<PRE>
[Federal Register: November 14, 2000 (Volume 65, Number 220)]
[Rules and Regulations]               
[<strong>Page</strong> <strong>68411</strong>-<strong>68460</strong>]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14no00-17]                         
 
[[pp. <strong>68411</strong>-<strong>68460</strong>]] Ergonomics Program

[[Continued from <strong>page</strong> 68410]]

[[<strong>Page</strong> <strong>68411</strong>]]

    As mentioned above, OSHA received many comments (see, e.g., Exs. 
30-2116; 30-2809; 30-2825; 30-2847; 30-3258; 30-3035; 30-3001; 30-3033; 
30-3034; 30-3686; 30-4159; 30-4534; 30-4536; 30-4800; 30-4776; 30-4546; 
30-4547; 30-4548; 30-4549; 30-4562; 30-4627; 30-3332; 30-3259; 30-4801; 
30-3898; 30-4270; 30-4498; 31-242; 32-210-2; 500-71-86) stating that 
program evaluations should take place at least annually. These 
commenters generally argued, in the words of Greg Wyatt, an engineer 
who suffers from a repetitive stress injury and who offered comments as 
an individual, that ``the ergonomics program should be evaluated 
regularly (at least once a year) because it is easier and more cost 
effective to fix deficiencies early during the implementation phase'' 
(Ex. 30-3035). In a comment that pertains to all workplaces, the United 
Mineworkers of America agreed, ``Routine audits, no less frequently 
than once each year, should be performed of the entire workplace and 
problem areas reported to the appropriate company representative for 
immediate action'' (Ex. 500-71-86).
    The need for evaluations at a minimum frequency of less than 3 
years was addressed by several commenters (see, e.g., Exs. 30-2116; 30-
2809; 30-2825; 30-2847; 30-3258; 30-3035; 30-3001; 30-3033; 30-3034; 
30-3686; 30-4159; 30-4534; 30-4536; 30-4800; 30-4776; 30-4546; 30-4547; 
30-4548; 30-4549; 30-4562; 30-4627; 30-3332; 30-3259; 30-4801; 30-3898; 
30-4270; 30-4498; 32-210-2; 32-111-4; 32-229; 30-4247), who pointed out 
that workplace changes that adversely affect the functioning of a 
particular element of the program or of the program as a whole can 
occur in the interval between periodic evaluations (or ``regularly 
scheduled'' evaluations). For example, the United Steelworkers of 
America (UOWA) agreed that employers should evaluate their ergonomics 
programs at least every 3 years but asked OSHA to include in the final 
rule requirements that would trigger evaluations at more frequent 
intervals as well. ``OSHA should provide additional specific 
requirements for the employer to respond to concerns raised by workers 
between evaluations. For example, employers should review health and 
safety committee minutes to determine if ergonomic concerns were 
identified, [and] then they should verify that those concerns have been 
promptly addressed or address them at that time'' (Ex. 32-111-4).
    From a somewhat different perspective, Organization Resources 
Counselors, Inc. (ORC) (Ex. 30-3813) and Edison Electric Institute 
(EEI) (Ex. 500-33) asked that the standard's language be changed to 
reflect their belief that a requirement to evaluate an ergonomics 
program both periodically and every three years was excessive. Both 
commenters agreed that the employer was in the best position to 
determine how often the ergonomics program at a particular worksite 
needs to be evaluated to ensure its effectiveness. However, in ORC's 
words, ``it is not reasonable that the standard should require both 
periodic evaluation as well as an evaluation every three years.'' These 
commenters urged OSHA to require employers to evaluate their ergonomics 
programs periodically, ``and/or'' at least every 3 years.
    Another rulemaking participant, the National Soft Drink Association 
(NSDA) (Ex. 30-368) questioned whether performance of a program 
evaluation every 3 years also would satisfy the proposed requirement 
for periodic evaluations. Because, NSDA believes that the two 
provisions are duplicative, it recommended that the term ``periodic'' 
be eliminated. The Dow Chemical Company (Ex. 30-3765) also opposed the 
``at least every 3 years'' language, on the grounds that industry 
should be able to decide if and when periodic evaluations should be 
carried out but agreed that periodic reviews are necessary: * * * 
review on a periodic basis is necessary, especially * * * for dynamic 
workplaces with continuous turnover, process changes, etc.'' The 
National Telecommunications Safety Panel (Ex. 30-3745) agreed, saying 
the proposed rule's prescribed frequency presented particular problems 
for them because of their members' geographic sweep and rapidly 
changing workplaces and that [determining] ``program evaluation 
frequency * * * [should be] the sole responsibility of the employer.''
    A few commenters (see, e.g., Exs. 30-4713 and 30-4046) stated that 
the proposal's requirements for program evaluation were excessive: ``* 
* * a complete evaluation, as required by the rule, cannot be 
realistically performed `periodically,' as that term is defined.''
    A number of commenters who have themselves experienced MSDs (see, 
e.g., Exs. 30-2116; 30-2809; 30-2825; 30-2847; 30-3258; 30-3035; 30-
3001; 30-3033; 30-3034; 30-3686; 30-4159; 30-4534; 30-4536; 30-4800; 
30-4776; 30-4546; 30-4547; 30-4548; 30-4549; 30-4562; 30-4627; 30-3332; 
30-3259; 30-4801; 30-3898; 30-4270; 30-4498) also urged OSHA to require 
in the final rule that ``every time an employee reports persistent MSD 
symptoms or an MSD injury, Job Hazard Analysis and Control must be 
performed, and the ergonomics program must be re-evaluated.'' In the 
view of these commenters, every report of an MSD injury or persistent 
MSD symptom points to a deficiency in the ergonomics program that must 
be evaluated and corrected. OSHA agrees with these commenters that 
significant changes in workplace conditions, such as the introduction 
of a new process; changes in management or supervisory personnel, 
procedures, or policies; or changes in the form or intensity of 
employee involvement, can affect the functioning of the program 
substantially and thus may necessitate an evaluation of particular 
program elements or of the program as a whole.
    However, the Agency has chosen not to shorten the minimum interval 
between program evaluations to once a year from every three years 
because such a requirement would prove to be too burdensome if imposed 
on all of industry. Such a frequency would deprive employers of the 
flexibility which was OSHA's goal in drafting the program evaluation 
requirements, given the diversity of workplaces covered by this rule.
    OSHA also is not persuaded that it would be appropriate to require 
employers to evaluate their programs every time an MSD incident occurs 
or an ergonomic concern is expressed, as some commenters urged the 
Agency to do. Such a requirement would precipitate constant evaluations 
for employers with large workforces, where the incidence of MSD 
injuries is often high. OSHA does not expect that the program mandated 
by the standard will eliminate MDSs in the workplaces covered by the 
standard; indeed, as the discussion in Section VI of this preamble 
makes clear, OSHA is projecting that, on average, the standard will 
prevent about 50% of MSDs in such workplaces. Further, the Agency 
believes that employee concerns about ergonomics will be addressed 
regularly as a result of the standard's requirements for prompt 
responses to employee concerns and regular employer/employee 
communications about workers' concerns.
    After a review of the evidence in the record on the frequency of 
program evaluations, the final rule requires them when there is reason 
to believe that the program is not functioning properly, when changes 
have occurred that may have increased employee exposure to MSD hazards, 
and at least once every three years. The final rule's requirements are 
essentially similar to those proposed, although they are somewhat more 
specific. OSHA's reasons for retaining provisions for program 
evaluation that require such

[[<strong>Page</strong> 68412]]

evaluations at least once every 3 years and at other times if workplace 
conditions warrant them, are: (1) the diversity of conditions in the 
workplaces covered by the rule demands the combination of specificity 
and flexibility provided by the provisions in paragraphs (u)(1) and (2) 
all programs need to be evaluated at least once every 3 years to ensure 
that they are functioning optimally and meeting the needs of the 
organization over time.

Paragraph (u)(2)--Steps Involved in Program Evaluation

    In the proposed section titled ``What must I do to evaluate my 
ergonomics program?'', the proposed rule stated that program evaluation 
goes beyond a mere inspection or audit of problem jobs. The final rule, 
at paragraphs (u)(2)(i), (ii), (iii) and (iv ), contains similar 
requirements. For example, the proposed rule would have required 
employers to consult with employees in problem jobs to assess their 
views about program effectiveness and identify program deficiencies, 
paragraph (u)(2)(i) of the final rule requires employers to consult 
with employees, ``or a representative sample of them,'' about program 
effectiveness and any problems with the program. Paragraph (u)(2)(iii) 
requires employers to evaluate the elements of a program to ensure it 
is functioning effectively; this language is essentially unchanged 
since the proposal. The proposal would have required employers to carry 
out evaluations to ensure that the program was ``eliminating or 
materially reducing'' MSD hazards, while the final rule at paragraph 
(u)(2)(iii) requires the employer to assess whether MSD hazards are 
being identified and ``addressed.'' The final rule adds, at paragraph 
(u)(2)(iv), a requirement that employers use the evaluation as an 
opportunity to assess whether the program as a whole is achieving 
positive results. OSHA includes examples of measures of effectiveness, 
such as reductions in the number or severity of MSDs, increases in the 
number of jobs in which ergonomic hazards have been controlled, 
reductions in the number of jobs posing MSD hazards to employees, or 
any other measure that demonstrates program effectiveness.
    An adequate evaluation asks questions of employers at all levels of 
the organization to determine whether the required ergonomics program 
elements have been adequately implemented and whether they are 
integrated into a system that effectively addresses MSDs and MSD 
hazards. Examples of questions an evaluation is designed to explore 
are:

--Has management effectively demonstrated its leadership?
--Are employees actively participating in the ergonomics program?
--Is there an effective system for the identification of MSDs and MSD 
hazards?
--Are identified hazards being controlled?
--Is the training program providing employees with the information they 
need to actively participate in the ergonomics program?
--Are employees using the reporting system?
--Are employees reluctant to report MSDs or MSD hazards because they 
receive mixed signals from their supervisors or managers about the 
importance of such reporting?
--Is prompt and effective MSD management available for employees with 
MSDs?
    OSHA finds that these questions, which were included in the 
proposal, continue to be appropriate points for program evaluations to 
address. The comments OSHA received on the proposed requirements for 
conducting evaluations addressed the following topics: the vagueness of 
the proposed terms used; the inclusion of core elements in the program 
required by the standard and in the standard's requirements for 
evaluation; the need for OSHA to specify measures of effectiveness for 
employers to rely on; the statement in the basic obligation section of 
the proposed rule that programs should be evaluated to ensure that they 
are in compliance with the standard itself; who should carry out 
program evaluations; the records to be reviewed in a program 
evaluation; and the extent of the recordkeeping required by this 
provision of the standard. The comments OSHA received on each of these 
topics are discussed below.
    Vagueness of the rule's terminology: The Center for Office 
Technology (COT) complained that some of the terms used in the context 
of the proposed evaluation section were vague and ``subjective'' (Ex. 
25-710). Specifically, COT pointed to the proposed requirement that 
evaluations be conducted ``as often as necessary'' (defined in the 
proposal as ``periodically'') as an example of the vagueness of the 
proposal's language. COT stated, ``* * * training and program 
evaluation must be conducted ``as often as necessary'' and the program 
must be ``appropriate'' to workplace conditions. How will compliance 
with these vague, undefined and subjective requirements be assessed?''
    Inclusion of core elements in the program: The Forum for a 
Responsible Ergonomics Standard (Exs. 32-351-1 and 30-3845) and others 
(Exs. 30-574; 30-2773; 500-33; 30-4040) were critical of the proposed 
Ergonomics Program standard's requirement that employers include in 
their programs, and evaluate, six mandatory core elements. By mandating 
that ergonomics programs have a certain form, i.e., have specific 
elements, instead of requiring only that the program be effective, OSHA 
was, according to the Forum, ``elevating form over function, divorcing 
its program from [what should be] the goal of achieving reduced MSD 
injuries and focusing instead on ensuring that programs fit a 
bureaucratic mold that is administratively simple.'' In other words, 
the Forum believes that the effectiveness of an ergonomics program 
should be the sole measure of its success in any evaluation. The Forum 
stated that the proposed approach to program evaluation could lead to 
``the perverse possibility'' of an employer with a program that 
successfully reduces MSDs being cited for a violation of the standard 
merely because the program failed to include a required program 
element.
    Another commenter (Ex. 31-353) questioned how effective a program 
evaluation could be unless the rule required the effectiveness of each 
of the individual Ergonomic Program elements to be evaluated. ``Without 
determining the effectiveness of all the aspects of the program, an 
employer is wasting time and money, and effort.'' Similarly, the 
Department of Defense (Tr. 9085-9086) stated, ``If the evaluation is 
focused on the presence and function or process elements of the program 
then the standard should clarify the essential evaluation points for 
each program element.''
    Compliance as a measure of effectiveness: The Dow Chemical Company 
(Exs. 30-3765 and 32-77-2) asked, ``Is the point of program evaluation 
to evaluate compliance with the standard or the program's 
`effectiveness'? Or both?'' Dow's comment referred to a statement in 
the basic obligation section of the proposed rule to the effect that 
the program was to be evaluated to ensure its compliance with the 
standard. According to Dow, ``If OSHA maintains the requirement to 
evaluate `effectiveness' of a program, then it should indicate the 
method an employer can use for measuring `effectiveness.' '' A program 
may have all of the required elements and thus be in compliance with 
the rule, but not address all potential MSDs'' (Ex. 30-3765). The 
Association of Energy

[[<strong>Page</strong> 68413]]

Servicing Contractors (Tr. 15624) and others (Ex. 30-3839) agreed with 
Dow about the need for measurable criteria with which to gauge 
compliance with the standard.
    Also commenting on this point was the Honorable Senator Christopher 
S. Bond, Chairman of the United State Senate Committee on Small 
Business, who submitted a study (Ex. 30-4334-4) carried out by the 
Regulatory Studies Program of Mercatus Center at George Mason 
University, entitled, ``Over Stressing Business: OSHA and Ergonomics.'' 
The study included the following statement: ``The draft rule requires 
employers to evaluate their ergonomics program according to both 
activity and outcome measures. Yet in the case of MSDs, neither 
activity nor outcome measures are likely to reflect program 
effectiveness.''
    The final rule does not require employers to evaluate their 
programs for compliance with the standard, as proposed, because this 
statement confused commenters and is unnecessary. The final rule's 
requirements (paragraphs (u)(1)(ii) and (iii)) that employers 
``evaluate the elements of the program to ensure they are functioning 
effectively'' and ``assess whether the program is achieving results'' 
will essentially ensure compliance with the standard and eliminate the 
confusion caused by the proposed statement. Further, as the Dow 
Chemical Company pointed out, programs may be effective even if they do 
not contain every sub-element of the OSHA standard; this is certainly 
the case with grand fathered programs that were put in place well 
before OSHA's standard was promulgated (Exs. 30-3765 and 32-77-2).
    Measures of program effectiveness: Many commenters asked OSHA to 
identify measures of program effectiveness that the Agency believes are 
appropriate. For example, the Dow Chemical Company stated, ``If OSHA 
maintains the requirement to evaluate `effectiveness' of a program, 
then it should indicate the method an employer can use for measuring 
`effectiveness'. A program may have all the required elements and thus 
be in compliance with the rule, but not address all potential MSDs'' 
(Ex. 30-3765). The Oregon Building Industry Association (Ex. 30-562) 
and others (Exs. 30-368, 30-541, 30-627, 30-1697, 30-1717, 30-1355, 30-
1545, 30-3783; 31-334: 32-210-2) raised the same issue, and the Oregon 
Association also asked, ``Would the occurrence of an injury allow the 
OSHA inspector to automatically qualify the program as not effective?'' 
(Ex. 30-562).
    Organization Resources Counselors, Inc. (ORC) (Ex. 30-3813) voiced 
a somewhat different concern regarding the need for measures of 
effectiveness. ``OSHA expresses particular concern in the preamble that 
there is a need to assure that a demonstration of effectiveness does 
not mask under reporting of MSDs,'' they wrote. ORC agreed that this 
was a real concern and suggested that employers should be required to 
provide evidence that there is an effective early reporting mechanism 
in place as a part of their demonstration of program effectiveness. In 
response to the views of commenters, OSHA notes that the final rule 
identifies a number of measures of effectiveness, including reductions 
in the number or severity of MSDs, increases in the number of jobs in 
which ergonomic hazards have been controlled, reductions in the number 
of jobs posing MSD hazards to employees, or any other demonstrably 
appropriate measure of effectiveness, that OSHA believes are indicative 
of program effectiveness. This list of measures is not exhaustive; it 
is meant to be illustrative only. OSHA is aware that employers with 
successful programs use other measures, such as reductions in workers' 
compensation costs, increases in the number of early reports of MSD 
signs and symptoms, and increases in product quality, to evaluate the 
effectiveness of their ergonomics programs (DOD Tr. 3296-3297; OR Ex. 
32-78-1 p.22; AFL-CIO Ex. 32-339-1-29; Library of Congress Ex. 32-339-
1-33 p.143; Paper, Allied-Industrial, Chemical & Energy Workers 
International Union Local 1202 (PACE) Tr.11206; International Paper Ex. 
32-61).
    As one rulemaking participant, Organization Resources Counselors 
(ORC) (Tr. 4147) stated during testimony about the proposed rule, ''* * 
* there are many different ways that companies use to evaluate 
effectiveness. While they might all have common elements. . .they apply 
those elements in very different ways, depending on the circumstances, 
the nature of the work, the employees, and the nature of the 
workplace.'' In addition, OSHA does not believe that the ``occurrence 
of an injury'' automatically qualifies a program as ``ineffective,'' in 
the words of the Oregon Building Industry Association (Ex. 30-562). 
OSHA recognizes that, especially in large workplaces in industries with 
many problem jobs, MSDs may continue to occur. The final rule takes a 
comprehensive view of program effectiveness and emphasizes the 
importance of the essential elements of the program and their proper 
functioning. In response to ORC's comment about the importance of 
ensuring that early reporting is present, OSHA agrees that such 
reporting is essential to program effectiveness and has accordingly 
built several mechanisms that will ensure early reporting'work 
restriction protection, multiple HCP review, hazard information and 
reporting'into the final rule.
    Who should conduct program evaluations?: The preamble to the 
proposal stated that program evaluations may be conducted by those 
responsible for carrying out the employer's program, but also noted 
that evaluations performed by persons who are not involved in the day-
to-day operation of the program are often even more valuable because 
these individuals bring a fresh perspective to the task. They often can 
identify program weaknesses that those routinely involved in program 
implementation may fail to see (64 FR 65858-65859). OSHA received a 
number of comments addressing who should perform the required 
evaluations (Exs. 30-2809; 30-115; 30-2387; 30-3826; 32-339-1; 601-x-
1587-2). One commenter cautioned that special care must be taken to 
ensure continuity within the program when outside entities perform 
successive program evaluations (Ex. 30-2809). This commenter stated, 
``It is important to keep records from every evaluation of the 
ergonomics program so that mistakes are not repeated * * * if a 
different company performs the evaluation, lessons learned from the 
previous evaluation may not be recorded * * * It is also important to 
ensure that all ``action items'' (issues brought up during previous 
evaluations) are resolved and not ignored.''
    The American Federation of Government Employees (AFGE) (Ex. 30-115) 
suggested that OSHA or some neutral third party was the appropriate 
entity for evaluating the ergonomics program because ``management 
should not have carte blanche to evaluate their own program.'' 
Similarly, the American Society of Safety Engineers (ASSE) (Ex. 601-x-
1587-2) commented that the level of expertise needed to perform program 
evaluation/third party audits under this standard is outside that which 
many organizations are able to provide. Therefore, ``in order to meet 
the expected need of consultation services, OSHA should consider 
reviewing a system for voluntary third party audit and evaluations, and 
work with accredited private sector professional certification bodies, 
both public and private recognized registries,

[[<strong>Page</strong> 68414]]

and membership organizations to ensure that consultants have an 
acceptable level of competence.''
    The American Association of Occupational Health Nurses (AAOHN) (Ex. 
30-2387) cautioned OSHA about the need to protect employee privacy 
during the collection and review of program records for evaluation 
purposes. The AAOHN pointed out that ``individuals who are not part of 
the day to day operation of the program can bring a fresh perspective, 
however in any evaluation, the employer should ensure that employees' 
privacy is protected.'' For example, the AAOHN noted that a co-worker 
brought in to evaluate a program must understand the need for 
confidentiality concerning her or his co-worker's personal health 
information, if such information is part of the program evaluation. 
OSHA agrees with the AAOHN that the privacy of employee medical and 
exposure records must be protected at all times, including during a 
program evaluation. These records are required to be handled at all 
times in accordance with 29 CFR 1910.1020, OSHA's Access to Employee 
Exposure and Medical Records standard.
    In response to the views of these commenters, OSHA notes that the 
proposed rule did not specify who was to perform the required program 
evaluations; the final rule also does not limit the employer's choice 
of program evaluators. OSHA is aware that employers with effective 
programs rely on different individuals, both from within and outside 
their organizations, to perform this function and that the results of 
doing so are often excellent (see, e.g., Exs. 32-339-1-53, 601-X-1711). 
Some programs, such as the one at General Motors, rely on trained 
employees in a Joint Ergonomics Team, consisting of union and 
management members, to conduct program evaluations (Ex. 32-339-1-53), 
while other companies, such as Halliburton, Inc. (Ex. 601-X-1711) rely 
on a Board Certified Professional Ergonomist or other outside expert or 
organization to carry out their program evaluation. OSHA does not agree 
either with those commenters who argued that employers are not choosing 
appropriate and qualified program evaluators or that the Agency should 
narrow the employer's discretion in this regard. OSHA remains convinced 
that different approaches are appropriate in different workplaces and 
that employers are best suited to decide who should conduct the 
required evaluations. The final rule, therefore, leaves the selection 
of evaluators to the employer.
    Records review in the context of program evaluation: OSHA 
recognizes in the final rule, as it did in the preamble to the proposed 
rule (64 FR 65859), that the extent of the evaluation called for by the 
rule will vary from one workplace to another, based on the 
characteristics and complexities of the work environment. However, the 
basic tools of evaluation remain the same from workplace to workplace, 
even though their application may vary. These tools, which are basic to 
the evaluation of any safety and health program, include:

--Review of pertinent records, such as those related to MSDs and MSD 
hazards;
--Consultations with affected employees (including managers, 
supervisors, and employees) regarding the ergonomics program and its 
problems (if any); and
--Reviews of MSD hazards and problem jobs.

    Examples of the records that are often included in such reviews 
include the following:

--The OSHA 200 log (if the employer is required to keep a log);
--Reports of workers' compensation claims related to MSDs;
--Reports of job hazard analyses and identification of MSD hazards;
--Employee reports to management of MSDs or persistent MSD signs or 
symptoms;
--Insurance company reports and audits about ergonomic risk factors or 
MSD hazards; and
--Reports about MSD hazards from any ergonomic consultants engaged by 
the employer.

    Some employers, especially owners of very small businesses, may 
have few of these records and will, therefore have to rely on other, 
less formal, methods to assess effectiveness. Small employers generally 
place more emphasis on employee interviews and such approaches as 
surveys of MSD hazards and problem jobs when they perform ergonomics 
program evaluations. Records reviews can yield valuable information on 
the effectiveness of an ergonomics program when comparisons are made 
from year to year and trends are identified. For example, if an 
employer compares the list of MSD hazards identified during consecutive 
program evaluations and finds that the number of hazards has decreased 
over time, the employer may conclude that the program's job hazard 
analysis and control activities have been effective. Similarly, a 
reduction in the number of MSDs from year to year suggests that the 
program may be effective, although numbers alone sometimes can be 
misleading. However, program evaluation also must consider the accuracy 
and reliability of the records under review. For example, it is 
essential to be sure that the identified trends are real and not the 
product of under reporting, loss of interest in the program, or loss of 
attention to detail. For example, a downward trend in the number of 
MSDs or MSD hazards reported may indicate that employees are being 
discouraged from reporting or that the employees performing job hazard 
analysis and control are not doing an effective job because they are 
not adequately trained to do so.
    OSHA received a variety of comments about records review in the 
context of program evaluation (Exs. 30-3765, 30-276; 30-546; 30-2846; 
30-1726). For example, the Dow Chemical Company argued that the 
proposed requirement that employers evaluate different elements of the 
program would require them to gather records to support this effort and 
would thus impose an undue burden on certain employers. Dow argued, 
``depending on the size and makeup of the workplace, a review of all 
the proposed records by each workgroup would add undue burden on each 
group'' (Ex. 30-3765).
    Texas A and M University (Ex. 30-276) also found the records review 
associated with program evaluation potentially burdensome. ``Record 
keeping is not value-added for the employer or employees. It primarily 
benefits the regulatory overseer.'' ElectriCities of North Carolina 
Inc. (Ex. 30-546) agreed: ``[These sections] speak of compulsory Record 
keeping above and beyond the OSHA 200 log of recordable work place 
injuries and illnesses * * *''. The Manufactured Housing Institute (Ex. 
30-2846) noted that ``Small business is already overwhelmed with 
paperwork requirements and OSHA should avoid adding to that burden.''
    The University of Wisconsin Extension (Ex. 30-1726) asked OSHA to 
require that all MSD reporting forms be retained by employers for 
eventual program review. ``If a standard reporting form is required for 
all employees to report MSD problems, signs and symptoms, these forms 
should be retained and made part of the program review, to follow up 
each form filed during the program evaluation period.''
    In response to these concerns about the recordkeeping burden 
associated with program evaluation records review, OSHA notes that the 
final rule does not mandate that employers review specific records when 
conducting their evaluations. In fact, the final rule does

[[<strong>Page</strong> 68415]]

not mandate records review or require the development of new records of 
any kind. This preamble discussion on records review simply recognizes 
that reviewing records already maintained by the employer for other 
purposes is one way of getting the information needed to evaluate a 
program.
    The Agency believes that employers are best able to determine which 
records in their workplace will provide the most valuable information 
for evaluation purposes. For example, in a very small firm that is not 
required to keep the OSHA 200 Log, the only records available for 
review may be employee reports of MSD incidents, workers' compensation 
claim information, and records of Quick Fix controls implemented; some 
workplaces may not even have these records. In most workplaces, 
however, employers will wish to review a variety of records to identify 
trends, evaluate the functioning of each program element, and assess 
the overall performance of the program. OSHA's approach is consistent 
with that taken by a number of employers who conduct evaluations of 
their ergonomics programs, in that it allows employers the latitude to 
decide how best to conduct evaluations of their workplaces. The United 
Technologies Corp. (Ex. 31-334) agrees that such flexibility is 
important: ``It is important to encourage creativity and innovation on 
the part of employers in meeting the requirements * * *''. This 
flexibility also means, of course, that employers such as The 
University of Wisconsin Extension (Ex. 30-1726) who wish to develop 
standardized MSD reporting forms to use for evaluation and other 
purposes are free to do so.
    The proposal contained a requirement that program evaluation 
include consultations with employees, and the final rule also includes 
such a requirement. Affected front-line employees (or a sample of 
them), and their supervisors and managers, must be included in this 
process. Consultations with employees elicit information on how well 
the ergonomics program has been communicated to the people who rely on 
it the most.
    Paragraph (u)(2)(ii) of the final rule requires employers to 
evaluate the elements of their ergonomics programs to ensure that each 
of the elements is working properly. If employees cannot explain what 
MSD hazards they are exposed to in the course of their work, do not 
know what steps their employer is taking to eliminate or control these 
hazards, are unclear about the procedures they should follow to protect 
themselves from these hazards, or do not understand how to report MSDs 
or MSD hazards, the hazard information and reporting and training 
components of the program are not working. If a supervisor is unclear 
about how to reinforce proper work practices, the management leadership 
and training components of the program are both likely to need 
improvement. Similarly, if managers are not aware of the MSDs and MSD 
hazards employees are reporting and what corrective actions are being 
taken, the management leadership and training components of the 
ergonomics program should be improved. Because interviews allow the 
program evaluator to assess how the elements individually and the 
program as a whole is actually working, there is no substitute for 
direct input from employees in the evaluation process.
    Program evaluation also must include an assessment of MSD hazards 
and the extent to which they are being addressed (paragraph 
(u)(1)(iii)). This assessment is concerned not only with identifying 
MSD hazards but with identifying how well the ergonomic program is 
addressing them. If the program evaluation identifies jobs that have 
not been analyzed but exceed the Action Level, the job hazard analysis 
component of the program needs to be improved. In addition, if jobs 
with previously identified MSD hazards have not been corrected or 
prioritized for correction, the evaluator may conclude that the job 
hazard control component of the program is not effective. Likewise, if 
an MSD hazard is identified and controlled in a problem job in one part 
of the facility but the same job has not been controlled in another 
part of the facility, several program components may need attention: 
the management leadership component, which may have failed to 
coordinate and disseminate MSD hazard information throughout the 
facility, the training component, which may have failed to provide the 
employees performing the job hazard analyses with adequate training, 
and the control component, which may have failed to prioritize jobs 
appropriately for control.
    Paragraph (u)(1) (i)-(iv) establishes the steps employers must 
follow to evaluate the effectiveness of their ergonomics programs. It 
answers the question, ``What must I do to make sure my ergonomics 
program is effective?'' This requirement describes the minimal 
evaluation procedures necessary to assess whether or not an ergonomics 
program is working as intended. Paragraph (u)(1) of the final rules 
reads as follows:

    (1) You must evaluate your ergonomics program at least every 
three years as follows:
    (i) Consult with your employees in the program, or a sample of 
those employees, and their representatives about the effectiveness 
of the program and any problems with the program;
    (ii) Review the elements of the program to ensure they are 
functioning effectively;
    (iii) Determine whether MSD hazards are being identified and 
addressed; and
    (iv) Determine whether the program as a whole is achieving 
positive results, as demonstrated by such indicators as reductions 
in the number and severity of MSDs, increases in the number of 
problem jobs in which MSD hazards have been controlled, reductions 
in the number of jobs posing MSD hazards to employees, or any other 
measure that demonstrates program effectiveness.

    Paragraph (u)(1)(i) of the final rules requires employers to 
``consult with your employees in the program, or a sample of those 
employees, and their representatives about the effectiveness of the 
program and any problems with the program.'' Employee participation in 
the ergonomics program is critical for success, and the involvement of 
employees in program evaluation is just one more way that employees can 
take an active role in the program. The requirement that employers 
consult with employees regarding program evaluation is not unique to 
the final Ergonomics Program standard. OSHA recently promulgated a 
similar provision in the Respiratory Protection final rule (29 CFR 
1910.134).
    Employees in jobs that have been identified as problem jobs are in 
the best position to judge whether or not job hazard analysis and 
control measures are effectively reducing or eliminating MSD hazards. 
Perhaps even more importantly, these employees will be most 
knowledgeable about whether the implemented controls have introduced 
new, unintended MSD hazards to the job. By consulting with employees, 
employers also can have direct feedback on the effectiveness of other 
ergonomics program elements, such as opportunities for employee 
participation, hazard information and reporting, and training. OSHA is 
aware that employers sometimes act in good faith to implement 
ergonomics program elements, but that the actual result experienced by 
employees can differ markedly from the intention. Thus, by checking 
directly with their employees, employers can be sure that their 
ergonomics program resources are being effectively invested.
    Two rulemaking participants commented that the proposed provision 
on employee consultation did not require consultations with anyone 
other than employees in problem jobs or allow the employer to select a 
subset of

[[<strong>Page</strong> 68416]]

employees with whom to consult. The Department of Defense (Ex. 30-3826) 
commented that, for some employers, such as large companies, branches 
of the military, etc., the requirement to consult with employees could 
be interpreted to mean consultation with tens of thousands of 
employees. As a result, DOD requested that the requirement be changed 
in the final rule to allow for representative sampling of employees. In 
addition, both the DOD (Ex. 30-3826) and the AFL-CIO (Exs. 32-339-1; 
500-218) commented that OSHA had neglected to include employee 
representatives in the proposed consultation process. The AFL-CIO 
suggested (Ex. 32-339-1) that this provision of the final rule ``should 
be modified to provide for consultation with the employee 
representative, in addition to employees in problem jobs. This 
modification is consistent with the requirement of [the proposed 
employee participation provision] which calls for both employees and 
employee representatives to be involved in all aspects of the 
program.''
    After reviewing the record on these points, the Agency has revised 
paragraph (u)(1)(i) of the final rule to reflect the concerns of larger 
employers and to allow them to consult with employees in the program, 
or ``a sample of those employees'' about the effectiveness of the 
program and any problems with it. In addition, the final rule states 
clearly that designated employee representatives are to be involved in 
the consultation process (paragraph (u)(1)(i)). Further, employers are, 
of course, free to involve other employees in the consultation process 
if they wish to do so; however, OSHA is not requiring that employees 
other than those in problem jobs be consulted as part of the evaluation 
process.
    Another concern raised by the Dow Chemical Corp. (Ex. 30-3765) was 
its interpretation that OSHA was attempting in the preamble for this 
proposed section to mandate the questions employers must ask in 
conducting an evaluation: ``Dow does not believe that OSHA should 
mandate the specific questions each employer must ask employees during 
this review, which it seemingly tries to do in the preamble at <strong>page</strong> 
65858.'' Dow went on to say, ``Scripted questions may not adequately 
uncover issues or concerns and, from the perspective of the employee, 
may sound more like an interrogation than a fruitful dialogue.'' OSHA 
does not intend the discussion questions included in the preamble to be 
mandatory. They are presented to provide employers, and particularly 
smaller employers who are less likely than a company like Dow to be 
experienced in program evaluation, with ideas about the kinds of topics 
an evaluator might find useful when consulting with employees.
    Some rulemaking participants (Exs. 30-494, 30-3745, 30-3723, 32-
351-1, 30-4467) argued that employee participation in the evaluation 
process might be problematic. They evidently believe that requiring 
employers to consult with employees in problem jobs could subject the 
employer to citations. For example, the Forum for a Responsible 
Ergonomics Standard (Ex. 32-351-1) commented, ``If an employee deems 
the program ineffective, but the employer disagrees and implements no 
measures to improve effectiveness, the proposal appears to grant OSHA 
discretion to cite the employer for non-compliance.'' Morgan, Lewis & 
Bockius LLP (Ex. 30-4467) also raised concerns about employee 
participation in developing, implementing and evaluating the employer's 
ergonomics program: ``The latter is the most troublesome; employers 
could conceivably receive citations by virtue of a compliance officer's 
subjective determination that employees were not allowed to evaluate 
every aspect of the program. Moreover, if employees' suggestions for a 
program are rejected, the employer arguably could be said to have 
unlawfully limited employee participation in the ``development'' of a 
program. (Ex. 30-4467). ``
    Three other commenters, the Salt River Project (Ex. 30-710), the 
Integrated Waste Services Association (Ex. 30-3853), and Southern 
California Edison (Ex. 30-3284), argued that the proposed provision to 
consult with employees during evaluations was too open to subjective 
interpretation: ``The final standard should make clear that the 
employer is not required to act on a recommendation from employees if 
the employer can document that the recommendation is without merit'' 
(Ex. 30-3284).
    In response to these comments, OSHA notes that, in the Agency's 
experience, employee input is invaluable; employees are the best source 
of information on how a program is working in practice. However, 
employers are expected to use their judgment and to assess the value of 
any information they receive in the course of an evaluation, whether 
from a records review or employee consultations. Weighing input from 
many sources is standard management practice, and the rule anticipates 
that employers will continue to use their judgment in these matters. 
Further, OSHA intends employee participation in the ergonomics program 
to be active and meaningful, but this does not mean, as Morgan, Lewis & 
Bockius suggest, that they must be allowed to evaluate ``every aspect 
of the program'' (Ex. 30-4467).
    Paragraph (u)(1)(ii) of the final standard requires employers to 
``review the elements of the program to ensure they are functioning 
effectively.'' This requirement is nearly identical to the 
corresponding provision proposed. OSHA received a few comments on this 
proposed provision (see, e.g., Exs. 30-3031, 30-3813, 30-4334). Tesco 
Drilling Technology Inc. (Ex. 30-3031) stated: ``If OSHA does in fact 
believe that employers are best able to determine evaluation criteria, 
and that employers should be able to define ``functioning properly,'' 
why is OSHA proposing this cumbersome standard to begin with? If there 
is no specific evaluation criteria or goal in each element, how can a 
compliance officer issue a citation for noncompliance in any portion of 
the program?'' Organization Resources Counselors, Inc. (ORC) (Ex. 30-
3813) stated that the phrase ``functioning properly'' was vague, and 
comments received from Senator Bond, Chairman of the United States 
Senate Committee on Small Business (Ex. 30-4334), agreed with those of 
ORC: ``For an employer to evaluate its ergonomics program, it is to 
``evaluate the elements of [its] program to ensure they are functioning 
properly; and evaluate the program to ensure it is eliminating or 
materially reducing MSD hazards * * * The use of these terms, and 
others, throughout the proposed standard means that employers will be 
left to their own instinct and resources to decide whether they have 
met the obligations and gone far enough.''
    OSHA's reason for including this provision in the final rule is 
that evaluations of individual elements and their functioning often 
reveal program deficiencies that are undermining program effectiveness 
but could be difficult to detect if the employer only evaluated the 
program as a whole. For example, if employees are not reporting MSD 
hazards, it may mean that the management leadership and training 
components are not working properly. The final rule thus continues to 
require that employers evaluate each program element as well as the 
program as a whole. How this is done is left to employers, because the 
records, methods to be used, and cultures of workplaces differ markedly 
and no one approach is appropriate for all. The final rule does not 
include specific effectiveness measures for each element of the 
program, because these would vary extensively from one workplace to 
another. However, as commenters

