Hearing conservation program
Encyclopedia
Hearing conservation programs are designed to prevent noise induced hearing loss
. A written hearing conservation program is required by the Occupational Safety and Health Administration
(OSHA) “whenever employee noise exposures equal or exceed an 8-hour time-weighted average sound level (TWA) of 85 decibel
s measured on the A scale (slow response) or, equivalently, a dose of fifty percent.” This 8-hour time-weighted average is known as an exposure action value
. While the Mine Safety and Health Administration
(MSHA) also requires a hearing conservation program, MSHA does not require a written hearing conservation program. MSHA’s hearing conservation program requirement can be found in 30 CFR § 62.150, and requires has almost the same exact requirements as the OSHA hearing conservation program requirements. Therefore, only the OSHA standard 29 CFR 1910.95 will be discussed in detail.
(SLM). There are three types of sound level meters. Type 0 is precision instrument normally used in laboratories. A type 1 is for precision measurements taken in the field. Type 2 sound level meters are less precise than type 1 and are often used to take all-purpose sound level measurements. Noise monitoring is generally completed using a noise dosimeter
that integrates “all continuous, intermittent and impulsive sound levels” to determine a person’s noise exposure level.
Surveys must be repeated when there are significant changes in machinery and/or processes that would affect the noise level.
and therefore are normally more protective. However, it is not always feasible to use administrative and engineering controls as the only ways to prevent noise over-exposure. The key is to maintain an 8-hour time-weighted average of less than 85 dBA so that personal protective equipment is not required. On October 19, 2010, the US Department of Labour proposed that the term "feasible" be interpreted as that which is capable of being done, thus enhancing OSHA's ability to enforce this aspect of the standard.
so that the proper amount of noise protection is worn. OSHA requires that hpd be given free of charge.
-Premolded earplugs do not require the plug to be formed before it is inserted into the ear. This prevents the plugs from becoming soiled before insertion.
-Formable earplugs are made of a variety of substances. However, all each substance shares the common feature of being able to be shaped by the user prior to insertion. One drawback of this is the obvious need for the user to have clean hands while shaping the earplug. They do have the advantage of forming to the users ear, while many premolded earplugs do not accomplish this very well.
-Custom molded ear plugs are unique for each person, since they are cast from each user’s own ear canals. Therefore, they provide a personalized fit for each individual.
-Semi-inserts are generally a soft earplug on the end of band. The band aides in maintaining the earplug in position. They are often useful since they can be quickly removed and inserted.
to help reduce noise exposures. However, earmuffs are not commonly worn by people who have sideburns or glasses, who find earmuffs to be uncomfortable.
(EPA) requires that all hearing protection devices be labeled with their associated noise reduction rating (NRR). The NRR provides the estimated attenuation of the hearing protection device. However, it has been found that the “labeled manufacturers' noise reduction ratings (NRRs) substantially overestimated the actual field attenuation performance.” To determine the amount of noise reduction afforded by a hearing protection device, OSHA recommends that 7 db be subtracted from the NRR. The NRR is generally given in a C-weighted format, so to obtain the A-weighted reduction, one must subtract 7 db. OSHA also recommends a 50% safety factor, therefore the final OSHA recommended reduction would be (NRR-7)/2.
is a very important part of a hearing conservation program. Audiometric testing allows for the identification of those that have lost significant hearing. Additionally, the testing allows for the identification of those who are in process of losing their hearing. Audiometric testing is most important in identifying those who have permanent hearing loss. This is called noise-induced permanent threshold shift (NIPTS)
Noise exposure measurement records must be maintained for at least 2 years. Audiometric test records must be retained for the duration of the affected employee’s employment. Additionally, employees, former employees, representatives designated by the individual employee and the Assistant Secretary all must have access to these records.
(NIOSH) has created a checklist to help evaluate the effectiveness of a hearing conservation program. It can be found on their website. NIOSH recommends that fewer than 5% of exposed employees should have a 15 dB Significant Threshold Shift in the same ear and same frequency.
The National Institute for Occupational Safety and Health is pushing a higher emphasis on a hearing loss prevention program rather than a hearing conservation program. While this change may seem superfluous, it is important to note the advancement. Prevention implies a response by the workplace caused by initial signs of employee hearing loss rather than instilling a new set of policies (such as “buy quiet”) and thinking (such as hearing protection training and education) to decrease the possibility of occupational hearing loss from happening in the first place.
