The National Institute for Occupational Safety and Health s (NIOSH) Health
Hazard Evaluation and Technical Assistance (HETA) program responds to
approximately 400 requests per year from employers, employees, employee
representatives, other Federal agencies, and State and local agencies to
examine suspected hazards in the workplace.
The typical HETA response to a request for assistance results in an evaluation
of whether chemical, physical, biological, or other agents are hazardous as
used or found in the workplace followed by the development of recommendations
for control procedures, improved work practices, and medical programs to
reduce exposure levels and prevent adverse health effects. The results of
individual evaluations may trigger wider studies of similar exposures in other
settings, or may stimulate recommendations for implementation or modification
of health standards. Requests received by the HETA program tend to reflect
emerging occupational problems. More than 8,000 evaluations have been
completed since the inception of the HETA program in 1972 on hazards such as
chemical exposures, indoor air quality, ergonomics and noise-induced hearing
loss.
Noise-induced hearing loss is one of the most prevalent occupational health
hazards facing American workers today. Approximately 30 million people are
exposed to hazardous levels of noise at their work sites and an additional 9
million are at risk from other substances such as solvents and metals. While
noise-induced hearing loss is irreversible, it is preventable and its risk can
be reduced with the application of noise controls and occupational hearing
loss prevention programs.
When evaluating noise during an Health Hazard Evaluation (HHE), staff may
monitor noise exposures, survey worker medical information, conduct worker
audiometric evaluations, assess worker use of hearing loss protection devices,
and evaluate hearing loss prevention policies and standards. NIOSH
researchers present written reports detailing the results of their evaluations
to help companies assess workers exposure to noise, evaluate and plan noise
controls, and develop employee education programs on hearing loss prevention.
This document presents summaries of the HHEs related to noise conducted from
1986-1997. The summaries are organized by industry. In several cases noise
exposure was just one of many exposures that NIOSH researchers investigated at
the work site.
The full reports listed in this document are available from the Hazard
Evaluation and Technical Assistance Branch.
Contact:
The Hazard Evaluation and Technical Assistance Branch (HETAB)
Alice Hamilton Laboratory
4676 Columbia Parkway
Cincinnati, OH 45226
or call:
1-800-35-NIOSH
More information about the Health Hazard Evaluation Program is available on
the web at http://www.cdc.gov/niosh/hhe/.
The PDF version is also available. (12 pages, 75K).
Agriculture, Forestry, and Fishing (SIC 0100-0999)
Assessing Exposure to Noise during Aerial Pesticide Application
HETA 95-0248-2562
March 1996
Purpose:
To investigate worker exposure to noise during aerial pesticide application.
Keywords:
SIC 0721 (Crop Planting, Cultivating, and protecting) aerial dusting and spraying, pesticide exposure, organophosphate, carbamate, pyrethroid, skin exposure, mixer-loader, pilot, noise, personal hearing protection, hearing conservation program, heat stress.
Abstract:
NIOSH researchers conducted a HHE at an aerial pesticide
application firm in Arkansas. Personal noise monitoring was conducted on two
pilots and all three mixer-loaders and spectral noise analyses were conducted
to determine the dominant noise frequencies and to evaluate the flight helmets
for noise attenuation. The noise monitoring showed that both pilots sampled
were exposed TWA sound levels higher than the NIOSH REL and the OSHA PEL for
noise. The TWA noise exposures of the mixer loaders also exceeded the NIOSH
REL, but not the OSHA regulation. Recommendations are made for improving
safety during the use of pesticides and for the implementation of a medical
surveillance program.
Construction (SIC 1500-1799)
Assessing Workers' Exposure to Noise in Bridge Repainting
HETA 91-006-2193
March 1992
Purpose:
To investigate exposure to noise in bridge repainting.
Keywords:
SIC 1622 (Bridge, Tunnel, and Elevated Highway Construction), lead, abrasive blasting, construction, bridge workers.
Abstract:
NIOSH conducted a Health Hazard Evaluation (HHE) to evaluate
workers exposure to noise during repainting of the Brent Spence Bridge, a
double-level highway bridge over the Ohio River in Covington, Kentucky.
