The Audiologist's Role in Occupational Hearing Conservation and Hearing Loss Prevention Programs

Technical Report

Working Group on Occupational and Nonoccupational Hearing Conservation


About this Document

This technical report and accompanying position statement were updated from existing policy documents, “The Audiologist's Role in Occupation Hearing Conservation” (LC7-84), 1985 and “The Audiologist's Role in Occupational and Environmental Hearing Conservation,” 1996. The document was developed by the Working Group on Occupational and Nonoccupational Hearing Conservation and was adopted by the ASHA Legislative Council in March 2003. Members of the Working Group on Occupational and Nonoccupational Hearing Conservation included George R. Cook, Jr., Rena H. Glaser, Henry J. Ilecki (ex officio), Gail Linn (ex officio), Mary M. McDaniel, Maurice H. Miller (coordinating committee member), Julia Doswell Royster (chair), Theresa Schulz, and Myrna M. Stephens. Richard Nodar and Susan J. Brannen, ASHA vice presidents for professional practices in audiology, served as monitoring vice presidents.



Introduction

This report expresses ASHA's position regarding audiologists' participation in hearing conservation, both occupational and nonoccupational. For the purpose of this discussion, occupational hearing conservation is defined as the prevention of significant, permanent hearing loss resulting from on-the-job exposure to ototoxic or ototraumatic agents (of which noise is the most common) in workers (employees and military personnel). Nonoccupational hearing conservation refers to the prevention of significant, permanent hearing loss resulting from off-the-job exposure to ototraumatic agents (most commonly noise) in persons of all ages.

This report has been formulated to offer guidance to audiologists, related professionals, and consumers of occupational and nonoccupational hearing conservation services in the following areas:

  • Preparation of the audiologist to provide hearing conservation services;

  • Role of the audiologist on the interdisciplinary team in hearing conservation;

  • Components of service delivery in hearing conservation; and

  • Professional ethics related to service delivery in hearing conservation.

Noise-induced hearing loss (NIHL) is the most common occupational disease and the second most self-reported occupational illness or injury, according to the National Institute for Occupational Safety and Health (NIOSH, 1998b). Approximately 30 million American workers are sometimes exposed on the job to sound levels exceeding 75–80 dBA (decibels sound pressure level measured using the A frequency-weighting network on a sound level meter), but not all of these persons have daily equivalent noise exposures constituting a hazard to hearing. An additional 9 million are at risk for hearing loss from exposure to other agents such as solvents and heavy metals, which may act either independently of noise to cause hearing damage, or synergistically with simultaneous noise exposures (NIOSH, 1998b). According to the National Institute for Deafness and Other Communicative Disorders (NIDCD), 20 million workers have regular workplace noise exposures to daily equivalent sound levels of 75 dB or more, which is the lower limit of exposure considered capable of causing any measurable noise-induced hearing damage over a lifetime. Estimates of the number of persons exposed to daily equivalent sound levels of 85 dBA or higher (deemed hazardous) vary from 5 million (NIOSH, 1998a) to 9 million (Bruce & Simpson, 1981).

Audiologists have been involved in noise-related issues since the inception of the profession (see Appendix 1, Historical Perspective), and they continue to be active today. According to the 1994 ASHA Omnibus Survey, 45% of audiologists provided some OHCP services as part of their job (ASHA, 1994). This percentage increased to more than 56% in the 1999 Omnibus Survey (ASHA, 1999). The services most commonly provided by audiologists were audiologic follow-up evaluations in response to HCPs monitoring audiometry, fitting and dispensing of hearing protection devices, and review of monitoring audiograms. Fewer audiologists surveyed reported that they supervise OHCPs or serve as consultants to industry, and even fewer are involved in noise measurement, training of occupational hearing conservationists (OHCs) or other technicians, or HCP audits and program evaluations. Although the percentage of all audiologists whose practices focus on occupational hearing conservation is small, audiologists play a leading role in the hearing conservation field, and the large majority of OHC training course directors certified by the Council for Accreditation in Occupational Hearing Conservation (CAOHC) are audiologists.

The delivery of quality hearing conservation services by audiologists involved in these activities depends on proper academic preparation, professional experience, and adherence to standards of professional conduct. Audiologists for whom hearing conservation is a secondary or minor focus must ensure that they have mastered the details concerning NIHL and its prevention, as well as the regulations that apply to occupational noise exposures, before offering services in support of HCPs. Those audiologists who have made the effort to gain expertise in noise-related technical information (plus other ototraumatic hazards) can take a valuable leadership role in interdisciplinary hearing conservation teams. The audiologist brings special knowledge about hearing and communication to the OHCP team.

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Preparing the Audiologist to Provide Occupational Hearing Conservation Services

Core Academic Preparation. Graduate education programs in audiology that are accredited by ASHA's Council on Academic Accreditation (known prior to January 1996 as the Educational Standards Board) offer core curricula that include the following areas (ASHA, 1997):

  1. Auditory disorders, such as (a) pathologies of the auditory system and (b) assessment of auditory disorders and their effect on communication;

  2. Habilitative/rehabilitative procedures, such as (a) selection and use of appropriate amplification instrumentation for the hearing impaired and (b) management procedures for speech and language habilitation and/or rehabilitation of the hearing impaired (that may include manual communication);

  3. Conservation of hearing, such as (a) environmental noise control in the testing room and (b) identification audiometry (school, military, industry); and

  4. Instrumentation, such as (a) electronics, (b) calibration techniques, and (c) characteristics of amplifying systems.

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Audiologist's Role on an Interdisciplinary Team in Occupational Hearing Conservation

Audiologists must be qualified by education and experience if they are to assume a leadership role in the development and implementation of OHCPs. In this role, they should cooperate with members of other disciplines and coordinate activities to enhance the proper development and operation of effective programs. The other professional disciplines may include acoustical engineering, industrial engineering, otolaryngology, occupational medicine, safety engineering, occupational health nursing, industrial hygiene, human resource management, and information management, as well as technicians (including OHCs) with specific OHCP duties. The extent of involvement of each discipline will be determined by the employers' needs, resources, and organizational structure. Regardless of which professionals may serve as consultants to the OHCP, the everyday leadership of an on-site key individual is critical to the success of the program (J. D. Royster & Royster, 1990; Stewart, 2000).

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Components of Service Delivery in Occupational Hearing Conservation

A model HCP includes seven general components:

  1. Noise exposure assessment;

  2. Engineering noise controls and administrative controls of noise exposure (the approaches preferred instead of the use of personal HPDs to reduce employees' noise exposures);

  3. Personal hearing protection, including its selection, user fitting and training, and supervised use;

  4. Audiometric testing, audiogram review, and follow-up steps, including referral as needed;

  5. Education and motivation of management and workers;

  6. Recordkeeping; and

  7. Analysis of program effectiveness.

The audiologist participates in each program component to a greater or lesser extent depending on his or her education and skills and the particular employer's needs and resources. The audiologist can advise management on many operational aspects of the hearing conservation program, including management responsibilities and liabilities under federal, state, and local occupational health and safety regulations and Workers' Compensation statutes. The audiologist can recommend the most successful and cost-effective means of implementing each component of the program, considering the advantages and disadvantages of developing in-house resources versus contracting with external service providers (J. D. Royster, 2000; Stewart, 2000;).

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Professional Ethics Related to Service Delivery in Occupational Hearing Conservation

Preservation of the highest standards of integrity and ethical principles is vital to the responsible discharge of obligations in the profession of audiology. The ASHA Code of Ethics (1994) sets forth the fundamental principles and rules considered essential to this purpose. It contains several principles and rules that are especially relevant to the provision of hearing conservation services.

Principle of Ethics I states that “individuals shall honor their responsibility to hold paramount the welfare of persons they serve professionally.” The audiologist providing services under contract or on a fee-for-service basis must attempt to the best of his or her ability to serve the welfare of both the employer and the noise-exposed individual. This principle relates specifically to the area of audiometric testing, audiogram review, and medical/audiologic referral. Information regarding auditory status and related matters should be made available to the exposed individual.