[[<strong>Page</strong> 68417]]

recommended, the final rule does include examples of effectiveness 
measures that are useful in evaluating the effectiveness of programs as 
a whole.
    Paragraph (u)(1)(iii) of the final rule requires employers to 
``determine whether MSD hazards are being identified and addressed.'' 
The primary purpose of implementing an ergonomics program is the 
identification and control of MSD hazards. OSHA expects employers to 
establish evaluation criteria to assess the success of their program in 
meeting this goal. There are a wide variety of methods available to 
employers, ranging from a simple count of the number of problem jobs 
controlled to more sophisticated analyses, such as year-to-year trend 
analyses.
    Again, OSHA finds that employers are best able to determine the 
specific evaluation criteria that will most effectively tell the story 
of their efforts to identify and address MSD hazards. Commenting on the 
corresponding proposed paragraph, which would have required employers 
to evaluate their program to ensure it is ``eliminating or materially 
reducing'' MSD hazards, Milliken & Company (Ex. 30-3344) and others 
(Exs. 30-3749, 30-4674) argued that the proposed provision would 
require an evaluation to ensure that the program is eliminating MSD 
hazards, when a better measure might be the extent to which the program 
is reducing the incidence of MSDs. Nucor Corporation and Vulcraft-South 
Carolina (Exs. 30-3354, 30-3848, 30-4799, 30-4540, 601-x-1710) asked 
OSHA to add ``to the extent feasible'' to this provision on the grounds 
that doing so ``would keep the proposed regulation consistent in its 
requirements throughout all elements of an ergonomics program.''
    The Dow Chemical Co. (Ex. 30-3765) asked OSHA to modify this 
paragraph in the final rule by adding specific language at the end of 
the paragraph to read, ``or maintaining the risks at an acceptable 
level.'' In Dow's view, such a change would make it clear that 
instituting the same ``fix'' across the board may not eliminate all MSD 
injuries. Dow also was unclear about what the Agency meant by 
``materially reducing'' MSD hazards.
    The National Telecommunications Safety Panel (Ex. 30-3745) 
expressed similar concerns about the proposed phrase ``eliminating or 
materially reducing MSD hazards.'' The Panel argued that this language 
was misleading because, ``some MSDs exist epidemiologically in any 
workplace.'' SBC Communications Inc. (Ex. 30-3723) urged OSHA to delete 
the term ``eliminating or materially'' from the final rule because its 
use failed to recognize ``that some MSDs may exist epidemiologically in 
any workplace and that the program [envisioned by the standard] is 
realistic and performance-based.''
    Footwear Industries of America Inc. (Ex. 30-4040) commented that 
the inclusion of the proposed ``eliminating or materially reducing'' 
phrase suggested that ``employers will meet their obligations if they 
select and implement the controls that a reasonable person would 
anticipate would achieve a material reduction in the likelihood of 
injury. `` However, according to this commenter, ``the ``reasonable 
person'' standard is hardly a bright-line test and provides excessive 
enforcement discretion to OSHA inspectors when determining 
compliance.''
    OSHA has revised many provisions of the final rule in response to 
comments received and data submitted to the record. One of the more 
important changes is the revision to the language of paragraph (k), 
which tells employers what they must do to achieve compliance with the 
final rule's control requirements. The final rule no longer uses the 
phrase ``materially reduce,'' and paragraph (u)(1)(iii) therefore has 
been revised as well. The language of this provision now requires 
employers to ``determine whether MSD hazards are being identified and 
addressed.'' OSHA believes that this language is responsive to the 
concerns of those employers who interpreted the proposed language to 
mean that all MSD hazards had to be eliminated before an ergonomics 
program could be judged effective. The final rule, at paragraph (k), 
makes clear that OSHA will consider an employer to be in compliance 
with the standard's control requirements when it has implemented 
controls meeting any of the endpoints identified in that paragraph. 
There are clearly many ways to assess whether the program is 
identifying MSD hazards and dealing with them appropriately, as 
discussed above, and any method that is appropriate and accurate in 
making this assessment is acceptable to OSHA.
    A number of rulemaking participants ( Exs. 32-182, 32-111-4, 30-
167, 30-3826, 32-210-2, 32-85-3, 30-3686, 30-3826, Tr. 9088, Exs. 30-
3284, 30-240, Tr. 16578, Exs. 32-339-1, 500-218, 31-307, 30-3860, Tr. 
8982, Tr. 4372, Exs. 30-1726, 30-1726) commented that OSHA would 
clarify the proposed evaluation requirements significantly if it 
developed guidance materials and model evaluation tools for employers. 
For example, Organization Resources Counselors (ORC) (Ex. 30-3813) made 
comments that were representative of those of the above group when it 
asked OSHA to include a non-mandatory appendix of types of performance 
measures and approaches that OSHA would consider appropriate. In 
addition to the measures of effectiveness mentioned by OSHA in the 
proposed preamble, such as decreases in the numbers or rates of MSDs 
and decreases in severity, ORC suggested a few others: ``Measures might 
include reduced workers' compensation claims for MSDs, use by the 
employer of periodic symptoms surveys and other indicia of effective, 
early reporting, or demonstration that risk factors have been reduced 
and/or tools and equipment have been modified.''
    Two other commenters, the American Federation of State, County and 
Municipal Employees (AFSCME) (Ex. 32-182) and the United Steelworkers 
of America (Ex. 32-11-4), argued that such tools were necessary. They 
criticized the proposed evaluation provisions in general, because they 
failed to provide any criteria to aid employers in determining if their 
ergonomics programs were effectively eliminating or materially reducing 
MSDs. The American Association of Occupational Health Nurses (AAOHN) 
(Exs. 30-3686, 30-2387) also urged OSHA to assist employers by 
providing standardized evaluation forms.
    OSHA agrees that providing employers with evaluation tools and 
forms would be helpful to employers, employees, and OSHA Compliance 
Officers. In the period between publication of the final rule and the 
compliance dates for program evaluation, the Agency plans, if resources 
permit, to develop and disseminate such materials.
    AM Moving and Storage Association (Ex. 500-82) argued that the 
standard as a whole would be infeasible for its member companies: ``if 
it is not feasible for movers to implement controls that would 
eliminate and materially reduce MSD hazards, then it is equally 
impossible for moving and storage companies to monitor and track the 
progress of the proposed ergonomics program.'' OSHA is not, in this 
standard, requiring employers to implement infeasible controls or to 
reach infeasible hazard control endpoints. Instead, OSHA is requiring 
employers to take reasonable measures to protect their employees from 
MSD hazards. OSHA expects that moving companies also will find 
effective ways of reducing the number and severity of their MSD 
hazards.

[[<strong>Page</strong> 68418]]

    The Union of Needletrades, Industrial and Textile Employees (UNITE) 
(Ex. 32-198-4) argued that the proposed evaluation section would be 
ineffective. They commented that the proposed evaluation requirements 
overall were too narrow and ``must be expanded to determine actual 
effectiveness of the existing program.'' OSHA agrees, and has expanded 
the final rule's evaluation requirements to include a requirement that 
employers assess their programs using indicators of effectiveness, such 
as reductions in the number, rate, or severity of MSDs. OSHA believes 
that the final rule's combination of qualitative and quantitative 
approaches to program evaluation will ensure the effectiveness of the 
programs implemented to comply with this rule.

Paragraph (u)(2)--Program Evaluations at More Frequent Intervals 
Triggered by Events

    Paragraph (u)(2) of the final rule requires an employer to evaluate 
the program, or a relevant part of it, when the employer has reason to 
believe that the program, or an element of the program, is not 
functioning as intended; when operations in the workplace have changed 
in a way that is likely to increase employee exposure to ergonomics 
risk factors and MSD hazards on the job; and, at a minimum, once every 
three years. Thus, the final rule retains the minimum 3-year evaluation 
frequency proposed but provides greater specificity than did the 
proposal about the events that trigger evaluation at more frequent 
intervals.
    The proposed language on the frequency of program evaluation, which 
required employers to evaluate their programs ``periodically, and at 
least every 3 years,'' was performance-based rather than specific 
because of the diversity of workplaces covered by the rule. OSHA 
defined periodically in the proposal as a process or activity that is 
``performed on a regular basis that is appropriate for the conditions 
in the workplace'' and ``is conducted as often as needed, such as when 
significant changes are made in the workplace that may result in 
increased exposure to MSD hazards.'' Thus, the proposed provision on 
the frequency of required evaluations was designed to reduce 
unnecessary burdens on employers whose workplaces, for example, changed 
little over time, while ensuring that program evaluations, which are 
essential to program effectiveness, were conducted at some minimal 
frequency. The final rule reflects the same principles but has been 
revised to provide the additional specificity requested by commenters.
    OSHA continues to believe, as explained in the proposal, that the 
employer is in the best position to determine how often the ergonomics 
program at a particular work site needs to be evaluated to ensure its 
effectiveness. A site undergoing process or production changes, for 
example, or one experiencing high turnover, may need more frequent 
evaluations than other, less dynamic, workplaces. Workplaces with these 
characteristics are addressed by final rule paragraph (u)(2), which 
requires employers faced with changes in operations that are likely to 
increase employee exposure to evaluate their programs when such changes 
occur. Similarly, an increase in the number or severity of MSDs in the 
workplace would suggest that a program evaluation is warranted. This 
situation is one that would be covered by paragraph (u)(2) of the final 
rule; such an increase clearly suggests that the program, or a part of 
it, has failed to operate properly. In work environments with a stable 
workforce and work operation, program evaluations conducted once every 
three years may be sufficient. For these workplaces, the minimum 
frequency required by paragraph (u)(1) may apply.
    As noted in the proposal, current industry practice as to the 
appropriate frequency of ergonomics program evaluations in specific 
environments is available from other sources. For example, the 
Meatpacking Guidelines (Ex. 2-13) recommend semi-annual reviews by top 
management to evaluate the success of the program in meeting its goals 
and objectives. In addition, a wide range of companies with successful 
ergonomics programs evaluate these programs at regular intervals.

Paragraph (u)(3)--Correcting Program Deficiencies

    Paragraph (u)(3) of the final rule requires employers to correct 
any deficiencies identified by the evaluation. It also requires that 
employers correct such deficiencies promptly. Deficiencies are findings 
that indicate that the ergonomics program is not functioning 
effectively because, for example, it is not successfully controlling 
MSD hazards or is not providing needed MSD management. OSHA requires 
employers to respond to deficiencies in the ergonomics program by 
taking actions such as: identifying corrective actions to be taken; 
assigning the responsibility for these corrective actions to an 
individual who will be held accountable for the results; setting a 
target date for completion of the corrective actions; and following up 
to make sure that the necessary actions were taken. In a very small 
workplace, of course, such detailed planning would likely not be 
necessary.
    Some commenters, including Milliken & Company (Ex. 30-3344) and 
(Exs. 30-3749; 30-4674), stated that the proposed requirement to 
correct program deficiencies discovered during an evaluation would 
create a ``needless second tier of violations on top of the underlying 
substantive requirement that is not being met.'' Moreover, they argued 
that, ``the requirement to promptly take action to correct deficiencies 
does not provide sufficient latitude for employers to implement 
corrections within a time frame that will be reasonable in every 
case.'' Tesco Drilling Technologies (Ex. 30-3031) also expressed 
concern about an employer's liability once program deficiencies have 
been identified. Tesco asked, ``What are the criteria by which a 
compliance officer can issue a citation under this provision. * * * If 
a citation can not be issued, how can this be enforced? If it cannot be 
enforced, how can it be a rule?''.
    In response, OSHA wishes to emphasize that its primary goal is to 
protect employees from MSD hazards, not to hold employers liable for 
ergonomics program deficiencies. OSHA expects that even the best 
programs will find deficiencies in their ergonomics program at one time 
or another. OSHA's concern is whether or not the employer has acted on 
the information obtained during the program evaluation and is taking 
steps to correct the problems identified. Employers who act in good 
faith to correct identified program deficiencies clearly will satisfy 
this requirement. However, employers who identify ergonomic program 
deficiencies through the evaluation process and then do not act on this 
information may not be in compliance with this requirement.
    The final rule does not specify the time frame within which 
identified program deficiencies must be corrected. The Agency 
recognizes that the time needed to correct a program deficiency will 
vary according to many factors. For example, the following factors may 
influence an employer's response time:

--The nature of the MSD hazard;
--Previous attempts to correct the problem;
--The complexity of the needed controls;
--The expense of the needed controls;
--Whether the hazard is a higher or lower priority in the list of 
identified program deficiencies; and
--The expertise needed to control the hazard.


[[<strong>Page</strong> 68419]]


    Some rulemaking participants (Exs. 30-3853, 30-3765, 30-710, 30-
240) commented that OSHA was not clear about what kind of program 
deficiencies needed correction or what ``as quickly as possible'' 
meant. Edison Electric Institute's (EEI) comment (Ex. 30-3853) was 
representative of the views of those commenters concerned about the 
time frame for correcting deficiencies: EEI stated that the proposed 
requirement to correct ergonomics program deficiencies ``as quickly as 
possible'' was vague and unenforceable. August Mack Environmental Inc. 
(Ex. 30-240) stated that, in many cases, the responsibility for 
correcting deficiencies found will be transferred to a program 
administrator, who may be so overwhelmed with other duties, including 
those of the ergonomics program, that he or she may not be able to 
respond in a reasonable period of time. ``My concern is that a 
deficiency may be found and assigned to the program administrator who 
will work the problem into his or her overall priority system, so that 
it can be fixed,'' August Mack posited. ``However, if inspected in the 
meantime, OSHA will find that this is not responsive enough.''
    Again, OSHA's aim in including program evaluation requirements in 
the final rule and in requiring deficiencies identified through 
evaluation to be corrected promptly is not to catch employers in 
violations but to ensure that the employer's ergonomics program is 
working correctly. If employers have identified deficiencies, corrected 
those that can be addressed quickly and easily, prioritized those 
requiring longer to correct, and are making reasonable progress in 
addressing prioritized deficiencies, they likely will be in compliance 
with these requirements.
    The Dow Chemical Company (Ex. 30-3765) argued that the proposal was 
unclear as to what program deficiencies were being addressed. ``Dow 
simply does not understand whether the evaluation in this section is 
the same evaluation of the program required in other sections as an 
employer deals with identified problems or whether it is an evaluation 
of the program addressing every element of this regulation. If it is 
the first case, then the section is redundant and should be removed. If 
it is the latter case or both, then the Preamble and section should be 
rewritten to clearly explain this.'' OSHA is unclear about the meaning 
of Dow's comment, but believes that the final rule's clear requirements 
for program evaluation will shed light on the issues of concern to 
them.
    Dow (Ex. 30-3765) also voiced concern that the proposed evaluation 
section seemed, in their opinion, to unfairly shift the burden of 
correcting program deficiencies to the employer without considering the 
employee's contribution to such deficiencies. Dow argued that the 
burden of correcting deficiencies should not be placed completely on 
the shoulders of the employer. ``Because ergonomics is focused on how 
an individual interacts with his or her workplace, Dow believes that 
the employee must have some responsibility for making appropriate 
changes in their activities.'' Dow suggested that OSHA include an 
``Employee Responsibility'' section in the final standard that would 
state that if employees are not following what they are supposed to do 
under the rule, their employers will not be cited for violating this 
standard.
    OSHA disagrees with Dow's views in the matter of employee 
responsibilities. It is the employer, not the employee, who controls 
the conditions of work. If an employee, as Dow's comment suggests, is 
not observing appropriate work practices, it is the employer's 
responsibility to compel compliance. Employers must manage the 
conditions in their workplace; they must lead by example, train their 
employees in the use of controls and safe work practices, reinforce 
such practices, and, if necessary, establish a disciplinary system so 
that employees understand that they must follow safe and healthful 
practices on the job. However, OSHA does not believe that employers 
must be the ``insurers'' of their employees' behavior. If, for example, 
an employer establishes, implements, trains employees in, and enforces 
safe work practices, and does so in a consistent manner, the employer 
will not be liable for an employee's unforeseeable violation of its 
safety rules.
    In contrast to those commenters who found the proposed provisions 
vague, some commenters found the proposed evaluation requirements too 
specific. For example, the Eastman Kodak Company (Ex. 30-429) argued 
that only the proposed basic obligation should be included in the final 
rule and that the specific requirements should be deleted: ``We believe 
. . . [these requirements address] general management practices that 
should not be mandated but should be provided in a non-mandatory 
appendix.''
    OSHA believes that the final rule's provisions provide employers 
with the steps to follow to conduct an effective and efficient program 
evaluation. Absent such provisions, many employers, particularly 
smaller ones, would not know how to conduct an evaluation. Accordingly, 
the final rule includes paragraphs (u)(1) and (2), which mandate 
certain evaluation steps and procedures and establish the minimal 
frequencies of periodic program evaluations. Many employers, however, 
such as Kodak, who have had ergonomics programs for years, are unlikely 
to need such direction.
    The Labor Policy Association, Inc. (LPA) (Ex. 30-494), the 
Department of Defense (Tr. 9085-9086) and ( Ex. 30-3781) cautioned OSHA 
about the difficulties that could arise from doing a program evaluation 
shortly after creating a new ergonomics program. Specifically, the LPA 
argued that ``newly implemented ergonomics programs typically 
experience a spike in reported MSDs that at some point levels off and 
begins to drop. However, it can take as long as four years before the 
drop starts to occur. Under the standard, an employer whose reported 
MSDs were increasing would be required to implement different 
mechanisms to correct the program's deficiencies. However, an OSHA 
compliance officer could view this as evidence of an ineffective 
ergonomics program and launch an in-depth compliance review, even 
though the increase in MSDs is a natural outcome of having a new but 
effective program.'' Similarly, the DOD argued that time must be 
allowed to elapse for ergonomics programs to gather data needed for 
evaluations.
    OSHA is fully aware that the number of MSDs reported may increase, 
and often substantially, in the first year or so after program 
implementation. The Agency believes that the examples of effectiveness 
measures OSHA includes in final paragraph (u)(1)(iv) are sufficiently 
varied to be suitable for workplaces with programs at various stages of 
maturity.
    Finally, the UFCW (Ex. 32-210-2) asked OSHA to require employers to 
respond to and, if warranted, address issues raised by employees during 
a program evaluation. ``The employer should be required to take action 
to reduce or eliminate hazards uncovered by an evaluation based upon 
employee concerns. This type of response and evaluation will only serve 
to strengthen the entire ergonomics program by building confidence 
among employees that they are a valuable source of information and also 
can be part of the evaluation process.'' OSHA believes that employers 
will respond to employee concerns during evaluations when they seek 
inputs from them about the effectiveness of the program. To do 
otherwise would be inefficient as well as non-responsive. This does not 
mean, of course, that employers must respond to all employee 
suggestions, as some commenters feared (see, e.g., Exs. 30-

[[<strong>Page</strong> 68420]]

3284, 30-3853, 30-710). Because OSHA believes that such two-way 
communication will be encouraged by the final rule's evaluation 
provisions, the Agency has decided not to mandate such responses in the 
final rule's program evaluation provisions.

Paragraph (v)--What Is My Recordkeeping Obligation?

    The final recordkeeping provisions specify that employers (except 
those with fewer than 11 employees) must keep those records essential 
to any effective ergonomics program. OSHA observed in the proposal (64 
FR 65861) and continues to be convinced that occupational injury and 
illness records are a vital part of an effective ergonomics program in 
all but the very smallest establishments. Records provide employers, 
employees, and consultants with valuable information on conditions in 
the workplace and can be used to identify trends over time and to 
pinpoint problems. However, OSHA also continues to recognize the need 
to reduce paperwork burdens for all employers, especially small 
employers, to the extent that this can be done without reducing safety 
and health protections. OSHA proposed to limit both the kinds of 
records employers were required to keep and the applicability of the 
standard's recordkeeping requirements to very small employers. With 
very few changes, the final rule contains the recordkeeping 
requirements that were proposed. OSHA believes that the approach to 
recordkeeping in the final rule is consistent with the Paperwork 
Reduction Act's emphasis on minimizing paperwork burdens for small 
employers whenever possible.
    Because larger employers have more complex workplace organizations, 
OSHA proposed that larger employers would be required to keep records 
of employee reports of MSDs and the employer's responses to them; the 
results of job hazard analyses; records of Quick Fix controls; records 
of controls implemented in problem jobs; program evaluations; and 
records of the MSD management process. OSHA proposed to exempt 
employers with fewer than 10 employees from the standard's 
recordkeeping requirements because in these very small workplaces, 
information can be communicated and retained informally. The final rule 
requires that employers with ergonomics programs keep the same records 
as those proposed. However, the final rule expands the recordkeeping 
size threshold from 10 employees to 11 employees. This expansion will 
make the recordkeeping size threshold for this rule consistent with 
that for OSHA's recordkeeping rule (29 CFR Part 1904).
    The following paragraphs discuss the specific requirements of the 
recordkeeping provisions of the final ergonomics rule and the comments 
OSHA received in response to the proposed recordkeeping requirements. 
OSHA has carefully evaluated participants' comments concerning the 
records needed for effective ergonomics programs to assure that the 
final standard only requires employers to keep those records that are 
necessary, i.e., those records that have utility to employers, 
employees, and OSHA.
    Paragraph (v) of the final rule, entitled ``What is my 
recordkeeping obligation?'' establishes which employers must meet the 
rule's requirements for recordkeeping. This provision requires 
employers with more than 10 employees at any time during the previous 
calendar year to keep records of their ergonomics program. Employees to 
be counted toward this total include part-time and seasonal employees 
and employees provided through personnel services. Under the proposed 
rule, employers with fewer than 10 employees would have been exempt 
from having to keep any ergonomics program-related records. As noted 
above, the final rule increases this size threshold to ``more than 10 
employees.'' OSHA's experience indicates that, because of the absence 
of management layers and multi-shift work, informal communication may 
be used in very small companies, and formal recordkeeping systems may 
not be necessary. A very small establishment may have a very simple and 
informal, but nevertheless effective, ergonomics program that does not 
need written records.
    OSHA proposed, and the final rule includes part-time and seasonal 
employees and employees provided through personnel services when they 
count the number of employees they employed at any time during the 
previous year. As explained in the proposed preamble (64 FR 65861), 
these part-time and temporary employees are retained and supervised by 
the employer on a daily basis even though this may be the case only for 
a limited time. As discussed above, establishments with more than 10 
employees generally should be required to keep records because they are 
likely to have more than one layer of management and therefore need to 
have written procedures. In addition, if these employees were not 
counted toward the size threshold for recordkeeping, large workplaces 
that operate with few permanent employees but numerous temporary 
employees (an organizational structure that is increasingly common) 
would not be required to keep records despite several levels of 
management and more formal methods of communication.
    The proposed rule's exemption for very small employers elicited 
several comments. These comments addressed the usefulness of the 
standard's small business recordkeeping exemption and argued that part 
time, seasonal, or leased employees should not be included in the count 
of employees that triggers recordkeeping. In addition, the Department 
of Navy commented on the future applicability of the standard to 
federal facilities.
    Usefulness of the small business recordkeeping exemption. Some 
rulemaking participants (see, e.g., Exs. 30-2493, 3596; Tr. 2982-83, 
Tr. 8394, Tr. 15522, Tr. 15565) argued that the proposed small business 
exemption would not be useful to small businesses because small 
employers would choose to keep records anyway. For example, the 
National Federation of Independent Business (Ex. 30-3596, pp. 4-5) 
stated that

    OSHA has touted its paperwork exemption and ``quick fix'' 
alternatives to the full ergonomics program requirements as 
provisions in the ergonomics standard that were revised to appease 
small business concerns. Although a ``paperwork exemption'' may 
appear to help on its face, a small-business owner would be ill-
advised not to write down and keep records of everything related to 
their ergonomics program when faced with the constant possibility of 
an OSHA inspection.

This comment echoes statements made by the small entity representatives 
who participated in the Small Business Regulatory Enforcement Fairness 
Act (SBREFA) panel for this rule. These representatives maintained that 
they would choose to keep records even if they were not required by the 
standard to do so (Ex. 23). In response to these small business 
commenters, OSHA notes that employers are always free to keep any 
records that they wish to maintain, but the final rule does not require 
them to do so.
    Part-time workers should not count toward the total. Some 
rulemaking participants (see, e.g., Tr. 3324, Tr. 5638-39) indicated 
that the provision describing which employers must keep records needed 
to be clarified and simplified to state explicitly that seasonal, 
leased, and part-time employees should be included in the total count. 
Other commenters (see, e.g., Exs. 30-240, 429, 1090) felt that the 
inclusion of temporary, seasonal, and part-time employees in the count 
of employees was burdensome or

[[<strong>Page</strong> 68421]]

unnecessary. For example, The Eastman Kodak Company (Ex. 30-429, p. 8) 
remarked that


    This creates significant difficulties in that the prior health 
histories of such workers are unknown to the contracting employers 
and initial health checks are usually not conducted. Personnel 
service workers could have pre-existing conditions that could become 
aggravated without MSD factors being present in their workplaces.

    OSHA's rationale for including these employees is that it is the 
number of employees, not the duration or kind of employment 
relationship they have with the employer, that necessitates the keeping 
of records. The size of the workforce is the factor that makes layers 
of management and more formal methods of communication (and therefore 
recordkeeping) necessary. In fact, supervising part-time or leased 
employees often adds considerable complexity to management planning, 
oversight, and recordkeeping. Thus, the final rule uses a workforce of 
more than10 employees on any day of the previous calendar year as the 
size threshold that triggers compliance with the rule's recordkeeping 
requirements.
    Applicability to federal facilities. In a comment unique to federal 
agencies, the U. S. Department of Navy (Ex. 30-3818, p. 2) recommended 
that OSHA ``acknowledge the different recordkeeping requirements for 
federal agencies and rewrite * * * [the standard] to include provisions 
for the federal facilities recordkeeping program of 29 CFR 1960.'' OSHA 
has considered this request, but has decided that a separate provision 
stating the applicability of the rule to federal facility recordkeeping 
programs is unnecessary because this matter is better addressed in a 
compliance directive for affected federal agencies.
    Paragraph (v) of the final rule, which corresponds to section 
1910.940 of the proposed rule, establishes the final rule's 
requirements for keeping the records required by the standard. It 
specifies which records employers must keep and how long they must keep 
them. OSHA proposed that employers required by the standard to keep 
records maintain the following:
    <bullet> Employee reports of MSDs and the employer's responses to 
these reports,

II The results of job hazard analyses and Quick Fixes,
II The controls implemented to reduce or eliminate MSD hazards,
II The MSD management process, and
II The results of ergonomics program evaluations.

    OSHA also proposed that most ergonomic program records be retained 
by the employer for 3 years or until replaced by an updated record, and 
the final rule mandates the same retention periods. The final rule, 
like the proposal, makes an exception to the 3-year retention period 
for MSD management records. These records are required to be maintained 
for the length of the injured employee's employment plus 3 years, a 
retention period considerably shorter than that required for other 
OSHA-mandated medical records. OSHA health standards, for example, 
generally require exposure records to be kept for 30 years and medical 
surveillance records to be kept for the duration of employment plus 30 
years, as required by 29 CFR 1910.1020, OSHA's access to employee 
exposure and medical records standard. These lengthy retention periods 
are appropriate for many toxic substances and harmful physical agent 
standards because of the long latency between exposure on the job and 
the onset of disease. However, since the latency period for most 
musculoskeletal disorders is shorter than is the case for many of the 
chronic conditions and illnesses covered by other OSHA rules, the 
Agency believes that a shorter retention period is appropriate for the 
ergonomics rule. Also, changes in the workplace, such as equipment or 
process changes, often make older ergonomics records irrelevant to 
current jobs and the present workplace environment. Employers' 
ergonomics programs continue to evolve, with records of the most recent 
aspects of that evolution being the most relevant for employee 
protection.
    The proposed recordkeeping provisions elicited several comments. 
Commenters addressed the following issues: the potential burden imposed 
by the recordkeeping requirements; the kinds of records employers 
should keep; the appropriate retention period for program-related 
records; the need to permit employees and designated representatives to 
access the records; and electronic recordkeeping. The paragraphs below 
discuss the comments; OSHA's responses to the comments follow this 
discussion.
    Several rulemaking participants agreed with OSHA's proposed 
recordkeeping requirements (see, e.g., Exs. 32-339-1, 182-1; Ex. 500-
206; Tr. 3488). Typical of the views of these commenters was the 
comment of the AFL-CIO (Tr. 3488) ``The recordkeeping provisions of the 
rule * * * are necessary for the effective implementation of the 
program.''
    Recordkeeping requirements are burdensome. A number of rulemaking 
participants (see, e.g., Exs. 30-74, 294, 429, 526, 544, 546, 652, 653, 
710, 1070, 1090, 2428, 2433, 2807, 2991, 3284, 3336, 3367, 3557, 3593, 
3723, 3745, 3765, 3770, 3781, 4134, 4184, 4185, 4628, 4839; Exs. 32-77-
2, 300-1; Exs. 500-7, 16, 113, 130, 145, 163; Tr. 3136-37, Tr. 5039, 
Tr. 5334-35, Tr. 5493, Tr. 5638, Tr. 9207-9209, Tr. 12198-99, Tr. 
12770, Tr. 12860, Tr. 16486-87, Tr. 16491, Ex. 500-163) argued that the 
proposed recordkeeping requirements were excessive, burdensome and 
unnecessary. For example, a commenter for Owens Corning (Ex. 500-163, 
p. 7) stated that

    The recordkeeping requirements in the proposed standard are 
excessive and poorly defined. In addition, the implied documentation 
requirements of the proposed standard are inconsistent with the 
requirements of * * * [the proposed rulemaking section], i.e., the 
real recordkeeping requirements are much more extensive than those 
specifically required by this section.

    OSHA also received numerous pre-and post-hearing form letters to 
the effect that the proposed recordkeeping section was burdensome or 
unnecessary (see, e.g., Exs. 30-2252, 2251, 2360, 4226, 4748, 0382, 
2973, 2224, 0591, 0422, 1126, 4684, 4794, 2246, 0382, 2747, 3331, 2244, 
2337, 2888, 3517, 0176, 2902, 639, 2874, 4624, 3090, 0070, 2794, 5104, 
4402, 1073, 2999, 2033, 2097, 2345, 1304, 2908, 4404, 5187, 4718, 2354, 
2359, 4269, 4690, 691, 3201, 3400, 2866, 0597, 1806, 0912, 4605, 2343, 
2130, 4422, 1931, 2258, 2998, 2827, 0378, 2342, 2939, 2298, 4946, 2787, 
3403, 3293, 2938, 2450, 1672, 2995, 4440, 4944, 2317, 4446, 2853, 0569, 
2877, 2994, 2953, 2096, 3130, 1603, 2763, 2885, 3451, 1026, 2884, 2924, 
4795, 0455, 2336, 0433, 2197, 1540, 2758, 4796, 2972, 2858, 3294, 4416, 
2971, 4798, 4432, 1085, 4657, 2755, 5098, 3982, 5080, 5057, 5053, 2977, 
2979, 5009, 3852, 5070, 2978, 3970, 4768, 3983, 4806, 2469, 3971, 3935, 
5075, 5078, 2974, 2980, 4802, 2976, 3005, 2975, 2981, 5026, 3798, 2982, 
2526, 2285, 3995, 4785; Exs. L30-4958, 4964, 4967, 5211; Exs. 601-X-
249, 419, 1298; Exs. 500-1-224, 225, 226, 228, 229, 230, 231, 232, 233, 
234, 235, 236, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 249, 
250, 251, 252, 253, 254, 255, 256, 257, 259, 260, 261, 262, 263, 264, 
265, 266, 267, 268, 269, 270, 271, 272, 273, 273, 274, 275, 276, 277, 
278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 
292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 
306, 307, 309, 310, 311, 312, 313, 314, 315, 316, 318, 319, 320, 321, 
322, 323, 324, 325, 326, 327, 328, 329, 331, 332, 333, 334, 335, 336, 
337, 338, 339, 340, 341, 342, 343,

[[<strong>Page</strong> 68422]]

344, 345, 346, 347, 348, 349, 350, 351, 352, 353, 354, 355, 365, 366, 
367, 368, 369, 370, 371, 387, 388, 389, 390, 391, 392, 393, 394, 395, 
396, 398, 399, 400, 401, 402, 403, 405, 406, 407, 408, 409, 410, 411, 
412, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424, 425, 426, 
427, 428, 429, 430, 431, 432, 433, 434, 435, 436, 437, 438, 439, 440, 
441, 453, 456, 459).
    Some proposed records are not required. Some rulemaking 
participants questioned the need to keep certain of the records OSHA 
proposed that employers retain (see, e.g., Exs. 32-3004, 30-294, 30-
494, 30-2433, 30-1294, 30-3356, 30-4628, 500-177-2). These commenters 
argued that the OSHA Log, medical records, and program evaluations were 
all that were needed (Ex. 32-300-1), that Quick Fix records were 
unnecessary (Exs. 30-294, 30-494, 30-2433), that records of 
``preventive'' or ``voluntary'' work restrictions should not have to be 
kept (Exs. 30-1294, 30-3356, 30-4628, Ex. 500-177-2), and that employee 
reports of MSDs or their signs and symptoms were not needed (Ex. 30-
2433).
    The reasons given by these commenters varied. For example, the 
Edison Electric Institute (Ex. 32-300-1) believes that only a few 
records are needed for effective programs: ``The current required 
recordkeeping records including the OSHA 200 Log and medical records 
along with the program evaluation should be sufficient to maintain a 
current and effective ergonomics program.'' The Exxon-Mobil Corporation 
saw no value in keeping records of employee reports of MSDs (Ex. 30-
2433, p. 4), stating that

    The [proposed] standard calls for detailed records of job hazard 
analyses and hazard control tracking which establishments do not 
normally maintain. For example, if a computer monitor is raised 2 
inches by use of a monitor block, that action--and any subsequent 
adjustment to the height--must be documented and the document 
retained. Furthermore, most of the records OSHA proposes to be 
maintained are not necessary for an ergonomics program. OSHA should 
revisit the recordkeeping requirements and remove the requirements 
for employee reports and responses, and quick fix controls.

    The Dow Chemical Company (Ex. 30-3765) saw no value in keeping 
records of job hazard analyses for 3 years: ``Job hazard analyses 
should only be kept while the employer is working through solutions to 
reduce the risk of the hazard to an acceptable level.''
    The appropriate retention period. The proposed 3-year retention 
period also elicited several comments; commenters suggested periods 
ranging from 90 days to more than 30 years. Several rulemaking 
participants (see, e.g., Exs. 30-297, 3913, 4538; Exs. 32-85-3, 339-1, 
(185-3-1); Tr. 3488) stated that the standard's record retention 
periods should be set at five years in the final rule, to be consistent 
with the retention period for the Log of Injuries and Illnesses and 
related records found at 29 CFR 1904.6. The Dow Company commented that 
the proposed retention periods were too long, arguing that ``[t]here is 
no safety or health reason for keeping records beyond their 
usefulness'' and recommending that job hazard analyses ``should only be 
kept while the employer is working through solutions to reduce the risk 
of the hazard to an acceptable level.'' (Ex. 30-3765, p. 116) August 
Mack Environmental Inc. agreed that the proposed 3-year retention 
period was appropriate, without providing additional reasons why (Ex. 
30-240, p. 367).
    Some rulemaking participants (see, e.g., Ex. 30-3686; 31-353) 
stated that medical records related to employee exposure to ergonomic 
risk factors should be kept for the duration of employment plus 30 
years, as OSHA requires for other records covered by 29 CFR 1910.1020, 
OSHA's access to employee exposure and medical records standard, while 
another commenter (Ex. 30-525) stated that all of the records required 
by the standard should be kept according to the requirements of 29 CFR 
1910.1020. Another commenter, the National Telecommunications Safety 
Panel (Ex. 30-3745, p. 16), expressed concern that the proposed 
recordkeeping requirements could potentially conflict with those of 29 
CFR 1910.1020 and might raise employee privacy issues because some of 
the records could be ``[p]ersonal and individual in nature (e.g. job 
hazard analyses to accommodate individual injury or illness)'' and 
``[p]rivacy issues beyond mere compliance with [proposed] 1910.940.''
    Many commenters (see, e.g., Exs. 30-2116, 2809, 2825, 2847; 3001, 
3033, 3034, 3035, 3258, 3259, 3332, 4159, 4534, 4536, 4546, 4547, 4548, 
4549, 4562, 4627, 4776, 4800, 4801) maintained that all records other 
than MSD management records should be kept for 10 years. Representative 
of these comments, Gladys Vereesi argued that a 10 year retention 
period would allow an ergonomics program to improve upon past history, 
that a 3-year retention period limited the inputs for ergonomics 
program evaluation and that ``[i]mportant lessons learned will be lost 
(Ex. 30-2116, p. 9).
    Access to the records kept. Many rulemaking participants (see, 
e.g., Exs. 30-2809, 3001, 2116, 2825, 2847, 3033, 3034, 3035, 3258, 
3332, 4159, 4536, 4546, 4547, 4548, 4562, 4627, 4776, 4800; Exs. 32-
339-1, 185-3; Ex. 500-218; Tr. 3488) stated that the final rule should 
explicitly provide for access by employees or their designated 
representatives to all records required by the standard. Typical of the 
views of these commenters is the comment of the United Automobile 
Workers (Ex. 32-185-3-1, p. 7), which stated:

    Other matters discussed in this section * * * are employee 
reports and responses, and control records. First, it should be 
clear that these are available to affected employees and their 
representatives.