Personal exposures to noise, expressed as 8-hour time-weighted averages
(TWAs), ranged from 89.6 decibels on the Aweighted slow weighting network
[dB(A)] to 105.4 dB(A). Most workers surveyed had 8-hr TWA noise exposures
exceeding the NIOSH Recommended Exposure Limit (REL) of 85 dB(A), and the
Occupational Safety and Health Administration (OSHA) permissible exposure
limit (PEL) of 90 dB(A). All workers were provided, and used, hearing
protection devices (earplugs); however, they were not protected by a
comprehensive hearing conservation program. Recommendations for an improved
hearing conservation program are presented in the full report.
Manufacturing (SIC 2000-3999)
Evaluation of Planned Noise Abatement Procedures in Two Sawmill Facilities
HETA 88-030-2109
April 1991
Purpose:
To investigate planned noise abatement procedures in two sawmill facilities.
Keywords:
SIC 2421 (Sawmills and Planing Mills, General), noise exposure, hearing loss, noise control engineering, hearing conservation programs.
Abstract:
In this evaluation, NIOSH assisted a sawmill company in evaluating
the effects of noise abatement procedures planned for its two milling
facilities. Additionally, employee data were gathered on hearing ability,
employment history at the company, and any noise exposure or medical problems
that might affect hearing. Results revealed that 73% of the surveyed job
descriptions in the mills had average noise levels in excess of the NIOSH REL.
The noise controls tested in the mill were found to produce varying amounts of
noise reduction to the workers. The hearing tests revealed that 72.5% of the
employees exhibited some degree of hearing impairment at one or more
audiometric test frequency. NIOSH investigators concluded that a health
hazard exists for the companys employees. It was recommended that a
comprehensive hearing conservation program minimally complying with OSHA
regulations should be implemented in order to protect these employees from
excessive noise exposures in the work place.
Evaluating Noise Controls at a Paper Mill Facility
HETA 86-437-1818
July 1987Purpose:
To investigate the effectiveness of a rotary knife blade enclosure in reducing worker exposure to noise at a paper mill facility.
Keywords:
SIC 2645 (DieCut Paper and Paperboard and Cardboard), noise, paper making industry, paper cutters, enclosures.
Abstract:
NIOSH conducted an evaluation of the noise levels found in the
small paper cutter area of an Ohio paper mill before and after installing an
enclosure over the rotary knife blade. The results of the area noise sampling
showed a noise reduction of 13 dB(A) as a function of the knife blade
enclosure, going from 108 dB(A) prior to installation to 95 dB(A) after
enclosing the blade. However, the personal noise dosimetry results showed
little change from the preenclosure to postenclosure sampling period. This
apparent paradox was partially explained as the result of different operators
and their work practices or different weights of paper. It does, however,
point out the difference between noise exposures to workers and noise levels
being emitted by machinery. A noise hazard was found to exist in the small
cutter area of the paper mill. The potential for excess noise exposure was
reduced by enclosing the rotary knife blade, however eighthour TWA values in
excess of 85 dB(A) were common in the area even after the blade was enclosed.
Recommendations to further reduce the noise hazard and to protect the workers
hearing are provided in the full report.
Noise Exposures at a Specialty Chemical Plant
HETA 86-071-1817
July 1987Purpose:
To investigate worker exposure to noise at a specialty chemical manufacturing plant.
Keywords:
SIC 2842 (Specialty Cleaning, Polishing, and Sanitation Preparations) batch process, methylene chloride, noise, acids, alkaline dust, ventilation, personal protective equipment.
Abstract:
NIOSH conducted a HHE to determine worker exposure to noise at a
specialty chemical manufacturing plant. Fullshift noise exposures ranged from
78 to 88 dB(A) TWA with a mean of 82 dB(A) TWA. The percent of the daily
allowable noise exposure based on the OSHA noise PEL of 90 dB(A) for eight
hours ranged from 19 to 74%. Five workers had fullshift noise exposures at or
above 85 dB(A) TWA, the NIOSH recommended exposure limit. Maximum one minute
average noise levels encountered by workers during the shift ranged from 88 to
113 dB(A). Overall area noise measurements ranged from 84 to 96 dB(A). Noise
levels in the facility represent a risk for potential hearing impairment.