Principle of Ethics I, Rule E, states that “individuals shall evaluate the effectiveness of services rendered and products dispensed and shall provide services or dispense products only when benefit can reasonably be expected.” In developing referral procedures, the audiologist should avoid actual or potential conflict of interest. The referred worker should be given a choice of referral specialists or facilities. If the audiologist is under contract to provide services on behalf of the company, referrals to the audiologist's private practice may not be appropriate and should be avoided. Referrals should be made to audiologists who hold the CCC-A, are licensed in states that require licensure, and are experienced and competent in the area of occupational hearing conservation. The audiologist providing or supervising hearing conservation services must develop or use currently available methods of measuring the effectiveness of these services and products. Products dispensed (such as HPDs) should be appropriate for the workplace in which they will be used. The audiologist should not derive financial or other benefit from the recommendation of one product or piece of equipment over another.

Principle of Ethics II states that “individuals shall honor their responsibility to achieve and maintain the highest level of professional competence.” An audiologist intending to provide hearing conservation services must be properly prepared to offer these services through either preservice and/or in-service training and experiential activities.

Principle of Ethics II, Rule D, states that “individuals shall delegate the provision of clinical services only to persons who are certified or to persons in the education or certification process who are appropriately supervised. The provision of support services may be delegated to persons who are neither certified nor in the certification process only when a certificate holder provides appropriate supervision.” It is the responsibility of audiologists who supervise OHCs and other technicians in hearing testing, personal hearing protection fitting, and recordkeeping to maintain adequate supervision of such persons to ensure their continued competency.

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Summary

Exposure to noise poses a continuing hazard to the hearing health of millions of individuals. The development and implementation of effective OHCPs and other HLPPs can and will prevent needless cases of hearing loss. Audiologists are especially qualified to exercise a leadership role in the development and implementation of HCPs. This position statement has addressed issues germane to the participation of audiologists in HCPs, including the nature and extent of such participation, academic and experiential requirements, and standards of professional conduct. Its purpose is to provide guidance to audiologists, other professionals, and the industrial community.

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Technical Report

Introduction

This technical report has been formulated to offer guidance to audiologists, related professionals, and consumers of occupational and nonoccupational hearing conservation services in the following areas:

  • preparation of the audiologist to provide hearing conservation services;

  • role of the audiologist on the interdisciplinary team in hearing conservation;

  • components of service delivery in hearing conservation; and

  • professional ethics related to service delivery in hearing conservation.

For the purpose of this discussion, occupational hearing conservation is defined as the prevention of significant, permanent hearing loss resulting from on-the-job exposure to ototoxic or ototraumatic agents (of which noise is the most common) in workers (employees and military personnel). Nonoccupational hearing conservation refers to the prevention of significant, permanent hearing loss resulting from off-the-job exposure to ototraumatic agents (most commonly noise) in persons of all ages.

Audiologists are knowledgeable about normal and abnormal anatomy and physiology of the auditory and vestibular systems and their response to ototraumatic agents (most commonly noise). Their educational and clinical background prepares audiologists to assume a variety of roles with expertise related to the prevention of significant, permanent hearing loss resulting from on-and off-the-job exposure to ototraumatic agents (most commonly noise).

Following the report are appendices including historical background information and bibliographies of references and training materials.

Noise-induced hearing loss (NIHL) is the most common occupational disease and the second most self-reported occupational illness or injury, according to the National Institute for Occupational Safety and Health (NIOSH, 1998b). Approximately 30 million American workers are sometimes exposed on the job to sound levels exceeding 75–80 dBA (decibels sound pressure level measured using the A frequency-weighting network on a sound level meter), but not all of these persons have daily equivalent noise exposures constituting a hazard to hearing. An additional 9 million are at risk for hearing loss from exposure to other agents such as solvents and heavy metals, which may act either independently of noise to cause hearing damage, or synergistically with simultaneous noise exposures (NIOSH, 1998b). According to the National Institute for Deafness and Other Communicative Disorders (NIDCD), 20 million workers have regular workplace noise exposure to daily equivalent sound levels of 75 dBA or more, which is the lower limit of exposure considered capable of causing any measurable noise-induced hearing damage over a lifetime. Estimates of the number of persons exposed to daily equivalent sound levels of 85 dBA or higher (deemed hazardous) vary from 5 million (NIOSH, 1998a) to 9 million (Simpson & Bruce, 1981).

The term NIHL connotes gradually progressive sensorineural hearing damage resulting from months or years of repeated exposure to hazardous sound levels. Scientists agree that there is a hearing hazard from daily 8-hour continuous equivalent values equal to or exceeding 85 dBA. Damage at lower daily equivalent sound levels will be minimal, and many scientists consider the hazard at such lower levels to be insignificant. As daily equivalent exposure increases above 85 dBA, however, the hearing hazard increases substantially. A widely accepted model predicting the amount of total hearing loss resulting from the combined effects of noise exposure and age-effect hearing change is available in the American National Standards Institute (ANSI) Standard S3.44-1996, Determination of Occupational Noise Exposure and Estimation of Noise-Induced Hearing Impairment (ANSI, 1996).

Another type of noise-induced hearing damage is referred to as acoustic trauma, a term that connotes permanent mechanical cochlear injury resulting immediately from a single exposure to very high sound pressure levels or to blast waves. Acoustic trauma is usually associated with impulsive sound sources (such as explosions, gunfire, firecrackers, or air bag deployment) or with sound sources that are activated very close to the ear (such as early cordless telephone ringers or toys used inappropriately by small children). Damage risk criteria related to acoustic trauma are under consideration by an ANSI Working Group S3/WG62, and criteria for safe weapons-fire exposures serve as guidelines in military training. However, incidents of acoustic trauma are usually unfortunate accidents that are best prevented by foreseeing and eliminating the potentially hazardous situation.

Occupational hearing conservation programs (OHCPs) are implemented when potentially hazardous exposures are present in the workplace. The term hearing loss prevention program (HLPP) has come into use recently (NIOSH, 1998a) to emphasize the importance of proactively avoiding the development of any significant occupational hearing loss resulting from exposure to noise and other agents. HLPPs may also include educational efforts in schools to teach young people about the dangers of noise exposure, the value of their sense of hearing, and ways to protect their hearing from hazards throughout their lives.

Audiologists have been involved in noise-related issues since the inception of the profession (see Appendix 1, Historical Perspective), and they continue to be active today. According to the 1994 ASHA Omnibus Survey, 45% of audiologists provided some OHCP services as part of their job (ASHA, 1994). This percentage increased to more than 56% in the 1999 Omnibus Survey (ASHA, 1999). The services most commonly provided by audiologists were audiologic follow-up evaluations in response to HCPs monitoring audiometry, fitting and dispensing of hearing protection devices, and review of monitoring audiograms. Fewer audiologists surveyed reported that they supervise OHCPs or serve as consultants to industry, and even fewer are involved in noise measurement, training of occupational hearing conservationists (OHCs) or other technicians, or HCP audits and program evaluations. Although the percentage of all audiologists whose practices focus on occupational hearing conservation is small, audiologists play a leading role in the hearing conservation field, and the large majority of OHC training course directors certified by the Council for Accreditation in Occupational Hearing Conservation (CAOHC) are audiologists.

The delivery of quality hearing conservation services by audiologists involved in these activities depends on proper academic preparation, professional experience, and adherence to standards of professional conduct. Audiologists for whom hearing conservation is a secondary or minor focus must ensure that they have mastered the details concerning NIHL and its prevention, as well as the regulations that apply to occupational noise exposures, before offering services in support of HCPs. Those audiologists who have made the effort to gain expertise in noise-related technical information (plus other ototraumatic hazards) can take a valuable leadership role in interdisciplinary hearing conservation teams. The audiologist brings special knowledge about hearing and communication to the OHCP team.

For hearing loss prevention to be effective, the interaction of professional disciplines—such as audiology, occupational medicine, otolaryngology, occupational health nursing, industrial hygiene, engineering, and safety—in the implementation of OHCPs is vital. Audiologists with a strong background in all aspects of hearing conservation (including audiometric monitoring and interpretation of audiograms, equipment calibration, noise exposure assessment, hearing protection devices, and education for workers, management, and other HCP team members) can offer appropriate guidance and leadership in the development and continuing implementation of OHCPs.

Virtually every audiologist will encounter patients of all ages who are at risk of developing NIHL (or exacerbating preexisting NIHL) through nonoccupational noise exposure (perhaps in combination with noisy jobs). Therefore, all audiologists need to become familiar enough with NIHL prevention strategies to offer useful education and advice to these patients and their families. Annoying or debilitating tinnitus is frequently associated with NIHL, and noise exposure may cause tinnitus even prior to NIHL development (American Tinnitus Association, 1997). Therefore, audiologists must be prepared to counsel clients about tinnitus prevention, evaluation, and management in relation to noise exposure.