    Electronic records. The American Trucking Associations, Inc. (Ex. 
30-3330) asked OSHA to add the phrase ``in paper, photographic, 
microfilm, microfiche, CD-ROM, electronic or other appropriate format'' 
to allow employers to ``[t]ake advantage of less costly records storage 
alternatives while ensuring retention of the required records * * *''
    Responses to comments received. In this section, OSHA specifically 
responds to the issues raised by commenters on the proposed 
recordkeeping provisions.
    First, some commenters (see, e.g., Exs. 30-297, 30-3913, 32-85-3, 
32-339-1, Tr. 3488) argued that the ergonomics standard should not have 
separate recordkeeping provisions but instead that the Agency's 
recording and reporting rule (the ``recordkeeping rule'') (29 CFR Part 
1904) should govern such requirements. These commenters are confused 
about the purpose of that rule, which is to record all occupational 
injuries and illnesses that meet the rule's recordability criteria. 
Part 1904 does not address the records necessary for an effective 
safety and health program or the records that must be kept by employers 
to comply with the Agency's substance-specific or hazard-specific 
rules, such as this ergonomics program rule. It is routine and 
appropriate for rules addressing specific hazards, such as the confined 
spaces rule (29 CFR 1910.146), the lockout/tagout rule (29 CFR 
1910.147), and many others, to include recordkeeping requirements 
geared to those hazards. Accordingly, OSHA has not adopted this 
suggestion.
    Many commenters (see, e.g., Ex. 30-2428, Tr. 9207, Ex. 32-21-1-2) 
argued that the rule's recordkeeping requirements are unnecessarily 
burdensome. OSHA disagrees. Employers must keep records of their 
program activities for a variety of reasons: to ensure that the program 
is

[[<strong>Page</strong> 68423]]

working as intended and that resources are not being wasted; to ensure 
that MSDs are being addressed effectively, that employees are reporting 
their signs and symptoms as early as possible, and that Quick Fix and 
other controls are working; and to ensure that MSD management is 
helping injured employees to recover as soon as possible. OSHA believes 
that the records required by the final rule are the minimum necessary 
for an effective program. Simply relying on 200 Logs, medical records, 
and evaluation records, as the Edison Electric Institute suggested (Ex. 
32-300-1) would mean that an employer would not have records of the 
controls implemented, the kinds of MSD signs and symptoms occurring, or 
the methods used to conduct job hazard analysis at the establishment. 
In this respect, OSHA agrees with the views of one commenter (Tr. 7420) 
who noted that there is often a discrepancy between the data on an 
establishment's 200 Log and what is happening on the floor: ``When you 
actually review the first report of injury, you will conclude that the 
OSHA 200 Log * * * has no report of cumulative trauma and/or repetitive 
strain injury when in fact musculoskeletal disorders are at epidemic 
proportions.'' OSHA believes that most employers would agree that all 
of the records required by the final rule will provide information 
essential to effective ergonomics programs.
    As to the suggestion (see, e.g., Exs. 30-297, 30-3913, 32-185-3-1) 
that the retention period be 5 years instead of 3 years to coincide 
with OSHA's retention periods under the recordkeeping rule, OSHA notes 
that the 3-year retention period specified in the final rule is 
consistent with the frequency of required program evaluations, where 
these records will be most useful. However, employers are always free 
to keep their records for longer retention periods if doing so is 
consistent with or beneficial to their management practices. Also, even 
where an employer is permitted under paragraph (y) of the final rule to 
discontinue the ergonomics program for a job, the employer must still 
keep the records required to be kept under paragraph (v) for the amount 
of time listed in paragraph (v)(4).
    OSHA agrees that employers may keep these records electronically, 
and paragraph (v)(1) of the final rule makes this clear.
    Some commenters (see, e.g., Exs. 30-1294, 30-3356) urged OSHA not 
to require that records of temporary work removals or work restrictions 
be kept if such removals or restrictions were ``preventive'' or 
``voluntary'' in nature. OSHA is unclear about what the commenters 
meant by ``voluntary'' or ``preventive'' restrictions. If the 
restriction is assigned after the employee reports signs or symptoms, 
the employee has experienced an MSD incident, and removal or 
restriction must be treated in accordance with the requirements in 
paragraph (v)(1). The restriction or removal of a symptomatic employee 
is thus simply a temporary work removal or restriction, as those terms 
are used in the final rule. If, on the other hand, the employer assigns 
an employee to another job before that employee is symptomatic, the 
reassignment is simply an administrative control, i.e., job rotation. 
Records of work restrictions or removals are required to be kept by the 
final rule; records of routine job reassignments or rotations (i.e., 
those not done as part of the employer's strategy to control or 
eliminate MSD hazards) are not.
    OSHA agrees with those commenters (see, e.g., Exs. 30-2809, 32-339-
1, 32-185-3, 500-218) who pointed out that the proposal failed to 
provide access to records by affected employees and their designated 
representatives. The final rule, at paragraph (v)(2) and (v)(3), 
corrects this oversight.
    Summary. After a review of the rulemaking record, OSHA has decided 
in the final rule to retain the proposed 3-year (or until replaced by 
an updated record) retention periods for most of the required program 
records. The record, as discussed above, contains a wide range of 
opinion about the appropriate retention period for these records. OSHA 
was not convinced to change the required retention periods either by 
comments in favor of very short retention periods (see, e.g., Ex. 30-
3765, which recommends a 90-day comment period) or those arguing for a 
retention period of 30 years or more (see, e.g., Ex. 30-525).
    Records of job hazard analyses, hazard controls implemented, Quick 
Fix controls put in place, ergonomics program evaluations, and MSD 
management records must be kept for the employees and jobs covered by 
the employer's program. Further, as required by paragraph (v)(2), 
employees or their designated representative(s) must be given access to 
those records that address their report(s) of MSD incidents and the 
employer's response(s) to those reports.

Paragraph (w)--When Does This Standard Become Effective?

    In paragraph (w) of the final rule, which corresponds to 
Sec. 1910.941 of the proposal, OSHA establishes the date when the final 
rule becomes effective. The effective date is the date from which the 
compliance deadlines in this section are counted.
    In the proposal, OSHA stated that the ergonomics standard would 
become effective 60 days after the publication date of the final rule. 
OSHA stated that this period would provide sufficient time for 
employers to review the final rule, get assistance, and prepare to meet 
the initial requirements of the standard as it applied to them.
    The proposed effective date section elicited few comments. Some 
rulemaking participants (see, e.g., Exs. 30-3686, 32-85-3, Tr. 13132) 
agreed with the 60-day effective date. Other commenters (see, e.g., 
Exs. 30-74, 30-3765) felt that 60 days was insufficient. For example, 
the Dow Chemical Company (Ex. 30-3765, p. 118) urged OSHA to change the 
effective date to 180 days so that companies with existing programs, 
like Dow, would have sufficient time to review and make any necessary 
changes prior to the standard becoming effective.
    OSHA understands that employers with existing programs will need 
time to review their programs, either to establish that they qualify 
for ``grandfather'' status under paragraph (c) or to modify their 
programs to match the requirements of the final rule. However, OSHA 
believes that the 60-day date before the final rule takes effect, 
together with the additional time allowed for the implementation of the 
ergonomics program elements, will allow sufficient time for this 
purpose. Moreover, any further delay would unnecessarily deprive 
employees of needed protections against MSDs.
    George Nagle, the Corporate Senior Director of Environmental Health 
and Safety for the Bristol-Myers Squibb Company (Ex. 31-302, p. 1, Tr. 
10519-10521) suggested that a pilot program of at least one year should 
be implemented in OSHA's national and regional offices prior to 
attempting to impose a final ergonomics rule on the regulated 
community. However, there was insufficient detail in the suggestion to 
determine how such a program would work, or whether such a pilot 
program strategy would be beneficial to employees. In addition, there 
was little or no support in the record for the implementation of such a 
pilot program. OSHA believes that a significant number of companies 
have successfully implemented an ergonomics program already; the 
economic analysis estimates that approximately 20 percent of general 
industry companies have done so. Although it does not believe a pilot 
program is necessary, OSHA does intend to provide extensive compliance

[[<strong>Page</strong> 68424]]

outreach to industry when the standard is published, and has included 
useful compliance information in the Appendices to this rule. After 
reviewing the record on this issue, OSHA has concluded that the 60-day 
effective date is appropriate and sufficient for employers to read and 
understand their obligations under this final rule.

Compliance Time Frames

    OSHA's approach to compliance deadlines in the proposal differed 
from that in other OSHA standards. First, OSHA proposed a long start-up 
period so that employers would have time to get assistance before the 
compliance deadline. Second, even after the compliance deadlines, OSHA 
proposed to give employers newly covered by the standard (e.g., 
employers whose employees develop MSDs after the compliance deadlines 
have expired) additional time to set up an ergonomics program and 
implement controls. Third, OSHA proposed to allow employers to 
discontinue large portions of their ergonomics programs if no MSDs were 
reported for a specified period of time.

Paragraph (x)--When Must I Comply With the Provisions of the Standard?

    In paragraph (x) of the final rule, which corresponds to proposed 
Sec. 1910.942, OSHA establishes deadlines for compliance with the 
requirements of the ergonomics standard.
    In the proposed rule, OSHA allowed for start-up times for employers 
to set up the ergonomics program and implement controls in problem 
jobs. The proposal would have required the employer to implement MSD 
management promptly when an MSD was reported; to set up management 
leadership, employee participation, and hazard information and 
reporting within 1 year of the effective date of the final rule; to 
implement job hazard analysis, interim controls, and training within 2 
years of the effective date of the final rule; and to implement 
permanent controls and conduct program evaluation within 3 years of the 
effective date of the final rule. The proposed start-up times thus 
ranged from 1 to 3 years.
    Based on an evaluation of the comments received on the proposed 
compliance dates, OSHA has revised them in the final rule. The 
compliance deadlines in the final rule are staggered, as they were in 
the proposal, although some dates fall earlier and some later than they 
did in the proposal. Comments received on the proposed dates, and 
OSHA's response to the comments, are discussed below.
    Like the proposal, the final rule recognizes that employers need to 
begin setting up their ergonomics program soon after the rule is issued 
so that they will have an effective process in place in time to meet 
the compliance deadlines. Without phased-in start-up periods, some 
employers might wait until the last minute to take action. The final 
rule's phased-in compliance periods are also designed to ensure that 
employees who report MSD signs and symptoms are provided with prompt 
intervention (both MSD management and work restrictions) in order to 
help resolve the problem quickly and without permanent damage to the 
employee. The phase-in approach taken by the Agency was supported by 
commenters, such as the AFL-CIO, which stated that ``the overall 
timeframes for compliance * * * are more than sufficient'' (Tr. 3488).
    Finally, the longer start-up periods will also allow employers to 
integrate needed job modifications into their regular production 
schedules or processes. The best way to control MSD hazards is often in 
the design process; allowing additional compliance time allows 
establishments of all sizes to make needed changes to their processes 
as part of regular production changes, and perhaps to make those 
changes at less cost. The final rule allows an initial period of 4 
years for employers to implement permanent controls.
    The proposal envisioned two levels of ergonomics programs: a basic 
program for manual handling and manufacturing jobs (which included 
management leadership, employee involvement, hazard information, and 
employee reporting of MSD signs and symptoms) and a full program for 
employers whose employees developed work-related MSDs that were covered 
by the standard. The full program would have included all of the 
elements of the basic program plus job hazard analysis, job controls, 
training, and program evaluation. Employers who had manufacturing or 
manual handling jobs in their establishments would have had one year 
from the effective date of the rule to comply with the basic program 
requirements, and later compliance deadlines for other requirements of 
the full program (job hazard analysis, job controls, training, and 
program evaluation, if a covered MSD is reported).
    OSHA has simplified the scope of the final rule by eliminating the 
distinction between manual handling and manufacturing jobs and other 
jobs. Accordingly, the phased-in compliance deadlines for manual 
handling and manufacturing jobs found in the proposal do not appear in 
the final rule (see the summary and explanation for paragraph (b)).
    Like the proposal, the final rule does not contain different 
compliance deadlines for small and large employers. This is the case 
because OSHA believes that the compliance deadlines allow enough time 
even for very small employers to obtain information about the rule and 
ways to implement an ergonomics program. OSHA also believes that the 
final rule's 4-year phased-in compliance period for controls is 
adequate for larger employers who might have more complex processes, 
employees, problem jobs, and controls to implement.
    Some rulemaking participants (see, e.g., Exs. 30-3813, 30-3826) 
stated that the compliance dates in the proposal were logically 
inconsistent and needed to be rewritten. These commenters found this 
section on phased-in dates for program requirements to be difficult to 
follow and confusing.
    Some commenters (see, e.g., Exs. 32-339-1, 182-1, Tr. 383-384) 
noted that under the compliance deadlines set forth in the proposal, 
some employees with MSDs who had already been removed from their job 
might be returned to the problem job before the proposal required the 
employer to implement interim controls. OSHA agrees that this could be 
the case in some circumstances and has revised the final rule 
accordingly.
    The compliance time frames in the final rule have been modified as 
follows: paragraph (x)(1) gives the employer 9 months after the 
standard becomes effective (60 days after promulgation) to provide the 
information required in paragraph (d) to employees. This includes 
information about MSDs and their signs and symptoms and how to report 
MSDs as well as the kinds of risk factors, jobs and work activities 
associated with MSDs (see preamble discussion for paragraph (d) for a 
more complete discussion of the information required to be 
disseminated).
    The rest of the compliance time frames are presented in paragraph 
(x)(2), Table 2. After an employee reports an MSD (or signs or symptoms 
of an MSD), the employer must determine whether the MSD is work 
related, whether it requires a work restriction and, where appropriate, 
whether the employee's job meets the standard's Action Trigger (see the 
preamble discussions for paragraphs (e) and (f) for further details on 
these requirements). If an employer determines that an MSD incident has 
occurred (i.e., a work-related MSD that requires medical treatment 
beyond first

[[<strong>Page</strong> 68425]]

aid or restricted work, or MSD signs or symptoms that last for 7 
consecutive days) (see definition of MSD incident), then the employer 
has 7 days in which to determine whether the employee's job meets the 
Action Trigger (defined in paragraph (f) of the standard). If the 
employee's job meets the Action Trigger, then the employer has 7 days 
in which to initiate MSD management, which includes access to a Health 
Care Professional (HCP), an evaluation of the employee's condition, any 
appropriate work restrictions (including WRP for up to 90 days) (see 
preamble discussion of paragraphs (p), (q), (r), and (s) for further 
details of the employer's MSD management responsibilities). If the 
employee's job meets the Action Trigger, the employer has 30 days in 
which to initiate the management leadership element of the program 
(assign responsibility for setting up and managing the ergonomics 
program and communicating with employees about the ergonomics program) 
and the employee participation element (ensuring that employees have 
ways to report and receive prompt responses to reported MSDs and have 
ways in which to be involved in the development and implementation of 
the ergonomics program) (see preamble discussions for paragraphs (h) 
and (i) for further details of these requirements).
    Within 45 days of determining that a job meets the Action Trigger, 
the employer must train employees in setting up and managing the 
ergonomics program (see preamble discussion for paragraph (t) for 
further details of this requirement). Also, a job hazard analysis of 
the problem job must be initiated within 60 days of a determination 
that the job meets the Action Trigger (see preamble discussion of 
paragraph (j) for further details of this requirement). Within 90 days 
after a determination that a job meets the Action Trigger, the employer 
must implement interim controls and initiate training for employees, 
supervisors and team leaders involved in the ergonomics program (see 
preamble discussion of paragraphs (t) and (m)(2) for further details on 
these requirements).
    Finally, the employer must implement permanent hazard controls to 
fix a problem job (so that any MSD hazards presented by the job no 
longer are likely to cause MSDs that result in work restrictions or 
medical treatment beyond first aid) within 2 years of a determination 
that a particular job meets the Action Trigger. The final rule allows 
the employer up to 4 years (after a determination that a job meets the 
Action Trigger) for initial implementation of the permanent controls 
provisions (see preamble discussion of paragraph (m)(3) for further 
details of this requirement). The final standard has kept the proposed 
requirement to evaluate the effectiveness of the ergonomics program 
within 3 years (after a determination that a job meets the Action 
Trigger) and to promptly correct any deficiencies in the program that 
the evaluation reveals (see preamble discussion of paragraph (u) for 
further details of this requirement).
    Therefore, the effective date section in the final rule has been 
modified to avoid the unwanted results some commenters (see, e.g., Exs. 
30-3813, 30-3826) pointed out might have occurred under the proposal's 
compliance dates. For example, these commenters noted that, an employee 
with a work-related MSD could, under the proposal, be returned to a 
problem job before the employer was required to implement interim 
controls for that job. In the final rule, the employer has a longer 
period than in the proposal--up to 9 months from the effective date of 
the rule--to disseminate information to employees about MSDs. After 
that date the employer must respond promptly to any reported MSDs by 
taking steps to determine if the employee has suffered an MSD incident 
(a determination that the MSD is work-related, is persistent, and 
requires medical treatment beyond first aid, days away from work or 
restricted work). Once it is determined that an MSD incident has 
occurred, the employer has 7 days to determine if the employee's job 
meets the Action Trigger. If the job meets the Action Trigger, all of 
the other requirements of the standard spring from the date of the 
Action Trigger determination, and interim controls would need to be 
implemented within 90 days of this determination. Therefore under the 
final rule, an employee on work restriction or WRP would not have to 
face the possibility of returning to an ``unfixed'' job because the WRP 
period has expired before the employer has a duty to implement at least 
interim controls.
    Some rulemaking participants (see, e.g., Ex. 32-339-1, Tr. 3488-
3489) observed that the compliance deadline for management leadership 
and employee participation in the proposal fell due before the deadline 
for training. Commenters (see, e.g., Ex. 500-218) were concerned that 
this phase-in discrepancy would mean that employees would not be able 
to fully participate in the ergonomics program because they had not had 
training. Although the proposal would not have prevented employers from 
training employees prior to the 2-year deadline articulated in the 
proposal, OSHA has modified the deadlines for the training requirements 
in the final rule to address this concern. The final rule separates the 
employer's training obligations into segments (with the awareness 
training required by paragraph (d) given earlier than the training 
triggered by the Action Trigger). As noted, the final rule includes 
some employee awareness training for all general industry employees; 
the requirement to provide this training is the first requirement of 
the standard to go into effect after the effective date. In addition, 
paragraph (h), management leadership, and paragraph (i), employee 
participation, have training components (e.g., information on MSDs, 
information on the ergonomics program and the requirement to provide 
responsible persons with the information and resources necessary to 
meet their responsibility under the program).
    Some rulemaking participants (see, e.g., Exs. 30-3813, 30-3826) 
complained that the terms ``permanent'' and ``interim'' controls used 
in the effective date section were undefined. Definitions of 
``interim'' and ``permanent'' controls have been included in the final 
rule to further clarify the compliance obligations set forth in the 
effective date section (see paragraphs (k)(1)(i) and (m)(2)).
    A number of commenters (see, e.g., Exs. 30-3745, 30-3913, Tr. 7745-
7746, Tr. 16471) felt that the time periods for compliance given in the 
proposal were inadequate. For example, the National Telecommunications 
Safety Panel (Ex. 30-3745, pp. 16-17) stated:

    Based on previous discussions of individual program elements 
within the proposed rule, the Panel believes it would be necessary 
for employers with more than 10 worksites and 2500 employees across 
those multiple worksites to have two years after a rule becomes 
effective to implement ``management leadership'' and ``hazard 
information and reporting'' as defined in the rule, three years to 
implement ``job hazard analysis,'' ``interim controls,'' and 
training, and four years for ``permanent controls'' and ``program 
evaluation.'' This reflects the distinct probability that most 
telecommunications companies will maintain a corporate ergonomics 
program to ensure consistency of compliance, adequate communications 
and sharing of ``best practices'' across all of their workplaces.

    The National Council of Agricultural Employers (Ex. 30-3781) 
indicated that small employers needed a longer phase-in period, which 
would allow them to take advantage of innovations undertaken by larger 
companies. However, this commenter neither stated what length of time 
would be appropriate for small employers nor

[[<strong>Page</strong> 68426]]

whether more time was needed to comply with all of the provisions of 
the standard or just the interim and permanent control provisions. OSHA 
also notes that agricultural employment is not covered by this rule 
(see the summary and explanation for paragraph (b)). OSHA concludes 
that the times given to comply with the program elements in the final 
rule are adequate for all employers, including small employers, who 
will be able to avail themselves of all of the compliance assistance 
materials OSHA is disseminating, the OSHA consultation program, and 
other ergonomic resources available.
    A number of other comments were received in response to the 
compliance date section of the proposal. One rulemaking participant 
(Ex. 30-3913) argued that training should be phased-in over 5 years 
rather than the proposed 3 years because at present commercially 
available ergonomic training materials are of inadequate quality and 
more time would be needed to improve the overall quality of such 
training materials. OSHA concludes that a wealth of material is already 
available that can assist in meeting the training obligations in the 
final rule. (See Docket 777, e.g., ``Ergonomics Awareness Manual (Ex. 
32-185-3-11);'' ``Trainer's Manual Ergonomics Program (32-111-1-21).'') 
In addition even more training materials will become available through 
OSHA outreach as well as the market for such materials which the 
promulgation of this rule will create. Further, the training 
obligations in the final rule are implemented over time, and the 
materials for them can thus be developed and implemented piecemeal as 
program development occurs within the workplace.
    Some participants (see, e.g., Exs. 30-3922, 30-3032, 30-3284, 30-
3922, 32-133-1, 32-300-1, L30-5088, 601-x-1711) thought that the 
deadlines for interim or permanent controls were too short. Others 
(see, e.g., Exs. 30-526, 30-710, 30-2433) felt that any deadline for 
implementing permanent controls was unrealistic, due to the difficulty 
of providing permanent controls. For example, Pinnacle West Capital 
Corporation (Ex. 30-3032, p. 12) stated:

* * * due to the heavy regulation of the plant modification process 
by the Nuclear Regulatory Commission in electric utility nuclear 
plants, it is entirely possible that some engineering control 
implementation could take more than the [proposed] three year 
permanent control deadline. This is particularly true if the 
modification can only be accomplished during plant outage times.

    This commenter did not indicate how often such plants are off line; 
however, OSHA notes that the inability of an employer to comply for 
reasons of infeasibility can always be raised in the context of 
enforcement. The fact that an employer may confront a highly unusual 
situation, such as the one this commenter describes, is no reason for 
the implementation dates for all employers to be extended. Another 
participant stated that the brick-making industry would have problems 
meeting the proposed three-year phase-in period for permanent controls 
(Tr. 7745-7746) because they believe that the only permanent controls 
for their ergonomics problems is automation. OSHA notes that this 
commenter reported making substantial progress in reducing its MSD 
hazards, but recognizes that feasibility may be an issue for some 
establishments.
    The American Industrial Hygiene Association (AIHA) (Tr. 16471) 
noted difficulties that might be encountered in meeting the proposed 
compliance deadlines for the implementation of interim or permanent 
controls by stating that ``[i]n some cases, substantial reductions in 
hazards may require reworking an entire material handling system for 
even a production line. These types of changes usually require a stage 
process that may run over three years.'' Again OSHA understands that 
controls can take some time to implement in certain complex cases, and 
further that many companies prioritize their jobs for control. OSHA's 
compliance staff is trained to address these issues on a case-by-case 
basis, and will do so in enforcing this standard as well.
    OSHA has determined that, except in rare cases, employers will be 
able to meet the compliance deadlines in the final rule. These 
deadlines are based on a review of the record on the appropriateness of 
the proposed time given to implement permanent controls. As a result of 
that review, OSHA has increased the amount of time employers are 
allowed to implement permanent controls initially to 4 years after the 
final rule goes into effect, and to 2 years thereafter. This means that 
the 4-year period is the maximum time that any employer can take to 
implement permanent controls. In other words, the employer has 4 years 
after the effective date to install permanent controls or 2 years after 
the employer determines that a job meets the Action Trigger, whichever 
is later. For example, if an employer determines that a job meets the 
Action Trigger 1 year after the effective date, that employer will then 
have 3 years to install permanent controls. On the other hand, if the 
employer makes the Action Trigger determination 3 years after the 
effective date (or 4 years or 5 years after), that employer has 2 years 
from that date to install permanent controls. This two-tiered approach 
to the requirement to implement permanent controls initially was 
adopted to allow employers sufficient time to deal with a possible 
increase in the number of MSD incidents soon after the standard becomes 
effective. The Agency believes, once the standard has been in effect 
for several years, there will be fewer MSD incidents, and that a 
shorter compliance deadline for permanent controls--2 years--will give 
these employers sufficient time to implement permanent controls for 
problem jobs.
    The few employers who may find the generous compliance times given 
in the final rule inadequate also may avail themselves of the temporary 
variance procedures provided in the Occupational Safety and Health Act 
of 1970.
    Many commenters felt that the compliance deadlines were too long 
(see, e.g., Exs. 30-2039, 30-2116, 30-2825, 30-2847, 30-3001, 30-3033, 
30-3034, 30-3035, 30-3258, 30-3259, 30-30-3332, 30-3686, 30-4159, 30-
4534, 30-4536, 30-4546, 30-4547, 30-4548, 30-4549, 30-4562, 30-4627, 
30-4776, 30-4800, 30-4801, 31-242, 31-353, 32-85-3, Tr. 11196, 13133).
    Typical of comments stating that the deadlines were too long was 
that of the American Nurses Association (ANA) (Ex. 30-3686, p. 22), 
which criticized the deadlines on the grounds that they were so long 
that they would continue to permit opportunities for thousands of 
nurses and HCWs (health care workers) to be injured. Although the 
immediate implementation of effective controls on jobs with MSD hazards 
would be ideal, OSHA recognizes that employers will need time to find, 
implement, and analyze the effectiveness of controls for each job. OSHA 
has modified the compliance time frames to address comments such as the 
ANA's by significantly shortening the amount of time allowed in the 
final rule for employers to address jobs that meet the Action Trigger. 
In the final rule, for example, interim controls must be implemented 
within 90 days of a determination that a job meets the Action Trigger, 
as opposed to the 2 years given in the proposal. Further, the deadlines 
in the final rule represent the maximum amount of time employers will 
have to comply with the elements of the ergonomics program. Employers 
are encouraged to implement effective controls as soon as possible, and 
OSHA believes that many employers will do so, because this approach 
will benefit both employers and employees by

[[<strong>Page</strong> 68427]]

reducing the number and gravity of MSD injuries.
    Other commenters supported the proposed time frames. For example, 
the AFL-CIO (Tr. 3488) stated ``[t]he overall time frames for 
compliance we think are more than sufficient, particularly given that 
the standard has been under development for so long.'' OSHA understands 
that the compliance deadlines given are generous, but has concluded 
that some companies will need the extra time to work needed job 
modifications into their regular production change schedules. From a 
review of the comments on this section, OSHA has determined that the 
final rule strikes a rational balance between the need to respond with 
due speed to MSD incidents and the benefits of developing remedies to 
problem jobs in an orderly fashion. Substantial evidence in the record 
supports the compliance time frames adopted in the final rule.
    The Communications Workers of America (CWA) (Tr. 13133) supported 
the requirement for prompt responses to reported MSDs, but felt that 
the remaining requirements (management leadership and employee 
participation, hazard information and reporting, job hazard analysis, 
training, interim and permanent controls, and program evaluation) 
should all begin one year after the effective date of the standard. The 
CWA (Tr. 13133) also stated that hazard information training should be 
conducted within 30 days after the identification of a problem job. In 
the final rule, this initial training is required before the 
identification of a problem job. The CWA also suggested that 
comprehensive training on MSD hazards, controls, and the employer's 
ergonomics program should be required 90 days after the identification 
of a problem job. As noted above, in the final rule, all of the 
training requirements go into effect within 90 days of a determination 
that a job meets the Action Trigger. Several training requirements, 
such as the dissemination of MSD awareness information to employees 
(paragraph (d)) and the training of employees involved in setting up 
the ergonomics program (paragraph (t)) have to be met substantially 
sooner.
    Some commenters agreed that MSD management should be provided 
immediately, or as soon as possible (see, e.g., Exs. 30-2387, 30-4538, 
31-105, 31-106, 31-129, 31-170, 31-229, 31-276, 31-309, Tr. 13133). 
Other participants (see, e.g., Exs. 30-74, 30-2987) felt that the 
requirement for prompt response, i.e., as soon as an MSD is reported 
after the effective date, could be disruptive and would result in an 
employer having insufficient time to prepare for the implementation of 
the overall ergonomic program requirements. The American Health Care 
Association (AHCA) (Ex. 30-2987) recommended at least a 1-year delayed 
effective date for MSD management. The AHCA stated ``[b]ecause we 
anticipate that MSDs will be reported early under this proposed 
standard, we envision that the MSD management component deadline will 
occur almost immediately after the 60-day start-up. This hardly 
provides an opportunity for employers to receive assistance on MSD 
management * * * '' In the final rule, the dates in the proposal have 
been modified to clarify that, although the employer has 11 months from 
the time the standard is published to disseminate information about 
MSDs (including their signs and symptoms and how to report them), the 
employer need not respond to the employee reports initially until the 
11-month period has passed. This initial delay in employer response 
obligations is necessary to permit the employer to develop an ergonomic 
program in an orderly fashion.
    Some commenters felt that after the standard became effective 
employers should be given 5 days to respond to MSD reports (see, e.g., 
Exs. 30-400, 30-4837, 31-3, 31-12, 31-113, 31-31-150, 31-160, 31-186, 
31-187, 31-192, 31-200, 31-205, 31-243, 31-307, 31-347); others thought 
that 2 days would be appropriate (Ex. 31-23). These commenters only 
provided their opinions in this matter, without detail. Other periods 
of time were also recommended for MSD management deadlines, such as 1 
month (Exs. 31-125, 31-265 ), again without detailed explanation. The 
proposal (Sec. 1910.942) had merely required that the employer provide 
a ``prompt'' response. This requirement has remained essentially the 
same in the final rule but has been included in paragraph (e) rather 
than in the effective date section (see preamble discussion of 
paragraph (e) for a more detailed discussion of the MSD response 
requirements).
    Some commenters (see, e.g., Exs. 31-27, 31-78, 31-170, 31-180) 
argued that medical treatment deadlines for MSDs are addressed in state 
workers' compensation laws and that OSHA should not interfere with 
those requirements. These commenters misunderstand the rule's MSD 
management provisions. The OSHA rule does not require employers to 
obtain medical treatment for employees with MSDs; OSHA assumes that 
MSDs will continue to be treated under the workers' compensation 
system, as they have been. The MSD management required by the standard 
requires the employer to provide access to an HCP, if the employee 
wishes access, solely for the purposes of evaluation and follow-up and, 
if necessary, work restrictions. The MSD management system required by 
the standard does not in any way interfere with workers' compensation 
(see preamble discussion of paragraph (q)). OSHA included the MSD 
management provisions pursuant to its statutory authority under the OSH 
Act (see preamble discussion of paragraph (r)). After reviewing a wide 
variety of opinions as to how long injured employees should wait before 
receiving MSD management, OSHA has concluded that MSD management should 
begin within 7 days after a determination can be made that an MSD 
incident, as defined by this standard, has occurred. Compliance dates 
are necessary to effectuate the MSD management provisions included in 
the standard, and OSHA believes that the time frames included in the 
final rule for MSD management are appropriate and supported by the 
record.
    In Sec. 1910.943, OSHA proposed to establish different compliance 
time frames for those employers who had not identified a problem job 
until after some or all of the start-up compliance deadlines 
established in proposed Sec. 1910.942 had passed. This was because the 
occurrence of an MSD incident is difficult to predict and may not 
occur, in some establishments, for many years, i.e., long after the 
standard's initial start-up dates have run.
    In proposed Sec. 1910.943, if an employer incurred a compliance 
obligation after the compliance start-up deadline for that obligation 
had passed, a different timetable applied. OSHA's reasons for this 
timetable, which was shorter than the initial compliance timetable, was 
that employers in later years would not need as long to implement 
ergonomics programs because they could take advantage of program 
development and remedies that had been developed by other employers in 
the interim. Accordingly, proposed Sec. 1910.943 gave employers with 
later incurred compliance obligations some additional time to comply, 
but the time frame between the MSD incident and the remedy was shorter 
than that proposed for initial compliance when the standard became 
effective (see 64 FR at 66074).
    From a review of the rulemaking record, it is clear that many 
participants did not understand proposed Sec. 1910.943 or how it would 
work (see, e.g., Exs. 30-2116, 30-2809, 30-2825, 30-2847, 30-

[[<strong>Page</strong> 68428]]

3001, 30-3033, 30-3034, 30-3035, 30-3258, 30-3259, 30-3332, 30-3826, 
30-4159, 30-4534, 30-4536, 30-4546, 30-4547, 30-4548, 30-4549, 30-4562, 
30-4627, 30-4776, 30-4800, 30-4801, Tr. 3236). Additionally, this 
section of the proposed rule elicited a number of comments, most of 
which were critical (see, e.g., Exs. 32-85-3, 30-297, 30-424, 30-434, 
30-1090, 30-2433, 30-3120, 30-3171, 30-4537, 32-85-3, 500-145). 
However, few commenters provided detailed reasons for their views.
    A few commenters (see, e.g., Exs. 30-4538, 30-3686, 31-353, 32-300-
1) recommended that proposed Sec. 1910.943's requirement that MSDs be 
responded to within 5 days be modified to require MSD management 
``promptly'' when an MSD is reported. The American Federation of 
Government Employees (Ex. 30-4538, p. 8) stated:

    OSHA should require medical management sooner than five days. If 
an employee experiencing MSD symptoms continues to work in the same 
job without medical attention, his condition could get worse. In 
general, by the time an employee reports a problem, she has been 
experiencing symptoms for some time and should not have to wait 
another few days for treatment.

    Some rulemaking participants (see, e.g., Exs. 30-240, 30-526, 30-
710, 30-3813, 30-3826, 30-3284, 32-300-1, 501-6) disagreed with the 
idea of providing less time for later-year compliance in Sec. 1910.943 
than was proposed for initial compliance in Sec. 1910.942. For example, 
the Department of Defense (Ex. 30-3826, p. 11) stated ``[i]t is not 
clear why two timetables are provided. It seems capricious to allow 
some employers up to three years to fully implement their ergonomics 
programs, while others will have only one year.''
    Another rulemaking participant (Ex. 32-229-1) observed that the 
proposed deadline for training expires after the deadline for 
management leadership and employee participation, which would mean that 
employees would not be trained before they are expected to participate. 
In response, OSHA has shortened the deadline for training for employees 
who are involved in setting up and managing the ergonomics program in 
the final rule from the proposed 90 days to 45 days after the employer 
has determined that a job meets the Action Trigger. Employee 
participation has a deadline of 30 days after the employer has 
determined that the job meets the Action Trigger.
    As noted earlier, in the final rule, the events that trigger an 
employer's obligations under this standard have been modified since the 
proposal. All employers covered by the ergonomics standard must comply 
with the minimal requirements in paragraph (d) (informing employees) 
within 11 months of the publication of the rule. The remainder of the 
rule's obligations and time frames for complying with the various 
requirements are incurred after a determination that an MSD incident 
has occurred in a job that meets the Action Trigger set forth in 
paragraph (f). In view of this altered approach in the final rule, it 
is no longer necessary to provide two separate compliance time frames 
as was done in the proposal.

Paragraph (y)--When May I Discontinue my Ergonomics Program for a Job?