Some areas and equipment generate sufficiently high noise levels (85 dB(A) or
greater) to present an auditory hazard for unprotected workers in the
immediate area. Recommendations addressing a hearing conservation program are
presented in the full report.
Evaluating Noise at a Pipe Fabricating Plant
HETA 88-214-1952
March 1989Purpose:
To investigate noise exposure at a pipe fabricating plant.
Keywords:
SIC 3079 (Pipe Fabrication), extruding, polyvinyl chloride, polyethylene, polystyrene, noise.
Abstract:
NIOSH researchers investigated exposures to hazardous levels of
noise at a pipe fabricating plant in West Virginia. Personal, TWA noise
exposure measurements taken over a three-day period ranged from 80 dB(A) to
104 dB(A). Job categories working in areas with hazardous noise levels
included grinder, line takeoff attendant, and hopper attendant. Workers in
the grinding area used hearing protection; however, workers in the other areas
did not use hearing protection and some were exposed to hazardous noise
levels. On the basis of data obtained during this evaluation, NIOSH
investigators concluded that some workers receive hazardous noise exposures.
Recommendations to correct these occupational health/safety problems are
presented in the full report.
Evaluation of Noise Exposures at a Glass Products Manufacturing Facility
HETA 89-137-2005
January 1990 Purpose:
To investigate worker exposure to noise in a glass products manufacturing facility.
Keywords:
SIC 3231 (Glass Products, Made of Purchased Glass), silica, hydrofluoric acid, sulfuric acid, organic vapors, mineral spirits, pine oil, noise, cumulative trauma disorder, ventilation.
Abstract:
NIOSH conducted an evaluation of employee exposures to noise in a
glass manufacturing facility along with many other occupational exposures.
Noise exposures were assessed by measuring the sound levels in the Furnace,
Decorating, and Mirroring Departments. Personal noise exposures ranged from
79 to 92 dB(A), TWA, in the areas tested. Noise levels in excess of the NIOSH
REL were found in several departments. Based on the data collected during
this evaluation, NIOSH investigators concluded that employees in several
departments at the company were exposed to excessive levels of noise.
Recommendations for implementing hearing conservation programs are included in
the full report.
Noise Exposures and Hearing Loss in Workers Involved in the Manufacture of Roofing Granules
HETA 91-0091-2418
May 1994Purpose:
To investigate noise exposures and hearing loss in roofing granules manufacturing.
Keywords:
SIC 3295 (Minerals and Earths, Ground or Otherwise Treated), silica, noise, hearing conservation.
Abstract:
This investigation was performed in response to a request from the
Oil, Chemical and Atomic Workers union that listed hearing loss as a health
concern in workers involved in the manufacture of roofing granules. Hearing
losses were reportedly documented by company hearing tests, but the union
reported that the manufacturer did not address the losses. NIOSH
investigators performed a walk-through inspection of the plant. Medical
records from both individual employees and the company medical department, and
health survey questionnaires distributed by the local union were reviewed.
Noise dosimeter measurements and area noise levels were made in several areas
of the plant. Personal noise dosimetry revealed that a majority of the
samples were in excess of the NIOSH REL of 85dB(A) for an 8-hour TWA.
Recommendations for reducing exposures to noise are included in full report.
Field Survey at an Oxygen Process Shop to Evaluate Potential Hazards from Air Contaminants, Noise, Heat Stress, and Ergonomic Problems
HETA 92-0230-2471
November 1994Purpose:
To investigate noise exposures in oxygen processing.
Keywords:
SIC 3312 (Steel Works, Blast Furnaces [including coke ovens], and Rolling Mills), air contaminants, metals, sulfur dioxide, noise, hearing aids, heat stress, ergonomics, vibration, lifting.
Abstract:
NIOSH investigators conducted a field survey at an oxygen process
shop to evaluate potential hazards from noise. Employee reports of tinnitus
(ringing in the ears) related to work schedules and long-term hearing problems
suggest that the companys hearing conservation program might not be effective.
