Contemporary Technology 

for Hearing 

Conservation 

Audiometric 

By Richard Hi Danie/son, Monitoring Amanda Azman 

Ultimately, the most important product of a hearing 

conservation program is the prevention of hearing loss, not 

the amount of hearing protection that has been purchased or 

whether employees are attending their annual training sessions. 

Audiometric testing directly reveals whether hearing losses 

are actually occurring in a plant. With audiometric data, 

we can assess overall program effectiveness, alert workers 

of impending hearing loss, and reveal potential employer 

liabilities for compensable hearing loss. Without the ability 

to efficiently analyze audiometric data or produce effective 

reports, our programs become fruitless and unproductive. 

Consequently, ifaudiometric data are such vital end-products, 

then effective audiometric technologies serve as the prime 

architect and generator of these fundamental data. These 

technologies, consisting ofaudiometers, associated peripheral 

hardware, and database/reporting software, deserve our 

consideration.

If you are now conducting audiometric tests, you may 

have become so comfortable with your current equipment 

and recordkeeping system that it might seem like "this is the 

way things are supposed to be." However, could it be possible 

that one day your management might notify you that it's time 

to replace the audiometer, due to age or condition (or maybe 

due to an increase in your workload)? If that happens, where 

would you turn, and what criteria would you use, to shop for 

replacement instrumentation and database technology? The 

purpose of this article is to help you recognize some criteria 

of features currently available in audiometric equipment 

and audiometric database management software. Perhaps 

this information might help you plan for ways to enhance 

your program's efficiency and effectiveness (provided that 

budgetary constraints aren't exceeded). Even ifyou don't think 

that you're currently "shopping" for such technology, you may 

find it worthwhile to consider what's changed (and what has 

not changed) in this element of hearing loss prevention. 

The evolution of audiometric equipment to our current 

microprocessor-controlled audiometers has been relatively 

deliberate since "self-recording audiometers" were popular, 

several decades ago, in military and industrial hearing 

conservation programs. Of the various audiometers now 

marketed for use in hearing conservation programs, it's 

reasonable to assume that there's no perfect audiometer 

system for all scenarios. A small, in-plant HC program may 

require a basic audiometer, with fewer features than are needed 

by a service that uses mobile vans to support multiple companies 

in different cities. Basic manual audiometers can cost between 

$600 and $1,500, while microprocessor audiometers can cost 

approximately $1 ,500 to $5,500, depending on options ordered. 

But price shouldn't serve as the only criterion for audiometer 

equipmentselection.Achoice ofaudiometer andperipherals will 

be influenced by obvious issues like the number ofemployees 

needing tests, protocols used in the plant for audiometry and 

professional review of audiometric data, and capital operating 

resources. 

As shown inTable I (onpage 5), severalother considerations 

can be applied when choosing a new audiometer system. These 

considerations are intended to help spark questions that can 

be discussed with the equipment manufacturer or your 

equipment provider (e.g., someone affiliated with the National 

Association of Specialty Equipment Dealers, or NASED) 

about your needs. Since CAOHC doesn't intend to endorse 

any particular product or vendor, only general features will be 

addressed here, not specific manufacturers or models. 

NEW DEVELOPMENTS IN AUDIOMETRIC 

HARDWARE 

If your audiometric data will be saved electronically 

for analysis and reporting (see the discussion on audiometer 

software, later in this article), an interface with a computer 

becomes important. This link may be via a standard wired 

connection (e.g., RS-232, USB cable or Firewire), or even with 

wireless communication (up to 30 feet from the computer). 

In any case, consider how the data can be transferred to the 

computer, as well as how the audiometer can access data 

from previous tests in the database. If the level of activity 

requires testing more than one person simultaneously, it will 

be important that the audiometers can link to a controller and 
Table 1: Hardware considerations when purchasing a microprocessor audiometers. 

MICROPROCESSOR AUDIOMETER 

CONSIDERATION 

SPECIFIC QUESTIONS 

Interface to a computer Are direct connections to a computer and database software available? Can data be 

transferred electronically from (or to) your audiometer? 

If needed, how can audiometer test more than one person simultaneously? 

Is the method of data entry (keyboard or louch screen) appropriate for your situation? 

Interface to other audiometers 

Manual entry of data 

(e.g., /D, thresholds) 

Manual audiometry option How easily (intuitively) is manual audiometry performed? 

Audiogram storage Can audiograms and data be stored on the audiometer (if testing is done in remote areas)?

Recognition of errors 

(e.g., person responds too often) 

Does microprocessor audiometer recognize errors (and how many)? Does it alert the 

operator (and how)? 

With standard protocol, how long does it take to test typical person? 

Is there a talk-over mike? If so, is it mounted on audiometer's console or on headset? 

Duration of microprocessor-driven test 

Microphone 

Instructions Are recorded instructions available? If desired, are instructions available in languages other 

than English? 

Choice of test protocol Can you change protocols (e.g., first ear tested, include 8 kHz)? 

Price range Does the cost fit your business plan? 