    Paragraph (y) allows employers to discontinue most elements of 
their ergonomics program for a job if the risk factors in that job have 
been reduced to levels below those in the Basic Screening Tool (Table 1 
of the standard). The only obligations the employer continues to have 
for jobs that have been controlled to that level are to maintain the 
controls that reduce the risk factors, continue to provide the training 
related to those controls, and keep records of the job hazard analysis 
and the controls implemented for that job.
    OSHA proposed to allow employers to discontinue portions of their 
ergonomics program when no covered MSD had been reported in a problem 
job for 3 years after the problem job was controlled. Paragraph (y) of 
the final rule has the same advantages as the proposed provision, but 
has been revised to reflect changes made to the design of the final 
rule. That is, the approach taken in the final rule recognizes the role 
of the Basic Screening Tool in Table 1, which acts, along with the 
report of an MSD incident, as a trigger for action under the standard 
and, in paragraph (y), as the mechanism for relieving employers of most 
of their obligations under the standard.
    Some rulemaking participants (see, e.g., Exs. 30-526, 30-710, 30-
3686, 31-242) argued that the 3-year timetable for discontinuing 
elements of the program should be eliminated. These commenters felt 
that employers with ergonomics programs should be required to maintain 
all elements of their ergonomics program indefinitely.
    Commenters took issue with the proposed timetable for discontinuing 
parts of the program; some thought the time period was too short, while 
others argued that it was too long. For example, one rulemaking 
participant (Ex. 32-185-3) stated that 3 years is too soon to 
discontinue parts of the ergonomics program, because it gives 
insufficient time for employers to accurately determine if the controls 
implemented have been effective. However, this commenter did not 
suggest what amount of time would be appropriate to wait before 
discontinuing parts of the program.
    On the other hand, some rulemaking participants (see, e.g., Exs. 
30-3471, 30-4185, 30-3868, Tr. 3325-3326) thought that 3 years was too 
long to wait before discontinuing certain aspects of the program. For 
example, Tyson's Foods (Ex. 30-4185, p. 26) stated ``* * * OSHA has set 
an unrealistically * * * low threshold * * * by premising the 
obligation to implement engineering controls on the existence of * * * 
a single reported MSD and then further requiring employers to continue 
to search for and implement engineering controls until there are no 
more MSDs for at least three years * * *''
    Other commenters (see, e.g., Exs. 30-3344, 30-3749, 30-4674, Tr. 
3325-3326, Ex. 601-x-1710) recommended using alternative criteria for 
discontinuing elements of the program. For example, Abbott Laboratories 
(Tr. 3325-3326) stated ``clearly the bar for ending the full program is 
too high. We propose that OSHA substitute a performance-based 
replacement for the `one MSD in three years' criterion.'' OSHA has 
considered this suggestion but has determined that such a performance-
based approach, such as the use of industry averages, would be too 
complex to apply and too difficult to verify during enforcement.
    Some commenters (see, e.g., Exs. 30-2116, 30-2825, 30-2847, 30-
3001, 30-3035, 30-3258, 30-3259, 30-4159, 30-4534, 30-4536, 30-4546, 
30-4547, 30-4548, 30-4549, 30-4562, 30-4627, 30-4801, 32-85-3, 
Tr.13134) stated that the proposed rule would permit employers to 
discontinue too many elements of the ergonomics program. The 
Communications Workers of America (Tr.13134), for example, stated that 
management leadership and employee participation, hazard information 
and reporting, awareness training, program evaluation, and maintenance 
of controls and the training related to those controls should be 
continued to ensure the control or prevention of MSDs.
    OSHA has considered the possibility of increasing the number of 
program elements employers are allowed to discontinue if they have 
reduced the MSD hazards in jobs covered by the standard to levels below 
those in the screen (Basic Screening Tool in Table 1). However, the 
Agency has decided that maintaining the controls that allowed the 
employer to control the job,

[[<strong>Page</strong> 68429]]

continuing the training in the use of those controls for employees in 
these jobs and keeping records of the job hazard analysis and controls 
for that job are the minimum requirements needed to ensure employee 
protection. These are the only program requirements the employer is 
required to continue once the risk factors in the job have been reduced 
to levels below the screen.
    Paragraph (y) contains no time period and no link to the occurrence 
of MSD incidents, as the proposal did. Instead, both the ``entrance'' 
to and ``exit'' from most program obligations is tied to the extent of 
the risk factors in the job, as indicated by the screen.

Paragraph (z)--Definitions

    Paragraph (z) of the final rule contains a number of definitions of 
terms used in this final rule. Most of the definitions are 
straightforward and self-explanatory. A general discussion of each of 
the terms can be found below; however, clarification of many of the 
terms is provided in the summary and explanation sections for the 
provisions where the terms are used. OSHA believes that describing 
terms where they are used makes it easier for employers and employees 
to understand what OSHA means when it uses them.
    The following terms are defined in the final rule: ``administrative 
controls,'' ``Assistant Secretary,'' ``control MSD hazards,'' 
``Director,'' ``employee representative,'' ``engineering controls,'' 
``follow-up,'' ``health care professionals (HCPs),'' ``job,'' 
``musculoskeletal disorder (MSD),'' ``MSD hazard,'' ``MSD incident,'' 
``MSD signs,'' ``MSD symptoms,'' ``personal protective equipment,'' 
``problem job,'' ``risk factor,'' ``work related,'' ``work practices,'' 
``work restriction protection (WRP),'' ``work restrictions,'' and 
``you.''
    Several terms were defined in the proposal (64 FR 65864 and 64 FR 
66075) but are not defined in the final rule: ``covered MSD,'' 
``eliminate MSD hazards,'' ``ergonomics,'' ``ergonomic design,'' 
``ergonomic risk factors,'' ``have knowledge,'' ``manual handling 
jobs,'' ``manufacturing jobs,'' ``materially reduce MSD hazards,'' 
``MSD management,'' ``no cost to employees,'' ``OSHA recordable MSD,'' 
``periodically,'' ``persistent MSD symptoms,'' ``physical work 
activities,'' and ``resources.'' These terms are either not being used 
in the final rule, have been replaced by other terms that are defined 
(either in this paragraph or where they first appear), or have such 
clear meanings that further definition is unnecessary.

General Comments on Definitions

    OSHA received many comments on the definitions for terms used in 
the proposed ergonomics program standard. A great deal of comment 
focused on the perceived vagueness of the terms and definitions, with 
commenters raising concerns about their inability to understand these 
terms and, thus, their ability to comply appropriately. Others raised 
concerns about the cost of compliance, arguing that they would spend 
large sums of money trying to comply because they were unsure what the 
rule meant (see, e.g., Exs. 32-207-1, 32-206-1, 30-3765, 30-3845, 30-
3813, 32-368-1, and 30-3853). One commenter, Monsanto Corporation (Ex. 
30-434), recommended moving the definitions to the front of the 
document for clarity. OSHA has not adopted this recommended change, 
although a Note to paragraph (a) of the rule states that the 
definitions for the standard appear in paragraph (z).
    OSHA has arranged its discussion of the comments on definitions so 
that the ``general'' comments--those that apply to all definitions--are 
discussed first, and the more specific comments--those that pertain to 
a particular term or definition--are discussed afterward. Additional 
discussion of some terms can be found in the summary and explanation of 
the provision where the term is used.
    On the overall issue of the vagueness of the definitions, 
commenters said that terms were unclear or too broadly defined, which 
would make it difficult for them to implement the standard (see, e.g., 
Exs. 30-294, 30-434, 30-1897, 30-3765, 30-2208-2, 30-3845, 30-1722, 30-
3813, 30-4185, 30-3739, 30-4006, 30-2705, 30-4038, 601-X-1379, 30-3889, 
30-2540, 30-4760, 30-4021, 33-1455, 30-4599, 33-1463, 33-1462, 30-2751, 
30-4982, 30-5009, 30-2598, 30-2569, 30-4149, 30-4963, 30-4222, 30-4023, 
30-4224, 30-4060, 30-4063, 30-2280, 30-3793, 30-4235, 30-2540), 500-1-
4, 500-1-5, and 500-1-28).
    The comments of the National Automobile Dealers Association are 
representative of the comments received on the general issue of the 
vagueness of the proposed definitions:

    To the extent that the ergonomics rule remains inexorably tied 
to the reporting of MSD risks, MSD symptoms, MSDs, OSHA recordable 
MSDs, and covered MSDs, [automobile] dealers will be forced to 
closely scrutinize reported MSD signs and symptoms, to screen out 
those that are not tied to real MSDs, and to avoid identifying OSHA 
recordable MSDs. To be sure, proposed section 1910.145 lists 
somewhat helpful definitions for each of these terms. Nonetheless, 
these definitions are lacking in that they fail to provide 
sufficient guidance to enable dealers to make practical, cost 
effective, and objective determinations (Ex. 4839).

    Some commenters were concerned that the terms lacked objective 
criteria (see, e.g., Exs. 32-206-1, 30-3765, 30-1722, 30-4185, 30-3826, 
30-4538, 32-300-1, 30-3336, 30-2208-1, 30-3853, 30-3749, and 30-3167). 
Some commenters suggested that OSHA should use definitions for certain 
terms that had been established by outside organizations (see, e.g., 
Exs. 30-3765, 30-4499, and 30-3167). Another commented that there was 
no consensus definition on many of the terms; that experts are not in 
agreement on the root cause and true definition of MSDs; and that 
scientists find it difficult to explain why different individuals 
working on the same job will not experience the same symptoms (Ex. 30-
3167). Some of the commenters disagreed with the way the terms were 
defined or offered suggested alternatives (see, e.g., Exs. 30-3765, 30-
4185, 30-3826, 30-2208-2, 30-1722, 32-111-4, 30-4538, 30-3934, 32-198-
4, 32-300-1, 30-2208, 30-4499, 30-3818, 30-3000, 31-242, 30-4499, 30-
3867, 30-3818 and 30-434).
    The Department of Defense (DoD) (Ex. 30-3826) suggested that OSHA 
eliminate the need for many of the definitions, such as those for 
manufacturing jobs, manual material handling, and several terms used 
within those definitions, by simply including all general industry 
employers in the scope of the standard. OSHA notes that the scope of 
the final rule has been revised so that it is no longer necessary to 
define ``manufacturing jobs'' and ``manual handling jobs.'' (See the 
summary and explanation discussion on Scope, paragraph (b).)
    Some commenters argued that the definitions' vagueness meant that 
OSHA's cost estimates would be substantially underestimated because 
employers would do ``everything'' in an attempt to comply (see, e.g., 
Exs. 32-206-1, 32-141-1 and 30-3813). Another commenter questioned 
whether the rule would result in a substantial reduction in MSDs 
because it was so unclear (Ex. 32-368-1). Others said that if the 
standard cannot be understood, it is not legally defensible, citing 
cases such as Kent Nowlin Construction Co. v. OSHRC, Connally v. 
General Constr. Co., and Diebold Inc. v. Marshall (Exs. 30-1897, 32-
206-1, 32-368-1 and 30-3336).
    In response to these comments, OSHA has redefined many terms in the 
final rule, deleted others, and provided greater clarity in several 
areas that were particularly singled out for comment

[[<strong>Page</strong> 68430]]

such as the level of control employers must reach. Revised provisions 
of the final rule that provide definite compliance endpoints and ``safe 
harbors'' for employers are examples of these changes. The issue of 
``fair notice'' (vagueness) is discussed in the section of the preamble 
entitled ``Other Statutory Issues''. Thus the final rule addresses the 
concerns of employers by providing objective criteria and establishing 
clear obligations for employers to follow.

Specific Comments on Definitions

    Administrative controls are defined as changes in the way that work 
in a job is assigned or scheduled that reduce the magnitude, frequency, 
or duration of exposure to ergonomic risk factors. Examples of 
administrative controls include employee rotation, employer-designated 
rest breaks designed to reduce exposure, broadening or varying job 
tasks (job enlargement), and employer-authorized changes in work pace.
    The definition of the term administrative controls is essentially 
unchanged from the proposal. OSHA received one comment on the 
definition (Ex. 30-3748), which noted that the proposed definition was 
clear.
    The term Control MSD hazards means to reduce MSD hazards to the 
extent that they are no longer reasonably likely to cause MSDs that 
result in work restrictions or medical treatment beyond first aid. This 
is a new term in the final rule. OSHA has included a definition for 
this term in the final rule because paragraph (k) of the standard 
requires employers to control MSD hazards. Controlling hazards means 
that the risk factors that were occurring at a magnitude, duration, or 
frequency sufficient to cause an MSD hazard have been reduced to the 
extent that they are no longer reasonably likely to cause MSDs that 
result in work restrictions or medical treatment beyond first aid. 
Employers are to use engineering, work practice, or administrative 
controls or personal protective equipment to control MSD hazards.
    The proposed rule contained two similar terms--``eliminate MSD 
hazards'' and ``materially reduce MSD hazards.'' Commenters alleged 
that these terms were vague and incapable of quantification (see, e.g., 
Exs. 30-1897, 32-206-1, 32-368-1, 30-3765, 30-1101 and 30-2986). 
Statements in the record said that the term ``eliminate MSD hazards'' 
should not be used because it is not possible to eliminate hazards so 
completely that MSDs will no longer occur. There will always be 
ergonomic risks, according to these commenters (see, e.g., Ex. 30-
3765). In addition, there were statements that the term ``eliminate MSD 
hazards'' is not really different from ``materially reduce MSD 
hazards'' (see, e.g., Ex. 32-300-1). Comments on the term ``materially 
reduce MSD hazards'' stated that employers would not be able to 
evaluate whether or not material reductions in risks have occurred and 
expressed concern that the term could be interpreted differently by 
employers, employees, and OSHA inspectors (see, e.g., Ex. 30-3845). 
Some commenters also objected to some of the phrases used in the 
proposal definition of ``materially reduce MSD hazards,'' such as 
``magnitude,'' ``likelihood,'' and ``significantly'' (see, e.g., Exs. 
30-1897, 30-3765, 30-3866, 32-300-1, 30-4467).
    In response to comments in the record, OSHA has decided to delete 
the terms ``eliminate MSD hazards'' and ``materially reduce MSD 
hazards'' from the final rule. Instead, the Agency has defined 
``control MSD hazards'' more clearly and has additionally provided 
clear compliance endpoints that essentially cure the vagueness 
objections raised.
    OSHA also received a comment from the Department of Defense (Ex. 
30-3826), which recommended that definitions be developed for 
``interim'' and ``permanent controls,'' stating:

    The timetable in [proposed] Sec. 1910.943 included reference to 
``(e) interim controls'' and ``(g) permanent controls''; however, 
there are no corresponding sections nor definitions within section 
1910.945 that discusses their distinction. At what point does an 
interim control become a permanent control, especially when the 
employer is following the incremental abatement process guidance 
contained within 1910.922. * * * According to some sources, the only 
permanent control for ergonomic hazards is an engineering control--
administrative and work practice controls can almost always be 
circumvented in the name of convenience, schedule or production. 
Unfortunately, in many cases, there are no feasible engineering 
controls for identified ergonomic hazards. Therefore, permanent 
controls must be defined, and criteria for determining whether an 
employer has fulfilled the requirement must be identified (Ex. 30-
3826).

The final rule does not use the term ``interim'' controls. The terms 
used in the standard, ``initial controls'' and ``permanent controls,'' 
are self-explanatory; they are discussed in the summary and explanation 
for paragraph (m).
    The term Employee representative means a person or organization 
that acts on behalf of an employee. This term was not defined in the 
proposal, but is included in the final rule for clarification. 
Additional discussion relating to the meaning of this term can be found 
in the summary of explanation of paragraph (i).
    Engineering controls are defined in the final rule as physical 
changes to a job that reduce MSD hazards. Examples of engineering 
controls include: changing, modifying, or redesigning workstations, 
tools, facilities, equipment, materials, or processes.
    The definition of the term ``engineering controls'' has been 
changed from the proposal. In the proposal, OSHA defined engineering 
controls as physical changes that eliminated or materially reduced the 
presence of MSD hazards, a term also defined in the proposal. OSHA 
defined the term ``materially reduce MSD hazards'' to mean ``to reduce 
the duration, frequency and/or magnitude of exposure to one or more 
ergonomic risk factors in a way that is reasonably anticipated to 
significantly reduce the likelihood that covered MSDs will occur.'' 
(See the discussion of these terms above, in the section on ``Control 
MSD hazards.'') One commenter stated that the definition of engineering 
controls was clear (Ex. 30-3748).
    The term Follow-up means the process or protocol an employer or HCP 
uses (after a work restriction is imposed) to check on the condition of 
employees who have experienced MSD incidents. The definition of the 
term ``follow-up'' is essentially the same as the proposed definition, 
except that OSHA has removed a sentence from the proposed definition 
that explained why ``follow-up'' was necessary. The sentence removed 
was ``Prompt follow-up helps to ensure that the MSD is resolving and, 
if it is not, that other measures are promptly taken.'' No substantive 
comments on this definition were received. Additional discussion 
relating to the meaning of this term can be found in the summary and 
explanation for paragraph (p).
    Health care professionals (HCPs) are physicians or other licensed 
health care professionals whose legally permitted scope of practice 
(e.g., license, registration or certification) allows them to provide 
independently or be delegated the responsibility to provide some or all 
of the MSD management requirements of this standard. This definition is 
identical to the definition in the proposed rule.
    One commenter asked OSHA to clarify the definition to specify which 
occupations (physician, nurse, physical therapist, etc.) were included 
in the term ``HCP'' (Ex. 30-74). Others were of the opinion that the 
definition was too broad (see, e.g., Exs. 30-991, 30-3004, 30-3934, 30-
3937, 30-2208 and 32-22).

[[<strong>Page</strong> 68431]]

The comments of the Combe Company are representative: ``[b]y allowing 
persons who do not even have a medical degree to diagnose and treat 
these disorders, the proposed standard creates an environment where the 
potential for misdiagnosis and improper treatment efforts is 
dramatically increased'' (Ex. 30-3004). In response to these comments, 
OSHA notes, first, that the final rule's MSD management section does 
not require the diagnosis and treatment of MSDs; these medical aspects 
of MSDs are left to the workers' compensation system, as they always 
have been. The MSD management envisioned by the standard entails the 
evaluation of an MSD to identify the need for work restrictions and 
follow-ups to ensure that recovery is progressing. Second, the Agency 
is deferring to the states on the issue of permitted scopes of 
practice; that is, different states permit different HCPs to perform 
different healthcare activities, and employers are expected to 
ascertain that the HCPs they rely on to carry out the MSD management 
responsibilities under the standard are licensed, registered, or 
certified to perform these functions.
    Commenters proposed an alternative definition of HCP, i.e., that in 
addition to requiring licensing, OSHA require HCPs to have sufficient 
training and experience in diagnosing and treating MSD injuries/
illnesses (see, e.g., Exs. 30-3934 and 30-3937). Another organization 
pointed out that because the definition is so broad, it could include 
occupations such as emergency medical technicians or licensed 
vocational nurses who would not be the appropriate professionals to 
make decisions with respect to MSDs (Ex. 30-2208). The New Mexico 
Workers' Compensation Administration argued that under the proposed 
definition, a massage therapist could render an opinion on MSDs (Ex. 
32-22). Again, OSHA is confident that the state scope of practice laws 
that govern HCPs will ensure that only appropriate personnel are 
permitted to carry out the standard's MSD management functions.
    Some commenters urged OSHA to limit the term HCP only to physicians 
on the grounds that fact finders rely heavily on treating physician's 
opinions when litigating causation issues under the various workers' 
compensation laws (see, e.g., Exs. 30-3749, 30-3344 and 30-4674). 
OSHA's medical management provisions are independent of and unrelated 
to the workers' compensation system's procedures for determining 
medical treatment, or extent-of -disability determinations (see the 
discussion in the summary and explanation for paragraphs (p), (q), (r), 
and (s)).
    The American College of Occupational and Environmental Medicine 
(ACOEM) recommended that the definition of health care professional be 
changed to ``occupational physicians or other licensed occupational 
health care professionals,'' to focus on the HCP's training and 
competencies in occupational medicine. OSHA has not revised the 
definition of HCP in this standard, although OSHA believes that many 
employers recognize and only rely on the expertise of occupational 
physicians and nurses. OSHA's more recent standards (see, e.g., the 
Respirator standard and the Methylene Chloride standard) have used the 
term HCP, and have defined it in the same way as in this ergonomics 
standard; changing it would thus be inconsistent with recent usage. The 
other issues raised by ACOEM--such as the kinds of activities 
encompassed by the term MSD management--are discussed in the summary 
and explanation for that paragraph (paragraph p).
    The American Society of Safety Engineers (ASSE) (see, e.g., Ex. 30-
386) asked OSHA to include a definition of ``safety professionals'' in 
the rule and to acknowledge the important role of these professionals 
in ergonomics programs. The preamble to the final rule does so, and 
specifically mentions the role of safety professionals, industrial 
hygienists, and other safety and health professionals in ergonomics 
program implementation.
    The term Job is defined in the final rule to mean the physical work 
activities or tasks that an employee performs. For the purpose of this 
standard, OSHA considers jobs to be the same if they involve the same 
physical work activities or tasks, even if the jobs that require those 
activities or tasks have different titles or job classifications. OSHA 
is retaining the definition for the term ``job'' unchanged from that in 
the proposed rule, except for the addition of the word ``tasks''.
    Comments on the definition of ``job'' in the proposal stated that 
the definition gave little guidance on how employers were to determine 
whether jobs were the same (Ex. 30-3784) and that OSHA should change 
the word ``job'' or ``job based'' to ``task'' or ``task based'' (Exs. 
30-3765 and 30-3826). The Department of the Navy (Ex. 30-3818) also 
recommended that OSHA focus on job tasks rather than the job because 
the term ``job'' is frequently associated with titles and position 
descriptions. The Department of the Navy also asked OSHA to define the 
word ``task'' in the final rule. OSHA believes that the final rule's 
definition of a job as the physical activities or tasks that an 
employee performs is responsive to the Navy's concerns. For a 
discussion of the meaning of tasks in the context of job hazard 
analysis, see the summary and explanation for paragraph (j). In 
addition, the presence of the Basic Screening Tool will enable 
employers to identify jobs that are the same, despite, for example, 
differences in job titles.
    Musculoskeletal disorders (MSDs) is defined in the final rule as:

a disorder of the muscles, nerves, tendons, ligaments, joints, 
cartilage, blood vessels, or spinal discs. For purposes of this 
standard, this definition only includes MSDs in the following areas 
of the body that have been associated with exposure to risk factors: 
neck, shoulder, elbow, forearm, wrist, hand, abdomen (hernia only), 
back, knee, ankle, and foot. MSDs may include muscle strains and 
tears, ligament sprains, joint and tendon inflammation, pinched 
nerves, and spinal disc degeneration. MSDs include such medical 
conditions as: low back pain, tension neck syndrome, carpal tunnel 
syndrome, rotator cuff syndrome, DeQuervain's syndrome, trigger 
finger, tarsal tunnel syndrome, sciatica, epicondylitis, tendinitis, 
Raynaud's phenomenon, hand-arm vibration syndrome (HAVS), carpet 
layer's knee, and herniated spinal disc. Injuries arising from 
slips, trips, falls, motor vehicle accidents, or similar accidents 
are not MSDs.

    The definition of ``musculoskeletal disorder (MSD)'' in the final 
rule differs somewhat from the proposed definition. The final rule 
limits the definition to those MSDs involving certain body parts: the 
neck, shoulder, elbow, forearm, wrist, hand, abdomen (hernia only), 
back, knee, ankle and foot. This definition, and the purpose paragraph 
(paragraph (a)) both also make clear that this standard does not cover 
injuries caused by slips, trips, falls, motor vehicle accidents, or 
other similar accidents (e.g., being caught in moving parts). OSHA has 
made these changes in response to criticisms that the proposed 
definition was too broad (see, e.g., Ex. 30-1216, 30-2035, 30-3866, 30-
4821, 32-208-1, 32-368-1, 30-3937, 500-1-116, Tr. 15310).
    Some commenters raised issues about the MSDs covered by the 
standard and their relationship to psychosocial effects and non-
occupational factors (see, e.g., Exs. 500-1-1116, 30-3211, 30-3866). 
These comments and issues are discussed in the Health Effects section 
of the preamble, Section V, rather than in this definitions section.
    Other commenters objected because the acronyms MSD and MSDs are 
similar to MSDS, which stands for the Material Safety Data Sheets 
required by OSHA's hazard communication standard, 29 CFR 1910.1200 
(see, e.g.,

[[<strong>Page</strong> 68432]]

Exs. 30-2041 and 30-0522). However, because ``musculoskeletal 
disorder'' is the scientifically correct term for these conditions and 
MSD is the widely known abbreviation for the term, OSHA continues to 
use both ``musculoskeletal disorders'' and its acronym in the final 
rule.
    Some commenters urged OSHA to add other examples such as thoracic 
outlet syndrome to the list of examples accompanying the definition 
(see, e.g., Exs. 30-2825 and 30-3332). The list of MSDs included in the 
final rule is only a list of examples; OSHA recognizes that there are 
many other MSDs, such as thoracic outlet syndrome, that could be 
included in this list.
    There was some comment that OSHA should adopt a definition of MSDs 
developed by other organizations such as NIOSH (see, e.g., Exs. 30-3211 
and 30-3765). For example, the Dow Chemical Company (Ex. 30-3765) 
recommended that OSHA adopt the NIOSH definition of MSD and the Society 
for Human Resource Management (Exs. OR-364, Tr. 15310-15311) suggested 
that OSHA rely on a medical definition of MSD, such as one taken 
directly from Merck's Manual. 
    OSHA's definition of MSD is, in fact, very similar to NIOSH's 
definition, as reflected in the Institute's publication, Elements of 
Ergonomics Programs (DHHS, Publication No. 97-117), particularly with 
respect to the soft tissues included and the exclusion of accidental 
injuries.
    MSD hazard means the presence of risk factors in the workplace that 
occur at a level of magnitude, duration, or frequency that is 
reasonably likely to cause MSDs that result in work restrictions or 
medical treatment beyond first aid. The definition of ``MSD hazard'' in 
the final rule differs from the definition in the proposed rule; it has 
been revised for clarity, as requested by some commenters (see, e.g., 
Ex. 30-2986). Other commenters found the proposed definition of MSD 
hazards circular (see, e.g., Exs. 30-3344 and 30-4674). The revised 
definition addresses this concern, because it focuses on the magnitude, 
frequency, and duration of identified risk factors and their 
relationship to MSD hazards.
    MSD incident means an MSD that is work related, requires time away 
from work, restricted work, or medical treatment beyond first aid, or 
involves MSD signs or MSD symptoms that last 7 or more consecutive 
days. (See the discussion of the terms MSD signs and MSD symptoms 
below.) The definition of MSD incident is new to the final rule. See 
the summary and explanation section describing the provisions of 
paragraph (e), in which the term ``MSD incident'' is used in 
association with the standard's action trigger.
    MSD signs are objective physical findings that an employee may be 
developing an MSD. Examples of MSD signs are: decreased range of 
motion; deformity; decreased grip strength; and loss of muscle 
function. The final rule's definition is essentially the same as the 
proposed definition, except for minor editorial revisions made for 
clarity. Additional discussion of this term appears in the summary and 
explanation for paragraph (d) regarding the reporting of MSD incidents, 
paragraph (e), the action trigger, and the Health Effects section of 
the preamble (Section V).
    Most of the comments OSHA received on the list of examples of MSD 
signs included in the proposal concerned the role of the health care 
professional (HCP) and the phrase ``objective physical findings'' (see, 
e.g., Exs. 30-3818, 30-3826, 30-3934, 30-2993, 30-3167, 30-3745, 30-
4814 and 30-434). These commenters argued that the rule should be 
structured so that only an HCP, not the employer, can determine whether 
a given MSD is associated with objective physical findings. The 
Newspaper Association of America objected to the list of signs because 
``[O]SHA has inexplicably chosen to provide only four examples of MSD 
signs and leaves employers to guess at what may constitute objective 
physical findings'' (Ex. 30-2986). In response, OSHA notes that 
employers are always free to involve an HCP in their determinations. 
However, OSHA does not believe that employers will generally have 
difficulty deciding whether an MSD sign is related to an employee 
report because, by definition, signs are visible indications observable 
both by the employee and the employer.
    MSD symptoms are defined in the final rule as physical indications 
that an employee may be developing an MSD. Examples of MSD symptoms 
are: pain, numbness, tingling, burning, cramping, and stiffness. The 
final rule's list of examples is essentially the same as the list in 
the proposal, except that it is more clearly written. Most of the 
comments relating to this term have already been discussed above under 
``musculoskeletal disorder.'' Additional discussion of this term 
appears in the summary and explanation for paragraph (e) on the 
reporting of MSD incidents.
    Personal protective equipment (PPE) is the equipment employees wear 
that provides a protective barrier between the employee and an MSD 
hazard. Examples of PPE are vibration-reduction gloves and carpet 
layer's knee pads. The final rule's definition is essentially identical 
to the definition proposed, except that the word ``effective'' before 
``protective barrier'' has been deleted because the effectiveness of 
PPE depends on the circumstances in a particular workplace and is 
therefore not appropriate for a definition. One commenter noted that 
the definition of PPE was clear. Additional discussion relating to the 
meaning of this term can be found in the summary and explanation of 
paragraph (l).
    Problem job means a job that the employer has determined poses an 
MSD hazard to employees in that job. The definition of the term 
``problem job'' has been changed from the definition in the proposal, 
which defined a problem job as ``* * * a job in which a covered MSD is 
reported. A problem job also includes any job in the workplace that 
involves the same physical work activities and conditions as the one in 
which the covered MSD is reported, even if the jobs have different 
titles or classifications.'' (See the definition of the term ``job'' 
above.)
    Commenters were concerned that the definition unnecessarily 
expanded the scope of the standard (see, e.g., Exs. 32-206-1, 32-368-1, 
30-294, 30-2208-1, 30-3284 and 31-336), or requested clarification of 
ways an employer could use to determine when physical work activities 
and conditions were the ``same'' (see, e.g., Ex. 30-3765).
    In response, OSHA notes that the Agency intends the ``same job'' 
requirements to extend the protections provided by the standard to 
employees who are fortunate enough not to have experienced an MSD 
incident but who are in ``higher-risk'' jobs, as demonstrated by the 
fact that one employee in the job has already experienced an incident 
and the job has been determined to meet the action trigger. The 
standard's ``same job'' requirements are preventive in nature and will 
benefit workers in the job as well as saving the employer the costs 
associated with the MSDs that are averted by fixing the jobs of other 
employees in the same job. As to the concern about how an employer can 
know which jobs are the same, OSHA believes that the Basic Screening 
Tool will be useful in cases where deciding which jobs are the same is 
difficult.
    Risk factor, as used in this standard, means force, awkward 
posture, repetition, vibration, and contact stress. The term replaces 
the term ``ergonomic risk factors,'' which was defined in the proposed 
rule. There was considerable comment in response to the definition of 
``ergonomic risk factors'' in the proposed rule. Commenters stated that

[[<strong>Page</strong> 68433]]

the term was vague and too broad (see, e.g., Exs. 30-1011 and 30-2986) 
and did not provide employers with enough information to allow them to 
determine if the factors are present in particular jobs and, if so, the 
duration of exposure to them (see, e.g., Ex. 30-2986). A large number 
of commenters expressed concern that they would be unable to quantify 
the risk factors in a job based on the amount of information provided 
in the proposal (see, e.g., Exs. 30-1722, 30-3032, 30-3336, 30-3765, 
30-3813 and 30-3866).
    The concerns raised by commenters have largely been addressed by 
the final rule, which limits the number of risk factors covered by the 
standard to those most often associated with MSDs and additionally 
provides clear definitions for each risk factor of the magnitude, 
frequency, or duration at which exposure poses a potential risk (the 
Basic Screen levels) and the level deemed to pose an MSD hazard (e.g., 
the levels indicated by the hazard identification tools in Appendices 
D-1 and D-2).
    Some commenters raised legal issues, i.e., the alleged vagueness of 
the term ``risk factors'' and the lack of precise quantitative 
estimates of the levels at which each risk factor poses risk (see, 
e.g., Exs. 32-368-1 and 32-206-1), and the perceived need to establish 
quantitative permissible exposure limits for the risk factors (see, 
e.g., Ex. 30-3784). These issues are discussed at length in the Other 
Stautory Issues and Legal Authority sections of this preamble.
    Work practices are changes in the way an employee performs the 
physical work activities of a job that reduce exposure to MSD hazards. 
Work practice controls involve procedures and methods for safe work. 
Examples of work practice controls for MSD hazards include:

(a) Using neutral work postures;
(b) Using lifting teams;
(c) Taking micro-breaks; and
(d) Avoiding lifts involving extended reaches or twisted torso.
(e) Conditioning or work-hardening programs.

    The proposed rule defined work practices in essentially the same 
way, except that OSHA has added a conditioning or work-hardening 
program to the rule in response to comments in the record (see, e.g., 
Exs. 30-1902, 30-3686, 32-22, and 32-210, and 30-4137, Tr. 8720, Tr. 
12472-12479). These commenters stated that they use these program to 
protect newly assigned workers during the period when they are first 
exposed to risk factors on the job. OSHA notes in the definition for 
``work restrictions'' that conditioning and work-hardening programs are 
not to be considered work restrictions for the purposes of this 
standard.
    In the Issues section of the proposal, OSHA asked for comment about 
the appropriate work practices or controls employers could use to 
prevent Computer Vision Syndrome (CVS). In response to this inquiry, 
OSHA received several comments (see, e.g., Exs. 30-3032, 30-2387, 30-
2208). One commenter stated that controlling glare, providing adequate 
lighting, well-designed software, and regularly shifting the static 
fixed focal point of the eye are all approaches that have been used to 
address CVS. Other commenters (see, e.g., Exs. 30-3032, 30-2208) urged 
OSHA not to include CVS in the list of examples of MSDs in the final 
rule. OSHA agrees that not enough is currently known about CVS and its 
causes for the final rule to focus on it.
    Work related means that an exposure in the workplace ``caused or 
contributed'' to an MSD or ``significantly aggravated'' a pre-existing 
MSD. ``Work-related'' was not defined in the proposal. The final rule 
uses the term ``work related'' in the definition of an MSD incident. In 
the proposed rule, OSHA used the term ``work relatedness'' in the 
definitions of ``covered MSD'' and ``OSHA recordable MSD.''
    A number of commenters objected to the term ``work-related'' in the 
context of OSHA recordable injuries and illnesses because they believe 
the term is so broad that it often includes non-work related MSDs (see, 
e.g., Exs. 500-188, 30-2489, 31-336, 30-2834, 30-2986, 30-1722 and 30-
1037). For example, the Center for Office Technology argued that the 
proposal was designed in a way that would permit a program to be 
triggered by an episode of weekend overexertion that interfered with 
work on Monday (Ex. 30-2208-2), and the International Council of 
Shopping Centers (Ex. 30-2489) expressed the same concern. These 
commenters are essentially objecting to OSHA's definition of a 
recordable injury under Part 1904, the Agency's recordkeeping rule; 
that rule defines a work-related injury as one caused, contributed to, 
or aggravated by an event or exposure in the workplace, without regard 
to the extent of the contribution of work to the injury.
    Several participants urged OSHA not to include the concept of work 
aggravation of a pre-existing MSD in the final rule (see, e.g., Exs. 
30-629, 30-1037, 30-3159, 30-4185 and 31-336). Typical of those 
comments was one by Uniservice, Inc. (Ex. 30-2834), which stated, 
``[w]e will have to make changes to fix a job for a supposed MSD that 
was not caused by workplace exposure in the first place [if OSHA 
includes the significant aggravation definition in the standard].'' 
Other commenters focused their concern about including aggravation in 
the concept of work-relatedness on back injuries because back pain is 
so common both inside and outside the workplace (see, e.g., Exs. 30-
3784, 30-4185, 31-336 and 30-3937). The final rule does not rely on an 
OSHA recordable injury or illness when defining an MSD incident; the 
final rule's definition specifies what kinds of MSDs are included 
(those involving restricted work, for example). OSHA believes that the 
increased clarity of the final rule will alleviate many of these 
commenters' concerns.
    Work restriction protection (WRP) means the maintenance of the 
earnings and other employment rights and benefits of employees who are 
on temporary work restrictions. Benefits include seniority, insurance 
programs, retirement benefits, and savings plans. In the proposal, OSHA 
defined ``work restriction protection'' to mean:

the maintenance of the earnings and other employment rights and 
benefits of employees who are on temporary work restriction. For 
employees who are on restricted work activity, WRP includes 
maintaining 100% of the after-tax earnings employees with covered 
MSDs were receiving at the time they were placed on restricted work 
activity. For employees who have been removed from the workplace, 
WRP includes maintaining 90% of the after-tax earnings. Benefits 
mean 100% of the non-wage-and-salary value employees were receiving 
at the time they were placed on restricted work activity or were 
removed from the workplace. Benefits include seniority, insurance 
programs, retirement benefits and savings plans.

    The language beginning with ``For employees'' and ending with 
``from the workplace'' (outlined in the above quote) has been removed 
from the final rule's definition. Additional discussion relating to 
both the meaning of this term and the regulatory requirements on work 
restriction protection can be found in the summary and explanation of 
paragraph (r).
    Work restrictions are defined as limitations, during the recovery 
period, on an employee's exposure to MSD hazards. Work restrictions may 
involve limitations on the work activities of the employee's current 
job (light duty), transfer to temporary alternative duty jobs, or time 
away from the workplace to recuperate. For the purposes of this 
standard, temporarily reducing an employee's work requirements in a new 
job in order to reduce muscle soreness

[[<strong>Page</strong> 68434]]

resulting from the use of muscles in an unfamiliar way is not a work 
restriction. Further, the day an employee first reports an MSD is not 
considered a day of work restriction, even if the employee is removed 
from his or her regular duties for part of the day.
    This definition is a revision of the proposed definition. The 
proposed definition of work restriction included the sentence: ``To be 
effective, work restrictions must not expose the injured employee to 
the same MSD hazards as were present in the job giving rise to the 
covered MSD.'' This sentence has been removed from the definition 
because it is better suited to the summary and explanation for 
paragraph (r). See the discussion of the comments received on Work 
Restriction Protection in general above and in the summary and 
explanation for paragraph (r).
    You means the employer, as defined by the Occupational Safety and 
Health Act of 1970 (29 U.S.C. 651 et seq.). The final rule's definition 
is identical to the proposed definition (64 FR 66078). There were no 
comments on this definition.
    Several terms that were defined in the proposal are not used in the 
final rule. They include ``manual handling jobs,'' ``manufacturing 
jobs,'' and ``have knowledge.'' ``MSD management'' was also defined 
separately in the proposal but is now discussed in the regulatory text 
and summary and explanation for paragraph (p).
    Some commenters suggested that OSHA define new terms, including the 
term ``employee.'' The Alliance of American Insurers (AAI) (Ex. 30-
3751) objected to the proposal's cross-reference to the definition of 
employee contained in the OSH Act. The Alliance asked OSHA to provide 
additional clarification about who is or is not an employee under 
various types of employer/employee relationships, such as employee 
leasing arrangements. The AAI said: ``how is OSHA to make WRP 
determinations? What if one entity is held to be responsible for WRP 
but the other entity is responsible for workers' compensation 
benefits?'' This issue is discussed in detail in the summary and 
explanation for paragraph (r).
    The DuPont SHE Excellence Center (Ex. 30-2134) recommended the 
addition of a definition for workplace, commenting that in the proposed 
rule:

    ``There is no definition of workplace incorporated in this 
section [proposed definition of problem job], which creates more 
confusion. Is the workplace the specific building the job is 
located, the same physical site (which might contain several 
buildings), or the entire company with all of its locations within 
the U.S. and its territories? Some jobs take place out-of-doors, in 
varied locations which can move from place to place. How are these 
jobs considered under the ``problem job'' definition?''