The interviewed employees identified the following sources of noise: warning
sirens and horns, scrap dropping into the charge, plates hitting the floor,
furnaces, mixers, discharge of the electric arc, preheaters, heavy equipment
such as grade-alls and cranes, air hammers, and poorly functioning air-conditioning units. The maximum area noise measurements ranged from 80 to 106
dB(A), depending on the area. The findings of this health hazard evaluation
indicate that the shop employees are potentially exposed to dangerous levels
of noise, which may be having a deleterious effect on employee hearing.
Specific recommendations for reducing employee exposure to noise are made in
the full report.
Evaluating Noise Exposures Occurring in the Manufacture of Road Signs
HETA 86-191-1836
February 1987Purpose:
To investigate noise levels in a sign manufacturing shop.
Keywords:
SIC 3499 (Fabricated Metal Products, Not Elsewhere Classified) silk-screening, organic solvents, inks, noise, sign fabrication.
Abstract:
NIOSH investigators evaluated noise exposures from the sign
fabrication process conducted at a sign shop in West Virginia. Personal noise
exposure measurements were taken using a noise dosimeter and a portable sound
level meter with an octave band analyzer. Personal, TWA noise exposures from
the sign fabrication shop did not exceed allowable exposure levels as averaged
over the entire work shift. However, some workers received brief exposures to
sound levels above 115 dB(A) from the operation of the metal saw. NIOSH
investigators concluded that some workers receive potentially hazardous noise
exposures in the sign fabrication shop. Recommendations for prevention of
these problems are presented in the full report.
Evaluating Noise Levels at an Outboard Motor Manufacturing Facility
HETA 93-0498-2409
March 1994Purpose:
To investigate noise in outboard motor manufacturing.
Keywords:
SIC 3519 (Internal Combustion Engines, Not Elsewhere Classified), outboard marine motor manufacturing, noise dosimetry, octave-band analysis, hearing conservation, engineering controls.
Abstract:
Investigators from NIOSH conducted a HHE to evaluate noise levels
at an outboard motor manufacturing facility. A request from the joint
union/management team at the company asked for assistance from NIOSH to help
meet a company noise reduction goal of 82 dB(A). The team felt that a
reduction in plant noise would improve workers ability to communicate, reduce
stress in the work place, and improve product quality while protecting workers
from occupational hearing loss. Personal noise exposure measurements
collected with noise dosimeters on eighteen employees and octave band analyses
of various departments were completed over two days at the facility.
Prominent noise sources included the use of compressed air in several
operations and outboard motor noise generated during the wet and dyno testing
operations. The results of the evaluation revealed that employees in the
machining, assembly, and testing departments were exposed to potentially
harmful noise. A majority of the TWA noise exposure levels exceed the NIOSH
REL for occupational noise. Recommendations for implementing specific
elements of a hearing conservation program as well as suggestions for noise
controls that should help to reduce the noise levels in the facility were
offered in the full report.
Evaluating Worker Exposure to Noise at a Manufacturer of Industrial Centrifugal Equipment
HETA 95-0167-2539
November 1995Purpose:
To investigate exposure to noise in industrial centrifugal manufacturing.
Keywords:
SIC 3559 (Special industry machinery, not elsewhere classified), industrial centrifugal equipment manufacture, noise exposure, noise dosimetry, hearing conservation.
Abstract:
NIOSH received a request from employees and from a United Auto
Workers local at a manufacturer of industrial centrifugal equipment to conduct
a health hazard evaluation at the facility. The concern was worker noise
exposure in the main building, particularly the noise associated with a
recently installed air compressor. In the request, it was pointed out that a
few employees had been identified as having hearing loss at a local hospital.
The employees were concerned that the losses may be occupationally related. A
NIOSH investigator conducted a full-shift noise survey in the main building of
the facility using noise dosimeters. Additional noise measurements were made
with a real-time analyzer to determine the spectral content of specific noisy
operations. Based on the results of the noise data analyses and observations
made during the evaluation, the NIOSH investigator concluded that a health
hazard related to potential hearing loss exists for employees at facility. A
majority of the workers were exposed to time-weighted noise levels in excess
of the NIOSH recommendation, while 35% of the sampled employees exceeded the
OSHA action level that stipulates that a hearing conservation program needs to
be implemented. Hearing conservation program recommendations toward reducing
the noise exposures and preventing further hearing losses were offered in the
report.