Does audiometer hold calibration data for comparison with daily listening checks? Does 

audiometer recognize if earphones are different than the set used in calibration? 

Calibration of earphones 

Portability Can the unit be transported to other locations (if needed)? What does unit weigh? 

Printer capability Does system have an internal printer? Require an external printer? Allow use of both?

to the computer. Some audiometers allow entry ofidentifying 

information (e.g., employee name and lD number, previous 

baseline data, and responses to questions about histories) with 

full-size keyboard entries. while others use touch-sensitive 

screens or keypads for alpha-numeric entries. Ofcourse, it may 

not be feasible (or necessary) to always link the audiometer 

and computer. If the testing is done onsite at the plant, you 

may find it far more efficient to just transport the audiometer 

to the location and leave the computer in your office or clinic 

for later interconnections. lfthat's the case, your audiometer's 

internal memory can be a real asset. Audiometers can store 

audiometric data from a few dozen records to over a thousand 

audiograms. Depending on the software you choose, you 

can then have access to these records when the employees 

arrive for hearing testing. Later, the new audiometric records 

and data can be downloaded to the overall database at your 

convenience (e.g., when you've aITived home from your 

trip). Some units even operate on battery power, should your 

location be so remote. 

A microprocessor-driven audiometer's basic advantage 

has been that these units can be programmed to apply 

standard audiometric testing rules, without an operator 

(although NOT without oversight ofthe Occupational Hearing 

Conservationist, or OHC). For instance, when an employee 

depresses the response button when no tone is present or has an 

excessive numberoffalse positive responses, microprocessor 

audiometers can stop the test and alert the OHC ofthe problem, 

providing the option to reinstruct or abort the test. CAOHC's 

requirements to learn manual audiometry are based, in part, 

on the concept that such problem tests can be efficiently 

expedited onsite by switching to manual audiometric testing. 

Some audiometers will integrate the manually-determined 

threshold with thresholds from other frequencies, to complete 

the record. Moreover, if mUltiple tests are being conducted 

but don't all end at the same time, the audiometer operating 

system can be programmed to continue presentations of a test 

signal to those who finished quickly, until all have completed 

the test. Some microprocessor audiometers have a talk-over 

circuit so that the OHC can communicate with the tested 

employee (e.g., "Your test is completed. Do not remove 

your earphones, but sit and wait quietly"). Some models use 

digital signal processors to play pre-recorded sound files 

with instructions in languages (sometimes a dozen or more) 

other than English. This feature may be a real boost to the 

success of your program, if your employees do not possess 

strong English skills. Up to 25 customized test questions can 

be created and used with some audiometers. 

While it might seem intuitive that all audiometers use a 

standard audiometric (e .g., the Hughson-Westlake) technique, 

ask your vendor about how hearing thresholds are determined 

by a specific audiometer. This can affect the duration ofthe test 

and (more importantly) the validity ofthe hearing thresholds. 

Some audiometers allow changes in the default protocols 

(choice of OSHA, Canadian or other criteria), should the 

Professional Supervisor and OHC desire. 

As described in Table 1, you can also consider other 

audiometer options like set up and customization, calibration 
ofmore than one set ofearphones (and even recognition that an a license agreement that might allow only one database 

unrecognized set ofearphones has been used), portability (e.g., to be maintained. If needed, though, a more comprehensive 

weight and convenience factors), biological checks, printers combination of databases can be maintained (for instance, 

(built-in or peripheral), and audiogram backups. when a consultant is reviewing audiograms from multiple 

NEW DEVELOPMENTS IN AUDIOMETRIC sites). Your vendor may limit the number ofseparate locations 

DATABASE SOFTWARE that can be maintained, as well as the number of OHCs and 

An OHC who supports a small program, with only a reviewers who can be simultaneously using the software. 

few dozen noise-exposed employees, can quickly appreciate One clear advantage of an electronic database is how 

the of calculating Standard Threshold Shifts it maintains records of calibration data, OHC certifications, 

without support of automation 

(e.g., to track baselines and use 

age cOITections). Table 2 provides 

some specific considerations and 

questions related to audiometric 

database management software 

that can be applied to designing 

your own (should you choose 

to take on that task) or when 

shopping for a program that has 

been commercially prepared (and 

undergone troubleshooting to 

clear out bugs). While relatively 

few audiometer systems are being 

marketed (and once introduced, 

don't change dramatically for a 

few years), audiometer software 

technologies are guite diverse and 

can be customized. This variety 

is, logically, intended to meet 

specialized needs of the users. 

As shown in Table 2, some of 

the features of the software extend 

the capabilities of the audiometer 

(e.g., storage of audiograms) , 

while other features greatly exceed 

functionsavai lableonthe audiometer 

itself. Feneting out sources for 

audiometric software is a bit more 

complicated than contacting an 

audiometer equipment vendor, since 

software developers can range from 

those with proprietary links tied to a 

specific audiometer to independent 

vendors who aim to support multiple 

lines of audiometers. In some 

cases, the hearing conservation 

database software is of a larger 

occupational health care system. 