In today's complex society, noise exposure poses an increasingly serious threat to individuals' hearing. Of approximately 28 million people in the United States with impaired hearing, nearly 10 million of these cases are associated with hazardous noise exposure (NIDCD, 1996 ; NIDCD, 1999). It is difficult to quantify the number of Americans exposed to hazardous noise levels during nonoccupational activities. Examples of such activities include firearms shooting, auto races, woodworking, use of chain saws and other power tools, listening to over-amplified music, and so forth. Unlike some occupational exposures, nonoccupational noise exposures are not controlled by any regulations or guidelines. Recently, a national public awareness campaign known as “Wise Ears!” (http://www.nidcd.nih.gov/nidcd/health/wise/index.htm) has begun directing attention and efforts toward nonoccupational hearing loss prevention. Hearing loss prevention is also included in several of the goals of the Healthy People 2010 initiative: Its objectives include reducing work-related NIHL and nonoccupational NIHL in the public (children, adolescents, and adults), with specific mention of increasing the use of hearing protection devices ( U.S. Department of Health and Human Services, 2000).

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Preparing the Audiologist to Provide Occupational Hearing Conservation Services

Core Academic Preparation. Graduate education programs in audiology that are accredited by ASHA's Council on Academic Accreditation (known prior to January 1996 as the Educational Standards Board) offer core curricula that include the following areas (ASHA, 1997):

  1. Auditory disorders, such as (a) pathologies of the auditory system and (b) assessment of auditory disorders and their effect on communication;

  2. Habilitative/rehabilitative procedures, such as (a) selection and use of appropriate amplification instrumentation for the hearing impaired and (b) management procedures for speech and language habilitation and/or rehabilitation of the hearing impaired (that may include manual communication);

  3. Conservation of hearing, such as (a) environmental noise control in the testing room and (b) identification audiometry (school, military, industry); and

  4. Instrumentation, such as (a) electronics, (b) calibration techniques, and (c) characteristics of amplifying systems.

Specialized Preparation. In recent years, some graduate programs have expanded their offerings in noise and hearing conservation because of increased interest on the part of audiologists and the general public in noise issues. Some programs offer special curricula in the area of occupational audiology. These curricula supplement a basic program of study in audiology with specialized courses and reference materials from other university departments, such as industrial hygiene, engineering, business, and public health. Ideally, all graduate audiology programs should emphasize hearing conservation by offering specialized courses and practicum experiences relevant to the skills and knowledge needed by the professional intending to work in the area of occupational hearing conservation. The audiologist-in-training should have extensive practicum experience in working on-site in an occupational setting under the supervision of an audiologist experienced in occupational hearing conservation. This practicum should include activities in all seven of the components of a model HCP (see later section, Components of Service Delivery in Occupational Hearing Conservation).

Many audiologists decide to expand their expertise in hearing conservation topics after they have completed their graduate degrees. Distance learning, teleconferences, and short courses can provide the needed supplemental training. Many educational opportunities exist for audiologists already working professionally to expand and update their skills and knowledge in hearing conservation. These include continuing education programs offered by professional associations (such as ASHA, the National Hearing Conservation Association [NHCA], the Acoustical Society of America [ASA], the American Industrial Hygiene Association [AIHA], the American Academy of Audiology [AAA], and CAOHC), as well as universities and equipment manufacturers.

Whether the training occurs during pursuit of an academic degree or later, the audiologist intending to work in hearing conservation should acquire expertise in the following areas:

  1. Auditory effects of noise on humans, including noise exposure metrics (e.g., daily average exposures normalized to 8 hours such as Occupational Safety and Health Administration [OSHA] TWA and LA8hn, spectral measures such as octave-band sound pressure levels, addition of sound levels from multiple noise sources, and annoyance-related measures such as day-night average sound levels), as well as damage risk criteria for habitual exposures and for single-exposure acoustic trauma (Henderson & Hamernik, 1995;

  2. The effects of noise on communication and job performance, including use of metrics such as the Speech Interference Level or the Speech Intelligibility Index for predicting the masking of speech by noise (Robinson & Casali, 2000);

  3. Community noise annoyance criteria (Driscoll, 2000);

  4. Nonauditory effects of noise on health (Berglund & Lindvall,1995; Passchier-Vermeer, 1996);

  5. Federal, state, and local noise regulations;

  6. Development, organization, and administration of OHCPs via an interdisciplinary team approach including the effective integration of contracted services when needed to supplement the employer's resources (J. D. Royster & Royster, 1990; Stewart, 2000);

  7. Program audits and evaluations of effectiveness (J. D. Royster & Royster, 1999, 2000; ANSI, 1991);

  8. Workers' Compensation regulations and trends, and methods of claim evaluation (Dobie & Megerson, 2000);

  9. Physical characteristics of personal hearing protection devices (HPDs), methods for selecting HPDs appropriate for workplace demands and wearer's needs, techniques for fitting and user training, realistic field performance estimates, and methods for field evaluations of attenuation (Berger, 2000; L. H. Royster, 1995; NHCA, under development);

  10. Criteria of CAOHC for certification of OHCs (CAOHC, 2000), and other recommendations for training and supervising OHCs and other technicians (NHCA, 1987);

  11. Educational and motivational concepts and techniques for employees and management (L. H. Royster & Royster, 2000);

  12. Noise measurement instrumentation, techniques for conducting noise surveys, and evaluation of the resulting noise exposure data (Earshen, 1999, 2000; L. H. Royster, Berger, & Royster, 2000);

  13. Principles of noise control (Driscoll & Royster, 2000; Erdreich, 1999);

  14. Forensic audiology (Dobie, 1993; Kramer & Armbruster, 1982);

  15. Business and human resources management;

  16. Information management techniques and applications (Cook, 1999);

  17. Marketing of audiology services; and

  18. Business report writing.

Additional Credentials. Audiologists who meet the experience and educational requirements may become certified by CAOHC to serve as course directors entitled to lead training courses for persons seeking certification as OHCs. Audiologists may also obtain specific knowledge relating to occupational hearing conservation by attending the course director training offered by CAOHC or the new professional supervisor training under development by CAOHC designed for audiologists or physicians who supervise OHCs in OHCPs.

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Audiologist's Role on an Interdisciplinary Team in Occupational Hearing Conservation

Audiologists must be qualified by education and experience if they are to assume a leadership role in the development and implementation of OHCPs. In this role, they should cooperate with members of other disciplines and coordinate activities to enhance the proper development and operation of effective programs. The other professional disciplines may include acoustical engineering, industrial engineering, otolaryngology, occupational medicine, safety engineering, occupational health nursing, industrial hygiene, human resource management, and information management, as well as technicians (including OHCs) with specific OHCP duties. The extent of involvement of each discipline will be determined by the employers' needs, resources, and organizational structure. Regardless of which professionals may serve as consultants to the OHCP, the everyday leadership of an on-site key individual is critical to the success of the program (J. D. Royster & Royster, 1990; Stewart, 2000).

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Components of Service Delivery in Occupational Hearing Conservation

A model HCP includes seven general components:

  1. Noise exposure assessment;

  2. Engineering noise controls and administrative controls of noise exposure (the approaches preferred instead of the use of personal HPDs to reduce employees' noise exposures);

  3. Personal hearing protection, including its selection, user fitting and training, and supervised use;

  4. Audiometric testing, audiogram review, and follow-up steps, including referral as needed;

  5. Education and motivation of management and workers;

  6. Recordkeeping; and

  7. Analysis of program effectiveness.

The audiologist participates in each program component to a greater or lesser extent depending on his or her education and skills and the particular employer's needs and resources. The audiologist can advise management on many operational aspects of the hearing conservation program, including management responsibilities and liabilities under federal, state, and local occupational health and safety regulations and Workers' Compensation statutes. The audiologist can recommend the most successful and cost-effective means of implementing each component of the program, considering the advantages and disadvantages of developing in-house resources versus contracting with external service providers (J. D. Royster, 2000; Stewart, 2000;).

Employers should be aware that the scope of practice of OHCs and other technicians is limited (CAOHC, 2000), and that OSHA requires that they be supervised by an audiologist, otolaryngologist, or other physician. Additionally, state regulations may dictate the scope of practice of the OHC/technician.