Evaluating Employees' Noise Exposures in Conjunction with the Use of Personal Radio Headsets on the Job Site
HETA 90-281-2319
May 1993Purpose:
To investigate noise exposures and personal radio headset usage in an electrical distribution equipment manufacturing facility.
Keywords:
SIC 3613 (Electric Transmission and Distribution Equipment, Switchgear and Switchboard Apparatus), noise, personal radio headsets, hearing conservation programs.
Abstract:
NIOSH received a request for a HHE to evaluate employees
occupational noise exposures in conjunction with the use of personal radio
headsets on the job site. One portion of the request concerned the
applicability of employees using a radio headset over plugged ears in areas
requiring hearing protection. Employee noise exposures measured with noise
dosimeters revealed a median 8 hour TWA noise exposure of 84.6 dB(A). One
full-shift noise sample exceeded 90 dB(A), the OSHA PEL. Because 50% of the
noise exposures equaled or exceeded the recommended limits, investigators
determined that a potential for employee exposure to excessive noise exists.
The company should continue with its hearing conservation program that was in
place at the time of the survey. Also, the potential for excessive noise
produced by personal radio headsets turned to full volume should lead the
company to educate the employees on the hazards associated with the devices.
Specific recommendations are contained in the full report.
Evaluation of Potential Exposures to Noise at an Energy and Automation Plant
HETA 91-305-2267
November 1992Purpose:
To investigate noise exposures in an energy automation plant.
Keywords:
SIC 3621 (Motors and Generators), motor manufacturing, trace metals, noise, welding, brazing, soldering.
Abstract:
A HHE was conducted to evaluate potential exposures to noise at an
energy and automation plant. Employee interviews and an area noise survey
were conducted. The survey identified several areas of the plant where
workers may have been overexposed to noise. A full-shift noise survey was
conducted to document employees personal noise exposures in the welding, punch
press, and machine taping areas. Results of the environmental monitoring
indicate that a health hazard existed for welders and press operators from
overexposures to noise. Recommendations were provided to reduce noise
exposures and improve the hazard communication program.
Evaluating Noise Exposure in an Electronics Manufacturing Plant
HETA 91-021-2144
October 1991Purpose:
To investigate noise exposure in an electronic manufacturing plant.
Keywords:
SIC 3651 (Household Audio and Video Equipment), noise exposure, noise control engineering, hearing conservation programs.
Abstract:
At the request of company management, NIOSH conducted a HHE at an
electronics manufacturing plant to assist the company in determining the
spectral characteristics of worker noise exposures for the purpose of the
reduction of these levels by the company s plant engineering department. Area
noise sampling and worker noise dosimeter measurements were made in several
locations of the facility to determine workers noise exposures during their
work shifts. The results of the noise measurements revealed several areas in
the plant where the workers are exposed to noise levels in excess of 85 dB(A),
but not in excess of 90 dB(A). Because several of the area noise measurements
and the worker s personal noise dosimetry values were in excess of the NIOSH
Recommended Exposure Limit of 85 dB(A), NIOSH investigators conclude that a
potential health hazard exists for the employees. However, because no
employee audiometric records were evaluated in this evaluation, it cannot be
determined if these noise levels have had a deleterious effect on the workers
hearing. It was recommended that the company use the spectral noise data to
devise noise reduction controls in the affected departments. Specific
recommendations were given for the implementation of a comprehensive hearing
conservation program that should be activated until the noise exposures can be
permanently reduced to levels below 85 dB(A).
Evaluating Worker Exposure to Noise at a Plastic Accessories Manufacturing Plant
HETA 87-159-1962
April 1989Purpose:
To investigate worker exposure to noise at a plastic accessories manufacturing plant.
Keywords:
SIC 3751 (Motorcycles), acetone, styrene, noise.