The Buy Quiet policy is an easy way to progress towards a safer work environment. Many traditionally noisy tools and machines are now being redesigned in order to manufacture quieter running equipment, so a “buy quiet” purchase policy should not require new engineering solutions in most cases. As a part of the “buy quiet” campaign, the New York City Department of Environmental Protection released a products and vendor guidance sheet in order to assist contractors for achieving compliance with the New York City Noise Regulations.
In order to make these plans effective, employees and administration need to be educated in occupational noise-induced hearing loss prevention. It is also necessary to identify and examine sources of noise first before being able to control the damage it may cause to hearing. For example, the National Institute for Occupational Safety and Health has conducted a study and created a database on handheld power tools for the sound power levels they expose their operators to. This Power Tools Database
allows contractors in a trade-skill profession to monitor their exposure limits and allow them preparation to prevent permanent hearing damage.
Noise induced hearing loss
Noise-induced hearing loss is an increasingly prevalent disorder that results from exposure to high-intensity sound, especially over a long period of time.-Description:...
. A written hearing conservation program is required by the Occupational Safety and Health Administration
Occupational Safety and Health Administration
The United States Occupational Safety and Health Administration is an agency of the United States Department of Labor. It was created by Congress of the United States under the Occupational Safety and Health Act, signed by President Richard M. Nixon, on December 29, 1970...
(OSHA) “whenever employee noise exposures equal or exceed an 8-hour time-weighted average sound level (TWA) of 85 decibel
Decibel
The decibel is a logarithmic unit that indicates the ratio of a physical quantity relative to a specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power quantities...
s measured on the A scale (slow response) or, equivalently, a dose of fifty percent.” This 8-hour time-weighted average is known as an exposure action value
Exposure action value
An Exposure Action Value or Action Value is a limit set on occupational exposure to noise where beyond those values, employers must take steps to monitor the exposure levels. These levels are measured in decibels. The American Occupational Safety and Health Administration set the EAV to...
. While the Mine Safety and Health Administration
Mine Safety and Health Administration
The Mine Safety and Health Administration is an agency of the United States Department of Labor which administers the provisions of the Federal Mine Safety and Health Act of 1977 to enforce compliance with mandatory safety and health standards as a means to eliminate fatal accidents, to reduce...
(MSHA) also requires a hearing conservation program, MSHA does not require a written hearing conservation program. MSHA’s hearing conservation program requirement can be found in 30 CFR § 62.150, and requires has almost the same exact requirements as the OSHA hearing conservation program requirements. Therefore, only the OSHA standard 29 CFR 1910.95 will be discussed in detail.
Program requirements
The OSHA standard contains a series of program requirements.- Engineering Controls: 29 CFR 1910.95(b)(1) requires that “feasible administrative or engineering controls shall be utilized. If such controls fail to reduce sound levels…personal protective equipment shall be provided and used to reduce sound levels…”
- Monitoring: 29 CFR 1910.95(d) requires that monitoring be conducted when “any employee’s exposure may equal or exceed an 8-hour time-weighted average of 85 decibels.
- Testing: 29 CFR 1910.95(g) requires an “audiometric testing program” for “all employees whose exposures equal or exceed an 8-hour time-weighted average of 85 decibels”.
- Hearing Protectors: 29 CFR 1910.95(i) states that “employers shall make hearing protectors available to all employees exposed to an 8-hour time-weighted average of 85 decibels or greater at no cost to the employees”
- Training: 29 CFR 1910.95(k) mandates an annual “training program” for “all employees who are exposed to noise at or above an 8-hour time-weighted average of 85 decibels…” and mandates certain aspects of the training that must be included. This includes the effects of noise on hearing; purpose, advantages, disadvantages, and attenuation of different types of hearing protectors; purpose audiometric testing.
- Record Keeping: 29 CFR 1910.95(m) states that employers “shall maintain an accurate record of all employee exposure measurements…”
Sound survey
A sound survey is often completed to determine areas of potential high noise exposure. This type of survey is normally completed using a sound level meterSound level meter
Sound level meters measure sound pressure level and are commonly used in noise pollution studies for the quantification of almost any noise, but especially for industrial, environmental and aircraft noise. However, the reading given by a sound level meter does not correlate well to...