In many workplaces, some OHCP components (such as audiometric testing, basic hearing-related education, and the provision of HPDs for off-job use) may be offered as part of a wellness program to employees who are not noise-exposed or whose noise exposures are too low to require inclusion in the OHCP. The audiologist can advise management regarding appropriate schedules for audiometric monitoring of these persons (whose data provide a desirable control group for comparison to data from employees included in the OHCP), as well as policies for follow-up recommendations if hearing losses are identified.

In addition to the basic components of an effective OHCP, audiologists may be involved in forensic activities, such as serving as expert witnesses in hearing loss compensation claim cases and other forms of litigation (such as product liability).

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Noise Exposure Assessment

The purposes of noise exposure monitoring include determining whether there is a need for an OHCP; identifying appropriate strategies for the protection of exposed workers via noise control and the use of appropriately selected HPDs; documenting workers' noise exposures for use in interpreting their audiometric results; and evaluating potential Workers' Compensation claims. The audiologist, industrial hygienist, or acoustical engineer, with the appropriate background and training, performs area noise measurement, personal dosimetry, related equipment calibration activities, and data analysis. The professional then documents the results and shares them with the HCP team. Alternatively, these professionals may choose to (a) train and supervise a person within the organization to perform these measurements or (b) recommend a consultant to conduct the survey and analyze and report the results. For guidance on these topics, see L. H. Royster, Berger, and Royster (2000).

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Engineering Noise Controls and Administrative Controls

The preferred method to reduce employee noise exposure is implementation of engineering noise controls to reduce noise at the source (e.g., machinery modification), along the path to the receiver (e.g., room treatments or machine enclosures), or at the receiver's position (e.g., worker enclosures or control booths). Engineering controls are usually the domain of the acoustical engineer or other consultants with noise control expertise. Administrative controls involve the reassignment of noisy tasks among employees to spread noise dose among several workers, hopefully while keeping total noise dose at safe levels for each person. Another type of administrative control is long-term planning to replace noisy equipment with quieter alternatives.

The feasibility of administrative noise controls should be determined by the employer. The audiologist should be involved in consultation to determine the value of both engineering and administrative controls in reducing the risk of hearing damage. Reducing exposures through noise controls is desirable even when non-hazardous levels cannot be achieved; hearing protection may still be necessary after control measures are implemented. The audiologist should be familiar with engineering consultants whom he or she can recommend to the employer. For summaries on these topics, see Driscoll and Royster (2000), Erdreich (1999), and Harris (1991).

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Personal Hearing Protection

When the elimination of overexposure to noise through engineering and/or administrative controls is not feasible (or until such controls are in place), a personal hearing protection program must be implemented. The audiologist is the key team member in solving problems related to the use of HPDs. Such problems may include the inability of wearers to hear speech and other signals (especially for wearers who are hearing-impaired), the inability to reduce exposures to a “safe” level, and worker dissatisfaction with devices that are uncomfortable or impractical in the work environment. The audiologist should advise the employer on the selection of appropriate personal hearing protection given the nature and extent of employee noise exposures and his or her knowledge of attenuation characteristics of specific types of hearing protectors, plus practical considerations. The audiologist can fit personal hearing protection and instruct and motivate workers regarding its proper use and care. Because it is critical for on-site staff to be knowledgeable about HPDs, the audiologist can also train and supervise OHCs, industrial hygiene and safety personnel, and front-line supervisors regarding appropriate procedures for fitting and issuing hearing protectors to workers as well as supervise consistent, correct use of HPDs. For guidance, see Berger (2000).

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Audiometric Testing, Audiogram Review, and Follow-Up

The audiometric phase is central to the mission of an OHCP. Only prompt counseling and follow-up in response to significant threshold shifts (that ideally are still temporary shifts) in individual employees can prevent the development and progression of NIHL. On a group basis, the audiometric data also indicate the effectiveness of the OHCP (see later section). For a summary, see J. D. Royster (2000).

The audiologist should take a leadership role in the delivery of the following services:

  1. Advise management on the relative merits of different approaches to audiometric testing (inhouse, by mobile providers, or by off-site clinics; with tests performed by OHCs or by audiologists) (Stewart, 2000).

  2. Advise management on the suitability of various types of audiometers (e.g., manual, self-recording [previously common but now largely obsolete], microprocessor, and software-driven) and potential differences in the data acquired by different methods.

  3. Advise management regarding computer management of audiometric test results and related records (Cook, 1999).

  4. Train, retrain, and supervise OHCs and other technicians in testing and associated counseling and recordkeeping activities.

  5. Select and maintain audiometric equipment and ensure its correct and consistent calibration.

  6. Select suitable audiometric testing areas and document that ambient noise levels meet not only regulatory requirements, but also more stringent consensus standards (ANSI, 1999; NHCA, 1996).

  7. Provide or recommend appropriate audiometric services including routine monitoring audiometry and retesting of workers with problem audiograms.

  8. Review and interpret audiometric tests, including those performed by OHCs and other technicians.

  9. Determine or assist in determining, through evaluation or referral, work-relatedness of hearing loss for the purposes of otologic and/or audiologic referral and recording on the OSHA 300 Log.

  10. Provide meaningful written feedback and recommendations to employees concerning their audiogram results.

  11. Identify and implement criteria for retesting and for the identification of problem audiograms requiring professional review (including but not limited to OSHA standard threshold shift [STS], which is a change from baseline of 10 dB in the average of thresholds at 2000, 3000, and 4000 Hz in either ear) for use by OHCs, other technicians, and management (NHCA, under development).

  12. Refer clients to appropriate facilities for audiologic and/or otologic evaluation by professionals who are familiar with occupational hearing conservation concepts, following consistent referral criteria (American Academy of Otolaryngology-Head and Neck Surgery [AAO-HNS], 1997; NHCA, under development).

  13. Revise audiometric baselines for persistent improvement or for persistent OSHA STS following consistent criteria such as guidelines developed by NHCA (NHCA, 1996).

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Education and Motivation

One of the most important components of an effective HCP is the education and motivation of workers and management (Gasaway, 1985; L. H. Royster & Royster, 2000). The audiologist may perform the following activities:

  1. Provide programs tailored to the needs of the audience (i.e., HCP team members, employee work groups, supervisors, and upper management).

  2. Develop or recommend appropriate educational materials.

  3. Instruct in-house staff in effective methods of motivating and educating workers.

  4. Contribute to management education by preparing articles for publication or speaking before trade and management groups.

  5. Maintain up-to-date knowledge of pertinent local, state, and federal regulations in order to provide management with accurate information concerning these matters.

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Recordkeeping

An accurate and complete recordkeeping system is a requisite element of an OHCP to verify compliance with relevant regulations and to ensure that internal standards are followed. The audiologist should advise the employer of required and recommended records that should be maintained in-house to document each of the components of the program, as well as to be prepared for potential Workers' Compensation claims. In addition, the audiologist should establish and maintain an adequate recordkeeping system for all services provided for an employer—whether direct, supportive, or consultative—and share those records with the employer as needed.

In January of 2001, OSHA issued recording criteria for cases of occupational hearing loss ( Federal Register, 2001). Employees showing an STS must be recorded on the OSHA Form 300 Log by checking the “hearing loss” column. This requirement refers to work-related hearing loss and applies to employees with workplace noise exposure of 85 dBA or greater for an 8-hour time weighted average or a total noise dose of 50%.

A subsequent “final rule” from OSHA in the July 1, 2002 issue of the Federal Register postponed the implementation of the final rule to January 1, 2003. Retesting of hearing within 30 days of the first test is allowed. Implementation of a separate column for hearing loss recording is delayed to January 2004.

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Analysis of Program Effectiveness

Program evaluation provides meaningful feedback to all levels of personnel involved in the implementation and management of the OHCP. Analysis of program effectiveness is beneficial in the following ways (J. D. Royster & Royster, 2000; ANSI, 1991):

  1. Assess regulatory compliance and adherence to more stringent internal standards through on-site audits of not only the completion of program activities, but also the quality of their implementation.

  2. Provide statistical analyses of the incidence of OSHA STSs or more stringent significant threshold shifts in groups of workers (new workers vs. senior workers, departments with varying noise exposures, departments with varying HPD use policies, etc.).

  3. Provide statistical analyses of the variability of the audiometric database, indicating whether the data are of sufficient quality to allow identification of incipient threshold shifts during individual audiogram review as well as group-data epidemiological analyses.