Abstract:
NIOSH conducted an evaluation of workers noise exposures at a
plastic accessories manufacturing plant. Nine employees wore personal noise
dosimeters to assess their noise exposures. A total of twothirds of the full
shift noise exposures were in excess of the NIOSH REL for noise and the OSHA
action level for implementation of a hearing conservation program. Because of
this finding, attempts to implement engineering controls in some of the
noisier operations should be investigated. Measures to reduce noise exposures
and improve workers safety and health are recommended in the full report.
Transportation and Public Utilities (SIC 4000-4971)
Determining Noise Exposure of Postal Employees
HETA 92-056-2223
May 1992
Purpose:
To investigate noise exposure from an automated Small Parcel and Bundle Sorter.
Keywords:
SIC 4311 (United States Postal Service), noise, automated sorting machines, letter carriers.
Abstract:
In response to postal employee concerns, an investigator from NIOSH
conducted noise surveys at a local post office station to document noise
exposures experienced by employees in the letter sorting area which also
houses an automated Small Parcel and Bundle Sorter (SPABS). Personal noise
dosimetry was conducted on letter carriers in the sorting area and on postal
clerks and mail handlers servicing the SPABS. Although no noise levels were
measured that exceed current evaluation criteria for noise exposure and
occupational hearing loss, the letter carriers do perceive that the noise
emitted by the SPABS is stressful and interferes with their work. The noise
from the automated sorting machine measured by the NIOSH investigator is
clearly audible above the ambient noise in the letter sorting area, with the
stop/start warning device being much louder than background noises. The type
of noise emitted by the warning device, measured in the evaluation, meets
several researchers definition of noise as an occupational stressor because
of its unpredictability and lack of controllability. Therefore,
recommendations are made to reduce the noise in the SPABS and letter sorting
areas. However, there are no current evaluation criteria to cite specific
noise levels that must be reached in order to eliminate the non-auditory
effects of the noise exposure.
Evaluating Landfill Employee Exposure to Noise
HETA 93-0696-2395
March 1994Purpose:
In February 1993, NIOSH conducted a HHE at an Ohio landfill
facility to determine if employee exposures to noise represented a health
hazard. Employees were using hearing protection devices to guard against the
hazards of occupational noise exposure. Noise dosimetry was conducted over
two days on three heavy equipment operators, three mechanics, and a laborer.
The results of noise dosimetry indicate that exposure to noise exceeded the
PEL of 90 dB(A) for an 8 hour TWA. Recommendations are included in this
report to develop a comprehensive hearing conservation program and gives
suggestions for engineering controls to reduce worker exposure to noise.
Evaluation of Noise Levels at a Hydroelectric Power Plant
HETA 92-0243-2377
January 1994Purpose:
To investigate noise exposures in a hydroelectric power plant.
Keywords:
SIC 4910 (Electric services), noise, audiometric testing, infrasound, hydroelectric power.
Abstract:
NIOSH investigators conducted a HHE at an Arkansas hydroelectric
power plant in response to employees concerns about excessive noise levels in
the power plant resulting from the generation of electricity. Personal noise
exposure measurements were made on all of the electricians and mechanics at
work on the days of the surveys with noise dosimeters set to measure noise
according to Department of the Army noise regulations. Spot measurements of
infrasound (sound below the sonic range of human hearing) and simple
measurements of structural vibration were also made during the first site
visit. All of the mechanics and electricians who worked in the power plant
had noise exposures that exceeded the U.S. Army Corps of Engineers safety and
health requirements. However, worker compliance with the wearing of hearing
protective devices while working was observed to be good. Deficiencies were
discovered in the audiometric testing program used at the power plant upon
review of their records.
Wholesale trade (SIC 5000-5199)
Potentially Hazardous Noise in a Cosmetics and Drug Distribution Warehouse
HETA 91-194-2153
October 1991
Purpose:
To investigate noise exposure in a cosmetics and drug distribution warehouse.
Keywords:
SIC 5122 (Drug Proprietaries, Drug Sundries), noise, warehousing.