(SLM). There are three types of sound level meters. Type 0 is precision instrument normally used in laboratories. A type 1 is for precision measurements taken in the field. Type 2 sound level meters are less precise than type 1 and are often used to take all-purpose sound level measurements. Noise monitoring is generally completed using a noise dosimeter
Noise dosimeter
A noise dosimeter or noise dosemeter is a specialized sound level meter intended specifically to measure the noise exposure of a person integrated over a period of time; usually to comply with Health and Safety regulations such as the Occupational Safety and Health or EU Directive 2003/10/EC.-...
that integrates “all continuous, intermittent and impulsive sound levels” to determine a person’s noise exposure level.
Surveys must be repeated when there are significant changes in machinery and/or processes that would affect the noise level.
Administrative and engineering controls
Administrative and engineering controls are the preferred method to prevent noise exposure. Normally, administrative and engineering controls do not require personal protective equipmentPersonal protective equipment
Personal protective equipment refers to protective clothing, helmets, goggles, or other garment or equipment designed to protect the wearer's body from injury by blunt impacts, electrical hazards, heat, chemicals, and infection, for job-related occupational safety and health purposes, and in...
and therefore are normally more protective. However, it is not always feasible to use administrative and engineering controls as the only ways to prevent noise over-exposure. The key is to maintain an 8-hour time-weighted average of less than 85 dBA so that personal protective equipment is not required. On October 19, 2010, the US Department of Labour proposed that the term "feasible" be interpreted as that which is capable of being done, thus enhancing OSHA's ability to enforce this aspect of the standard.
Hearing protection device
If engineering controls fail to maintain an 8-hour time-weighted average below 85 dBA, then a hearing protection device (hpd) is required. There are two general types of hpd’s: earplugs and ear muffs. Each one has its own benefits and drawbacks. The selection of the proper hpd to be worn is commonly done by an industrial hygienistOccupational hygiene
Occupational hygiene is generally defined as the art and science dedicated to the anticipation, recognition, evaluation, communication and control of environmental stressors in, or arising from, the workplace that may result in injury, illness, impairment, or affect the well being of workers and...
so that the proper amount of noise protection is worn. OSHA requires that hpd be given free of charge.
Earplugs
There are four general classes of earplugs. These include: premolded, formable, custom molded and semi-insert.-Premolded earplugs do not require the plug to be formed before it is inserted into the ear. This prevents the plugs from becoming soiled before insertion.
-Formable earplugs are made of a variety of substances. However, all each substance shares the common feature of being able to be shaped by the user prior to insertion. One drawback of this is the obvious need for the user to have clean hands while shaping the earplug. They do have the advantage of forming to the users ear, while many premolded earplugs do not accomplish this very well.
-Custom molded ear plugs are unique for each person, since they are cast from each user’s own ear canals. Therefore, they provide a personalized fit for each individual.
-Semi-inserts are generally a soft earplug on the end of band. The band aides in maintaining the earplug in position. They are often useful since they can be quickly removed and inserted.
Earmuffs
Earmuffs are another type of hpd. The main difference between earmuffs and earplugs, is that earmuffs are not inserted inside the ear canal. Instead the muffs create a seal around the outside of the ear to prevent noise from reaching the inner ear. Earmuffs are easy to wear and often provide a more consistent fit than an earplug. There are earmuffs available that use the principle of active noise controlActive noise control
Active noise control is a method for reducing unwanted sound.- Explanation :...
to help reduce noise exposures. However, earmuffs are not commonly worn by people who have sideburns or glasses, who find earmuffs to be uncomfortable.
Noise reduction ratings
The United States Environmental Protection AgencyUnited States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
(EPA) requires that all hearing protection devices be labeled with their associated noise reduction rating (NRR). The NRR provides the estimated attenuation of the hearing protection device. However, it has been found that the “labeled manufacturers' noise reduction ratings (NRRs) substantially overestimated the actual field attenuation performance.” To determine the amount of noise reduction afforded by a hearing protection device, OSHA recommends that 7 db be subtracted from the NRR. The NRR is generally given in a C-weighted format, so to obtain the A-weighted reduction, one must subtract 7 db. OSHA also recommends a 50% safety factor, therefore the final OSHA recommended reduction would be (NRR-7)/2.
