health (ACCSH) adopted a report from the Work Group on Health and Safety of Women in Construction (HASWIC) which called for public meetings, and other data/information gathering activities to increase awareness about and to address gender-related issues and their impact on safety in the construction industry. The Work Group suggested exposure to chemicals and noise among other examples of gender-related issues which they feel should be addressed. (Report adopted 12/9/94) Rationale

Rulemaking action to extend noise and hearing conservation protection to workers in the construction industry and other uncovered industries meets the criteria for designation as an OSHA priority. There are a very large number of construction workers exposed to noise; the health effects of noise exposure are serious; there is extensively documented scientific evidence of the risk; and there are a variety of available and feasible control methods to reduce worker exposure. There is also considerable interest within both business and labor to work with government agencies to find effective ways to reduce exposure to noise above 85 dBA and to protect workers. References

  1. 46 FR 4077-4179, January 16, 1981. Occupational Noise Exposure, Hearing Conservation Amendment. Corrections 48 FR 9738, March 8, 1983.
  2. NIOSH (July 1990). National Occupational Exposure Survey. Unpublished Provincial Data.
  3. 29 CFR 1926.52
  4. MMWR (March 28, 1986). Morbidity and Mortality Weekly Reports: Leading Work-Related Diseases and Injuries - United States. Vol. 35 No. 12:185-188.
  5. U.S. Bureau of the Census, Statistical Abstract of the United States: 1994 (114th edition.) Washington, D.C., 1994. p 412.
  6. NIOSH (1972). Criteria for a Recommended Standard: Occupational Exposure to Noise. (Publication No. 73-11001).
  7. Stephenson M (1995). Noise Exposure Characterization via Task Based Analysis. Proceedings, Hearing Conservation III/XX. Spectrum, Volume 12, Supplement 2, 63-71.
  8. Greenspan CA, Moure-Eraso R, Wegmen DH, and Oliver C (1995). Occupational Hygiene Characterization of a Highway Construction Project: A Pilot Study. Applied Occupational Environmental Hygiene (10)1: 50-58.
  9. Sinclair JDN, Haflidson WO (1995). Construction Noise in Ontario. Appl Occup Environ Hyg 10(5). May 1995. pp. 457-460.
  10. Burkhart G, Schulte PA, Sieber WK, et al. (1993). Job Tasks, Potential Exposures, and Health Risks of Laborers Employed in the Construction Industry. Am. J. Ind. Med. 24(4):413-425.
  11. Kilburn KH, Warshaw RH, Hanscom B. (1992). Are Hearing Loss and Balance Dysfunction Linked in Construction Iron Workers? Br. J. Ind. Med. 49(2):138-141.
  12. Morata TC, Dunn DE, Kretschmer LW, Keith RW (1993). Effects of Occupational Exposure to Organic Solvents and Noise on Hearing. Scand. J. of Work, Environ. and health. 19(4): 245-254.
  13. Morata TC, Dunn DE, Sieber WK (1994). Occupational Exposure to Noise and Ototoxic Organic Solvents. Arch. of Environ. Health. 49(5): 359-365.
  14. NIOSH (1979). Industrial Noise Control Manual, Revised Edition. (Publication No. 79-117).
  15. ACGIH (1994). American Conference of Governmental Industrial Hygienists: 1994-1995 Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices.
  16. NIOSH: Compendium of Hearing Protection Devices. (Publication No. 95-105).

NOTICE: This is an OSHA Archive Document, and no longer represents OSHA Policy. It is presented here as historical content, for research and review purposes only.