  4. Assist management in determining an appropriate course of action when undesired hearing threshold changes or patterns are identified in various worker populations.

  5. Detect specific problem areas where improvement may be needed in the program.

  6. Provide important information to management on the benefits derived from the program.

  7. Identify quality improvement issues (e.g., trends in elevated thresholds at 500 Hz that may indicate excessive ambient noise levels, a pattern of elevated thresholds for a given audiometer indicating a possible equipment malfunction or examiner error, etc.).

The above list is in no way comprehensive. Rather, it is included to provide the reader with some rationale for including program analysis as a component of a complete OHCP.

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Issues in Hearing Conservation

Because hearing conservation is an evolving field, concerned audiologists must be aware of emerging and ongoing issues. The following issues are not listed in any particular order and are not all-encompassing. Other issues will certainly arise in the future.

  1. The audiologist's role in occupational hearing conservation is not limited to preventing hearing loss from noise. The audiologist must be concerned with any hearing loss issues resulting from or complicated by the work environment. For example, an audiologist might be consulted in a work situation where diving caused a ruptured tympanic membrane; where welding sparks caused a perforation in the tympanic membrane; where high altitude created middle ear pain and/or hearing problems; where medications were being monitored for ototoxicity using hearing testing; where audiologic and/or medical referrals were being made for nonoccupational ear or hearing problems; where a traumatic accident resulted in a Workers' Compensation claim; where Americans With Disabilities Act (ADA) issues were identified; where hearing loss prevention programs were needed for companies without hazardous noise, and so forth.

  2. NIOSH (1998a) has issued a new criteria document for occupational noise exposure, which suggests numerous changes to the OSHA noise regulations. Although this document does not have the enforcement status of a regulation and there is debate about some of the recommendations, professionals may wish to consider voluntary implementation of some of its ideas to enhance HCP effectiveness. For more information, see Miller (1999) and Franks (1999).

  3. Hearing qualification criteria have been established for entry into certain hearing-critical jobs or to maintain qualification for continued employment in such positions (LaCroix, 1996; MacLean, 1995; MacLean & Danielson, 1996). Audiologists currently perform audiologic evaluation of employees or job applicants with respect to such hearing criteria. Scientific justification for the establishment or modification of job-related criteria is an area in which audiologists can contribute.

  4. OSHA's STS is not an early-warning indicator of incipient NIHL; most audiologists agree that for OHCPs to prevent NIHL, precursor significant threshold shifts should be identified so that employees can be counseled and HPD adequacy can be improved to stop hearing loss trends. The application of age corrections (as allowed by OSHA) delays employee follow-up unless the reviewing audiologist reacts to precursor shifts, not just OSHA STSs. The audiologist should advise management regarding OHCP policies that would ensure that communicatively significant threshold shifts receive prompt follow-up attention. Alternatives have been suggested (NIOSH, 1998a; J. D. Royster, 2000). Moreover, OSHA STS rates do not provide a reliable indication of OHCP quality; audiologists need to consider numerous factors in interpreting STS rates (J. D. Royster, 2000).

  5. In medico-legal arenas, recent attention has been given to possible strategies for the allocation of hearing loss among alternative contributing causes, such as aging, noise exposure, and otological pathology (AAO-HNS, 1998; Dobie, 1993; Lipscomb, 1999.

  6. Hearing-impaired employees in noisy occupations may benefit from the appropriate use of amplification, assistive listening devices, reasonable accommodations, and audiologic rehabilitation. The audiologist can advise management and individual employees regarding these matters on a case by case basis, taking into consideration ADA compliance, workplace safety, and the welfare of the hearing-impaired employee. The use of amplification in hearing conservation areas should be allowed only with caution so as to ensure that the device does not cause further hearing damage due to high sound levels produced at the ear of the wearer. Special devices that combine amplification with hearing protection may be considered. Evaluation of the individual and the work environment is required to identify possible solutions to the problem.

  7. Potential noise effects on unborn fetuses are of concern, although exposure criteria proposed by the American Conference of Governmental Industrial Hygienists (ACGIH, 1999) indicate that there is no problem at the noise exposure levels present in most occupations.

  8. Labeling of the attenuation values (Noise Reduction Rating [NRR] values) on HPDs according to specifications promulgated by the Environmental Protection Agency (EPA, 1979) does not reflect actual field performance (Berger, 1999, 2000). ASHA participated in a coalition of professional associations known as the Task Force on Hearing Protector Effectiveness, which has asked EPA to revise labeling requirements to reflect more realistic real-world attenuation (L. H. Royster, 1995). Although a more realistic test method is now included in ANSI S12.6-1997, product data measured using this method are not widely available. Efforts should continue to implement more accurate and useful estimates of HPD effectiveness, and professionals should take this into account when recommending devices.

  9. Nonoccupational exposures to hazardous noise continue to harm the hearing health of individuals of all ages. Currently, no standards exist for limiting these exposures or labeling the noise levels produced by most products in order to allow consumers to “buy quiet” on an absolute basis (as opposed to the relative noise-level rankings of products that are sometimes provided in consumer product-rating publications). ANSI Working Group S12/WG38 is developing consensus standards for product noise labeling.

  10. Public awareness of the hazardous effects of excessive noise should be initiated at an early age to instill appropriate self-protective behaviors. There are several educational programs available for different age groups of young people (see Appendix 3). ASHA audiologists are participating in the Task Force for Hearing Conservation Education in the Schools. This task force, whose mission is the prevention of hearing loss through the education of school-aged children, is developing hearing conservation curricula and lobbying for their inclusion in the elementary school program, as well as developing strategies for funding.

  11. Many workers exposed to hazardous noise (e.g., workers in construction, agriculture, and oil well drilling and servicing) either are not covered or are inadequately covered by hearing conservation regulations.

  12. There is general professional agreement that the OSHA and Mine Safety and Health Administration (MSHA) regulations represent minimal requirements; regulatory compliance does not ensure that an HCP will be effective. Audiologists should advise their clients to follow the concepts and techniques that a body of experts have found to be consistent with successful OHCPs, and should ensure that the services provided to those clients meet standards of good practice (AIHA/NHCA, 2000; Franks, Stephenson, & Merry, 1996; J. D. Royster & Royster, 1990).

  13. Recent research suggests that some chemicals are ototoxic in and of themselves, whereas some substances act synergistically with noise exposure to injure the auditory system. However, noise is the only hearing-harmful agent for which OHCPs are required. The audiologist needs to keep abreast of emerging evidence concerning the ototoxic effects of chemical exposures, either alone or when combined with noise exposure. The audiologist must be familiar with these agents and must know their potential harm, how to test for their effects, and how to protect employees against exposure to them. Examples of such agents include certain gases, heavy metals, and aromatic solvents. For research summaries, see Cary, Clarke, and Delic (1997); Fechter (1995); Franks and Morata (1996); and Johnson and Nylen (1995). The use of vestibular screening, otoacoustic emissions testing, and acoustic reflex measurements (elevation, absence, or decay) all hold promise for allowing the early identification of employees who are susceptible to hearing damage from combined exposures.

  14. Community noise is a growing concern for annoyed citizens, who often need professionals' help in effectively voicing the need for control of environmental noise to urban planners and local governments. For summaries, see Driscoll, Stewart, and Anderson (2000); Berglund and Lindvall (1995); and Passchier-Vermeer (1996).

  15. Monitoring audiometry, whether part of an HCP or a school health program, may identify potentially treatable conductive and retrocochlear pathologies as well as other causes of sensorineural hearing loss in addition to NIHL. Costeffective referral criteria should be followed. Criteria are being developed by NHCA (under development).

  16. ADA affects the hiring and/or retention of employees with hearing loss in noise-hazardous or hearing-critical jobs. A problem faced by audiologists and other health and safety professionals is the lack of objective measures with which to predict the ability of an individual with hearing loss to perform job-related tasks.

  17. Active noise reduction shows promise for reducing the hazardous levels of noise in certain environments. Its usefulness is limited to relatively stable, low-frequency noises in well-defined spaces (such as tonal noise from smokestacks). However, active-noise-reduction earmuffs may benefit employees in extremely high levels of low-frequency noise.

  18. Special HPDs, such as flat-attenuation and moderate-attenuation devices and electronic communication devices, may be appropriate to enhance auditory function in certain environments and for certain individuals.