Abstract:
An investigation was conducted at a drug and cosmetics distribution
warehouse to evaluate potentially hazardous noise in the workplace. During
the investigation, personal noise dosimetry was performed, along with octave
band area noise measurements at various locations throughout the facility.
Analysis of the results of the personal and area noise measurements indicated
that the measured values in the shipping area of the facility approach the
NIOSH REL and OSHA action level (AL) of 85 dB(A) for an 8-hour TWA. These
noise results reveal that no noise hazard exists at the drug company.
However, noise levels in the shipping area are only slightly below the NIOSH
REL and OSHA AL. Therefore, recommendations are made to further reduce
employee exposures to noise using engineering and administrative controls.
Services (SIC 7000-8999)
Evaluating Noise Exposure in a Biomedical Laboratory
HETA 91-287-2228
June 1992
Purpose:
To investigate noise exposure in a biomedical lab.
Keywords:
SIC 8734 (Testing Laboratories), biosafety, agricultural, microbiological and biomedical laboratories, noise.
Abstract:
This HHE was performed in response to a confidential employee
request concerning microbiological safety in a biomedical laboratory. In
addition, once the HHE was in progress, lab management requested an evaluation
of noise exposures in the necropsy suite, in the electron microscopy lab, and
in a veterinarian s office. NIOSH investigators administered a questionnaire
to employees, performed industrial hygiene measurements during the operation
of laboratory apparatus, evaluated selected laboratory hoods with a thermo
anemometer and smoke tubes, and measured noise in the specified areas. The
results showed that the noise levels in these areas did not approach those
associated with the development of noise-induced hearing loss.
Recommendations are made for further reducing the amount of noise to which
workers are exposed.
Public Administration (SIC 9000-9721)
Evaluating Risk of Noise Induced Hearing Loss for Fire Fighters in a Metropolitan Area
HETA 88-0290-2460
September 1994
Purpose:
To investigate noise exposure in fire fighters.
Keywords:
SIC 9224 (Fire Departments, including volunteer), noise exposure, noise dosimetry, fire apparatus, hearing loss, hearing conservation.
Abstract:
A HHE was conducted to evaluate noise exposure levels and hearing
loss for fire fighters in a metropolitan area. Full-shift personal noise
measurements and audiometric testing of fire fighters were done in the
department. The noise dosimeter surveys revealed that average noise exposures
were generally less than the NIOSH recommended exposure limits, but there were
brief occurrences of noise levels greatly exceeding the exposure limits.
These high exposures were usually associated with emergency response runs in
the fire vehicles. A statistically significant relationship was found between
length of time spent as a fire fighter and hearing loss. Based on the results
of the audiometric data analyses, the NIOSH investigator concluded that a
health hazard exists for fire fighters and recommended steps to the fire
department to reduce the noise exposures to the fire fighters and help prevent
further hearing losses.
Evaluating Risk of Noise Induced Hearing Loss for Fire Fighters
HETA 89-0026-2495
March 1995Purpose:
To investigate noise exposure and hearing loss in fire fighters.
Keywords:
SIC 9224 (Fire Departments, including volunteer), noise exposure, noise dosimetry, fire apparatus, hearing loss, hearing conservation.
Abstract:
A health hazard evaluation was completed by testing noise exposure
levels emitted by fire emergency vehicles, noise exposure at fire stations,
and hearing loss for fire fighters. The noise surveys revealed that while the
24-hour cumulative noise doses were generally less than the NIOSH recommended
exposure limits, there were brief occurrences of noise levels greatly
exceeding the exposure limits. These high exposures were usually associated
with emergency response runs in the fire vehicles. The audiometric data
showed a decline in hearing ability in the high frequency sound region, while
at the same time, a significant improvement in hearing at the low
audiometric test frequencies was discovered. These data suggest that, in
spite of the fire fighters improved ability to take a hearing test, there was
still a significant loss of hearing in the noise sensitive region. Based on
the results of the audiometric data analyses, the NIOSH investigator concluded
that a health hazard exists for fire fighters and recommended steps to the
department to reduce the noise exposures to the fire fighters and help prevent
further hearing losses.