Audiometric testing program
Audiometric testingAudiometry
Audiometry is the testing of hearing ability, involving thresholds and differing frequencies. Typically, audiometric tests determine a subject's hearing levels with the help of an audiometer, but may also measure ability to discriminate between different sound intensities, recognize pitch, or...
is a very important part of a hearing conservation program. Audiometric testing allows for the identification of those that have lost significant hearing. Additionally, the testing allows for the identification of those who are in process of losing their hearing. Audiometric testing is most important in identifying those who have permanent hearing loss. This is called noise-induced permanent threshold shift (NIPTS)
Employee training and education
Proper training and education of those exposed to noise is the key to preventing noise-induced hearing loss. If employees are properly trained on how to follow a hearing conservation program, then the risk of noise-induced hearing loss is reduced. OSHA requires said training to be completed on an annual basis. Proper training is imperative since “even with a very modest amount of instruction attenuation performance can be significantly improved.”Record keeping
OSHA requires that records of exposure measurements and audiometric tests be maintained. Records are also required to have the following:- name and job classification
- date of the audiogram
- examiner’s name
- calibration date
- employee’s most recent noise exposure assessment
- background sound pressure levels in audiometric test booths.
Noise exposure measurement records must be maintained for at least 2 years. Audiometric test records must be retained for the duration of the affected employee’s employment. Additionally, employees, former employees, representatives designated by the individual employee and the Assistant Secretary all must have access to these records.
Program evaluation
Proper program evaluation is important in maintaining the health of hearing conservation program. The National Institute for Occupational Safety and HealthNational Institute for Occupational Safety and Health
The National Institute for Occupational Safety and Health is the United States’ federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the Centers for Disease Control and Prevention within the U.S...
(NIOSH) has created a checklist to help evaluate the effectiveness of a hearing conservation program. It can be found on their website. NIOSH recommends that fewer than 5% of exposed employees should have a 15 dB Significant Threshold Shift in the same ear and same frequency.
The National Institute for Occupational Safety and Health is pushing a higher emphasis on a hearing loss prevention program rather than a hearing conservation program. While this change may seem superfluous, it is important to note the advancement. Prevention implies a response by the workplace caused by initial signs of employee hearing loss rather than instilling a new set of policies (such as “buy quiet”) and thinking (such as hearing protection training and education) to decrease the possibility of occupational hearing loss from happening in the first place.
The Buy Quiet policy is an easy way to progress towards a safer work environment. Many traditionally noisy tools and machines are now being redesigned in order to manufacture quieter running equipment, so a “buy quiet” purchase policy should not require new engineering solutions in most cases. As a part of the “buy quiet” campaign, the New York City Department of Environmental Protection released a products and vendor guidance sheet in order to assist contractors for achieving compliance with the New York City Noise Regulations.
In order to make these plans effective, employees and administration need to be educated in occupational noise-induced hearing loss prevention. It is also necessary to identify and examine sources of noise first before being able to control the damage it may cause to hearing. For example, the National Institute for Occupational Safety and Health has conducted a study and created a database on handheld power tools for the sound power levels they expose their operators to. This Power Tools Database
NIOSH Power Tools Database
The NIOSH Power Tools Database contains sound power levels, sound pressure levels, and vibrations data for a variety of common power tools that have been tested by researchers. Data are collected for both the unloaded and loaded use of power tools...
allows contractors in a trade-skill profession to monitor their exposure limits and allow them preparation to prevent permanent hearing damage.
See also
- Hearing impairmentHearing impairment-Definition:Deafness is the inability for the ear to interpret certain or all frequencies of sound.-Environmental Situations:Deafness can be caused by environmental situations such as noise, trauma, or other ear defections...
- AudiometryAudiometryAudiometry is the testing of hearing ability, involving thresholds and differing frequencies. Typically, audiometric tests determine a subject's hearing levels with the help of an audiometer, but may also measure ability to discriminate between different sound intensities, recognize pitch, or...
- Exposure Action ValueExposure action valueAn Exposure Action Value or Action Value is a limit set on occupational exposure to noise where beyond those values, employers must take steps to monitor the exposure levels. These levels are measured in decibels. The American Occupational Safety and Health Administration set the EAV to...
- Noise-induced hearing loss
- Safe-In-Sound Award
- List of occupational health and safety awards