  19. Otoacoustic emissions testing may provide predictive information to identify noise-susceptible individuals prior to the development of hearing threshold shifts.

  20. The information-processing abilities of individuals with hearing loss, as well as those individuals with normal hearing, must be considered in the design and use of warning signals (both auditory and in alternative sensory modes). This area of psychoacoustics and ergonomics involves many disciplines; more involvement by audiologists is needed.

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Professional Ethics Related to Service Delivery in Occupational Hearing Conservation

Preservation of the highest standards of integrity and ethical principles is vital to the responsible discharge of obligations in the profession of audiology. The ASHA Code of Ethics (1994) sets forth the fundamental principles and rules considered essential to this purpose. It contains several principles and rules that are especially relevant to the provision of hearing conservation services.

Principle of Ethics I states that “individuals shall honor their responsibility to hold paramount the welfare of persons they serve professionally.” The audiologist providing services under contract or on a fee-for-service basis must attempt to the best of his or her ability to serve the welfare of both the employer and the noise-exposed individual. This principle relates specifically to the area of audiometric testing, audiogram review, and medical/audiologic referral. Information regarding auditory status and related matters should be made available to the exposed individual.

Principle of Ethics I, Rule E, states that “individuals shall evaluate the effectiveness of services rendered and products dispensed and shall provide services or dispense products only when benefit can reasonably be expected.” In developing referral procedures, the audiologist should avoid actual or potential conflict of interest. The referred worker should be given a choice of referral specialists or facilities. If the audiologist is under contract to provide services on behalf of the company, referrals to the audiologist's private practice may not be appropriate and should be avoided. Referrals should be made to audiologists who hold the CCC-A, are licensed in states that require licensure, and are experienced and competent in the area of occupational hearing conservation. The audiologist providing or supervising hearing conservation services must develop or use currently available methods of measuring the effectiveness of these services and products. Products dispensed (such as HPDs) should be appropriate for the workplace in which they will be used. The audiologist should not derive financial or other benefit from the recommendation of one product or piece of equipment over another.

Principle of Ethics II states that “individuals shall honor their responsibility to achieve and maintain the highest level of professional competence.” An audiologist intending to provide hearing conservation services must be properly prepared to offer these services through either preservice and/or in-service training and experiential activities.

Principle of Ethics II, Rule D, states that “individuals shall delegate the provision of clinical services only to persons who are certified or to persons in the education or certification process who are appropriately supervised. The provision of support services may be delegated to persons who are neither certified nor in the certification process only when a certificate holder provides appropriate supervision.” It is the responsibility of audiologists who supervise OHCs and other technicians in hearing testing, personal hearing protection fitting, and recordkeeping to maintain adequate supervision of such persons to ensure their continued competency.

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Summary

Exposure to noise poses a continuing hazard to the hearing health of millions of individuals. The development and implementation of effective OHCPs and other HLPPs can and will prevent needless cases of hearing loss. Audiologists are especially qualified to exercise a leadership role in the development and implementation of HCPs. This position statement has addressed issues germane to the participation of audiologists in HCPs, including the nature and extent of such participation, academic and experiential requirements, and standards of professional conduct. Its purpose is to provide guidance to audiologists, other professionals, and the industrial community.

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References

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American Conference of Governmental Industrial Hygienists. (1999). 1999 TLVs and BEIs. Cincinnati, OH: Author. [Note: this publication is updated annually—see the latest edition.].

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Berglund, B., & Lindvall, T. (Eds.). Community noise. 1995. Archives of the Center for Sensory Research 2(1), a monograph prepared for World Health Organization. Sweden: Stockholm University.

Cary, R., Clarke, S., & Delic, J. (1997). Effects of combined exposure to noise and toxic substances: Critical review of the literature. Annals of Occupational Hygiene, 41, 455–465.

Cook, G. R. (1999). Managing occupational hearing conservation data. The Hearing Review, 6(9), 74–78.

Council for Accreditation in Occupational Hearing Conservation. Handbook for course directors. 2000. Milwaukee, WI: Author. (Also see web page http://www.caohc.org)

Dobie, R. A. (1993). Medical-legal evaluation of hearing loss. New York: Van Nostrand Reinhold.

Dobie, R. A., & Megerson, S. C. (2000). Workers' compensation Chap. 18. In E. H. Berger, L. H. Royster, J. D. Royster, D. P. Driscoll, & M. A. Layne (Eds.), The noise manual (5th ed.). Fairfax, VA: American Industrial Hygiene Association.

Driscoll, D. P., & Royster, L. H. (2000). Noise control engineering Chap. 9. In E. H. Berger, L. H. Royster, J. D. Royster, D. P. Driscoll, & M. A. Layne (Eds.), The noise manual (5th ed.). Fairfax, VA: American Industrial Hygiene Association.

Driscoll, D. P., Stewart, N. D., & Anderson, R. R. (2000). Community noise Chapter 15. In E. H. Berger, L. H. Royster, J. D. Royster, D. P. Driscoll, & M. A. Layne (Eds.), The noise manual (5th ed.). Fairfax, VA: American Industrial Hygiene Association.

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Earshen, J. J. (2000). Sound measurement: Instrumentation and noise descriptors Chap. 3. In E. H. Berger, L. H. Royster, J. D. Royster, D. P. Driscoll, & M. A. Layne (Eds.), The noise manual (5th ed.). Fairfax, VA: American Industrial Hygiene Association.

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Franks, J. R., & Morata, T. C. (1996). Ototoxic effects of chemicals alone or in concert with noise: A review of human studies. In A. Axelsson, H. M. Borchgrevink, R. P. Hamernik, P. A. Hellstrom, D. Henderson, & R. J. Salvi (Eds.), Scientific basis of noise-induced hearing loss (pp. 437–446). New York: Thieme.

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Henderson, D., & Hamernik, R. (1995). Biologic bases of noise-induced hearing loss. Occupational Medicine: State of the Art Reviews, 10, 513–534.

Johnson, A. C., & Nylen, P. (1995). Effects of industrial solvents on hearing. Occupational Medicine: State of the Art Reviews, 10, 623–640.

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LaCroix, P. (1996). Hearing standards and employment decisions: The federal model. Spectrum, 13(3), 6–8.

Lipscomb, D. M. (1999). Allocation among causes of hearing loss: The concept, its pros and cons. The Hearing Review, 6(9), 48, 61-64.

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MacLean, S., & Danielson, R. (1996). Hearing standards in the U.S. military. Spectrum, 13(1), 16–17.

Miller, M. H. (1999). Occupational hearing conservation: Unique challenges and opportunities. The Hearing Review, 6(9), 8–16.

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Appendix 1: Historical Perspective

The profession of audiology developed as a response to hearing problems stemming from noise exposure, specifically military noise exposure during World War II (McLauchlin, 1978). After this initial development phase, the profession gradually turned its research and academic interests toward other areas of audiologic practice. However, audiologists affiliated with military and VA facilities maintained a strong involvement in occupational hearing conservation efforts. After compensation claims for noise-induced hearing loss (NIHL) began to be filed in the late 1940s and early 1950s, interest in occupational hearing conservation grew in the private sector.

In 1965, the U.S. Department of Labor (DOL) included “industrial audiology” in a list of specializations recognized as part of audiologic practice in its Dictionary of Occupational Titles.

In 1969, the DOL issued a noise standard under the authority of the Walsh-Healy Public Contracts Act. This standard was subsequently extended to the majority of American workers under the Occupational Safety and Health Act of 1970 and the 1971 Occupational Noise Exposure Standard. In 1974, the DOL proposed a revision to the noise standard, which included requirements for hearing conservation programs.

On January 16, 1981, the Occupational Safety and Health Administration (OSHA) issued a standard for hearing conservation programs as an amendment to the existing noise standard (U.S. DOL, 1981a). Because the standard was published so close to the advent of a new presidential administration, the effective date of the standard was delayed. Portions of the standard became effective on March 8, 1983 (U.S. DOL, 1983). The American Speech-Language-Hearing Association (ASHA) was instrumental in achieving enactment of the amendment through its testimony and that of many of its members. This final rule specifically names the audiologist as one of three categories of professionals responsible for the audiometric testing program. (For additional information on the history of federal noise standards, refer to Suter [1994], as well as current developments discussed in Franks [1999]).