    The final rule makes clear that the physical establishment that 
houses the problem job, or to which the injured employee and other 
employees in the same job report, limits the program activities 
required by the standard. The standard does not impose corporate-wide 
obligations on businesses that have multiple establishments. Instead, 
the standard is job-based in the first instance, i.e., employers are 
only required to implement the ergonomics program in those jobs 
identified as problem jobs. It is establishment-based in the second 
instance, i.e., employers are only required to include in their program 
the problem job (and the workers in them) within the establishment to 
which the problem job is ``attached.'' This means that, where the 
workforce is mobile, the establishment to which the injured employee 
reports would be considered the establishment, for the purposes of the 
standard. Since the standard requires employers to extend the 
standard's protections to all employees in the same job, the employer 
is required to ``fix'' the MSD hazards in the workstations or work 
environments of all employees in the same job who are located in, or 
report to, the same establishment.
    For the purposes of the standard, OSHA defines an establishment as 
a single physical location where business is conducted or where 
services or industrial operations are performed. For activities where 
employees do not work at a single physical location, such as 
construction; transportation; communications, electric, gas and 
sanitary services; and similar operations, the establishment is 
represented by main or branch offices, terminals, stations, etc., that 
either supervise such activities or are the base from which personnel 
carry out these activities.
    One commenter (Exs. 30-2825 and 30-3332) suggested that OSHA add a 
definition of repetitive motion jobs to the final rule. OSHA does not 
believe such a definition is necessary because the final rule contains 
clear definitions of each of the risk factors (see the Basic Screening 
Tool in Table 1).
    Several commenters asked OSHA to clarify the definitions of 
industries covered and exempted from the final rule (see, e.g., Exs. 
30-1897, 30-3818 and 30-4716). For example, the Honorable James Talent, 
Chairman of the U.S. House of Representatives Committee on Small 
Business (Ex. 30-1897), noted that the proposed rule did not apply to 
agriculture, construction, or maritime operations, but did not clarify 
each of these terms. Paragraph (b) of the final rule provides clear 
definitions of the standard's scope and explicitly states that it does 
not apply to maritime, agricultural, railroad, or construction 
employment.
    Finally, some commenters suggested that OSHA define the term 
recovery period, which was used in the definition of work restriction 
protection (WRP) (see, e.g., Exs. 30-3749 and 30-3344). OSHA has not 
done so because this term is used in the final rule in its everyday 
sense, and is therefore clear on its face.

V. Health Effects

    In this section, OSHA presents the evidence contained in the 
rulemaking record that addresses the causal relationship between 
exposure to biomechanical risk factors at work and an increased risk of 
developing musculoskeletal disorders (MSDs). This evidence consists of 
epidemiological studies of exposed workers in diverse occupational 
settings, biomechanical studies describing the relationships between 
exposure to risk factors and associated forces imposed on 
musculoskeletal tissue, studies of tissue pathology describing the 
kinds of tissue alterations that have been seen to result from such 
forces, and medical and diagnostic information relating to MSDs. In 
making its findings from this evidence, OSHA is relying in part on the 
extensive scientific evidence presented in the detailed Health Effects 
Appendices to the proposal (64 FR 65865-65926) (Ex. 27-1), located on 
OSHA's webpage at <A HREF="http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.osha.gov">http://www.osha.gov</A> and summarized in this section. 
In addition, OSHA's analysis includes results from several other 
studies placed into the rulemaking record after publication of the 
proposed rule, as well as comment and testimony from many distinguished 
scientific experts.
    This section is divided into the following seven parts:

    <bullet> Part A, Description of Biomechanical Risk Factors;
    <bullet> Part B, Overview of the Health Effects Evidence;
    <bullet> Part C, Evidence on Neck and Shoulder Disorders;
    <bullet> Part D, Evidence on Upper Extremity Disorders;
    <bullet> Part E, Evidence on Back Disorders;
    <bullet> Part F, Evidence on Lower Extremity Disorders; and
    <bullet> Part G, OSHA's Response to Issues Raised in the 
Rulemaking.

[[<strong>Page</strong> 68435]]

A. Biomechanical Risk Factors

    Biomechanical risk factors are the aspects of a job or task that 
impose a physical stress on tissues of the musculoskeletal system, such 
as muscles, nerves, tendons, ligaments, joints, cartilage, spinal 
discs, or (in the case of hand-arm vibration syndrome) blood vessels of 
the upper extremities. To accomplish motion and work, muscle, nerves, 
connective tissue, and skeleton are affected by a number of external 
and internal physical demands causing metabolic and compensatory tissue 
reactions. External demands can include direct pressure on tissues or 
tissue friction. Internal responses can include inflammatory responses 
to tissue injury, neurochemical changes, and altered metabolism. The 
consequences of these external and internal demands associated with 
work activities can include a spectrum of symptoms or clinical 
findings. Although some types of tissue, like skeletal muscle, have the 
ability to recover after an injury that does not physically disrupt the 
tissue, exceeding tissue limits may result in permanent damage to a 
tissue. However, skeletal muscle is just one type of tissue that can be 
affected; other tissues like tendon, ligament, nerve, and cartilage can 
also be damaged by exposure to excessive physical task factors. These 
tissues, unlike skeletal muscle, do not have the same capacity for 
recover and repair after injury. (Each part of this Health Effects 
section briefly summarizes the pathogenesis of MSDs; OSHA's Health 
Effects Appendices (Ex. 27-1), developed for the proposed rule, 
contains detailed discussions of the scientific literature describing 
the pathogenesis of MSDs).
    The biomechanical risk factors addressed by this final rule are 
repetition, force, awkward postures, vibration to the upper extremity 
(i.e., segmental vibration), and contact stress. In occupations where 
an increased prevalence or incidence of MSDs has been observed, these 
risk factors frequently occur in combination; the level of risk 
associated with exposure depends on the intensity and duration of 
exposure as well as the amount of recovery time available to the 
strained tissues for repair. Soft tissues of the musculoskeletal system 
will develop tolerance to physical loading if sufficient recovery time 
is provided. Without adequate recovery time, affected tissues can 
accumulate damage or become more prone to failure. The need for 
adequate recovery time between exposure events means that the pattern 
of exposure also has an important influence on risk. The biomechanical 
risk factors covered in the final rule are force, repetition, awkward 
postures, contact stress, and segmental vibration; the basic screening 
tool in the final rule describes criteria for each of these risk 
factors that identifies those jobs where there is a potential risk of 
MSDs. Each of these risk factors is described below.

Force

    Force refers to the amount of physical effort that is required to 
accomplish a task or motion. Force also refers to the degree of loading 
to muscles and other tissues as a result of applying force to perform 
work. Tasks or motions that require application of higher force place 
higher mechanical loads on muscles, tendons, ligaments, and joints (Ex. 
26-2). The force required to complete a movement increases when other 
risk factors are also involved. For example, more physical effort may 
be needed to perform tasks when the speed or acceleration of motions 
increases, when vibration is present, or when the task also requires 
awkward postures. Hand tools that require use of pinch grips require 
more forceful exertions to manipulate the tool than do those that 
permit use of power grips.
    Relationships among external loads, internal tissue loads, and 
mechanical and physiological responses have also been studied 
extensively, using simulation, direct instrumentation, indirect 
instrumentation, and epidemiological studies. In a report on the 
Research Base of Work-Related Musculoskeletal Disorders prepared by the 
National Research Council (NRC) in response to a request from the 
National Institutes of Health (NIH) (Ex. 26-37), the steering committee 
provides some rationale for evaluating and controlling biomechanical 
risk factors, specifically force:

    <bullet> The concept of force can be generalized to encompass 
numerous ways of measuring and characterizing external loads. For 
example, force can be measured in terms of the weight of parts, tool 
reaction force, perceived exertion, muscle electrical activity, or 
observer ratings.
    <bullet> Internal loads can be estimated by using external 
loads. For example, a worker must bend or stoop to lift something 
from the floor; a worker will exert more force on a stiff keyboard 
than a light touch keyboard. Understanding these relationships 
allows prediction of internal loads.
    <bullet> Predicted internal loads generally agree with measured 
internal and external loads. For example, measurements of muscle 
loads during activity using electromyography generally agree with 
predicted values.

    Force can be assessed qualitatively or quantitatively. Quantitative 
measures include strain gauges, spring scales, and electromyography to 
measure muscle activity. A qualitative assessment of force is based on 
direct observation of the amount of physical exertion required to 
complete a task, and is usually graded on an ordinal scale (i.e., low, 
medium, high).

Repetition

    Repetition refers to the frequency with which a task or series of 
motions are repeated with little variation in movement. Although force 
and/or awkward postures can combine with repetition to increase the 
risk of MSDs over that of repetition alone, acceleration and velocity 
of repetitive movement are also important considerations in that they 
may ``cause damage that would not be predicted by muscle forces or 
joint angles alone'' (Washington State CES, p.20, Ex. 500-71-93).
    Repetitive motions occur frequently in manufacturing operations 
where production and assembly processes have been broken down into 
small sequential steps, each performed by different workers. However, 
it also applies to many manual handling operations, such as warehouse 
operations and baggage handling. Repetition is typically assessed by 
direct observation or videotaping of job tasks. The intensity of 
exposure is usually expressed as a frequency of motion or as a percent 
of task cycle time, where a cycle is a pattern of motions.

Awkward Postures

    Awkward postures refer to positions of the body (e.g., limbs, 
joints, back) that deviate significantly from the neutral position 
while job tasks are being performed. For example, when a person's arm 
is hanging straight down (i.e., perpendicular to the ground) with the 
elbow close to the body, the shoulder is said to be in a neutral 
position. However, when employees are performing overhead work (e.g., 
installing or repairing equipment, grasping objects from a high shelf) 
their shoulders are far from the neutral position. Other examples 
include wrists bent while typing, bending over to grasp or lift an 
object, twisting the back and torso while moving heavy objects, and 
squatting. Awkward postures often are significant contributors to MSDs 
because they increase the exertion and the muscle force that is 
required to accomplish the task, and compress soft tissues like nerves, 
tendons, and blood vessels. As used in the final rule's basic screening 
tool, awkward postures may be either static postures held for

[[<strong>Page</strong> 68436]]

prolonged periods of time, or they may occur repetitively.
    Awkward posture is the primary ergonomic risk factor to which 
employees are exposed when the height of working surfaces is not 
correct. Working at surfaces that are too high can affect several parts 
of the body. Employees may have to lift and/or move their shoulders, 
elbows and arms (including hands and wrists) into uncomfortable 
positions to perform the job tasks on higher surfaces. For example, 
employees may have to raise their shoulders or move their elbows out 
from the side of their body to do a task on a high working surface. 
Also, they may have to bend their heads and necks to see the work they 
are doing.
    Working surfaces that are too high usually affect the shoulders. 
The muscles must apply considerably more contraction force to raise and 
hold the shoulders and elbows out to the side, particularly if that 
position also must be maintained for more than a couple of seconds. The 
shoulder muscles fatigue quickly in this position.
    On the other hand, when surfaces are too low, employees may have to 
bend their backs and necks to perform their tasks while hunched over 
the working surface. They may also have to reach down with their arms 
and backs to do the tasks. Where working surfaces are very low, 
employees may have to kneel or squat, which places very high forces on 
the knees to maintain the position and the weight of the body. Working 
surfaces that are too low usually affect the lower back and 
occasionally the neck.
    Working in awkward postures increases the amount of force needed to 
accomplish an exertion. Awkward postures create conditions where the 
transfer of power from the muscles to the skeletal system is 
inefficient. To overcome muscle inefficiency, employees must apply more 
force both to initiate and complete the motion or exertion. In general, 
the more extreme the postures (i.e., the greater the postures deviate 
from neutral positions), the more inefficiently the muscles operate 
and, in turn, the more force is needed to complete the task. Thus, 
awkward postures make forceful exertions even more forceful, from the 
standpoint of the muscle, and increase the amount of recovery time that 
is needed.
    Awkward postures are assessed in the workplace by observing joint 
angles during the performance of job tasks. Observed postures can be 
compared qualitatively to diagrams of awkward postures, such as is done 
in many job analysis tools, or angles can be measured quantitatively 
from videotape recordings.

Contact Stress

    As used in many ergonomics texts and job analysis tools, contact 
stress results from activities involving either repeated or continuous 
contact between sensitive body tissue and a hard or sharp object. The 
basic screening tool in the final rule includes a particular type of 
contact stress, which is using the hand or knee as a hammer (e.g., 
operating a punch press or using the knee to stretch carpet during 
installation). Thus, although contact stress is covered in the final 
rule as a single risk factor, it is really a combination of force and 
repetition. Mechanical friction (i.e., pressure of a hard object on 
soft tissues and tendons) causes contact stress, which is increased 
when tasks require forceful exertion. The addition of force adds to the 
friction created by the repeated or continuous contact between the soft 
tissues and a hard object. It also adds to the irritation of tissues 
and/or to the pressures on parts of the body, which can further inhibit 
blood flow and nerve conduction.
    Contact stress commonly affects the soft tissue on the fingers, 
palms, forearms, thighs, shins and feet. This contact may create 
pressure over a small area of the body (e.g., wrist, forearm) that can 
inhibit blood flow, tendon and muscle movement and nerve function. The 
intensity of exposure to contact stress is usually determined 
qualitatively through discussion with the employee and observation of 
the job.

Segmental Vibration

    Vibration refers to the oscillatory motion of a physical body. 
Segmental, or localized vibration, such as vibration of the hand and 
arm, occurs when a specific part of the body comes into contact with 
vibrating objects such as powered hand tools (e.g., chain saw, electric 
drill, chipping hammer) or equipment (e.g., wood planer, punch press, 
packaging machine).
    Although using powered hand tools (e.g., electric, hydraulic, 
pneumatic) may help to reduce risk factors such as force and repetition 
over using manual methods, they can expose employees to vibration. 
Vibrating hand tools transmit vibrations to the operator and, depending 
on the level of the vibration and duration of exposure, may contribute 
to the occurrence of hand-arm vibration syndrome or Raynaud's 
phenomenon (i.e. vibration-induced white-finger MSDs) (Ex. 26-2).
    The level of vibration can be the result of bad design, poor 
maintenance, and age of the powered hand tool. For example, even new 
powered hand tools can expose employees to excessive vibration if it 
they do not include any devices to dampen the vibration or in other 
ways shield the operator from it. Using vibrating hand tools can also 
contribute to muscle-tendon contractile forces owing to operators 
having to use increased grip force to steady tools having high 
vibration.
    Vibration from power tools is not easy to measure directly without 
the use of sophisticated measuring equipment. However, vibration 
frequency ratings are available for many recently designed hand tools.
    Based on the whole of the scientific literature available at the 
time of the proposal, OSHA also identified prolonged sitting and 
standing (a form of static posture) and whole-body vibration as risk 
factors for MSDs; in addition, OSHA identified cold temperatures as a 
risk factor modifier because it could require workers to increase the 
force necessary to perform their jobs (such as having to grip a tool 
more tightly) (64 FR 65865-65926) (Ex. 27-1). The final rule does not 
explicitly include these risk factors. For prolonged standing and 
sitting, and for cold temperatures, although there is evidence of an 
increased risk of MSDs with exposure (e.g., see Skov, Ex. 26-674), the 
available evidence did not permit the Agency to provide sufficient 
guidance to employers and employees on the levels of exposure that 
warrant attention. For whole-body vibration, there was substantial 
evidence of a causal association with low back disorders (e.g., see 
NIOSH 1997); however, heavy equipment and trucks, the most common 
sources of whole-body vibration, are seldom rated for vibration 
frequencies and intensities. In addition, measurement of whole-body 
vibration levels requires special equipment and training that would be 
difficult for most employers to obtain. Therefore, OSHA determined that 
it was appropriate not to include whole-body vibration in the final 
rule at this time.
    For the biomechanical risk factors of force, repetition, awkward 
postures, segmental vibration, and contact stress, OSHA has concluded 
that strong evidence exists for a positive relationship between 
exposure to these risk factors and an increased risk of developing 
MSDs, based on the scientific evidence and testimony described in this 
section of the final rule's preamble. The risk factors identified by 
the Agency as being causally related to the development of MSDs and 
that are covered in the final rule are the same risk factors that have

[[<strong>Page</strong> 68437]]

been addressed by other reputable scientific and regulatory bodies, 
both nationally and internationally, who face the challenge of either 
reducing the incidence of MSDs or contributing to the scientific basis 
for these actions. The two most current and thorough reviews on this 
topic are NIOSH's Critical Review of Epidemiologic Evidence for Work-
Related Musculoskeletal Disorders of the Neck, Upper Extremity, and Low 
Back (Bernard, 1997; Ex. 26-1) and the National Research Council/
National Academy of Science's Work-Related Musculoskeletal Disorders: 
Report, Workshop Summary, and Workshop Papers (1999; Ex. 26-37). 
NIOSH's review focused on repetition, force, posture, and vibration 
when evaluating epidemiologic evidence for the neck, shoulder, elbow, 
and hand/wrist. For the low-back, the authors looked at the evidence 
for heavy physical work, lifting and forceful movements, bending and 
twisting (awkward postures), whole body vibration and static work 
postures. The ``work factors'' identified by the NRC in their report on 
Work-Related Musculoskeletal Disorders are the same as the 
``biomechanical risk factors'' identified by OSHA. Although terms may 
differ depending upon the part of the body being described, it is easy 
to see the relationship between heavy physical work and lifting and the 
concept of force/exertion to the back, for example .
    The Steering Committee Report for the NRC workshop on ``Examining 
the Research Base (for Work-Related MSDs)'', participants agreed there 
is

``enough scientific evidence to confirm that strain on 
musculoskeletal tissue increases when humans perform activities that 
involve forceful manual exertions, awkward postures, repetitive or 
prolonged exertions, exposure to vibrations and exposure to cold 
temperatures.''

    However, in a separate paper prepared for the NRC/NAS workshop, 
Radwin and Lavender also discuss ``workplace layout,'' ``interactions 
with objects,'work scheduling'' and other ``workplace design factors,'' 
as factors that these authors, as well as others, have studied in 
relation to MSDs. Although there is strong agreement on biomechanical 
factors associated with MSDs, the science is still evolving with regard 
to other types of factors. Thus, when sources refer to biomechanical 
risk factors, all literature reviewed from the rulemaking record 
identified the same basic risk factors, all essentially related to 
force/exertion, repetition, posture and vibration.
    Literature reviews published in the scientific literature also 
evaluate these same risk factors. Literature reviews of this type use 
selection criteria to capture the best-designed studies with a 
particular focus, usually risk factors associated with a specific type 
of disorder, for analysis. Burdorf and Sorock reviewed 35 articles that 
evaluated risk factors for back disorders and concluded that lifting or 
carrying loads (force), whole-body vibration and frequent bending and 
twisting (awkward postures) were consistently related to work-related 
low-back disorders (1997; Ex. 500-71-24). In a systematic review of 31 
studies, Hoogendoorn et al (1997; Ex. 500-71-32) found strong evidence 
exists for manual materials handling, bending and twisting (awkward 
posture), and whole-body vibration as risk factors for back pain, and 
moderate evidence exists for patient handling and physical work.
    In their review of the literature on the role of physical load 
factors in carpal tunnel syndrome, Viikari-Juntura and Silverstein 
found an association with carpal tunnel syndrome and forceful, 
repetitive work, extreme wrist postures and vibration (1999; Ex. 32-
339-1-56). Other authors (Ariens et al., 2000; Ex. 500-71-23) found a 
relationship between neck pain and neck flexion, arm force, arm 
posture, duration of sitting, twisting or bending of the trunk, hand-
arm vibration, and workplace design.
    In both written submissions to the record, and in oral testimony, 
numerous scientific experts confirmed and substantiated OSHA's position 
that sufficient scientific evidence exists, and is contained in the 
record, to conclude that workplace exposure to the biomechanical risk 
factors described above increase the risk for work-related MSDs (Exs. 
37-1; 37-2; 37-3; 37-6; 37-8; 38-9; 37-10; 37-13; 37-15; 37-16; 37-17; 
37-18; 37-21; 37-27; 37-28; 26-37). Scientists who testified at the 
hearings also confirmed that each of these risk factors are linked to 
an increased risk of developing an MSD in exposed workers (Dr. Don 
Chaffin, University of Michigan, Tr 8254; Dr. Nicholas Warren, 
University of Connecticut Health Center, Tr.1084-85; Dr. Martin 
Cherniak, Ergonomics Technology Center of Connecticut, Tr. 1128; Dr. 
Richard Wells, University of Waterloo, Tr. 1353-54; Dr. Robert 
Harrison, Tr. 1648; Dr. Amadio, Mayo Clinic, Tr. 9815, 98; Dr. Eckardt 
Johanning, Eastern New York Occupational and Environmental Health 
Center, Tr. 16831-33; Dr. Jim McGlothlin, Purdue University, Dr. 
Malcolm Pope, Tr. 16808; Dr. Margit Bleeker, Tr. 16826). This written 
and oral testimony from scientific experts provides a compelling case 
establishing the link between exposure to biomechanical risk factors 
and an increased risk of MSD incidence.
    OSHA heard from a number of scientists and physicians during it's 
hearing with comments along the lines of that by Dr. Robert Harrison, 
from the University of California (Tr. 1649-50):

    The jobs and tasks my patients are performing are the ones the 
literature has identified as high-risk jobs with exposure to many of 
the same physical risk factors. In fact, my patients are exposed to 
the identical physical work activities and conditions that have been 
identified by OSHA as causing excessive exposure to force, frequent 
repetition, awkward posture, contact stress, vibration and cold 
temperatures.

    The record contains many US and international regulations and 
guidelines that reflect the same biomechanical risk factors addressed 
in the final rule; some are listed below:
    <bullet> National Research Council. (1999) Work-Related 
Musculoskeletal Disorders: Report, Workshop Summary, and Workshop 
Papers. National Academy Press. (Ex. 26-37);
    <bullet> National Institute for Occupational Safety and Health. 
(1997) Musculoskeletal Disorders and Workplace Factors. Centers for 
Disease Control and Prevention (Ex. 26-1);
    <bullet> National Institute for Occupational Safety and Health. 
(1998) Elements of Ergonomics Programs, A Primer Based on Workplace 
Evaluations of Musculoskeletal Disorders. (Ex. 26-2);
    <bullet> European Agency for Safety and Health at Work. Work-
related neck and upper limb musculoskeletal disorders (1999). (Ex.500-
71-28);
    <bullet> Department of Labor and Industries, Washington State. (5/
25/00) Concise Explanatory Statement, WAC 296-62-051, Ergonomics (Ex. 
500-71-93);
    <bullet> Ergonomics for the Prevention of Musculoskeletal 
Disorders, Swedish National Board of Occupational Safety and Health on 
Ergonomics for the Prevention of Musculoskeletal Disorders. AFS 1998:1; 
(Ex. 500-71-14);
    <bullet> National Codes of Practice for the Prevention of 
Occupational Overuse Syndrome-Worksafe Australia [NOHSC:2013(1994)], 
(Ex. 500-71-2);
    <bullet> National Standard for Manual Handling and National Code of 
Practice for Manual Handling, Worksafe Australia. 1990 (Ex. 500-71-4);
    <bullet> Occupational Overuse Syndrome: Guidelines for Prevention 
and Management, Occupational Safety and Health Services, Department of 
Labor, New Zealand (Ex. 500-71-12);
    <bullet> Ergonomics (MSI) Requirements, British Columbia, Canada 
(Ex. 32-339-1-6);

[[<strong>Page</strong> 68438]]

    <bullet> Regulations and Code of Practice, (Manual Handling) 
Occupational Health and Safety Regulations 1988. Victoria, Canada. (Ex. 
500-71-17);
    <bullet> European Communities Council Directive on Manual Handling 
(Ex. 32-339-1-12);
    <bullet> American Conference of Governmental Industrial Hygienists, 
Threshold Limit Value (TLV) Committee, Nov. 13, 1999. Notice of Intent 
to Establish a Threshold Limit Value, Hand Activity Level (Ex. 32-339-
1-63);
    <bullet> American Conference of Governmental Industrial Hygienists. 
1987. Ergonomic Interventions to Prevent Musculoskeletal Injuries in 
Industry (Ex. DC-386, Tr. 16291-335);
    <bullet> American Industrial Hygiene Association. 1994. Ergonomic 
Guide Series (Ex. 32-133-1);
    <bullet> American National Standards Institute (ANSI) draft 
Ergonomic Standard, Z-365 (1998) (Ex.26-1264).
    Furthermore, the vast majority of the many job evaluation tools 
found in the record and reviewed by the Agency collectively address 
these same risk factors covered under the final rule (Exs. 26-521, 26-
1421, 26-1008, 26-883, 26-500-71-92). Also, studies using specific 
interventions to reduce biomechanical load address these same risk 
factors (see section VI, Risk Assessment).

B. Overview of Evidence of Health Effects for Work-Related 
Musculoskeletal Disorders

    A substantial body of scientific evidence supports OSHA's effort to 
provide workers with ergonomic protection (see the Health Effects 
Appendix of the proposal preamble, and the Health Effects Summary, Risk 
Assessment, and Significance of Risk sections of this preamble, below). 
This evidence strongly supports two basic conclusions: (1) there is a 
positive relationship between exposure to biomechanical risk factors 
and development of work-related musculoskeletal disorders and (2) 
ergonomics programs and specific ergonomic interventions can reduce 
these risks. Although it is recognized that many individual and non-
biomechanical workplace factors (such as psychosocial factors) also 
contribute to the total risk, exposure to biomechanical factors has 
been shown to contribute to the risk independently from other causal 
factors; these findings support the appropriateness of designing 
interventions that reduce exposures to biomechanical factors as a 
strategy for reducing risk of MSDs.
    This section presents an overview of the health evidence summarized 
from the proposal (64 FR 65865-65926; Ex. 27-1), updates that evidence 
with more recent information brought to the Agency's attention during 
the rulemaking process, and presents some additional information and 
conclusions as to the adequacy and quality of the overall scientific 
data base used for the final rule. In developing its review of the 
scientific evidence, the Agency has relied on almost 200 
epidemiological studies that describe the prevalence or incidence of 
MSDs among workers who have been exposed to biomechanical risk factors. 
Several of these (see Part G of the Health Effects sections) 
simultaneously evaluated the effects of biomechanical and psychosocial 
factors in the workplace; these studies generally represent the most 
recent and best-designed epidemiological studies.
    In addition to epidemiological studies, OSHA has reviewed a 
considerable amount of information and studies that describe the 
biomechanical aspects of MSD etiology, along with studies that have 
been conducted to elucidate the physiological responses of tissues to 
biomechanical stress. Much of this information was presented in detail 
in OSHA's Health Effects Appendices (Ex. 26-1), prepared at the time of 
the final rule. OSHA has since supplemented this information with 
additional material contained in the rulemaking record.
    In compiling and evaluating the scientific evidence for its 
proposed ergonomic program standard OSHA made use of the two major 
reviews of the evidence for work-relatedness of MSDs available at that 
time, NIOSH's ``Musculoskeletal Disorders and Workplace Factors: A 
Critical Review of the Epidemiologic Evidence for Work-Related 
Musculoskeletal Disorders of the Neck, Upper Extremity, and Low Back'' 
(Bernard, 1997; Ex. 26-1) and the National Research Council/National 
Academy of Sciences' ``Workshop on Work-Related Musculoskeletal 
Injuries: The Research Base'' (Ex. 26-37). Because OSHA's reliance on 
these two important works generated a considerable amount of comment 
and testimony, these two reviews are described in detail here. However, 
throughout this Health Effects section, OSHA has made use of several 
other scientific reviews of the literature as well.
    The National Institute for Occupational Safety and Health (NIOSH) 
conducted a scientific review of hundreds of peer-reviewed studies, and 
evaluated the evidence for work-related musculoskeletal disorders of 
the neck, upper extremity, and low back (Bernard, 1997; Ex.26-1). The 
focus of this review was the epidemiology literature, the goal of which 
is to identify factors that are associated (positively or negatively) 
with the development of recurrence of adverse medical conditions. This 
evaluation and summary of the epidemiologic evidence focuses chiefly on 
disorders that affect the neck and the upper extremity, including 
tension neck syndrome, shoulder tendinitis, epicondylitis, carpal 
tunnel syndrome, and hand-arm vibration syndrome, which have been the 
most extensive studies in the epidemiologic literature. The document 
also reviews studies that have dealt with work-related back pain and 
that address the way work organization and psychosocial factors 
influence the relationship between exposure to physical factors and 
work-related MSDs. The literature about disorders of the lower 
extremity is outside the scope of the NIOSH review, and OSHA has done 
its own analysis of that literature. The NIOSH work is the most 
comprehensive review of this scientific literature to date.
    A search strategy of bibliographic databases identified more than 
2,000 studies. Studies were included if they evaluated exposure so that 
some inference could be drawn regarding repetition, force, extreme 
joint posture, static loading or vibration, and lifting tasks. Studies 
in which exposure was measured or observed and recorded for the body 
part of concern were considered superior to studies that used self-
reports or occupational/job titles as surrogates for exposure.
    Because of the focus on the epidemiology literature, studies that 
were laboratory-based or that focused on MSDs from a biomedical 
standpoint, dealt with clinical treatment of MSDs, or had other 
nonepidemiologic orientation were eliminated from further consideration 
for this document. This strategy yielded over 600 studies for inclusion 
in the detailed review process. Population-based studies of MSDs, case-
control studies, cross-sectional studies, longitudinal cohort studies, 
and case series were included.
    The first step in the analytical process was to classify the 
epidemiologic studies by the following criteria:

    <bullet> The participation rate was <gr-thn-eq> 70%. This 
criterion limits the degree of selection bias in the study.
    <bullet> The health outcome was defined by symptoms and physical 
examination. This criterion reflects the preference of most 
reviewers to have health outcomes that are defined by objective 
criteria.
    <bullet> The investigators were blinded to health or exposure 
status when assessing health or exposure status. This criterion 
limits

[[<strong>Page</strong> 68439]]

observed bias in classifying exposure or disease.
    <bullet> The joint (part of body) under discussion was subjected 
to an independent exposure assessment, with characterization of the 
independent variable of interest (such as repetition or repetitive 
work). Studies that used either direct observation or actual 
measurements of exposure were considered to have a more accurate 
exposure classification scheme, whereas studies that exclusively 
used job title, interviews, or questionnaire information were 
assumed to have less accurate exposure information.

    During review of the studies, the greatest qualitative weight was 
given to studies that had objective exposure assessments, high 
participation rates, physical examinations, and blinded assessment of 
health and exposure status.
    The second step of the analytical process was to divide the studies 
into those with statistically significant associations between 
exposures and health outcomes and those without statistically 
significant associations. The associations were then examined to 
determine whether they were likely to be substantially influenced by 
confounding or other selection bias (such as survivor bias or other 
epidemiologic pitfalls that might have a major influence on the 
interpretation of the findings). These include the absence of 
nonrespondent bias and comparability of study and comparison groups.
    The third step of the analytical process was to review and 
summarize studies with regard to the epidemiologic criteria for 
causality: strength of association, consistency in association, 
temporal association, and exposure-response relationship. No single 
epidemiologic study will fulfill all criteria to answer the question of 
causality. However, results from epidemiologic studies can contribute 
to the evidence of causality in the relationship between workplace risk 
factors and MSDs. The exposures examined for the neck and upper 
extremity were repetition, force, extreme posture, and segmental 
vibration.
    Using the epidemiologic criteria for causality as the framework, 
the evidence for a relationship between workplace factors and the 
development of MSDs from epidemiologic studies is classified into one 
of the following categories: strong evidence of work-relatedness, 
evidence of work-relatedness, insufficient evidence of work-
relatedness, evidence of no effect of work factors. The amount and type 
of evidence required for each category is described below:

    Strong evidence of work-relatedness. A causal relationship is 
known to be very likely between intense or long-duration exposure to 
the specific risk factor(s) and MSD when the epidemiologic criteria 
of causality are used. A positive relationship has been observed 
between exposure to the specific risk factor and MSD in studies in 
which chance, bias, and confounding factors could be ruled out with 
reasonable confidence in at least several studies.
    Evidence of work-relatedness. Some convincing epidemiologic 
evidence shows a causal relationship when the epidemiologic criteria 
of causality for intense or long-duration exposure to the specific 
risk factor(s) and MSD are used. A positive relationship has been 
observed between exposure to the specific risk factor and MSDs in 
studies in which chance, bias, and confounding factors are not the 
likely explanation.
    Insufficient evidence of work-relatedness. The available studies 
are of insufficient number, quality, consistence, or statistical 
power to permit a conclusion regarding the presence or absence of a 
causal association. Some studies suggest a relationship to specific 
risk factors, but chance, bias, or confounding may explain the 
association.
    Evidence of no effect of work factors. Adequate studies 
consistently show that the specific workplace risk factor(s) is not 
related to development of MSD.

    The above framework provides an indication of the selection 
criteria NIOSH used in identifying studies for inclusion in their 
review. Studies were included if the exposed and referent populations 
were well defined, and if they involved neck, upper-extremity, and low-
back MSDs measured by well-defined, explicit criteria determined before 
the study. Studies whose primary outcomes were clinically relevant 
diagnostic entities, generally had less misclassification and were 
likely to involve more severe cases. Studies whose primary outcomes 
were the reporting of symptoms generally had more misclassification of 
health status and a wider spectrum of severity.
    Care should be taken when interpreting some study results regarding 
individual workplace factors of repetition, force, extreme or static 
postures, and vibration. As Kilbom (1994; Ex. 26-1352) stated, these 
factors occur simultaneously or during alternating tasks within the 
same work, and their effects concur and interact. A single odds ratio 
(OR) for an individual risk factor may not accurately reflect the 
actual association, as not all of the studies derive ORs for 
simultaneously occurring factors. Thus these studies were not only 
viewed individually (taking into account good epidemiologic principles) 
but together for making broader interpretations about epidemiologic 
causality. Many investigators did not examine each risk factor 
separately but selected study and comparison groups based on 
combinations of risk factors (such as workers in jobs involving high 
force and repetition compared with workers having no exposure to high 
force and repetition.)
    Based on the epidemiologic criteria described above, NIOSH made the 
following findings:
    Strong evidence of work-relatedness exists for the following 
associations:
    <bullet> High levels of static contraction, prolonged static loads, 
extreme working postures involving the neck/shoulder muscles and an 
increased risk for neck/shoulder MSDs;
    <bullet> Exposure to a combination of risk factors (e.g., force and 
repetition, force and posture) and CTS;
    <bullet> Job tasks that require a combination of risk factors 
(e.g., highly repetitious, forceful hand/wrist exertions) and hand/
wrist tendinitis;
    <bullet> High level exposure to hand-arm vibration and vascular 
symptoms of hand-arm vibration syndrome;
    <bullet> Work-related lifting and forceful movements;
    <bullet> Exposure to whole-body vibration and low-back disorder.
    2. Evidence exists for the following associations:
    <bullet> Highly repetitive work and neck and neck/shoulder MSDs, 
considering both repetitive neck movements (using frequency and 
duration of movements) and repetitive work involving continuous arm or 
hand movements;
    <bullet> Forceful exertion and neck MSDs, with ``forceful work'' 
involving forceful arm or hand movements, which generate loads to the 
neck/shoulder area;
    <bullet> Highly repetitive work and shoulder MSDs;
    <bullet> Repeated or sustained shoulder postures with greater than 
60 degree of flexion or abduction and shoulder MSDs;
    <bullet> Highly repetitive work, both alone and in combination with 
other factors and carpal tunnel syndrome;
    <bullet> Work involving hand/wrist vibration and CTS;
    <bullet> Any single factor (repetition, force and posture) and 
hand/wrist tendinitis;
    <bullet> Work-related awkward postures and low-back disorders.
    3. Insufficient evidence of work-relatedness exists for the 
following associations:
    <bullet> Vibration and neck disorders;
    <bullet> Force and shoulder MSDs;
    <bullet> Extreme posture and CTS.
    The NIOSH review (Bernard, 1997; Ex. 26-1) is an authoritative, 
systematic, critical review of the epidemiologic evidence regarding 
work-related risk

[[<strong>Page</strong> 68440]]

factors and their relationship to MSDs of the neck, shoulder, elbow, 
hand/wrist, and low back. In considering its purpose, the authors 
state:

    This review of the epidemiologic literature may assist national 
and international authorities, academics, and policy makers in 
assessing risk and formulating decisions about future research or 
necessary preventive measures.