Evaluating Police Officers' Exposures to Noise Generated by Gun Firing Exercises
HETA 92-0034-2356
October 1993Purpose:
To investigate noise exposures during gun firing exercises.
Keywords:
SIC 9221 (Police Protection), lead, firing range, noise, ventilation.
Abstract:
NIOSH investigators conducted environmental monitoring of police
officer firing exercises to assess potential occupational exposures to
hazardous noise levels generated at the facility during the hand gun firing
exercises. Peak noise measurements ranged from 157 to 160 dB(A) when officers
were firing their weapons on the indoor range. The hearing protection devices
used by officers are adequate protection when they are properly maintained and
replaced when necessary. Recommendations are provided in the report about
periodic maintenance and replacement for the hearing protection devices.
Evaluate of Noise and Hearing Loss in Fire Fighters
HETA 86-138-2017
February 1990Purpose:
To investigate noise exposures and hearing loss in fire fighters assigned to airports.
Keywords:
SIC 9224 (Fire departments, including volunteer), noise exposure, hearing loss, hearing conservation.
Abstract:
NIOSH conducted noise surveys and audiometric examinations of fire
fighters in a metropolitan area, some of whom were assigned to two fire
stations serving a nearby airport. There was concern that these fire fighters
were at greater risk of accruing hearing loss because of the addition of
aircraft noise to their occupational noise exposures. The noise dosimetry
results revealed timeweighted averages that ranged from 60 to 82 dB(A).
However, the levels encountered during code three responses (warning lights,
sirens, and air horns) reached 109 dB(A) for a oneminute time period. The
audiometric results showed that the average fire fighter exhibited a
characteristic noiseinduced permanent threshold shift. This hearing loss was
statistically related to the amount of time that the fire fighter had been on
the job, with decreasing hearing ability as a function of years of service.
NIOSH investigators conclude that a health hazard exists for these fire
fighters. A comprehensive hearing conservation program should be implemented
in order to reduce the growth of hearing loss for fire fighters. Specific
recommendations are presented in the full report.
Evaluation of Noise Exposure for Two Offices
HETA 91-0308-2376
January 1994Purpose:
To investigate excessive noise in an office environment.
Keywords:
SIC 9311 (Public Finance, Taxation, and Monetary Policy), indoor environmental quality, ventilation, medical questionnaire, office noise, IEQ, GSA.
Abstract:
Investigators from NIOSH conducted a health hazard evaluation for
several offices in an office building in Michigan. Noise conditions in the
office setting were evaluated for their effects on speech intelligibility,
telephone usage, and work interruption rather than on the risk of hearing
damage. NIOSH investigators examined noise levels and determined that the
office environments are suited for only fair to moderate listening conditions.
Recommendations that address communication concerns are offered in the report.
Evaluation of an Air Traffic Approach Control Tower
HETA 96-0184-2663
November 1997Purpose:
To investigate the noise exposure of workers in an air traffic approach control tower.
Keywords:
SIC 9621 (Regulation and Administration of Transportation Programs), air traffic control operations-government, noise, radio headsets, compression circuits, noise-limiting circuits, audiometric testing, hearing conservation program.
Abstract:
In this evaluation, NIOSH visited the airfield to measure noise
levels from the communication systems used by the air traffic control (ATC)
specialists while a noise compression using was inserted into the
communication line, as well as when the unit was removed and unattenuated
signals were allowed to reach the headset receiver. Also, ambient background
noise measurements were made in the controllers work area. Finally,
audiometric test results from the ATC specialists and a copy of the
occupational injury and illness log were reviewed. Analysis of the headset
receiver and the compression unit showed the controllers could be exposed to
equivalent free field noise levels up to 104 dB(A), but that the compression
units functionally reduced the exposure to a safe level. Analysis of the
audiometric records did not reveal any systematic occupational hearing loss in
the population of controllers. Researchers found deficiencies in the manner
in which the compression unit was used and in the hearing tests given to the
controllers. There was a moderately high level of background noise in the
work area that could possibly interfere with speech intelligibility.
Recommendations to alleviate these deficiencies are given in the last section
of this report.