On March 8, 1983, OSHA issued the final Hearing Conservation Amendment to its Occupational Noise Exposure Regulation (29 CFR 1910.95; U.S. DOL, 1981b). OSHA estimated that implementation of the amendment could reduce the number of American workers with occupational hearing impairment from more than 1 million to 261,000 by the year 2020. Beyond the prevention of NIHL, the amendment was intended to produce occupational hearing conservation programs (OHCPs) that may reduce the incidence of stress-related illnesses, such as hypertension and ulcers, in environments where occupational noise may be a contributing factor (U.S. DOL, 1981a). The Mine Safety and Health Administration (MSHA) recently issued a new noise exposure regulation (MSHA, 1999) that increases the degree of protection from noise for mine employees.

Unfortunately, many occupations are not covered under OSHA or MSHA regulations. The National Institute for Occupational Safety and Health (NIOSH) estimates that many of the additional 15–20 million workers employed in unregulated nonmanufacturing industries (in particular, those in construction, agriculture, service, and trade industries) are likewise exposed to potentially hazardous noise.

Federal regulations related to occupational noise exposure have enhanced further interest and activities among audiologists and other professionals in the area of occupational hearing conservation. Concomitantly, public awareness of the effects of noise has grown in recent years, creating opportunities for professional participation.

Historically, ASHA has been involved with issues related to noise and its effects on humans (McLauchlin, 1978). ASHA's publications on this topic include ASHA Monograph Supplements numbers 1 (Kryter, 1950), 3 (Loring, 1954), and 28 (Suter, 1991), and ASHA Reports numbers 4 (Ward & Fricke, 1969) and 10 (Tobias, Jansen, & Ward, 1980). The Association sponsored a National Conference on Noise as a Public Health Hazard in 1969 and has actively supported all six of the International Congresses on Noise as a Public Health Problem. In 1964 and 1965, ASHA participated in the development of a “Guide for Training of Industrial Audiometric Technicians” (American Industrial Hygiene Association, 1966) as a member of the Inter-Society Committee on Audiometric Technician Training. This committee evolved in 1973 into the Council for Accreditation in Occupational Hearing Conservation (CAOHC), of which ASHA continues to be a component professional organization with two delegates to the Council. The guide was later replaced by the CAOHC Outline for Course Leading to Accreditation as an Occupational Hearing Conservationist Technician (CAOHC, 1993).

ASHA has been a leader and participant in many collaborative efforts in the legislative and political arena. In 1991, ASHA led a coalition to lobby OSHA for a stronger criterion for hearing loss recordability on the OSHA Form 200. This coalition consisted of representatives from ASHA, the National Hearing Conservation Association (NHCA), the American College of Occupational and Environmental Medicine (ACOEM), the American Academy of Otolaryngology-Head & Neck Surgery (AAO-HNS), and CAOHC. Also in 1991, ASHA convened a meeting at the request of Rep. Richard Durbin (D-IL) that was cosponsored by the Acoustical Society of America (ASA) and the AAO-HNS. Durbin distributed the proceedings of the meeting, “Combating Noise in the 90's: A National Strategy for the United States,” to members of Congress. In 1994, representatives of NHCA and ASHA met with OSHA Secretary Joseph Dear to discuss proposed reform of the OSHA noise standard. In 1996, ASHA led a coalition of professional associations that joined in providing oral and written comments to OSHA during a hearing concerning the recordability of occupational illness and injury (AIHA, 1996; Coalition to Preserve OSHA and NIOSH and Protect Workers' Hearing, 1996). In 1998, ASHA led a similar coalition of professional associations that provided input to MSHA during public hearings and requests for comments concerning the development of hearing conservation regulations for the mining industry prior to promulgation of the new MSHA regulation (MSHA, 1999).

With respect to nonoccupational hearing loss prevention efforts, ASHA has participated in the work of the Task Force on Hearing Conservation Education in the Schools, which is working to include coverage of hearing conservation in the elementary curriculum.

The foregoing historical account documents that for many years, audiologists have been actively involved in the prevention and assessment of NIHL and in assisting industry in the development of OHCPs, and that ASHA has displayed leadership in addressing these issues in the regulatory and public health arenas.

American Industrial Hygiene Association. (1966). Training requirements specified by the Inter-Society Committee on Audiometric Technician Training. American Industrial Hygiene Association Journal, 27, 303–304.

American Industrial Hygiene Association. (1996). Recommended criterion for recording occupational hearing loss on OSHA Form 300. American Industrial Hygiene Association Journal, 57(7), 661–662.

American Speech-Language-Hearing Association. (1991). Combating noise in the '90s: A national strategy for the United States. Rockville, MD: Author.

Coalition to Preserve OSHA and NIOSH and Protect Workers' Hearing. (1996). Comments in response to OSHA's notice of proposed rule, occupational injury and illness recording and reporting requirements (Comments submitted to OSHA docket No. R-02). Washington, DC.

Council for Accreditation in Occupational Hearing Conservation. (1993). CAOHC outline for course leading to accreditation as an occupational hearing conservation technician. Milwaukee, WI: Author.

Franks, J. R. (1999). Historical highlights in the development of national standards for occupational safety and health. The Hearing Review, 6(9), 18–27.

The effects of noise on man. (1950). Journal of Speech and Hearing Disorders((Monograph Suppl. 1)). <person-group person-group-type="editor">Kryter, K. D.</person-group>

Lipscomb, D. M. (Ed.). (1994). Hearing conservation in industry, schools, and the military. San Diego, CA: Singular.

Selected bibliography on the effects of high-intensity noise on man. (1954). Journal of Speech and Hearing Disorders((Monograph Suppl. 3)). <person-group person-group-type="editor">Loring, J. C. G.</person-group>

McLauchlin, R. M. (1978). Audiologists in the United States. In D. M. Lipscomb (Ed.), Noise and audiology (pp. 361–408). Baltimore, MD: University Park Press.

MSHA. (1999). Health Standards for Occupational Noise Exposure; Final Rule, 30 CFR Part 62, 64. Federal Register, 49458-49634, 49636-49637.

Occupational injury and illness recording and reporting requirements, 29 CFR Part 1904 and 1952. (2001, January 19). Federal Register, 66(13), 5916–6135.

Occupational injury and illness recording and reporting requirements, 29 CFR Part 1904. (2002, July 1). Federal Register, 67(126), 44037–44127.

Suter, A. H. (1991). Job performance in noise: A review [ASHA Monograph 28]. Rockville, MD: American Speech-Language-Hearing Association.

Suter, A. H. (1994). The development of federal standards and damage risk criteria (Chap. 5). In D. M. Lipscomb (Ed.), Hearing conservation in industry, schools, and the military. San Diego, CA: Singular Press.

Tobias, J. V., Jansen, G., & Ward, W. D. (Eds.). (1980). Proceedings of the Third International Congress on Noise as a Public Health Problem (ASHA Reports No. 10). Rockville, MD: American Speech-Language-Hearing Association.

U.S. Department of Labor. (1969). Occupational noise exposure regulation. Federal Register, 34, 7946.

U.S. Department of Labor. (1981a, January). Occupational noise exposure. hearing conservation amendment, Rule and Proposed Rule. Federal Register, 46, 4078–4181.

U.S. Department of Labor. (1981b, August). Occupational noise exposure. hearing conservation amendment, Rule and Proposed Rule. Federal Register, 46, 42622–42639.

U.S. Department of Labor, Bureau of Employment Security. (1965). Dictionary of occupational titles, 1, 30.

U.S. Department of Labor, Occupational and Health Administration. (1983). Occupational noise exposure, hearing conservation amendment. Federal Register, 48, 9738–9785.

Ward, W. D., & Fricke, J. E. (Eds.). (1969). Proceedings of the conference: Noise as a public health hazard (ASHA Reports No. 4). Washington, DC: American Speech-Language-Hearing Association.

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Appendix 2: Bibliography

A. Books

Alberti, P. W. (Ed.). (1982). Personal hearing protection in industry. New York: Raven Press.

American Industrial Hygiene Association. (1966). Training requirements specified by the Inter-Society Committee on Audiometric Technician Training. American Industrial Hygiene Association Journal, 27, 303–304.

American Speech-Language-Hearing Association. (1991). Combatting noise in the '90s: A national strategy for the United States. Rockville, MD: Author.

American Speech-Language-Hearing Association. (1994, October 24). Occupational hearing conservation: the current picture [Cassette Recording from Teleseminar held October 28, 1994]. Rockville, MD: Author.