    In 1998, the National Institutes of Health asked the National 
Academy of Sciences/National Research Council (NRC) to assemble a group 
of experts to examine the scientific literature relevant to the work-
related musculoskeletal disorders of the lower back, neck and upper 
extremities. A steering committee was convened to design a workshop, to 
identify leading researchers on the topic to participate, and to 
prepare a report based on the workshop discussions and their own 
expertise. Additionally, the steering committee was asked to address, 
to the extent possible, a set of seven questions posed by Congress on 
the topic of musculoskeletal disorders. The steering committee includes 
experts in orthopedic surgery, occupational medicine, epidemiology, 
ergonomics, human factors, statistics, and risk analysis (NRC, 1999; 
Ex. 26-37). Note: The steering committee's report was published in 
1998, and was referred to in OSHA's proposal as Ex. 26-37. In the final 
rule, Ex. 26-37 refers to the final report, (Work-Related 
Musculoskeletal Disorders: Report, Workshop Summary, and Workshop 
Papers, National Research Council, 1999; Ex. 26-37), which includes the 
steering committee's report, a summary of the proceedings of the 2-day 
workshop (Work-Related Musculoskeletal Injuries: The Research Base), 
and the workshop papers.
    The charge to the steering committee, reflected in the focus of the 
workshop, was to examine the current state of the scientific research 
base relevant to the problem of work-related musculoskeletal disorders, 
including factors that can contribute to such disorders, and strategies 
for intervention to ameliorate or prevent them. The NAS/NRC organized 
their examination of the evidence of factors that potentially 
contribute to musculoskeletal disorders:
    (1) Biological responses of tissues to biomechanical stressors;
    (2) Biomechanics of work stressors, considering both work and 
individual factors, as well as internal loads;
    (3) Epidemiologic perspectives on the contribution of physical 
(biomechanical) factors;
    (4) Non-biomechanical (e.g., psychological, organizational, social) 
factors; and
    (5) Interventions to prevent or mitigate musculoskeletal disorders.
    For four of these topics, discussions at the workshop centered on a 
paper (or papers) commissioned for the workshop, followed by the 
comments of invited discussants. For the epidemiology of physical 
factors, the steering committee used a panel format to take advantage 
of a recent review of this literature, the NIOSH review, published in 
1997, and previously discussed here.
    Use of this broad approach provided for the examination of evidence 
from both basic and applied science and a wide variety of 
methodologies, and considered sources of evidence that extend well 
beyond the epidemiologic literature alone. In determining whether 
scientific evidence supports a causal claim for risk factors and work-
related musculoskeletal disorders, the NAS/NRC steering committee 
considered the following five criteria:
    <bullet> Temporal ordering requires that the cause be present 
before the effect is observed.
    <bullet> Cause and effect covary. For example, when no force is 
applied to a tendon, it remains in a relaxed state; in the presence of 
the cause (a force), the tendon responds.
    <bullet> Absence of other plausible explanations for the observed 
effect. Adequate controlling of confounding factors by the design of 
the experiment or observation makes other explanations for the observed 
effect less likely.
    <bullet> Temporal contiguity, amplifies the first (temporal 
ordering). To the extent that the effect follows the cause closely in 
time, the plausibility that other factors are operative is reduced.
    <bullet> Congruity between the cause and effect, that is the size 
of the cause is related to the size or magnitude of the effect.
    In its report, the NRC noted that in addressing complex research 
questions, such as relationships between risk factors and work-related 
musculoskeletal disorders, single studies rarely, if ever, provide 
conclusiveness of a causal relationship. Replication and synthesis of 
evidence across studies, preferably with studies that use a variety of 
methods (each with different strengths and weaknesses) strengthens 
causal associations. In performing such synthesis, studies that most 
completely satisfy the five criteria specified above should be given 
greatest weight. Inferential strength is gained by examining the 
evidence from a variety of theoretical perspectives, as well as a 
variety of research methods. A major strength of the NRC/NAS review is 
that it takes this broad approach toward evaluating the relevant 
scientific evidence.
    In evaluating the epidemiologic literature and NIOSH's review of 
that literature, the NRC/NAS steering committee identified the 
following limitations in the epidemiologic evidence:

    <bullet> Temporal contiguity between the stressors and onset of 
effects, as well as amelioration after reduction of stressors, could 
not always be established, nor could the clinical course of the 
observed effects;
    <bullet> Methods used for the assessment of exposures and health 
outcomes vary, rendering the task or merging and combining evidence 
more challenging than in some other areas of occupational risk 
assessment;
    <bullet> Lack of baseline prevalence and incidence data for the 
general population.
    Despite these limitations, the steering committee reached the 
following conclusions regarding the epidemiologic evidence:
    <bullet> Restricting our focus to those studies involving the 
highest levels of exposure to biomechanical stressor of the upper 
extremity, neck, and back and those with the sharpest contrast in 
exposure among the study groups, the positive relationship between 
the occurrence of musculoskeletal disorders and the conduct of work 
is clear. * * * (T)hose associations identified by the NIOSH review 
(NIOSH, 1997; Ex 26-1) as having strong evidence are well supported 
by competent research on heavily exposed populations.
    <bullet> There is compelling evidence from numerous studies that 
as the amount of biomechanical stress is reduced, the prevalence of 
musculoskeletal disorders at the affected body region is likewise 
reduced. This evidence provides further support for the relationship 
between these work activities and the occurrence of musculoskeletal 
disorders.
    <bullet> Evidence of a role for biomechanical stress in the 
occurrence of musculoskeletal disorders among populations exposed to 
low levels of biomechanical stressors remains less definitive, 
though there are some high-quality studies suggesting causal 
associations that should serve as the basis for further 
investigation. In cases of low levels of biomechanical stress, the 
possible contribution of other factors to musculoskeletal disorders 
is important to consider. The report then addresses other factors, 
including individual factors (e.g., age, prior medical conditions); 
and organizational and social factors (e.g., job content and 
demands, job control and social support).

    The conclusions from the NAS/NRC report (Ex. 26-37) from the 
biomechanical literature are presented (in brief) in the previous 
discussion of ``force''in Section A.
    In setting forth its conclusions on musculoskeletal disorders in 
the workplace, NRC/NAS steering committee notes that it has:

supplemented our professional expertise with workshop presentations, 
commissioned papers and other submissions, and

[[<strong>Page</strong> 68441]]

discussions with invited workshop participants.

and, as a result concluded (in summary):

    <bullet> There is a higher incidence of reported pain, injury, 
loss of work, and disability among individuals who are employed in 
occupations where there is a high level of exposure to physical 
loading than for those employed in occupations with lower levels of 
exposure.
    <bullet> There is a strong biological plausibility on the 
relationship between the incidence of musculoskeletal disorders and 
the causative exposure factors in high-exposure occupational 
settings.
    <bullet> Research clearly demonstrates that specific 
interventions can reduce the reported rate of musculoskeletal 
disorders for workers who perform high-risk tasks.
    <bullet> Research can (1) provide a better understanding of the 
mechanisms that underlie the established relationships between 
causal factors and outcomes; (2) consider the influence of multiple 
factors (mechanical, work, social, etc.) on symptoms, injury, 
reporting, and disability; (3) provide more information about the 
relationship between incremental change in load and incremental 
biological response as a basis for defining the most efficient 
interventions; (4) improve the caliber of measurements for risk 
factors, outcome variables, and injury data collection systems; and 
(5) provide better understanding of the clinical course of these 
disorders.

    The relevant scientific literature has been thoroughly and 
systematically evaluated by two highly-reputable and independent 
scientific bodies and their experts, who used different approaches to 
evaluate the literature from different scientific disciplines (while 
allowing for some overlap), using causality criteria from two related 
but different frameworks. The NIOSH and NRC/NAS reviews offer two 
distinct but consistent sets of conclusions that can be drawn from the 
literature on work-related musculoskeletal disorders. Generally, both 
reviews agree that the scientific evidence provides compelling support 
for a higher risk of work-related musculoskeletal disorders and the 
loss of work, and disability among individuals who are employed in 
occupations where there is a high level of exposure to physical loading 
(biomechanical factors), and that evidence clearly demonstrates that 
specific interventions can reduce the reported rate of musculoskeletal 
disorders for workers who perform high-risk tasks.
    In the face of overwhelming evidence that biomechanical/physical 
risk factors in the workplace cause MSDs, some critics, such as UPS 
argue that there is not even one study which demonstrates that 
repetitive motion causes injury (Ex. 32-241-4). When asked at the 
hearing whether he agreed with this UPS position, Dr. Robert McCunney, 
representing the American College of Occupational and Environmental 
Medicine replied ``I find this statement incredulous'' (Tr. 7662). Dr. 
McCunney then continued in his testimony to state that there is 
sufficient scientific literature showing that repetitive motion 
activities can lead to MSDs. According to Dr. Barbara Silverstein, of 
the Washington State Department of Labor and Industries, scientific 
researchers who hold to the UPS view that there is no evidence that 
repetitive movements causes injury ``are in a minority'' (Tr. 17415). 
Likewise, in response to the same question regarding the UPS 
contention, Dr. Thomas Armstrong (University of Michigan) defended the 
scientific evidence that repetitive movements can result in injury, by 
replying:

    There are physiological studies looking at repetitive work as it 
contributes to muscle fatigue and changes in histology of muscle 
tissue. There are epidemiological studies that have looked at the 
relationship between various exposures to repetition and a variety 
of musculoskeletal types of disorders. These studies from different 
disciplines all come together and support the same conclusion.

    Professional and scientific organizations supporting OSHA's 
determinations regarding the scientific basis underlying the standard 
include:
    <bullet> American Association of Occupational Health Nurses (Ex. 
30-2387)
    <bullet> American College of Occupational and Environmental 
Medicine (Ex. 30-4468, Tr. 7637-7690)
    <bullet> American Conference of Governmental Industrial Hygienists 
(Ex. DC-386, Tr. 16291-335)
    <bullet> American Industrial Hygiene Association (Ex. 32-133-1, Tr. 
16464-72, Tr. 16518-27)
    <bullet> American Nurses Association (Ex. 30-3686, Tr. 15875-95)
    <bullet> American Occupational Therapy Association (Ex. 30-4777, 
Tr. 18095-18121)
    <bullet> American Public Health Association (Ex. 30-626, Tr. 17649-
17704)
    <bullet> American Society of Safety Engineers (Ex. 32-21-1-2; Tr. 
11612)
    <bullet> Human Factors and Ergonomics Society (Ex. 502-472)
    <bullet> National Association of Orthopedic Nurses (Tr. 10578-
10588)
    <bullet> The American Society of Plastic and Reconstructive Surgery 
(Ex. DC-46, Tr. 1534)
    OSHA finds no merit to assertions that there is insufficient 
science on which to base its proposal and subsequent final rule. 
Rather, the Agency finds that the body of scientific evidence on which 
OSHA based this rule is vast and conclusive. This position was 
supported by many witnesses and multiple pages of hearing testimony, 
and added to the substantial base of scientific literature that OSHA 
relied on for the publication of it's proposal. And, although there 
have been critics to OSHA's actions, they are in fact, in the vast 
minority. The science overwhelmingly supports reducing biomechanical 
risk factors in the workplace as an effective approach to reducing 
work-related musculoskeletal disorders.
    When asked ``whether ACOEM believes that detection and elimination 
of these ergonomic risk factors at work can result in a reduction in 
the number of these disorders'' during the hearing, Dr. McCunney 
replied ``Very much so'' (Tr. 7663).
    The following parts of this section discuss the evidence for the 
work-relatedness of MSDs. Tables V-1 through V-8 summarize some key 
aspects of the epidemiological studies that investigate MSDs, such as 
the occupations examined, the biomechanical risk factors they were 
exposed to, whether exposures were directly observed or measured during 
the study, and whether the health outcomes were verified by trained 
medical personnel during physical examination. The last column provides 
a quantitative (if available) risk measure or range of risk measures 
reported in each study that best captures the strength of the 
association between the studied biomechanical risk factor(s) and health 
outcome. Study entries with a single odds (or prevalence) ratio 
examined the relative risk between an exposed group of workers and 
unexposed referent population. For most studies, the risk values and 
confidence intervals were obtained from tables found in the 1997 NIOSH 
review (Ex. 26-1). For the additional studies not reviewed by NIOSH, 
OSHA obtained risk values from the material submitted in the docket.
    Many studies reported risk ratios for multiple exposed groups and/
or several indicators of exposure to biomechanical risk factors. In 
these cases, the range of reported risk measures were provided in the 
summary tables. OSHA did not include in this range; (1) risks ratios 
(high or low) that were inherently unstable because they were based on 
very low numbers of cases; (2) risk ratios that did not reflect 
differences in biomechanical risk factors; and (3) risk ratios in which 
the variation in exposure between groups were so small that a 
difference in MSD prevalence

[[<strong>Page</strong> 68442]]

would have been difficult to detect. The 95 percent confidence interval 
for the upper end of the risk range were also recorded on the tables.
    Some studies on the tables did not report odds (or prevalence) 
ratios, even though they may have established a statistically 
significant association between biomechanical risk factor and health 
outcome. Often, the association was expressed as a regression analysis 
between a particular biomechanical measurement and number of MSD cases. 
Sometimes, the study did not provide a risk measure but simply reported 
the MSD prevalence of different groups of exposed workers. These study 
entries were designated with a NR (risk ratio not reported).

C. Disorders of the Neck and Shoulder

    MSDs of the neck and shoulder that have been documented in the 
scientific literature include the clinically well-defined disorders, 
such as tendinitis, and the less clinically well-defined soft tissues 
disorders, such as tension-neck syndrome (Gerr 1991, Ex. 26-1208; Moore 
1992, Ex. 26-984). MSDs of the neck and shoulder often involve tendons, 
muscles, and bursa; nerves and blood vessels may also be affected. 
Because of the simultaneous involvement of several regional structures 
in neck and shoulder MSDs, there may be positive signs and/or symptoms 
in more than one structure. For example, strong abduction or extension 
of the upper arm, as well as awkward postures of the neck, can compress 
parts of the brachioplexus under the scalene muscles and other 
anatomical structures. This compression can result in nerve and/or 
blood vessel damage or in eventual damage to the tissues served by 
these nerves and vessels.

Neck and Upper Back

    In this section, OSHA summarizes the evidence for an increased risk 
for musculoskeletal disorders of the neck and upper back associated 
with exposure to biomechanical risk factors in the workplace. This 
region (neck and upper back) includes the cervical and thoracic spine 
(spine above the lumbar or low back) and supporting structures and 
tissues. The scientific literature frequently refers to this region as 
``Neck and Neck/Shoulder,'' or as ``Neck and Shoulder'' or as ``Neck 
and Upper Back.'' With respect to the epidemiologic literature, the 
studies NIOSH referred to in it's ``Neck and Neck/Shoulder'' section 
are included in this section. A summary of the evidence regarding the 
shoulder only is reviewed in the separate section following this one. 
For greater detail on the scientific evidence summarized here see 64 FR 
65865-65926).
    The lifetime prevalence of neck pain is estimated at 40% to 50%, 
with a 1-year prevalence of about 20% (Takala et al.1982, Ex. 26-1169). 
Using a definition of 2 weeks of neck pain, the prevalence among men 
and women aged 25 to 74 years in the NHANES Survey II (1976 to 1980) 
was 8.2% (Praemer, Furner, and Rice 1992, Ex. 26-869). Chronic neck 
pain is estimated to be present in up to 9% to 10% of males and 12% to 
14% of females (Makela et al.1991, Ex. 26-980; Revel et al.1994, Ex. 
26-195). Individuals in the 4th to 6th decades of life have the 
greatest incidence of neck disorders (Makela et al.1991, Ex. 26-980; 
Praemer, Furner, and Rice 1992, Ex. 26-869).
    What is known about the course of neck pain? It is estimated that 
90% of patients with acute neck pain are improved within 2 months 
(Borenstein, Wiesel, and Boden 1996, Ex. 26-1394). The Quebec Spinal 
Study (1987, Ex. 26-494) series of individuals with work-related spinal 
disorders suggests that 74% recover by 7 weeks. A 10-year outcome study 
of patients with neck pain revealed that 79% had less pain and 43% were 
pain-free. However, 32% still experienced moderate or severe pain (Gore 
et al.1987, Ex. 26-127). With regard to work-related MSDs, some 
intervention studies have suggested that workplace modifications may 
decrease both symptoms of neck pain and/or muscle activity as recorded 
by EMG (Aaras 1994a, Ex. 26-892; Aaras et al.1998, Ex. 26-597; Schuldt 
et al.1987, Ex. 26-670).
    The extent to which neck pain occurs in or affects workers depends 
to a great extent on the terms used to define the pain, in terms of 
intensity and duration, and on the methods used in determining the 
presence or occurrence (self-report, interview, or physical 
examination). Point prevalence of neck pain in a general U.S. 
population has been reported at 10%, matching point prevalence reports 
of workers in an aeroengineering factory and exceeding a 4% prevalence 
reported in a group of textile workers (Palmer et al.1998, Ex. 26-1529 
). Other estimates found in the literature include 68% for female and 
47% for male Swedish industrial workers performing unskilled tasks (3-
month prevalence of MSDs in the neck and in the thoracic 
back)(Bjorksten et al.1996, Ex. 26-604). One-year prevalence of neck 
pain or neck and upper-back pain was 16% in a group of electricians, 
excluding neck pain associated with traumatic injury, and 38% with a 
less restrictive definition (Hunting, et al.199, Ex. 26-1273); 26% and 
18%, in the Danish wood and furniture industry respectively 
(Christensen, Pedersen, and Sjogaard 1995, Ex. 26-95). Prevalence of 
regular discomfort in the posterior neck region was 6.3%, and 9.1% in 
the upper-back region, in a group of chicken-processing workers. 
However, the lifetime prevalence was 36%, the point prevalence was 18%, 
and 9% had sought medical treatment for discomfort (Buckle 1987, Ex. 
26-938).
    Many studies of neck pain have focused on employees working in 
health care. Milerad and Ekenvall (1990, Ex. 26-1291) reported cervical 
symptom prevalence of 45% of male dentists and 63% of female dentists, 
rates that were 2.6 and 2 times those of male and female pharmacists, 
respectively. Twelve-month prevalence of self-reported neck pain was 
63.1% in a group of medical secretaries and hospital office personnel 
(Linton and Kamwendo 1989, Ex. 26-978).
    With regard to work-related cervical spine disorders, the Quebec 
Spinal Study (1987, Ex. 26-494) observed an annual incidence of over 
0.1%. However, Bjorksten et al.(1996, Ex. 26-604) reported a 68%, 3-
month prevalence for neck pain in industrial workers performing 
unskilled tasks, more than double the rate in the general population. 
Certain jobs appear to have greater associations with neck pain than 
others, with the lifetime prevalence of neck and shoulder symptoms 
reaching 81% in machine operators, 73% in carpenters, and 57% in office 
workers (Tola et al.1988, Ex. 26-1018). It must be understood that 
there may be an underestimation of work-relatedness of neck pain since 
the onset of pain may, at times, be delayed and the work relation 
uncertain.
    Tension neck syndrome is a myofascial (muscle pain) localized in 
the shoulder and neck region (Hagberg 1984; Ex. 26-1271). Also called 
scapulocostal syndrome (Fine and Silverstein 1998; Ex. 38-444), these 
syndromes are often characterized by diffuse tenderness over the 
muscle, rather than the tendon origin, and activity limitation. The 
pathophysiology is unknown; however, a number of mechanism have been 
proposed, including inflammation. Two types of muscle activity may be 
important in work-related disorders: low-force, prolonged muscle 
contractions (e.g., in office workers moderate neck flexion while 
working on a visual display terminal (VDT) for many hours without rest 
breaks); and infrequent or frequent high-force muscle contractions 
(intermittent use of heavy tools) in

[[<strong>Page</strong> 68443]]

overhead work). Sustained static contractions can lead to increases in 
intramuscular pressure, which in turn may impair blood flow to cells 
within the muscle (Hagberg, 1984; Ex. 26-1271).
    Motor nerve control of the working muscle may be important in 
sustained static contractions since even if the relative load on the 
muscle as a whole is low, the active part of the muscle may be working 
close to it's maximal capacity. Thus, small areas of large muscles such 
as the trapezius may have disturbances in microcirculation that might 
contribute or cause the development of muscle damage (red ragged 
fibers), reduce strength, higher levels of fatigue, sensitization of 
pain receptors in the muscle, and pain at rest (Armstrong, Buckle and 
Fine 1993, as cited in Fine and Silverstein 1998, Ex. 38-444). High 
levels of tension (strong contractions) can lead to muscle fiber Z-line 
rupture, muscle pain, and large, delayed increases in serum creatine 
kinase. These changes are reversible and can be completely repaired, 
often leading the muscle to be stronger. It is hypothesized that if 
damage occurs daily due to work activity, the muscle may not be able to 
repair the damage as fast as it occurs, leading to chronic muscle 
damage or dysfunction. The mechanism of this damage at the cellular 
level is not understood (Armstrong, Buckle and Fine, 1993 as cited in 
Fine and Silverstein 1998, Ex. 38-444).
    Hagberg (1984, Ex. 26-1271; and Hagberg and Wegman 1987, as cited 
in Magnusson and Pope Ex. 38-450) described three possible 
pathophysiological mechanisms for occupational muscle-related 
disorders, such as tension neck syndrome. The first is mechanical 
failure, due to temporary high local stress involving eccentric 
contractions on the shoulders, such as in workers unaccustomed to the 
work task. The second is local decreased blood flow (ischemia), as seen 
in assembly workers whose tasks involved dynamic, frequent contractions 
above 10 to 20% of the maximum voluntary contraction and few rest 
breaks. Both a reduction in blood flow and pathologic changes were 
found to be correlated with myalgia (muscle pain) and ragged red fibers 
in 17 patients doing repetitive assembly work (Larsson et al.1990, Ex. 
26-1141).
    The third pathophysiologic mechanism for muscle pain (Hagberg 1984, 
Ex. 26-1271) energy metabolism disturbance, occurs when energy demand 
exceeds production. Long-term static contractions of the muscles result 
in the prolonged recruitment of limited numbers of motor units, and can 
deplete available energy, producing eventual fatigue and injury (Lieber 
and Friden 1994, Ex. 26-559). Higher subjective levels of fatigue as 
well as electrophysiological evidence of fatigue are more common in 
large muscle groups, such as the neck and shoulder muscles, when 
activities are static and repetitive rather than dynamic (Sjogaard 
1988, Ex. 26-830).
    Pain arising from cervical spine skeletal structures may 
potentially originate from many locations, since sensory nerve 
innervation is present in ligaments, joint capsules, the anterior and 
posterior longitudinal ligaments, the outer third of the annulus 
fibrosus, and the vertebral body (Bogduk 1982, Ex. 26-1479; Bogduk et 
al.1988, Ex. 26-514; Hirsch, Inglemark, and Miller 1963, Ex. 26-471). 
The periosteum of the cervical vertebral body may be a source of pain, 
although some slowly progressive lesions may destroy a significant 
amount of bony tissue before they are recognized (Borenstein, Wiesel, 
and Boden 1996, Ex. 26-1394). The spinal nerve roots are the source of 
pain when there is compression, ischemia, and inflammatory or chemical 
mediators that stimulate nociceptors.
    Cervical spondylosis refers to degenerative changes in the cervical 
spine that are apparent on radiological examination (Hagberg and Wegman 
1987, Ex. 26-32). The pathogenesis of cervical spine degenerative 
disease has similarities to many other joint structures, although there 
are important differences. The cervical spine has a great deal more 
movement, achieved via gliding and sliding on adjacent structures, than 
the remainder of the spine. And not being subject to repetitive and 
impulsive loading, cervical spinal segments do not require the strength 
and stability of the lumbar-sacral spine. However, these zygoapophyseal 
joints in the cervical spine have fibrocartilagenous, meniscus-like 
structures that are capable of responding with proliferative changes 
(Bland 1994, Ex. 26-416 ). As with other joints, aging, repetitive 
motion, and some loading result in fissuring of the hyaline cartilage 
surfaces. Gradually, the hyaline cartilage develops deeper and downward 
fissuring, larger erosions, and general thinning. In the cervical 
spine, the chondrocytes proliferate in areas of fibrillation or loosely 
textured matrix (Bland 1994, Ex. 26-416). And though the matrix may 
demonstrate some attempts at repair, the repair is generally 
disorderly. Subchondral bone increases in density, followed by 
microfracturing and callus formation. New bone, called osteophytes, 
appear at the margins of the articular cartilage, and may protrude into 
the joint space or neuroforamen. If large enough, this may cause nerve 
compression. Posterior spondylotic bars, especially if combined with 
hypertrophy of the ligamentum flavum, have the potential to compress 
the spinal cord, causing symptoms of cervical myelopathy. Anatomically, 
the C4 to C5, C5 to C6, and C6 to C7 intervertebral disc spaces are 
most commonly affected by osteoarthritis and degenerative disc disease.
    Thoracic outlet syndrome (TOS) is defined as a ``neurovascular 
impingement syndrome at different anatomical levels where the brachial 
plexus and subclavian vessels may be entrapped as they pass through, en 
route from the cervical spine to the arm.'' (Hagberg et al.1995, Ex. 
26-432). The syndrome involves compression of the subclavian artery and 
the lower trunk of the brachial plexus, at one or more locations 
between the neck and the axilla. Symptoms are experienced in the upper 
extremity. Cervical syndrome is defined as ``compressions of the nerve 
root by a herniated disc or a narrowed intervertebral foramen'' 
(Hagberg et al.1995, Ex. 26-432).

Epidemiological Evidence

    Several muscles act upon the upper spine and shoulder girdle 
together; Scandanavian studies have often combined neck and shoulder 
MSDs. Neck pain and MSDs will be discussed here. Those studies that 
evaluated neck and shoulder pain and MSDs together will also be 
included. Studies that exclusively evaluate pain and MSDs of the 
shoulder will be discussed in a subsequent section. Studies that have 
evaluated objective findings and/or met diagnostic criteria for 
specific disorders have been given greater weight in this analysis.
    There have been several reviews that associate neck disorders work 
factors, such as repetition, force, static loading, neck posture, and 
heavy work (NIOSH 1997, Ex. 26-1; Grieco, et al.1998, Ex. 26-627; 
Hagberg et al.1995, Ex. 26-432; Hales and Bernard 1996, Ex. 26-896; 
Viikari-Juntura 1997, Ex. 26-905; Hagberg and Wegman 1987, Ex. 26-32). 
The majority of neck disorders involve soft tissues (muscle and 
ligament strains and sprains). Outcomes studied and reported are often 
non-specific, for example, neck pain or/or stiffness. Some studies 
relied on combination of symptoms and physical exam confirming 
tenderness in neck muscles and tendons upon palpitation and/or 
localized pain during neck movement. Many others simply relied on self-

[[<strong>Page</strong> 68444]]

reported symptoms on a questionnaire. While duration of symptoms and 
case definitions were not always completely consistent, all studies 
attempted to exclude pain and/or discomfort that was transient or less 
than significant intensity.
    In a few epidemiological studies, objective exposure measurement 
that pertained to the neck region, such as work load assessments, 
electromyography, neck angle measurement, was obtained. However in most 
studies, exposure assessments were based on job titles or self-reports. 
In some investigations the primary interest and measurement strategy 
was focused on hand/wrist region, even though neck disorders were 
studied as one of the outcomes. Hand/wrist exposures will not 
necessarily reflect the biomechanical status of the neck, and, 
therefore these studies have potential for considerable exposure 
misclassification are given less weight.
    Bernard (1997, Ex. 26-1) and NIOSH reviewed epidemiological studies 
for evidence of work-relatedness of neck and neck/shoulder 
musculoskeletal disorders. In the process of identifying papers for 
this review, Bernard (1997, Ex. 26-1) first considered the strength of 
each study based on whether it provided clear definitions of exposed 
and reference populations and clear definitions of outcomes, as well 
whether it evaluated exposures in such a way as to classify them with 
regard to force, repetition, posture, or vibration. Papers that met 
these standards were then evaluated based on four criteria: a 70% or 
better response rate in order to limit response bias, health outcome 
defined by symptoms and physical examination (PE)(1), investigators 
blinded where appropriate (exposure or health status), and the neck as 
a focus of the evaluation. Only one of the studies that focused on the 
neck and two that focused on the neck/shoulder region met all four 
criteria. The likelihood of bias in each study was examined. Finally, 
studies were summarized with respect to strength of association, 
demonstration of temporal association, consistency of association among 
studies, and exposure-response relationship.
    The NIOSH review identified 46 epidemiological studies (1976 to 
1995) reporting on the neck and 23 reporting on the neck/shoulder 
region. Of these studies, 38 were cross-sectional, 2 were case-control, 
and 6 were prospective studies. Table V-1 summarizes some key aspects 
of these investigations, such as the occupations examined, the 
biomechanical risk factors the workers were exposed to, whether 
exposures were directly observed or measured during the study, and 
whether the health outcomes were verified by trained medical personnel 
during physical examination. Thirteen of the studies directly measured 
or observed a combination of repeated arm/shoulder movements, strenuous 
work that generates loads to the neck/shoulder muscles, and extreme 
static postures. The eleven studies also used physical examination by a 
health professional to define workers with neck disorders. OSHA regards 
these investigations as more reliable than those in which direct 
exposure was not observed or in which neck injuries are self-reported. 
Twelve of the thirteen studies reported a statistically significant 
association between these disorders and physical work factors (force, 
repetitive motion, awkward posture).

                           Table V-1.--Summary of Epidemiology Studies Examining Neck and Upper Back Musculoskeletal Disorders
--------------------------------------------------------------------------------------------------------------------------------------------------------
               Study                    Job type studies     Physical factors       Exposure basis           Diagnosis         Risk Measure (95% CI) \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hunting (1981) Ex. 26-1276.........  VDT operation........  R/P                 observation..........  physical exam........  OR=9.9 *
                                                                                body posture.........                         (3.7-26.9)
Veiersted (1994) Ex. 26-1366.......  chocolate manufacture  F/R?/P              EMG..................  physical exam........  OR=6.7-7.2 *
                                                                                                                              (2.1-25.3)
Ohlsson (1995) Ex. 26-868..........  assembly line........  R/P                 neck flexion.........  physical exam........  OR=3.6 *
                                                                                cycle time...........                         (1.5-8.8)
Bergqvist (1995) Ex. 26-1195.......  VDT operators........  R/P                 observation..........  physical exam........  OR=3.6-4.4 *
                                                                                                                              (1.1-17.6)
Bergvist (1995) Ex. 26-1196........  VDT operators........  R/P                 observation..........  physical exam........  OR=6.9 *
                                                                                                                              (1.1-42.1)
Onishi (1976) Ex. 26-1222..........  film rolling.........  F?/R/P              observation..........  physical exam........  OR=3.8 *
                                                                                EMG..................                         (2.1-6.6)
Norander (1999) Ex. 38-408.........  fish processing......  R/P                 observation..........  physical exam........  OR=3.0 *
                                                                                cycle time...........                         (1.5-5.9)
Kukkonen (1983) Ex. 26-1138........  data entry...........  R?/P                posture..............  physical exam........  OR=2.3 *
                                                                                observation..........                         (1.1-4.6)
Bjelle (1981) Ex. 26-1519..........  industrial plant.....  F/R/P               flexion..............  physical exam........  NR *
                                                                                EMG..................
Jonsson (1988) Ex. 26-969; Kilbom    electronics            F/R/P               flexor MVC...........  physical exam........  NR *
 (1986) Ex. 500-41-75.                manufacture.                              flexion..............
Dimberg (1989) Ex. 26-1211.........  automotive...........  F/R/P               observation..........  physical exam........  NR*
                                                                                                                              (p0.1)
Sakakibara (1995) Ex. 26-800.......  fruit bagging........  F?/R?/P             observation..........  physical exam........  OR=1.5
                                                                                arm elevation........                         (1.0-2.3)
Rosecrance (1994) Ex. 38-203.......  newspaper work.......  F?/P/R              questionnaire........  symptoms only........  OR=29 *
Andersen (1993) Ex. 26-1502........  sewing machine.......  F/R/P?              job titles...........  physical exam........  OR=6.8 *
                                                                                                                              (1.6-28.5)
Baron (1991) Ex. 26-697............  grocery checking.....  F/R/P               job titles...........  physical exam........  OR=2.0
                                                                                                                              (0.6-2.7)
Bernard (1994) Ex. 26-842..........  newspaper publishing.  R?/P                observation..........  symptoms only........  OR=1.4 *
                                                                                                                              (1.0-1.8)
Blader (1991) Ex. 26-1215..........  sewing machine.......  R/P                 questionnaire........  physical exam........  NR *
Hales (1989) Ex. 2-3-pp............  poultry processing...  F/R                 job title............  physical exam........  OR=1.6
                                                                                                                              (0.4-3.2)
Hales (1994) Ex. 26-131............  telecommunication....  R?/P                questionnaire........  physical exam........  OR=3.8*
                                                                                                                              (1.5-9.4)

[[<strong>Page</strong> 68445]]


Hunting (1994) Ex. 26-1273.........  electrician..........  V/F/R/P             questionnaire........  symptoms only........  OR=1.6
                                                                                                                              (NR)
Kamwendo (1991) Ex. 26-1384........  medical secretary....  R/P                 questionnaire........  symptoms only........  OR=1.6*
                                                                                                                              (1.0-2.7)
Kiken (1990) Ex. 26-430............  poultry processing...  F/R                 job title............  physical exam........  OR=1.3
                                                                                                                              (0.2-11)
Knave (1985) Ex. 26-753............  VDT operation........  R/P                 questionnaire........  symptoms only........  OR=1.6
                                                                                                                              (0.4-3.2)
Kuorinka (1979) Ex. 26-639.........  scissor production...  R/P                 job title............  physical exam........  OR=4.1*
                                                                                                                              (2.3-7.5)
Luopajarvi (1979) Ex. 26-56........  food production......  F/R/P?              job title............  physical exam........  OR=1.6
                                                                                                                              (0.9-2.7)
Schibye (1995) Ex. 26-1463.........  sewing machine.......  F?/R/P?             questionnaire........  symptoms only........  OR=3.3*
                                                                                                                              (1.4-7.7)
 Liss (1995) Ex. 26-55.............  dental hygienist.....  F/R/P?              questionnaire........  symptoms only........  OR=1.7*
                                                                                                                              (1.1-2.6)
 Ohlsson (1989) Ex. 26-1290........  auto assembly........  F/R/P?              job title............  symptoms only........  OR=1.9
                                                                                                                              (0.9-3.7)
 Andersen (1993) Ex. 26-1451.......  sewing machine.......  F/R/P?              job titles...........  symptoms only........  OR=3.2-4.9*
                                                                                                                              (2.0-12.8)
 Eckberg (1995) Ex. 26-1193........  residents............  F?/R/P?             questionnaire........  symptoms only........  OR=1.2*
                                                                                                                              (1.0-1.3)
 Eckberg (1994) Ex. 26-1238........  case-control.........  F?/R/P              questionnaire........  symptoms only........  OR=3.6-15.6*
                                                                                                                              (3.2-113)
 Milerad (1990) Ex. 26-1291........  dentist..............  R/P                 questionnaire........  symptoms only........  OR=2.1*
                                                                                                                              (1.2-3.1)
 Punnett (1991) Ex. 26-39..........  meat processing......  F/R/P?              observation..........  symptoms only........  OR=0.9-1.8
                                                                                                                              (1.0-3.2)
 Rossignol (1987) Ex. 26-804.......  computer operation...  R/P                 questionnaire........  symptoms only........  OR=1.8-4.6*
                                                                                                                              (1.7-13.2)
 Viikari-Juntura (1994) Ex. 26-873.  machine operation....  F/R?/P/V            observation..........  symptoms only........  OR=3.0-4.2*
                                                                                                                              (2.0-9.0)
Wells (1983) Ex. 26-729............  letter carrier.......  F/R?/P              job title............  symptoms only........  OR=2.6 *
                                                                                                                              (1.1-6.2)
Aaras (1994) Ex. 26-892............  telephone assembly...  F/R?/P              EMG..................  symptoms only........  NR *
                                                                                muscle load..........
Ferguson (1976) Cited in Ex. 26-1..  telephone interview..  R?/P                posture measures.....  symptoms only........  NR
Maeda (1982) Ex. 26-1224...........  machine operators....  F?/R?/P?            questionnaire........  symptoms only........  NR *
Linton (1989) Ex. 26-729...........  medical secretary....  R?/P?               questionnaire........  symptoms only........  NR
Linton (1990) Ex. 26-977...........  multiple industries..  F?/R?/P             questionnaire........  symptoms only........  OR=3.5
                                                                                                                              (2.7-4.5)
Sakakibara (1987) Ex. 26-1199......  fruit bagging........  F?/R/P              neck/shoulder flexion  symptoms only........  OR=1.6
                                                                                                                              (0.4-3.2)
Welch (1995) Ex. 26-1268...........  sheet metal            F?/R/P              questionnaire........  symptoms only........  OR=7.5
                                      processing.                                                                             (0.8-68)
Yu (1996) Ex. 26-696...............  VDT operation........  R?/P                questionnaire........  symptoms only........  OR=29
                                                                                                                              (2.8-291.8)
Holmstrom (1992) Ex. 26-36.........  construction.........  F?/R?/P             questionnaire........  symptoms only........  OR=2.0 *
                                                                                                                              (1.4-2.7)
Ryan (1998) Cited in Ex. 26-1......  data processing......  R?/P                shoulder flexion.....  symptoms only........  NR*
Ohara (1976) Cited in Ex. 26-1.....  cash register........  F?/R?/P?            job title............  physical exam........  NR
Tola (1988) Ex. 26-1018............  machine operation....  F?/R?/P             job title............  symptoms only........  OR=1.8 *
                                                                                                                              (1.5-2.2)
Vihma (1982) Ex. 26-789............  sewing machine.......  R/P                 observation..........  symptoms only........  PRR=1.6 *
                                                                                cycle time...........                         (1.1-2.3)
Viikari-Juntura (2000) Ex. 500-41-   forest industry......  P/R?                questionnaire........  symptoms only........  OR=1.4
 50.
Botha (1998) Ex. 500-212-10........  nurses...............  P/F                 observation..........  symptoms only........  NR *
Bjork Csten (1996) Ex. 26-604......  metal working........  R/P                 questionnaire........  symptoms only........  NR
Ignatius (1993) Ex. 26-1389........  typists..............  F/R?/P              questionnaire........  symptoms only........  OR=3.4 *
Slov (1996) Ex. 26-674.............  sales................  P                   questionnaire........  symptoms only........  OR=2.8 *
                                                                                                                              (1.4-5.59)
--------------------------------------------------------------------------------------------------------------------------------------------------------
F=forceful exertions; R=repetitive motion; P=awkward posture; ?=presence of risk factor unclear
OR=odds ratio; PRR=prevalence rate ratio, NR=not reported;
*=p0.05
\1\ 95% confidence interval expressed for the upper end of the risk measure range