It's possible to locate software 

vendors via the National Hearing 

Conservation Association, your 

NASED point of contact, or (of 

course) Google searches. 

When considering software 

options, you may find that the 

conditions ofpurchase are linked to 

Table 2: Considerations when choosing audiometric database software 

AUDIOMETER SOFTWARE SPECIFIC QUESTIONS CONSIDERATION 

storage Is capacity adequate for audiogram database? 

Database platform Is proprietary? Windows-based or DOS? 

Modules Is software dedicated to hearing conservation or a module of larger 

occupational health system? 

How many users may use license and/or can use system 

simultaneouslv? 

Software licensing 

Is software's price fixed, negotiable, based on use of services, or based 

on amount of purchase? 

Initial purchase What products and services are provided with the initial cost and for 

how lonq? What happens after that? 

Price range 

Are audiometer checks required before any testing is done? Does 

system prompt user to perform check? 

Daily calibration or functional 

check 

Employee notification forms How does the software support employee notification of STS? Does the 

employee notification provide all OSHA-required elements? What 

additional information is also provided? 

Can reports be customized for user specifications? Can the user 

configure reports? Will the software company include report 

confjguration services with purchase, or will such service require 

additional fees? Are a variety of reports available? 

Reporting capabilities 

How are upgrades, maintenance and customer/technical support 

handled after initial coverage is over? If through a maintenance 

agreement, what is the cost? 

Maintenance fee 

Is there a charge for training in, and implementation of, the software? 

Anv other additional charQes? 

Other costs 

Is a professional review service available, or provided with the product . 

If available are such review services required? If review services are 

used, what is the turn-around time (to receive results)? 

Professional review 

Will the software generate your OSHA 300 log and automatically flag 

workers for inclusion? 

OSHA 300 Log 

Are baseline revisions handled using NHCA Guidelines or other 

criteria? Does software revise baseline automatically, or is revision 

made only after professional input? 

Baseline revision 

What criteria generate a medical referral? (AAO-HNS or other?) Do 

questions relate to physical symptoms (dizziness, fullness, tinnitus, 

pain)? How is a record cleared so that it doesn't continue to appear as 

needing a medical referral? 

Medical referral 

Does software include data fields to document other notes and findings 

that could affect hearing test results or compliance with the hearing 

conservation program (e.g., illness, non-use of HPDs, cerumen 

'mDactionl? 

Additional notes 

How does the software handle audiometric data "back-ups"? Are backups done automatically? How often? Is the source of backUps 

secure? 

Data back up 

How accessible is technical support? How will the vendor address your 

problem (e.g., by phone, remote connection, site visit etc.)? Is there a 

toll free number or email access to technical support? 

Technical support 

Written reports
 Can notification forms be printed in languages other than English?

(in non-English language)
 

Data conversion
 How are data from previous software handled? Is there a fee to convert 

data to work with the new software? 

Multimedia Is an interactive demonstration available to preview product?

If the application is web-based, how are security and accessibility 

issues handled? 

Web-based 

, 
daily functional check data, patient medical histories, noise _

exposure records, medical referrals, and other data for 

documentation and quality control. Currently, software 

options can offer (to some degree, more or less) an abundant 

amount of documentation, as shown in Table 2. Moreover, 

reports can be generated (either from an established set or 

customized) to indicate medical referrals, STS rates, trends, 

and reports of hearing loss among individuals, shops, or 

companies. As indicated in the table, you may find that 

the software company might charge an additional fee for 

customizing reports (or for allowing you to generate ad-hoc 

reports). You may also consider other software options (listed 

in Table 2) like capabilities to generate individual letters 

to employees (in languages other than English, if needed), 

flagging workers who have triggered an OSHA-recordable 

hearing loss or medical referral, or documentation of other 

notes (e.g., cerumen impaction) that might be relevant for 

the Professional Supervisor (PS) who reviews your data. 

Don't forget that the recommendation ofthe PS is required 

for problem audiograms, including decisions re baseline 

revision. Although the software might offer an "alert" 

re a need for baseline revision, the PS may override the 

revision alert if warranted. Don't trust the software to drive 

your hearing conservation program; use a knowledgeable 

PS (with the scope of practice outlined at www.caohc. 

org/professional_supervisor/scope php). 

Your PS will also be especially concerned about how your 

audiometer software can convert audiometric data (either by 

import or export functions), so be sure to coordinate your 

decision processes with your PS. While the effectiveness of 

your audiometric testing program benefits markedly from 

good recordkeeping, it's important to tailor your efforts to 

best use time and resources effectively. As Daniel 1. Boorstin 

once said, "Technology is so much fun but we can drown in 

our technology." Designers of audiometric equipment and 

audiometric database management technologies are aware 

of our need to be efficient, yet thorough. As you contemplate 

your future needs in this area, feel free to shop around, express 

your specific needs and coach the vendors who are earnestly 

seeking to develop technologies that contribute to our required 

jobs in hearing loss prevention. 

The opinions are neither those of the National Space 

Biomedical Research Institute nor of the National Institute for 

Occupational Safety and Health.