Axelsson, A., Borchgrevink, H. B., Hamernik, R. P., Hellstrom, P. A., Henderson, D., & Salvi, R. J. (1996). Scientific basis of noise-induced hearing loss. New York: Thieme.

Berger, E. H., Royster, L. H., Royster, J. D., Driscoll, D. P., & Layne, M. A. (Eds.). (2000). The noise manual (5th ed.). Fairfax, VA: American Industrial Hygiene Association.

Berger, E. H., Ward, W. D., Morrill, J. C., & Royster, L. H. (Eds.). (1986). Noise and hearing conservation manual (4th ed.). Fairfax, VA: American Industrial Hygiene Association.

Committee on Hearing, Bioacoustics, and Biomechanics, National Research Council. (1993). Hazardous exposure to impulse noise. Washington, DC: National Academy Press.

Chasin, M. (1996). Musicians and the prevention of hearing loss. San Diego, CA: Singular.

Crocker, M. J. (Ed.). (1997). Encyclopedia of acoustics (Vol. 1–4). New York: John Wiley & Sons.

Dancer, A. L., Henderson, D., Salvi, R., & Hamernick, R P. (Eds.). (1992). Noise-induced hearing loss. St. Louis, MO: Mosby-Year Book.

Feldman, A. S., & Grimes, C. T. (1989). Hearing conservation in industry. Malabar, FL: Krieger.

Franks, J. R., Theman, C. L., & Sherris, C. (1994). The NIOSH compendium of hearing protection devices (Publication No. 95-105). Cincinnati, OH: U.S. Department of Health and Human Services.

Gasaway, D. C. (1985). Hearing conservation: A practical manual and guide. Englewood Cliffs, NJ: Prentice-Hall.

Kramer, M. B., & Armbruster, J. M. (1982). Forensic audiology. Baltimore, MD: University Park Press.

Lipscomb, D. M. (Ed.). (1978). Noise and audiology. Baltimore, MD: University Park Press.

Lipscomb, D. M. (Ed.). (1994). Hearing conservation in industry, schools, and the military. San Diego, CA: Singular.

Miller, M. H., & Silverman, C. A. (Eds.). (1984). Occupational hearing conservation. Englewood Cliffs, NJ: Prentice-Hall.

National Acoustic Laboratories. (1998). Attenuation and use of hearing protectors (8th ed.). New South Wales, Australia: National Acoustic Laboratories.

Royster, J. D., & Royster, L. H. (1990). Hearing conservation programs: Practical guidelines for success. Chelsea, MI: Lewis.

Suter, A. H. (1991). Job performance in noise: A review (ASHA Monograph 28). Rockville, MD: American Speech-Language-Hearing Association.

Suter, A. H., & Franks, J. R. (Eds.). (1990). A practical guide to effective hearing conservation programs in the workplace. Cincinnati, OH: NIOSH.

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B. Summary Articles, Bibliographies, and Chapters

Berger, E. H. (1979–1999). E-A-RLog Series of technical monographs on hearing and hearing protection (). Indianapolis, IN: E·A·R.

Berger, E. H., & Kladden, C. A. (1998). Noise and hearing conservation films and videotapes: Reviews and availability (E·A·R 82-10/HP). Indianapolis, IN: E·A·R/Aearo Company.

Embleton, T. F. W., Gibson-Wilde, B., Slama, J. G., Shaw, E. A. G., Gamba, R., Lazarus, H., Timar, P. L., Bellhouse, G., Ward, W. D., Roth, S. I., & Suter, A. H. (1997). Technical assessment of upper limits on noise in the workplace. Noise/News International, 5(4), 203–216.

Gelfand, S. A. (1997). The effects of noise and industrial audiology. In Essentials of audiology (pp. 487–525). New York: Thieme.

Miller, M. H. (1998). Hearing conservation in industry. Current Opinion in Otolaryngology & Head and Neck Surgery, 6, 352–357.

Mueller, H. G., & Hall, J. W. (1998). Hearing conservation, industrial audiology, and protecting the professional ear. In Audiologists' desk reference volume II: Audiologic management, rehabilitation, and terminology (pp. 659–763). San Diego, CA: Singular.

Royster, J. D. (1996). Noise-induced hearing loss. In J. L. Northern (Ed.), Hearing disorders (3rd ed., pp. 177–188). Boston, MA: Allyn & Bacon.

Royster, J. D. (1996). Occupational and forensic audiology. Current Opinion in Otolaryngology & Head and Neck Surgery, 4, 345–352.

Suter, A. H. (1992, January). Noise sources and effects—a new look Jan. 1992. Sound & vibration, 18–38.

Noise. In A. H. Suter (Ed.), J. Stellman (Ed.), Encyclopedia of occupational health and safety (4th ed., pp. 47.1–47.18). Geneva: International Labor Office.

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Appendix 3: Educational Materials

  • Crank It Down! is a curriculum designed for use with children from grades 2–5 which is available on a loan basis for the borrower to photocopy and then use. For information: National Hearing Conservation Association, 9101 East Kenyon Ave., Suite 3000, Denver, CO 80237.

  • Dangerous Decibels has developed museum exhibits and curricula for educating the public about noise-induced hearing loss and tinnitus. For information: Billy Martin, PhD, Director of Tinnitus Research, Oregon Hearing Research Center, Oregon Health Sciences University, email martinw@ohsu.edu, voice 503-494-7954.

  • Hearing Education and Awareness for Rockers (H.E.A.R.) is a nonprofit organization dedicated to the education of musicians and others about noise-induced hearing loss. For information: H.E.A.R., Kathy Peck, Executive Director, University of California-San Francisco Center on Deafness, 3333 California Street, Suite 10, San Francisco, CA 94118.

  • HIP Talk (Hearing Is Priceless) contains a videotape and educational curriculum for junior and high school students to stimulate student awareness of the dangers of exposure to loud volumes of sound over extended lengths of time. For information: House Ear Institute, 2100 West Third Street, Fifth Floor, Los Angeles, CA 90057.

  • I Love What I Hear! contains a videotape and educational curriculum for grades 3–8 designed to introduce children to the study of hearing science and to build awareness of the importance of hearing conservation. For information: National Institute on Deafness and Other Communication Disorders, NIDCD Clearinghouse, P.O. Box 37777, Washington, DC 20013-7777.

  • Know Noise contains a videotape, two cassette tapes, and educational curriculum in a contemporary format of rap music and interactive exercises to educate schools and youth groups about hearing health. For information: The Sight and Hearing Association, Carol Roney, 674 Transfer Road, St. Paul, MN 55114.

  • Operation BANG (Be Aware of Noise Generation) is a public awareness program developed to educate younger generations to be aware of noise and to educate the public about hearing conservation and the profession of audiology. Developed by the Air Force Audiology Association Public Relations Committee.

  • Operation SHHH contains an automated sound-operated stoplight as well as activity charts to teach children about noise. For information: Self Help for Hard of Hearing People, Inc., 7910 Woodmont Avenue, Suite 1200, Bethesda, MD 20814.

  • Stop That Noise! contains educational curriculum for grades 4–7 designed to teach young people how to protect and conserve their hearing. For information: League for the Hard of Hearing, 71 West 23rd Street, New York, NY 10010.

  • Wise Ears! is a coalition including the National Institute on Deafness and Other Communication Disorders, in partnership with the National Institute of Occupational Safety and Health, joined by national, regional, and local organizations, voluntaries, and state and local government agencies in a national campaign to prevent noise-induced hearing loss. For information: Office of Health Communication and Public Liaison, National Institute on Deafness and Other Communication Disorders, 31 Center Drive, MSC 2320, Bethesda, MD 20892-2320, voice: (301) 496-7243, fax: (301) 402-0018, email: ohcplmail-r@mail.nih.gov

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Index terms: hearing conservation

Reference this material as: American Speech-Language-Hearing Association. (2004). The audiologist's role in occupational hearing conservation and hearing loss prevention programs [Technical Report]. Available from www.asha.org/policy.

© Copyright 2004 American Speech-Language-Hearing Association. All rights reserved.

Disclaimer: The American Speech-Language-Hearing Association disclaims any liability to any party for the accuracy, completeness, or availability of these documents, or for any damages arising out of the use of the documents and any information they contain.

doi:10.1044/policy.TR2004-00153

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