[[<strong>Page</strong> 68446]]

    The odds ratios determined from the studies ranged from 1.1 to 9.9. 
Several studies deserve special mention. Ohlsson et al.(1995, Ex. 26-
868) compared 82 female industrial workers exposed to short-cycle tasks 
(less than 30 seconds) to 64 referents with no exposure to repetitive 
work. The OR for tension neck syndrome was 3.6 (95% CI: 1.5-8.8).
    The NIOSH authors concluded that there was ``reasonable evidence'' 
for an association between highly repetitive work and neck/shoulder 
MSDs, where repetitiveness was most often defined in terms of hand 
activity. They also determined that there was ``reasonable evidence'' 
for an association between forceful exertion and neck/shoulder MSDs, 
where forceful work was conducted by the arms. They concluded there was 
``strong evidence'' for an association between static loads and neck/
shoulder MSDs, where ``static load'' referred to a static load of long 
duration, high intensity, or extreme amplitude. In many of the 
situations under study, workers were exposed to more than one of these 
physical risk factors during the course of their jobs. The NIOSH review 
found insufficient evidence of an association between vibration and 
neck disorders.
    In an earlier review, Hales and Bernard (1996, Ex. 26-896) 
concluded that neck disorders were associated with work involving 
repetitive motions, forceful repetitive work, and constrained or static 
postures, based on consistency of association across several studies. 
They noted inconsistent findings regarding neck disorder and work pace, 
which, they suggested, may be due to the many ways work pace can be 
quantified. Hales and Bernard also mentioned a consistent association 
between wearing bifocals, awkward neck postures, and neck disorders.
    Hagberg et al. (1995, Ex. 26-432) reviewed epidemiological studies 
for evidence of work-relatedness of selected musculoskeletal disorders 
of the neck: TOS (neurogenic form), cervical syndrome, and tension neck 
syndrome. In compiling a list of valid papers for their review, the 
researchers considered the strength of each study based on minimization 
of bias (selection bias, information or misclassification bias, 
confounding or effect modification bias) and study power. Studies that 
met their validity criteria were then reviewed for causality (strength 
of association, demonstration of temporal association, consistency of 
association among studies, predictive power of exposure factors, and 
plausibility.
    Hagberg et al. found six cross-sectional studies of TOS (published 
between 1979 and 1991) that met their inclusion criteria. From those 
studies they found the strength of association between work and TOS to 
be generally weak, based on low odds ratios (ORs). Since all studies 
were cross-sectional in design, temporal associations could not be 
confirmed. There seemed to be a consistent association between 
repetitive work and TOS across the studies. One study demonstrated a 
dose-response relationship between vibration and TOS. The authors also 
noted an association between TOS and age. Hagberg et al. (1995, Ex. 26-
432) concluded that the studies demonstrated the existence of a 
consistent association between repetitive arm movements, manual work, 
and TOS.
    In their review, Hagberg et al.(1995, Ex. 26-432) found twelve 
cross-sectional studies and one laboratory study of tension neck 
syndrome (published between 1976 and 1988) that met their inclusion 
criteria. From those studies, Hagberg et al.(1995, Ex. 26-432) found 
the strength of association between work and tension neck syndrome to 
be moderate, based on ORs from 3 to 7. There seemed to be a consistent 
association between work with VDTs and tension neck syndrome across 
several studies, including a determination of an OR for tension neck 
syndrome of 2.0 in keyboard operators (Hagberg and Wegman 1987, Ex. 26-
32). There also seemed to be consistent associations between tension 
neck syndrome and repetitive work and static head and arm postures. The 
authors also noted that tension neck syndrome was found more commonly 
in women, but that finding may have been confounded by differences in 
work. Hagberg et al.(1995, Ex. 26-432) concluded that the studies 
demonstrated the existence of a consistent association between 
repetitive work and tension neck syndrome caused by constrained head 
and arm postures. They also noted that tension neck syndrome had a high 
prevalence in both work and reference groups.
    Three cross-sectional studies of cervical radiculopathy (published 
between 1979 and 1983) met the criteria of Hagberg et al.They observed 
that all studies showed a low prevalence for cervical radiculopathy. 
Low numbers meant wide confidence intervals, which made results 
difficult to interpret. They concluded that more directed research 
needed to be conducted in this area.
    In a review of the epidemiological evidence for three neck-related 
MSDs, the contributors to Kourinka and Forcier (1995 Ex. 26-432) report 
consistent associations between exposures to static head and arm 
postures and outcomes of tension neck syndrome. They did not find 
convincing evidence of a connection between repetition and cervical 
radiculopathy.
    A recent review of epidemiological studies by Grieco et al.(1998, 
Ex. 26-627) concluded that cervical radiculopathy had not been shown to 
be associated with data entry work, dockers' work, or food production 
assembly line work. In contrast, tension neck syndrome was linked to 
static postures and static loads in several studies on populations of 
VDT workers, typists, and sewing machine operators. Study selection 
criteria were not discussed in that review.
    Several individual studies of workers performing heavy work 
(including meat carriers and miners) found increased ORs (most adjusted 
for age) for cervical spondylosis, as did one study of dentists. 
Viikari-Juntura (1997, Ex. 26-905) reviewed both epidemiological and 
experimental studies focused on the neck (among other regions). The 
author mentioned studies that showed associations between degenerative 
changes or neck pain and heavy work, repeated impact loading, or static 
work, whereas the OR for cervical spondylosis in cotton workers was 
0.66 (protective). The relationships between work factors and cervical 
spine arthritis have not been clarified due to (1) few studies of this 
subject, (2) a lack of universal acceptance for the criteria (e.g., 
symptoms, signs, imaging) used to make this diagnosis, and (3) cervical 
spine degenerative changes are common.
    Four additional epidemiological studies that address physical work 
factors and neck and neck/shoulder disorders were submitted into the 
OSHA docket following publication of the proposal and have been added 
to Table V-1 (Nordander et. al. 1999, Ex. 38-408; Viikari-Juntura 2000, 
Ex. 500-41-50; Botha and Bridger 1998, Ex. 500-121-10; Rosecrance et al 
1994, Ex. 38-203). OSHA found a few additional studies identified in 
the NIOSH epidemiological review for other MSDs that also addressed 
neck and neck/shoulder and are also included in Table V-1 (Dimberg 
1989, Ex. 26-1211; Ignatious 1993, Ex. 26-1389; Skov 1996, Ex. 26-674). 
Two other submitted studies contained some serious methodological flaws 
and were not included in the table (Leclerc et al., 1999, 500-118-2; 
Erikson et al., 1999, 500-118-2).
    Nordander et al.1999 (Ex. 38-408) reported on a cross sectional 
study of 13 fish processing plants, examining multiple body sites, 
including the neck and shoulder. Ninety one male and 165

[[<strong>Page</strong> 68447]]

female fish industry workers were compared to men and women with more 
varied work. The work was partly paid by the work done--piece work. 
Health outcome was based on questionnaire and physical examination. 
Exposure was assessed by questionnaire, videotaping of jobs, and the 
observational method using AET (Arbeitwissenschaftliche 
Erbehungverfahren zur Tatigkeitsanalyse) along with the NIOSH lifting 
equation. Each work task classified according to three factors: weight 
of the materials handled (1, 15, 510, 10-25, >25 kg.), cycle time (5, 
5-10, 10-60, >60); and degree of constrained neck postures (low, high, 
very high). Neck and shoulder diagnoses among the fish processors was 
found to be significantly elevated compared to the referents (OR=3.5; 
95% CI 2.3-5.3). There was significantly increased prevalence of 
shoulder tendinitis found among women fish processors (OR from 3.4 to 
4.65) compared to referents. No significant effects were found due to 
age, leisure time and smoking assessed by logistic regression. Job 
analysis found that several tasks were repetitive, performed in 
constrained work postures, with fast and continuous wrist and hand 
movements, mostly with flexed neck, arms raised and lowered 
intermittently. Because it involved a direct assessment of exposure and 
verification of neck injury by a health professional, OSHA views the 
study to be among the more reliable investigations.
    Viikari-Juntura et al.2000 (Ex. 502-11) recently published findings 
on a longitudinal study of neck pain among a cohort of 5180 workers in 
a large forest industry enterprise. Participation rate was only 43% of 
the originally selected cohort of 7000. Nonrespondents were also 
followed up--there was no difference with regard to potential 
predictors except reporting 1.5 times difficulties in coming 5 years 
due to musculoskeletal health. Four repeated questionnaires were used 
focusing on ``radiating neck pain,'' categorized as healthy (0-7 days), 
mild pain (8-30 days), and severe pain (>30 days). Validated exposure 
assessment questionnaires and psychosocial questionnaires were used. 
There were several variables related to physical strenuousness, awkward 
postures, repetitive movements, and stress. Results found a 
statistically significant dose-response relationship for neck pain and 
increasing number of hours working with the hands above the shoulder. 
The risk of neck pain also increased with increasing amounts of 
twisting movements, but for the combination of twisting of the trunk 
and stress, neck pain decreased with increasing amounts of stress.
    Rosecrance (1994, Ex 38-457) conducted a cross-sectional study of 
906 office and production workers from three medium sized newspaper 
facilities to determine the level of symptomatic workers and to compare 
the office and production workers. A participation rate of 72% was 
reported. A physical exam was given to 105 participants. Exposure was 
assessed by a self-reported job factor survey. The results found that 
workers who reported repetitive tasks had an odds ratio of 29 (CI not 
reported, p=0.01) of missing work due to neck symptoms compared to 
workers who did not report repetitive tasks. Production workers 
reported more job risk factors compared to office workers. Neck 
symptoms were the most common symptom among production workers.
    Faucett and Rempel, 1994 (Ex 38-67) carried out a cross-sectional 
study of 150 video display terminal (VDT) operators from large 
metropolitan newspaper. Participation rate was low at 56%, however, 
non-respondents had no difference in age, duration of employment, 
gender, job title, or VDT training. A questionnaire-derived health 
outcome using a body diagram was employed. Observational exposure 
assessment was performed on 70 VDT workstations, completed by trained 
independent observers working in pairs evaluating work posture, wrist, 
knee and leg contact with workstation, display and seat height, angle 
measures of wrist, elbow, shoulder, head, trunk at the hip and thigh. 
Results found that 28% met symptom criteria for MSDs of the upper torso 
and extremities. Risk of having a MSD increased with a greater number 
of daily hours of VDT use. After controlling for the ergonomic factors, 
less decision latitude on the job and less coworker support were found 
to be significantly associated with certain symptoms (numbness). The 
limitations of this study are the low participation rate, although the 
non-responders were followed up and the non-specific nature of the 
health outcome.
    Leclerc et al., 1999 ( Ex. 500-118-2) conducted a longitudinal 
study to evaluate the effects of prevention programs at the workplace 
aimed at reducing back, neck, and shoulder morbidity among active 
workers. The intervention group (294 workers) and the referent group 
(294 workers) were collapsed and analyzed as a whole. Health outcome 
was based on two questionnaires. Questions ``focused more on the 
potential risk factors for low back pain, such as bending forward and 
backward, twisting, and handling of materials.'' The authors note that 
``the role of specific occupational risk factors of neck disorders, 
such as awkward postures of the head and neck and static postures, was 
not studied because these variables were not included in the 
questionnaire.'' Analyses were performed with ``occupation'' as a crude 
indicator of occupational exposure. Female gender, older age, headaches 
or pain in the head, psychological distress, and psychosomatic problems 
were predictors of neck pain. This study found that there was no 
significant difference in occurrence of neck pain among the different 
occupations--hospital workers, warehouse workers, and office workers. 
This is not surprising, as many studies have found increased rates of 
neck symptoms in these occupational groups. What is lacking in this 
study, as admitted by the authors, is adequate assessment of risk 
factors known to be associated with neck MSDs. The poor exposure 
assessment concerning occupational factors does not detract from the 
relationship of exposure to certain work factors and neck disorders. 
Because of its failure to address specific work factors related to neck 
disorders, OSHA does not regard this study as adequate and it was not 
included in Table V-1.
    Eriksen et al., 1999 (Ex. 500-118-2) carried out a community-based 
4-year prospective study of 1429 working Norwegians who completed a 
questionnaire in 1990, and returned a second questionnaire 4 years 
later. The participation rate was 67% of original group in 1990; 79.8% 
of working group from 1990 responded to 2nd questionnaire in 1994. The 
health outcome was based on the Nordic questionnaire, ``presence of any 
neck pain during the previous 12 months.'' Workplace exposure also 
relied on questionnaire data. Questions concerned work with hands over 
shoulder-level, static work positions, repetitive stereotypic 
movements, heavy lifting, sitting, standing, and high work pace. The 
authors note that the responders in 1994 were ``less inclined to have 
jobs that required them to spend a large amount of time with hands 
above shoulder level, jobs that required a large amount of standing, 
and jobs that required a large amount of heavy lifting.'' This 
admission, without providing further data, makes interpretation of 
results difficult. It is impossible to tell whether the study sample 
reflects the overall original sample population. By loss of those 
exposed to heavy lifting or working with hands above shoulder one 
cannot assess

[[<strong>Page</strong> 68448]]

whether this would have minor or major impact on the findings. Changes 
in job situations after 1990 were also not recorded, which would weaken 
association between job factors and neck pain. In responders without 
neck pain during the previous 12 months in 1990, the ``little influence 
on own work situation'' factor predicted neck pain during the previous 
12 months (odds ratio = 2.21; 95% confidence interval, 1.18 to 4.14) 
and previous 7 days in 1994 (OR = 2.85; 95% confidence interval, 1.21 
to 6.73) after adjustment for a series of potential confounders. 
Because of the serious questions with regard to changes in population 
exposure over time, OSHA believes the results are not interpretable and 
it was not included in Table V-1.

Biomechanical Evidence

    In a series of biomechanical and EMG studies, Harms-Ringdahl (1986, 
Ex. 26-1128) demonstrated that considerable stress is generated in the 
ligaments and joint capsule of the cervical spine with extreme neck 
flexion (more than 45 degrees). The extensor muscle activity is less 
than in the neutral position while the load moment (or torque) is 3-4 
times greater in extreme flexion.
    Many hand-intensive jobs and tasks require static neck contraction 
to permit accuracy in task performance. Thus, significant muscle stress 
and fatigue may occur with maintenance of static neck postures required 
in many office and assembly workplace settings (Hales and Bernard 1996, 
Ex. 26-896; Bernard and Fine 1997, Ex. 26-1; Onishi, Sakai, and Kogi 
1982, Ex. 26-991; Stock 1991, Ex. 26-1010; Westgaard and Bjorklund 
1987, Ex. 26-239). In confirmation of this postulate, several EMG 
studies have documented the increase in neck and upper back muscle 
activity from static work (Erdelyi et al.1988, Ex. 26-619; Onishi, 
Sakai, and Kogi 1982, Ex. 26-991; Schuldt et al.1987, Ex. 26-670). 
Hidalgo et al., 1992 (Ex. 26-631) reviewed the biomechanical literature 
of the neck and proposed that prolonged static contraction of neck 
muscles be limited to force levels at or below 1% of maximum voluntary 
contraction (MVC).
    It has also been shown that workplace interventions to mitigate 
static loading of neck muscles reduce pain, time out of work due to 
musculoskeletal problems, and EMG measured loading. Aaraas (1994a, Ex. 
26-892; 1994b, Ex. 26-62) evaluated users of video display terminals 
(VDTs) and assembly workers before and after ergonomic interventions 
consisting of changes in the workstations, tools, and work organization 
alterations. In assembly workers, mean static trapezius load decreased 
from 4.3% to 1.4% of MVC, and in VDT users, MVC declined from 2.7% to 
1.6%. This was accomplished with more accessible tool placement and 
support for elevated arms. The median duration for sick leave resulting 
from MSDs dropped from 23 to 2 days per person/year. As a result of 
interventions, including the reduction in trapezius loading, the VDT 
operators also reported less intensity and duration of pain in the neck 
and shoulder region. The study design did not permit the determination 
of which intervention(s) were responsible for the decline in MVC and 
sick leave, but it does support the role of workplace ergonomics.
    While epidemiologic studies regarding vibration and non-discogenic 
neck and shoulder pain have been inconclusive, there is some 
biomechanical evidence that vibration may affect muscle activity, and 
therefore could be pathogenic for neck disorders. This is a complex 
area, particularly since the most common shoulder diagnoses--
impingement and rotator cuff tendinitis--are clinically useful but 
without very specific pathophysiologic meaning. In the following review 
(Appendix I, Ex. 27-1), the neck, but not the shoulder, is shown to be 
associated with a vibration-related pathology. The separation of 
biomechanical, physiologically adaptive, and vibration-specific factors 
is especially difficult for the neck and shoulder. Scapular stability 
and posture are the heart of large-muscle activation sequences 
involving efficient distal muscle group movement (Mackinnon and Novak 
1997, Ex. 26-1309). Moreover, static shoulder posture, important for 
tool stabilization, is an important contributor to early arm fatigue 
(Sjogaard et al.1996, Ex. 26-213). Finally, the quality of a vibratory 
stimulus (continuous or discrete) has significant impacts on efferent 
recruitment and firing (Maeda et al.1996, Ex. 26-562). The combined 
effects of this complexity are not easily modeled. This is all the more 
reason why neck/shoulder symptoms should be carefully scrutinized when 
a power tool is part of the exposure background. It may prove difficult 
in practice to distinguish neck/shoulder symptoms that have their 
origins in strictly biomechanical processes from vibration-induced 
injuries. However, there is sufficient evidence in support of an 
etiology to merit intervention.
    As discussed earlier, skeletal muscle activity involves oxygen and 
energy consumption and metabolic end-product generation. Repeated 
damage from overuse without adequate recovery time for repair therefore 
has the potential to cause permanent structural damage to skeletal 
muscle (Armstrong et al.1993, Ex. 26-1110). Thus, work pacing can 
reasonably be expected to affect muscle function in the neck. Froberg 
et al.(1979, Ex. 26-117) compared female production workers performing 
piece work vs. salaried work. Piece work was associated with increased 
pain in the shoulders, arms, and back, accompanied by elevated 
excretion of adrenalin and noradrenalin.
    Unfortunately, financial incentives in piece workers may encourage 
workers to avoid pacing themselves in an effort to exceed production 
levels. Brisson et al.(1989, Ex. 26-937) postulated that the 
biomechanical stressors involved with piece work performed by female 
garment workers in Quebec, and the time pressures imposed by their 
piece work, combined to account for observed disability from MSDs. The 
association was related to the number of years performing piece work, 
and was independent of age, smoking, education, and total length of 
employment. In addition, some researchers suggest that workers may 
ignore early warning symptoms of work-related MSDs.

Conclusion

    The 1997 NIOSH report concluded the following with regard to 
physical work factors and MSDs of the neck/shoulder region:

    There is strong evidence that working groups with high levels of 
static contraction, prolonged static loads, or extreme postures 
involving the neck/shoulder muscles are at increased risk for neck/
shoulder MSDs. Consistently high ORs were found (twelve 
statistically significant studies with ORs over 3.0) providing 
evidence linking tension neck syndrome with static postures and 
static loads (Ex 26-1).

OSHA agrees with NIOSH with regard to the epidemiological evidence for 
an association between neck and neck/shoulder MSDs and physical risk 
factors related to forceful exertion, repetitive motion and awkward 
posture. Twelve out of thirteen well-conducted epidemiological 
investigations that directly observed or measured these factors in the 
workplace have found a significantly elevated risk of neck/shoulder 
MSDs in exposed workers verified by physical exam. This link between 
physical work factors and injury has been established across numerous 
job areas including VDT operation (Hunting 1981, Ex. 26-1276; 
electronics manufacture (Kilbom 1986, Ex. 500-41-75; Jonsson 1988, Ex. 
26-969) and fish processing (Nordander 1999, Ex 38-408). Several 
reviews have concluded that specific neck disorders, such as tension 
neck syndrome, are

[[<strong>Page</strong> 68449]]

consistently associated with repetitive work and prolonged static loads 
and postures of the neck (Hagberg et al.1995, Ex. 26-432; Kourinka and 
Forcier 1995, Ex 26-432; Grieco et al.1998, Ex. 26-627).
    The epidemiological evidence is supported by what is known about 
the biomechanics and pathogenesis of these neck disorders. It has been 
consistently shown by EMG that extreme postures and static loads on the 
neck/shoulder increase the internal force on the neck muscles Harms-
Ringdahl et al.1986, Ex. 26-136; Higado et al.1992, Ex. 26-631). 
Prolonged and frequent stress on these structures leads to muscle 
fatigue and reduced blood flow. The combination of high oxygen demand 
and low supply creates ischemia of the surrounding tissue and neck 
pain. Repeated episodes of stress does not allow adequate recovery time 
for repair raising the potential for long-term damage to the neck 
muscles (Armstrong 1993, Ex. 26-1110). OSHA concludes that a 
combination physical work-related factors, such as repeated movements 
of the upper arm and shoulder, static loads on the neck/shoulder, and 
extreme postures of the neck, are able to cause substantial and serious 
impairment to the neck and shoulder.

Muscoskeletal Disorders of the Shoulder

    Much of the evidence that relates physical work factors to shoulder 
disorders focuses on shoulder tendinitis. To understand how force, 
repetitive motion, and awkward postures lead to tendon injury one must 
understand tendon function and repair mechanisms. As muscles contract, 
tendons are subjected to mechanical loading and viscoelastic 
deformation. Tendons must have both tensile resistance to loading (to 
move attached bones) and elastic properties (to enable them to move 
around turns, as in the hand). When collagen bundles are placed under 
tension, they first elongate without significant increase in stress. 
With increased tension, they become stiffer in response to this further 
loading. If the load on these structures exceeds the elastic limit of 
the tissue (its ability to recoil to its original configuration), 
permanent changes occur (Ashton-Miller 1999, Ex. 26-414; Moore 1992a, 
Ex. 26-985; Chaffin and Andersson 1991, Ex. 26-420). During subsequent 
loading of the damaged tendon, less stiffness is observed. The ultimate 
strength of normal tendon and ligament is about 50% of that of cortical 
bone (Frankel and Nordin 1980, Ex. 26-1125), but structures that have 
exceeded the elastic limit fail at lower limits. In addition, if 
recovery time between contractions is too short, deformation can result 
in pathologic changes that decrease the tendon's ultimate strength 
(Thorson and Szabo 1992, Ex. 26-1171; Goldstein et al.1987, Ex. 26-
953). Tendon exhibits additional viscoelastic properties of relaxation 
and creep. That is, when a tendon is subjected to prolonged elongation 
and loading, the magnitude of the tensile force will gradually decrease 
(relaxation) and the length of the tendon will gradually increase 
(creep) to a level of equilibrium (Chaffin and Andersson 1991, Ex. 26-
420; Moore 1992a, Ex. 26-985; Woo et al.1994, Ex. 26-596). During 
repetitive loading, the tendon exhibits these properties and then 
recovers if there is sufficient recovery time. If the time interval 
between loadings does not permit restoration, then recovery can be 
incomplete, even if the elastic limit is not exceeded (Goldstein et 
al.1987, Ex. 26-953).
    Shoulder tendinitis includes supraspinatus and bicipital 
tendinitis. Bicipital tendinitis results when the tendon of the biceps 
brachii muscle rubs on the lesser tuberosity of the humerus bone, which 
occurs with motion of the shoulder (glenohumeral) joint during overhead 
arm movements. Persons affected with this disorder experience pain and 
tenderness in the shoulder area during shoulder flexion, elbow 
extension and forearm supination, or when the elbow and arm are 
extended and the forearm is supinated. Supraspinatus tendinitis is also 
known as rotator cuff disorder, subdeltoid tendinitis, subacromial 
tendinitis, or partial tear of the rotator cuff. Affected individuals 
commonly have pain in the front of the shoulder which is accentuated 
when they attempt to raise the arm away from the body (abduct the arm), 
although other movements may also be painful.
    There are multiple plausible theories for the pathogenesis of 
disorders of the rotator cuff. For purposes of this review, it is 
assumed that supraspinatus tendon tears and calcification represent 
endpoints of one pathological process as opposed to separate and unique 
endpoints. Mechanisms related to disorders of the rotator cuff complex 
with acute onset are excluded from this discussion (e.g., strains, 
falls, dislocations).
    The presence of a watershed or avascular zone in the supraspinatus 
tendon has been described and demonstrated by several investigators 
(Moseley and Goldie 1963, Ex. 26-306; Rothman and Parke 1965, Ex. 26-
499; Rathbun and Macnab 1970, Ex. 26-1376). It is believed that the 
avascular zone compromises the ability of the tenocytes within this 
portion of the tendon to repair damage to collagen fibers or their 
matrix. This impaired ability to repair the tendon implies that 
degenerative changes within this portion of the tendon will accumulate 
over time; therefore, the degree and progression of tendon degeneration 
will increase with increasing exposure to potential sources of injury, 
age, or both. Potential sources of injury to the tendon's collagen 
fibers or matrix may be ischemic, mechanical (impingement), or 
physiological (contractile load).
    According to the ischemia theory, the function and viability of the 
tenocytes within the supraspinatus tendon are compromised because they 
are in an avascular zone; therefore, they are unable to sustain the 
normal structure of the tendon over one's lifetime. This lack of 
maintenance manifests itself as degenerative changes within the 
substance of the tendon. The positive correlation between the 
prevalence of supraspinatus tendon degeneration and tears with age is 
consistent with this theory. It is not clear that task variables 
related to work are necessary in this pathogenetic model; however, 
Rothman and Macnab (1970, Ex. 26-499) postulated that shoulder 
adduction with neutral rotation would subject this avascular portion of 
the tendon to pressure from the humeral head, thus ``wringing out'' the 
blood from this already avascular area. If this were true, the duration 
of shoulder adduction is probably more important than the number of 
shoulder adductions.
    Neer (1972, Ex. 26-185) proposed that the subacromial bursa and 
supraspinatus tendon were mechanically impinged on the underside of the 
anterior aspect of the acromion process or coracoacromial ligament as 
the shoulder approached 80 degrees abduction or flexion when internally 
or externally rotated. Below 80 degrees flexion or abduction, the 
greater tuberosity of the humerus is generally not in immediate contact 
with the acromion process or the coracoacromial ligament. Beyond this 
degree of elevation, the humeral head is displaced down and away from 
the acromion and the ligament, thus relieving these structures of this 
contact stress. This contact stress is postulated to cause disruption 
of collagen fibers within the tendon mechanically. This mechanism of 
collagen disruption may (or may not) be combined with the phenomenon of 
impaired healing related to the avascular zone. The critical 
relationship between this proposed model of supraspinatus tendon 
disease and biomechanical task variables is the passage of the shoulder

[[<strong>Page</strong> 68450]]

through the 80 degrees abduction or flexion arc. Since this 
biomechanical stress occurs in a limited portion of these arcs, it is 
anticipated that the number of times the shoulder performs this task 
(per unit time) is more relevant than the duration of time the shoulder 
is in this position. Anatomical variations in the size and shape of the 
acromion (particularly type II [curved] and type III [hooked]) as well 
as hypertrophy of tissues related to the coracoacromial arch are also 
important factors. (Bigliani et al.1991, Ex. 26-603; Fu, Harner, and 
Klein 1991, Ex. 26-464).
    Posture plays an important role in rotator cuff tendinitis of the 
shoulder. Work with the arm elevated more than 60 degrees from the 
trunk is more stressful for the supraspinatus than work performed with 
the arm at the trunk. As the arm is raised or abducted the 
supraspinatus tendon becomes in contact with the undersurface of the 
acromion. They are in closest proximity between 60 and 120 degrees of 
arm elevation (Amadio 1995, as cited in Fine and Silverstein 1998, 
Ex.38-444). The precise pathosphysiology of rotator cuff tendinitis is 
not known. However, the role of overhead work, particularly of a static 
nature or very forceful exertions, is likely a crucial event (Andersson 
1995 and Levitz and Iannotti 1995, as cited in Fine and Silverstein, 
1998, Ex. 38-444). Impingement seems important. One suggested 
histologic pattern is a reversible inflammatory infiltrate, with 
increased vascularity and edema within the rotator cuff tendons, 
especially the supraspinatus tendon. This process, if it becomes 
chronic, has been postulated as leading to degenerative changes in the 
tendons. Eventually, enough degeneration occurs that a minor trauma 
causes or seems to cause a partial rotator cuff tear (Fine and 
Silverstein 1998, Ex. 38-444).
    Another shoulder disorder related to physical work factors is 
osteoarthritis of the acromioclavicular joint. Osteoarthritis refers to 
degenerative changes in the cervical spine that are apparent on 
radiological examination. A combination of high exposure to load 
lifting and high exposure to sports activities that engage the arm was 
a risk factor for shoulder tendinitis, as well as osteoarthritis of the 
acromioclavicular joint (Stenlund et al.1993, Ex. 26-1459). Kennedy, 
Hawkins, and Kristof (1978, Ex. 26-1135) found that 15% of competitive 
swimmers with repetitive overhead arm movements had significant 
shoulder disability, primarily due to impingement from executing 
butterfly and freestyle strokes.
    Physical work requires both mechanical and physiological responses, 
for example, muscle force and energy consumption. The mechanical 
responses include connective tissue deformation and yielding within the 
muscle; which increases intramuscular pressure. Increased intramuscular 
pressure in turn decreases blood flow through the muscle (Armstrong et 
al.1993, Ex. 26-1110).
    Nerves, vessels, and other soft tissues may be internally 
compressed under conditions of high-force exertions, awkward postures, 
static postures, and/or high velocity or acceleration of movement. For 
example, strong abduction or extension of the upper arm, as well as 
awkward postures of the neck, can compress parts of the brachioplexus 
under the scalene muscles and other anatomical structures. This 
compression can result in nerve and/or blood vessel damage or eventual 
damage to the tissues served by these nerves and vessels.
    Static postures, postures held over a period of time to resist the 
force of gravity or to stabilize a work piece--are particularly 
stressful to the musculoskeletal system. More precisely, static 
postures are usually defined as requiring isometric muscle force--
exertion without accompanying movement. Even with some movement, if the 
joint does not return to a neutral position and continual muscle force 
is required, the effect can be the same as a non-moving posture. Since 
blood vessels generally pass through the muscles they supply, static 
contraction of the muscle can reduce blood flow by as much as 90%. The 
consequent reduction in oxygen and nutrient supply and waste product 
clearance results in more rapid onset of fatigue and may predispose 
muscles and other tissues to injury. The increased intramuscular 
pressure exerted on neural tissue may result in chronic decrement in 
nerve function. The viscoelastic ligament and tendon tissues can 
exhibit ``creep'' over time, possibly reaching failure thresholds 
beyond which they are unable to regain resting length.
    Chronic reduction of blood flow may be a mechanism by which static 
muscle contractions lead to MSDs. Several studies have found that the 
small, slow motor units in patients with chronic muscle pain show 
changes consistent with reduced local oxygen concentrations (Larsson et 
al.1988, Ex. 26-1140; Dennett and Fry 1988, Ex. 26-104). Reduced blood 
flow and disruption of the transportation of nutrients and oxygen can 
produce intramuscular edema (Sjogaard 1988, Ex. 26-206). The effect can 
be compounded in situations where recovery time between static 
contractions is insufficient. Eventually, a number of changes can 
result: muscle membrane damage, abnormal calcium homeostasis, an 
increase in free radicals, a rise in other inflammatory mediators, and 
degenerative changes (Sjogaard and Sjogaard 1998, Ex. 26-1322).

Epidemiological Evidence

    In its review of the epidemiologic literature on work-related 
musculoskeletal disorders of the shoulder, NIOSH identified 38 
epidemiologic studies that examined workplace factors and their 
relationship to shoulder MSDs (Bernard 1997, Ex. 26-1). These studies 
examined the prevalence of shoulder disorders in workers exposed to 
repeated abduction extension or flexion of the shoulder in combination 
with strenuous work involving heavy loads or elevated arms. The MSDs 
were usually shoulder tendinitis or a collection of symptoms defined by 
stiffness, pain, and weakness. Table V-2 summarizes some key aspects of 
these investigations, such as the occupations examined, the 
biomechanical risk factors the workers were exposed to, whether 
exposures were directly observed or measured during the study, and 
whether the health outcomes were verified by trained medical personnel 
during physical examination. Sixteen of the studies relied on direct 
observation or measurements of exposure and verification of shoulder 
injury by physical exam. EMG of the forearm flexor muscles, frequency 
of shoulder movements, or angle of shoulder flexion were quantitatively 
measured in some of these studies. Another 24 studies relied either on 
job title information or questionnaire to obtain exposure information 
and/or used self-reported symptoms to define cases of shoulder MSDs. 
OSHA considers these investigations to be less reliable. All twelve 
studies with exposure and medical verification reported statistically 
significant associations between shoulder disorders and the physical 
work factors. The odds ratios reported in these studies ranged between 
1.6 and 46. The wide range in risks probably relates to differences in 
magnitude of exposure and case definition among the studies.

[[<strong>Page</strong> 68451]]



         Table V-2.--Summary of Epidemiology Studies Examining Musculoskeletal Disorders of the Shoulder
----------------------------------------------------------------------------------------------------------------
                                  Job type       Physical                       Physical     Risk measure  (95%
            Study                 studied         factors     Exposure basis      exam              CI) <SUP>1</SUP>
----------------------------------------------------------------------------------------------------------------
Hughes (1997) Ex. 26-907....  Aluminum         F/R?/P        Checklist......  Yes.........  OR=46 *
                               smelter.                                                     (3-550)
Herberts (1981) Ex. 26-51;    Shipyard         F/R?/P        Observation EMG  Yes.........  PRR=15-18 *
 (1984) Ex. 26-960.            welding.                                                     (14-22)
Bjelle (1979) Ex. 26-1112...  Industry case    F?/R/P        Observation....  Yes.........  OR=10.6 *
                               control.                                                     (2.3-54.9)
Frost (1999) Ex. 500-205-4..  Slaughter-house  F/R/P         Observation....  Yes.........  OR=5.3-7.9 *
                                                                                            (2.9-21.2)
Onishi (1976) Ex. 26-1222...  Multiple jobs..  F/R/P         Observation      Yes.........  OR=1.1-6.0 *
                                                              cycle time.                   (3.0-12.2)
Ohlsson (1995) Ex. 26-868...  Assembly line..  F?/R/P        Flexion cycle    Yes.........  OR=4.2 *
                                                              time.                         (1.4-13.2)
Baron (1991) Ex. 26-967.....  Grocery          F/R/P         Job titles.....  Yes.........  OR=3.9 *
                               checking.                                                    (1.4-11.0)
Ohlsson (1994) Ex. 26-1189..  Fish processing  F/R/P         Observation      Yes.........  OR=3.5 *
                                                              freq./angles.                 (1.6-7.2)
Nordander (1999) Ex. 38-408.  Fish processing  F?/R/P        Observation....  Yes.........  OR=3.5 *
                                                                                            (2.5-5.3)
Punnet (2000) Ex. 500-41-109  Auto workers     F/R/P         Cycle/           Yes.........  OR=1.1-4.0 *
                               case/control.                  flexionlift                   (1.7-9.4)
                                                              load.
Chiang (1993) Ex. 26-1117...  Fish processing  F/R/P?        Cycle time EMG.  Yes.........  OR=1.6-1.8 *
                                                                                            (1.2-2.5)
Kilbom (1987) Ex. 26-1277;    Electronics      F/R/P         MVC, flexion     Yes.........  NR *
 Jonsson (1988) Ex. 26-833.    manufacture.                   cycle time.
Bjelle (1981) Ex. 26-1519...  Industrial       F/R/P         Flexion EMG....  Yes.........  NR *
                               plant.
Sakakibara (1995) Ex. 26-800  Fruit bagging..  F?/R?/P       Observation arm  Yes.........  NR *
                                                              elevation.
Zetterberg (1997) Ex. 26-899  Auto assembly..  F/P           Cycle time tool  Yes.........  NR
                                                              weight.
English (1995) Ex. 26-848...  Patients case/   F/R/P         Question- naire  Yes.........  OR=2.3 *
                               control.                                                     (NR)
Andersen (1993) Ex. 26-1451.  Sewing machine.  F/R/P?        Job titles.....  No..........  OR=3.2 *
                                                                                            (1.7-7.4)
Andersen (1993) Ex. 26-1502.  Sewing machine.  F/R/P?        Job titles.....  Yes.........  NR *
Stenlund (1992) Ex. 26-733;   Rockblasting     V/F/R?        Questionaire...  Yes.........  OR=0.4-4.0 *
 (1993) Ex. 26-1459.           bricklaying.                                                 (1.8-9.2)
Wells (1983) Ex. 26-729.....  Letter carrier.  F/R?/P        Job title......  No..........  OR=5.7 *
                                                                                            (2.1-17.8)
Hoekstra (1994) Ex. 26-725..  Video terminal.  R/P           Observation....  No..........  OR=5.1*
                                                                                            (1.7-15.5)
Schibye (1995) Ex. 26-1463..  Sewing machine.  F?/R/P?       Questionaire...  No..........  NR
Burdorf (1991) Ex. 26-454...  Riveting.......  V             Tool             No..........  OR=1.5 *
                                                              aceleration.                  (NR)
Bergenudd (1988) Ex. 26-1342  Multiple         F/R?/P?       Questionnaire..  No..........  NR
                               industries.
Burt (1990) Ex. 26-698......  Computer entry.  R/P           Job title......  No..........  OR=2.6-4.1 *
                                                                                            (1.8-9.4)
Floodmark (1992) Ex. 26-1209  Vent shaft       F?/R?/P?      Job title......  No..........  OR=2.2 *
                               production.                                                  (1.4-4.4)
Hales (1989) Ex. DC-139-D...  Poultry          F/R           Job title......  Yes.........  OR=0.9-3.8 *
                               processing.                                                  (0.6-22.8)
Hales (1994) Ex. 26-131.....  Telecommunicati  R/P           Questionnaire..  Yes.........  NR
                               on.
Ignatius (1993) Ex. 26-1389.  Postal work....  F/R/P         Job title......  No..........  OR=1.8-2.2 *
                                                                                            (1.5-3.1)
Kiken (1990) Ex. 26-430.....  Poultry          F/R/P?        Job title......  Yes.........  OR=1.6-4.0
                               processing.                                                  (0.6-29)
Kvarnstrom (1983) Ex. 26-     Factory/office.  F/R/P?        Questionnaire..  Yes.........  RR=2.2-5.4
 1201.                                                                                      (NR)
McCormick (1990) Ex. 26-1334  Textile........  F/R/P?        Job title......  Yes.........  OR=1.1-1.3
                                                                                            (0.5-3.8)
Ohara (1976) Ex. 26-1.......  Cash register..  F?/R?/P?      Job title......  Yes.........  OR=1.7-2.2 *
                                                                                            (1.4-3.5)
Ohlsson (1989) Ex. 26-1290..  Auto assembly..  F/R/P?        Job title......  No..........  OR=2.0-3.4 *
                                                                                            (1.6-7.1)
Punnett (1985) Ex. 26-995...  Garment........  R/P?          Job title......  Yes.........  OR=2.2 *
                                                                                            (1.0-4.9)
Rossignol (1987) Ex. 26-804.  Computer         R/P           Questionnaire..  No..........  OR=2.5-4.8 *
                               operation.                                                   (1.6-17.2)
Sweeney (1994) Cited Ex. 26-  Sign language    R/P?          Questionnaire..  Yes.........  OR=2.5
 1.                            interpreter.                                                 (0.8-8.2)
De Zwart (1997) Ex. 26-617..  Various          F/R?/P?       Questionnaire..  No..........  OR=1.25-2.5 *
                               occupations.                                                 (p0.001)

[[<strong>Page</strong> 68452]]


LeMasters (1998) Ex. 500-121- Carpenters.....  F/R/P         Observation,     Only small    OR=2.3-3.2 * (1.1-
 44; Bhattacharya (1997) Ex.                                  measurement.     subset.       8.9)
 500-121-7; Booth-Jones
 (1998) Ex. 500-121-9.
Pope (1997) Ex. 32-137-1-4..  Various          F/R?/P        Questionnaire..  No..........  OR=2.1-5.5 *
                               occupations.                                                 (1.8-17.4)
Botha (1998) Ex. 500-121-10.  Nurses.........  F/R?/P        Questionnaire,   No..........  NR
                                                              observation.
De Joode (1997) Ex. 500-121-  Ship             F/R?/P        Strain gauge...  No..........  RI=1.7-3.9
 72.                           maintenance.                                                 (NR)
----------------------------------------------------------------------------------------------------------------
F=forceful exertions; R=repetitive motion; P=awkward posture; IR=incidence rate; OR=odds ratio; PRR=prevalence
  rate ratio; RI=risk index; NR=not reported; ?=presence of risk factor unclear.
* p0.05.
<SUP>1</SUP> 95% confidence interval expressed for the upper end of the risk measure range.

    The NIOSH noted several well-conducted studies that provided 
evidence of an exposure--response and temporal relationships. Chiang et 
al.(1993, Ex. 26-1117) divided 207 fish processing workers into three 
exposure groups based on EMG measurements of forearm flexor muscles and 
cycle time measurements of shoulder movements of representative job 
tasks. Exposure groups were: (1) Low force, low repetition (comparison 
group); (2) high force or high repetition; and (3) high force and high 
repetition. Shoulder girdle pain was the health outcome as defined by 
symptoms and palpable hardenings upon physical examination. The results 
showed a significant increasing trend in the prevalence of shoulder 
pain from group 1 (10 percent) to group 3 (50 percent).
    In another cross-sectional study, Ohlsson et al.(1995, Ex. 26-868) 
compared a group of 82 women who performed industrial assembly work 
requiring repetitive arm movements with static muscular work of the 
neck/shoulder with a referent group of unexposed women. The frequency, 
duration, and critical angles of movement were measured from videotape 
and observation. Shoulder MSDs such as tendinitis, acromicroclavicular 
syndrome, and frozen shoulder were determined from symptoms and 
physical exam. The risk of shoulder tendinitis in the exposed women was 
significantly greater than the unexposed women (OR=4.2; 95% CI 1.4-
13.2). The neck and shoulder disorders were also significantly (p0.05) 
associated with the number and duration of shoulder elevations greater 
than 60 degrees. The study of Bjelle et al.(1981, Ex. 26-1519) also 
found that the frequency of shoulder abduction and forward flexion past 
60 degrees was significantly greater (p0.05) for cases with neck/
shoulder disorders than for controls.
    In a prospective study design, Kilbom et al.(1986, Ex. 500-41-75; 
1987, Ex. 26-1277) assessed the health and exposure status of 06 
electronics manufacturing plant employees over a two year period. The 
employees were evaluated for maximum voluntary isometric contraction 
(MVC) of the forearm flexors and shoulder strength. Videotape was used 
to analyze cycle time and working postures and movements. Shoulder MSDs 
were determined annually based on interview and physical examination 
assessing tenderness on palpation as well as pain and restriction upon 
shoulder movement. Symptom severity was also scored. Logistic 
regression analysis showed significant relationship (p0.05) between 
MSDs and percentage of work cycle time with upper arm elevated. The 
number of elevations per hour was a strong predictor for increases in 
symptom severity over the study period. A follow-up investigation also 
found that the percent of the work cycle spent with the shoulder 
elevated was negatively associated with remaining symptom-free (Jonsson 
et al.1988, Ex. 26-833).
    NIOSH concluded that there was evidence for a positive association 
between highly repetitive work and shoulder MSDs. Only three studies 
specifically address the health outcome of shoulder tendinitis and 
these studies involve combined exposure to repetition with awkward 
shoulder postures or static shoulder loads. The other six studies with 
significant positive associations dealt primarily with symptoms. There 
was evidence for a relationship between repeated or sustained shoulder 
posture with greater than 60 degrees of flexion and abduction and 
shoulders MSDs. This holds for both shoulder tendinitis and nonspecific 
shoulder pain. NIOSH found insufficient evidence for a positive 
association between either force or vibration and shoulder MSDs because 
the studies that principally examined this risk factor relied on self-
reported questionnaires for assessment of exposure and health outcome.
    Twelve studies that address physical work factors and shoulder MSDs 
were submitted into the OSHA docket following publication of the 
proposal (Zetterberg et al.Ex. 26-899; De Zwart et al.1997, Ex. 500-
121-18; Punnett et al.2000, Ex. 500-41-109; LeMasters et al.Ex. 500-
121-9; Bhattacharya et al.1997, Ex. 500-121-7; Booth-Jones et al.1998; 
Ex. 500-121-44; Pope et al.1997, Ex. 500-71-42; Frost and Anderson 
1999, Ex. 500-41-57; Burdorf et al.1997, Ex. 500-71-24; Van Wendel de 
Joode 1997, Ex. 500-121-72; Botha and Bridger 1998, Ex. 500-121-10). 
Many of these studies showed that high physical loads in combination 
with elevated shoulder positions were associated with increased 
prevalence of shoulder disorders (Ex. 500-121-9; Ex. 500-121-7; Ex. 
500-121-44; Ex. 500-41-57; Ex. 500-41-109; Ex. 500-121-18; Ex. 500-121-
10; Ex. 500-121-72; Ex. 26-899). For example, Frost and Anderson (Ex. 
500-41-57) found a strong significant association (OR>5) among meat 
packers who worked extensively with arm elevation greater than 30 
degrees more than 10 times per minute and prevalence of rotor cuff 
tendinitis compared to those with no shoulder elevation. The risk 
increased with cumulative exposure years. Punnett et al.(Ex. 500-41-
109) reported a significant association between repeated shoulder 
abduction/flexion and shoulder disorders. There was evidence of 
exposure--response with frequency of shoulder movements to 90 degrees 
flexion or abduction. Shoulder

[[<strong>Page</strong> 68453]]

MSDs were confirmed by physical examination in both studies.

Biomechanical Evidence

    Rohmert (1973, Ex. 26-580) found that muscle contractions can be 
maintained for prolonged periods if kept below 20% of MVC. But other 
investigators (Westgaard and Aaras 1984, Ex. 26-1026) found chronic 
deleterious effects of contractions even if they are lower than 5% of 
MVC. This latter finding is supported by the observation that low-level 
static loading (such as shoulder loading in keyboard tasks) is 
associated with shoulder MSDs (Aaras et al.1998, Ex. 26-597). The 
supraspinatus muscle, a muscle severely constrained by bone and 
ligamentous tissue, demonstrates increased intramuscular pressure 
during small amounts of shoulder abduction or flexion (Jarvholm et 
al.1990, Ex. 26-285). Tichauer (1966, Ex. 26-1172) looked at the impact 
of arm posture on trapezius stress. He noted that arm abduction to 40 
degrees increased stress in the upper trapezius muscle eight times as 
much as when the arm was abducted to 20 degrees, and 64 times as much 
as at a 10 degrees. These study results suggests the possibility of 
chronic blood vessel and nerve compression during static tasks. Other 
laboratory evidence for muscle and tendon damage in these areas, as 
well as secondary compression of blood vessels and nerves, lends 
support to the connection between work-related static postural 
requirements and the development of these disorders.
    Biomechanical studies of shoulder posture show that muscle activity 
and subjective fatigue in the shoulder region increases as a function 
of shoulder elevation angle and load moment at the shoulder joint. 
There is also evidence of localized muscle fatigue based on a shift in 
the MPF of the EMG spectrum. Prolonged periods of neck flexion cause 
increased levels of discomfort and increased EMG activity in the neck 
extensor muscles.
    Herberts, Kadefors, and Broman (1980, Ex. 26-1129) measured EMG 
activity as a function of static shoulder posture in a laboratory study 
using 10 male subjects. The primary independent variable was posture. 
Subjects held a 2-kg load in the hand at waist, shoulder, and overhead 
heights using different combinations of flexion and abduction at the 
shoulder. EMG activity was measured using wire electrodes in the 
anterior and posterior portions of the deltoid, the supraspinatus, the 
infraspinatus, and the upper portion of the trapezius. Localized 
fatigue (a shift in EMG mean power frequency [MPF]) was observed in all 
muscle groups during shoulder-level and overhead work (p.05) during the 
1-minute trials. Even at waist level, fatigue was observed when the 
upper arm was abducted at an angle of 30 degrees.
    Hagberg (1981, Ex. 26-955) measured EMG activity and discomfort in 
the shoulder in a laboratory study of six female subjects. Surface 
electrodes recorded EMG activity in the descending trapezius, anterior 
deltoid, and biceps brachii while subjects performed repeated flexion 
of the shoulder every 4 seconds to an angle of 90 degrees for a period 
of 60 minutes. Heart rate and perceived exertion using Borg's scale was 
also recorded. Hand load was the independent variable: weights of 0.6 
kg, 1.6 kg, and 3.1 kg were held in the hand (in addition to a no-load 
treatment). Heart rate and perceived increased over the course of the 
trial. Heart rate and perceived were greater when a load was held in 
the hands. EMG activity in the trapezius was closely correlated with 
the external moment at the shoulder joint.
    Oberg, Sandsjo, and Kadefors (1994, Ex. 26-867) measured EMG 
activity and subjective discomfort in the shoulder-neck region in a 
laboratory study of 20 subjects (10 male, 10 female). Surface 
electrodes measured EMG activity in the right trapezius muscle while 
subjects abducted the arm to a 90 degree angle. Subjects reported 
fatigue using the Borg 10-point scale. Each subject was tested under 
two conditions: a 5-minute test with no load in the hand and a 2.5 
minute test with a 2-kg load in the hand. At the no-load level, there 
was no change in EMG MPF over the course of the trial; however, 
subjective fatigue increased. With the 2-kg. load, there was a small 
linear decrease in MPF over the trial and there was a negative 
correlation between MPF and the Borg rating <Register> = 0.46). The 
authors concluded that MPF was not a good proxy for perceived fatigue 
during low-intensity static exertions of the shoulder.
    Using EMG, several investigators have demonstrated that the 
supraspinatus muscle is activated throughout most of the range of 
motion of the shoulder. Herberts and Kadefors (1976, Ex. 26-470) and 
Herberts et al.(1984), Ex. 26-960 postulated that the level of tension 
in the supraspinatus muscle during arm elevation (with or without 
holding an object in the hands) was sufficiently high to increase 
intramuscular pressure to a point sufficient to compromise 
intramuscular circulation. As reported by Edwards, Hill, and McDonell 
(1999; Ex. 26-1232), intramuscular pressures of 20 mm Hg may be 
sufficient to prevent muscular perfusion. Since many of the blood 
vessels within the tendon are longitudinal extensions of the blood 
vessels in the muscle belly, reduced perfusion of the intramuscular 
blood vessels implies reduced perfusion of the intratendinous blood 
vessels. If this reduced perfusion is sustained for sufficient 
durations of time, the tenocytes or other tendon components are 
susceptible to ischemic injury. In terms of biomechanical task 
variables, experimental data suggest that overhead work may cause 
intramuscular pressures capable of reducing intramuscular perfusion. 
Lifting combined with arm elevation (shoulder load) also contributes to 
the magnitude of supraspinatus muscle activation. From a temporal 
perspective, this proposed model is more related to the duration of the 
intramuscular pressure than to its frequency.
    After reviewing the scientific literature, Winkel and Westgaard 
(1992a, Ex. 26-1163) recommended less than 4 hours of work requiring 
overhead or extended reach postures. For continuous work, they 
recommended exposure times of one hour or less, particularly if the 
work involved highly repetitive tasks, low worker control, or a lack of 
alternating tasks. When large forces are also exerted, they recommended 
that the exposure time should be even less.
    Wiker, Chaffin and Langolf (1999; Ex. 26-1028) used psychophysical 
methods to investigate the relationship between strength capacity of 
the shoulder complex and fatigue/discomfort induced by sustained 
awkward arm postures in simulated light assembly work. Awkward shoulder 
postures (arms above shoulder level) produced severe discomfort at less 
than 10% MVC within one hour and were unrelated to subject strength. 
These authors recommended elimination of overhead work even in light-
weight manual assembly environments, irrespective of individual worker 
strength or anthropometry.

Conclusion

    The 1997 NIOSH report made the following statement with regard to 
the epidemiological evidence that links physical work factors and 
shoulder tendinitis:

    The evidence for specific shoulder postures is strongest where 
there is combined exposure to several physical factors like holding 
a tool while overhead. The strength of the association was positive 
and consistent in six studies that used diagnosed cases of shoulder 
tendinitis or a combination of symptoms and physical findings 
consistent with tendinitis as the health outcome (Ex. 26-1).


[[<strong>Page</strong> 68454]]


OSHA agrees with NIOSH with regard to the epidemiological evidence for 
an association between shoulder tendinitis and a combination of 
physical risk factors related to sustained or repeated shoulder flexion 
and abduction, particularly when it includes an additional static hand 
load such as working overhead. Fifteen out of sixteen well-conducted 
epidemiological investigations that directly observed or measured these 
factors in the workplace have found a significantly elevated risk of 
shoulder MSDs in exposed workers verified by physical exam. This link 
between physical work factors and injury has been established across 
numerous job areas including assembly line work (Punnett et al.1998, 
Ex. 38-155; Ohlsson et. al. 1995, Ex. 26-868), electronics manufacture 
(Kilbom 1986, Ex. 500-41-75; Jonsson 1988, Ex. 26-969) and fish 
processing (Nordander et al.1999, Ex 38-408; Chiang et al.1993).
    The epidemiological evidence is supported by biomechanical studies 
and the pathogenesis of these shoulder disorders. It has been 
consistently shown by EMG that fatigue in the shoulder muscles occurs 
with abduction and flexion of the shoulder. Addition of a static load 
or requiring the arm/shoulder motion be performed repeatedly merely 
increases both muscle fatigue and perceived discomfort. Over time, 
these repeated actions stress the tendons in the shoulder causing 
gradual loss of elasticity and strength. Once the damage exceeds the 
reparative capacity of the tissue, ischemia sets in and the tendon 
becomes inflamed, resulting in a chronic tendinitis. The rotator cuff 
is particularly vulnerable to this pathology since muscles and tendons 
are already somewhat constrained by ligaments and bone. Severe postures 
can result in impingement of nerves and blood vessels further 
aggravating the injury. OSHA concludes that sustained or repeated 
exertions with the arms and shoulders in awkward postures, such as 
raised overhead, can increase the risk of substantial and serious 
impairment to the shoulder. During OSHA's hearing on it's proposal, a 
nurse who injured her back at work provided compelling testimony. 
Maggie Flannigan, a registered nurse with 19 years experience in 
various newborn ICUs (intensive care units) across the country told her 
story for inclusion in OSHA's rulemaking record. Ms. Flannigan reported 
having back, neck and shoulder pain for years while working and also 
after work. Then, while moving a 75-pound monitor down from, then back 
onto a five-foot high shelf, she sustained a severe injury to her upper 
back and shoulders. Ms. Flannigan said that other nurses had been 
injured doing similar tasks, but because

when people think of newborn ICU, they think of, okay, you've got a 
one-pound baby, so where are your stressors coming from? And they 
don't realize that we are responding to alarms in high places, that 
we're doing awkward postures and reaches, and we're pushing heavy 
equipment, and then sometimes we actually lift heavy equipment 
which, in my case, gave me a back injury.
    It took Ms. Flannigan eight months of treatment to recover and 
she is fearful of re-injury:
    I'm fearful of what's going to happen to me as I age. And I'm 
also fearful of losing my ability to work as a nurse. I love my 
profession. I wouldn't trade it. * * * Since I've been injured at 
work, my family really suffered. I couldn't bathe my children. I 
couldn't dress them, couldn't do the laundry. My five-year-old 
buckled my three-year-old in the car seat if I had to drive. He 
pushed the cart at the grocery store--my five-year-old pushed the 
shopping cart.
    Ms. Flannigan stated further :
    I know I'm not the first one hurt at my job, but what I can't 
live with is I won't be the last unless we start protecting American 
workers immediately with this ergonomic proposal so we can remove 
the ergonomic hazards or reduce them in the workplace. American 
workers deserve a place of employment free from recognized hazards 
because when a worker develops an MSD, it's not just a lost workday. 
It can be a life lost forever to pain and disability.

D. Disorders of the Upper Extremities

    This section summarizes the evidence that exposure to physical risk 
factors at work contribute to the pathogenesis of specific 
musculoskeletal disorders (MSDs) of the upper extremities. In this 
section, the upper extremities of interest are the elbow, forearm, 
wrist, and hand. The bulk of the evidence demonstrating a work-related 
risk center around five MSD classifications; these are epicondylitis, 
tendinitis of the hand and wrist, carpal tunnel syndrome, hand-arm 
vibration syndrome, and hypothenar hammer syndrome. There is an 
impressive body of data that address the role of three biomechanical 
risk factors in epicondylitis, tendinitis, and carpal tunnel syndrome. 
These risk factors are force exerted on the muscle, tendons, and 
nerves; repetitive motion involving the hands, wrists, and forearms; 
and awkward postures of the wrist and arm. Exposure to these factors 
often occurs concurrently in occupational settings and the evidence 
shows that the risk of injury is greatest when more than one factor is 
present. There are also studies that relate another biomechanical work 
factor, vibration from the use of hand-held power tools, to an 
increased risk of carpal tunnel syndrome and hand-arm vibration 
syndrome. Repeated impact or contact stress, as well as vibration, have 
been implicated in the development of hypothenar hammer syndrome. 
Contact stress can, itself, be viewed as a specific combination of 
repetitive motion and force applied directly to a localized area of 
tissue, in this case the palm.
    There are several types of evidence that continue to support force, 
repetition, awkward posture, and vibration as causative factors for 
MSDs of the upper extremities. Information on pathophysiology provides 
evidence that links exposure to risk factors to the physiological, 
anatomical, and pathological alterations in soft tissues of the upper 
extremities. This speaks to the biologic plausibility that work-related 
risk factors contribute to these injuries. There is voluminous 
epidemiological data that provide evidence of associations between 
worker exposure to the identified risk factors and the occurrence of 
upper extremity MSDs. Some of these studies recently have been reviewed 
by NIOSH (Bernard and Fine 1997, Ex. 26-1) and were discussed by OSHA 
in the Health Effects Appendicies to the proposed rule (Ex. 27-1). For 
the final rule, OSHA has evaluated many additional epidemiologic 
studies that were entered into the record by many rulemaking 
participants.
    Finally, there is biomechanical and psychophysical laboratory 
research that complement and corroborate the epidemiological evidence. 
These approaches are able to directly link exposure to ergonomic risk 
factors to biomechanical and subjective measurements of tissue response 
under a more controlled set of simulated work conditions. This evidence 
derives from studies reviewed in the Health Effects Appendices of the 
Proposed Rule (Ex. 27-1) and testimony of the many expert scientists 
that appeared at OSHA's rulemaking hearing. The evidence for each 
specific MSD covered in this section is discussed in the parts that 
follow.

Epicondylitis

    Epicondylitis is a form of tendinitis that affects the forearm 
extensor muscle-tendon units that extend from the hand and wrist to the 
epicondyle (elbow). The most common type is lateral epicondylitis 
(known as ``tennis elbow'') where the fibrous tissue at the bone-tendon 
junction (usually the extensor carpi radialis brevis muscle/tendon) on 
the outer elbow is inflamed. This is believed to be caused by repeated 
microrupture of the tendon from overuse of the muscles that control the

[[<strong>Page</strong> 68455]]

wrists and fingers. Clinical case reports have noted that patients with 
lateral epicondylitis were often in occupations that involved 
repetitive, forceful work, particularly repeated pronation and 
supination movements with the elbow fully extended. For example, in one 
case series it was reported that 48 percent of patients with lateral 
epicondylitis of unknown origin had occupations that involved gripping 
tools with consequent repetitive supination/pronation of the forearm 
(Sinclair 1965, Ex. 26-736). In a second smaller group of epicondylitis 
patients reported on in the same publication, 88 percent worked in jobs 
with constant gripping or repetitive movements.
    National surveillance data consistently show that the incidence of 
this injury is greatest in occupations requiring manually intensive 
demands on the upper extremities in a dynamic work environment, such as 
mechanics, butchers, and construction workers. This body of evidence 
provides ample biological plausibility to the notion that force, 
repetition, and awkward posture can contribute to this MSD. The 
interplay between pathophysiology and physical work factors is 
concisely summarized by Dr. Niklas Krause in his written testimony on 
the proposed ergonomic standard (Ex. 37-15).

    There always seems to be a mechanical overuse component in MSDs. 
Tissues react to mechanical stress or overuse or microtraumitization 
(whatever term is being used) with inflammation leading to edema, 
swelling, pain, and local repair mechanisms that lead to stiffness 
and reduced muscle elasticity (probably due to microadhesions of 
muscle and tendon sheets), inactivity, loss of strength, and, 
habitual guarding postures, which in turn set the stage for overuse, 
and so on, in increments. That is why we call these MSDs 
``cumulative trauma disorders''. My work on the pathogenesis of the 
tennis elbow measured the impact of these physiological changes, 
i.e., increased internal workload or muscle resistance due to 
reduced tissue elasticity leading to electromyographically 
detectable recruitment of ever more muscle fibers for the same 
amount of external workload (which was held constant in these 
electromyographic studies of isometric muscle action). This 
increased recruitment of more muscle fibers makes the patient more 
vulnerable to overexertion at even lower levels of external physical 
demands * * * until the patient is unable to even lift a cup. [Ex. 
37-15]

In a chapter of the Textbook of Clinical Occupational and Environmental 
Medicine (1994, Ex. 38-440), Dr. Martin Cherniak described the symptoms 
and disabling nature of epicondylitis:

    The characteristic symptoms are pain with lifting , gripping, 
and wrist extension.* * * Because grip and extension are so central 
to many jobs, lateral epicondylitis is a condition that can be 
irreconcilably chronic and produce major and undesirable changes in 
life and work, despite its seeming mundane nature. [Ex. 38-440, pp. 
384-385]

Epidemiological Evidence

    NIOSH reviewed 18 cross-sectional studies and one cohort study that 
addressed workplace risk factors and elbow MSDs. Table V-3 summarizes 
some key aspects of these investigations, such as the occupations 
examined, the biomechanical risk factors to which workers were exposed, 
whether exposures were directly observed or measured during the study, 
and whether the health outcomes were verified by trained medical 
personnel during physical examination. Most of the studies compared the 
prevalence of epicondylitis in workers with jobs known to have highly 
repetitive, forceful tasks (e.g. meat and fish processing) to those 
engaged in less repetitive, forceful work (e.g. office workers). In 
some cases, the work also involved awkward hand and wrist postures. In 
almost all the studies, workers were concurrently exposed to a 
combination of 2 or 3 factors. One study specifically examined 
vibration from the use of chain saws. Eleven of the studies based case 
definition on physical examination and worker exposure on observational 
analysis. Diagnosis of epicondylitis was consistent across studies and 
required the presence of pain on palpation of the epicondylar area and 
pain at the elbow upon resisted movement of the wrist. The existence of 
work-related risk factors was generally made based on job/task 
observation. Some studies videotaped job tasks and estimated cycle 
times, static loading on the forearm, and wrist posture in order to 
qualitatively group workers by exposure intensity. Other studies more 
subjectively evaluated risk factor exposure by job observation alone. 
Seven cross-sectional studies reviewed by NIOSH relied strictly on 
self-reports of symptoms or exposure; OSHA considers these 
investigations to be less reliable.

                       Table V-3.--Summary of Epidemiology Studies Examining Epicondylitis
----------------------------------------------------------------------------------------------------------------
                                  Job type       Physical                       Physical     Risk Measure  (95%
            Study                 studied         factors     Exposure basis      exam             CI) \1\
----------------------------------------------------------------------------------------------------------------
Hughes (1997) Ex. 26-907....  Aluminum         F/R?/P        Checklist......  Yes.........  OR=37*
                               smelter.                                                     (3-470)
Roquelaure (1996) Ex. 500-41- Manufacturing..  F/R/P         Checklist......  Yes.........  OR=7.7-18.0*
 111.                                                                                       (2.2-147)
Kurppa (1991) Ex. 26-53.....  Meat processing  F/R/P?        Observation....  Yes.........  IR=6.7*
                                                                                            (3.3-13.9)
Chiang (1993) Ex. 26-1117...  Fish processing  F/R/P?        Cycle time EMG.  Yes.........  OR=1.2-6.7*
                                                                                            (1.6-32.7)
Moore (1994) Ex. 26-1364....  Meat processing  F/R/P         Measurement....  Yes.........  OR=5.5*
                                                                                            (1.5-62)
Bovenzi (1991) Ex. 26-1433..  Forestry.......  V             Measurement....  Yes.........  OR=4.9*
                                                                                            (1.3-56)
SHARP (1993) Ex. 500-41-116.  Poultry          F/R/P?        Measurement....  Yes.........  NR*
                               processing.                                                  (p0.002)
Dimberg (1987) Ex. 26-945...  Automotive.....  F/R/P         Observation....  Yes.........  NR*
Dimberg (1989) Ex. 26-1211..  Automotive.....  F/R/P         Observation....  Yes.........  NR
Ritz (1995) Ex. 26-1473.....  Utilities......  F/R?/P?       Observation....  Yes.........  OR=1.2-1.7*
                                                                                            (1.0-2.7)
Luopajarvi (1979) Ex. 26-56.  Food production  F/R/P         Measurement....  Yes.........  OR=2.7
                                                                                            (0.7-15.9)
Baron (1991) Ex. 26-697.....  Grocery          F/R/P         Measurement....  Yes.........  OR=2.3
                               checking.                                                    (0.5-11)
Viikari-Juntura (1991) Ex.    Meat processing  F/R/P?        Observation....  Yes.........  OR=0.88
 26-1197.                                                                                   (0.3-2.8)

[[<strong>Page</strong> 68456]]


Roto (1984) Ex. 26-666......  Meat cutting...  F/R/P?        Job title......  Yes.........  OR=6.4*
                                                                                            (1.0-41)
Hoekstra (1994) Ex. 26-725..  Video terminal.  R/P           Observation....  No..........  OR=4.0*
                                                                                            (1.2-13)
Burt (1990) Ex. 26-698......  Computer entry.  R/P           Job title......  No..........  OR=2.8*) Ex. 26-1.4-
                                                                                             5.7)
Punnett (1985) Ex. 26-995...  Garment........  R/P?          Job title......  No..........  OR=2.4*
                                                                                            (1.2-4.2)
Ohlsson (1989) Ex. 26-1290..  Assembly line..  F?/R/P?       Job title......  No..........  OR=1.5-2.8
                                                                                            (0.8-10.7)
Andersen (1993) Ex. 26-1451.  Sewing machine.  F/R/P?        Observation....  No..........  OR=1.7
                                                                                            (0.9-3.3)
McCormack (1990) Ex. 26-1334  Textile........  F/R/P?        Job title......  Yes.........  OR=0.5-1.2
                                                                                            (0.5-3.4)
Bystrom (1995) Ex. 26-897...  Auto assembly..  F/R/P         Job title......  Yes.........  OR=0.7
                                                                                            (0.04-1.7)
----------------------------------------------------------------------------------------------------------------
F=forceful exertions; R=repetitive motion; P=awkward posture; ?=presence of risk factor unclear.
IR=incidence rate; OR=odds ratio; NR=not reported.
*=p0.05.
\1\ 95% confidence interval expressed for the upper end of the risk measure range.

    Seven of the 11 studies that relied on objective exposure 
assessments and medical confirmation of epicondylitis found 
statistically significant associations between exposure to work-related 
risk factors and risk of epicondylitis. The most reliable odds ratios 
(ORs) ranged between 1.0 to 5.5. Some studies deserve special mention. 
One study was able to divide fish processing workers into a low-force/
low-repetition group, a high-force or high-repetition group, and a 
high-force and high-repetition group based on observed cycle times and 
hand forces from electromyography (EMG) recordings of the forearm 
flexor muscles (Chiang et al.1993, Ex. 26-1117). An increasing trend 
was found in prevalence of epicondylitis with increased exposure 
intensity (not statistically significant). There was a significant 
difference between males in the highest exposed group and males in the 
lowest exposed group (OR=6.75; 95% CI 1.6-32.7), but this trend was not 
observed among female workers (OR=1.4; 95% CI 0.3-5.6). A prospective 
cohort study grouped meat processing workers into those engaged in 
strenuous (primarily cutters and packers) and non-strenuous work 
(primarily office work) based on repetitive and forceful tasks (Kurppa 
et al. 1991, Ex. 26-53). They reported a significantly increased 
incidence ratio (6.7; 95% CI 3.3-13.9) of epicondylitis among workers 
in strenuous jobs over the 31-month follow-up period. Because of the 
prospective study design, this study provided direct evidence of a 
temporal relationship between exposure to biomechanical risk factors 
and the increased incidence of epicondylitis.
    One study evaluated vibration as a risk factor for epicondylitis 
and reported a significantly greater prevalence of epicondylitis (OR = 
4.9; 95% CI 1.3-56) in forestry operators using chain saws compared to 
a comparison group of maintenance workers (Bovenzi et al.1991, Ex. 26-
1433).
    Evidence of exposure-response trends in the epicondylitis 
literature is limited because of the preponderance of studies that 
relied on dichotomous comparisons of exposed versus unexposed workers; 
however, one study found an increase (not statistically significant) in 
prevalence with the number of hours per week working as a grocery 
checker (Baron et al.1991, Ex. 26-697). Another reported a positive 
(not statistically significant) exposure-response relationship between 
duration of exposure to gas and waterworks jobs regarded as stressful 
to the elbow (Ritz 1995, Ex. 26-1473).
    Some unusually high ORs that were reported by a few studies and 
contained in the NIOSH (1997, Ex. 26-1) review may have been overstated 
due to bias. For example, one study of aluminum workers reported an OR 
of 37 between elbow/forearm disorders and the number of years of 
forearm twisting; however, the overall participation rate in the study 
was only 55 percent, leaving open the possibility of selection bias 
(Hughs and Silverstein 1997, Ex. 26-53). The cohort study by Kurppa et 
al.(1991, Ex. 26-53) reported an epicondylitis incidence rate (IR) of 
6.7 for workers performing strenuous tasks but counted recurrences in 
the same elbow as if they were new cases. Reanalysis by NIOSH placed 
the IR at 5.5 among workers with strenuous jobs versus those with non-
strenuous jobs after correcting for recurrent cases.
    A few studies reported ORs between 1-3 that were not statistically 
significant (Baron et al.1991, Ex. 26-697; Luopajarvi et al.1979, Ex. 
26-56). The low risk ratios reported in these studies may reflect the 
likelihood that the occupations studied (grocery checkers and assembly 
line food packers) were associated with relatively low forces directed 
to the forearm extensors combined with insufficient repetitiveness, as 
compared to other jobs that involve higher forces and more repetition, 
such as meat cutters/packers where higher prevalence rates of 
epicondylitis have been found (Moore and Garg 1994, Ex. 26-1364). In 
addition, cross-sectional studies are often subject to the ``healthy 
worker'' effect because of the exclusion of injured workers who may 
have left the workforce at the time a study was conducted. This can 
sometimes lead to an underestimation of prevalence.
    Most studies adequately controlled for the important confounder of 
age but the contribution of non-occupational injury to the elbow was 
often not addressed among groups of workers. The large number of 
studies reporting a positive association with exposure make it unlikely 
that non-occupational injuries were an important confounder. Dr. 
Cherniak emphasized the importance of work rather than non-work 
activities in the etiology of epicondylitis: ``Its popular epithet of 
tennis elbow notwithstanding, it is a common condition among industrial 
workers and

[[<strong>Page</strong> 68457]]

is not so common among players of racquet sports.'' [Ex. 38-440, p. 
384]
    NIOSH concluded that there was some evidence of an association 
between exposure to force and epicondylitis based on the existence of 
several studies with quantitative measures of load on the hand/forearm 
that showed strong ORs (>5) for this risk factor (Moore and Garg 1994, 
Ex. 26-1364; Chiang et al.1993, Ex. 26-1117). NIOSH concluded there was 
insufficient evidence of an association between epicondylitis and 
repetition or awkward posture alone based on an inadequate number of 
studies that examined these risk factors as the dominant exposure 
factor, particularly in any quantitative fashion. However, it is clear 
that, in many of the epidmiological studies of epicondylitis, 
repetition and, in some cases awkward posture, accompanied exposure to 
force (see Table V-3).
    Two additional epidemiological studies that address physical work 
factors and elbow disorders were submitted to the OSHA docket following 
publication of the proposal (Roquelaure et al.1996, Ex. 500-41-111; 
SHARP 1993, Ex. 500-41-116), which are summarized below and included in 
Table V-3. Both studies followed an adequate study design, directly 
observed or measured exposure to workers, and used physical exam to 
verify the MSD. OSHA, therefore, finds that the studies add 
substantially to the evidence that the combination of forceful 
exertion, repetitive motion, and awkward posture increase risk of 
injury to the elbow.
    The Safety and Health Assessment and Research Program (SHARP) of 
the Washington State Department of Labor and Industries (1993, Ex. 500-
41-116) conducted a cross-sectional study of 104 poultry processing 
workers. Epicondylitis was assessed by interview and physical 
examination. Exposure was assessed by a risk factor checklist that 
evaluated repetitiveness, forcefulness, mechanical stress, and wrist 
deviation. The study found the prevalence of upper extremity MSD by 
interview was 25% and by physical exam and interview was 17%. The 
number of repetitive exertions per hour was significantly predictive of 
epicondylitis (p=0.002).
    Roquelaure et al.(1996, Ex 500-41-111) reported that work 
characteristics of greater than 1 kg of hand force, less than 30-second 
cycle times, and static hand work in workers were associated with 
radial tunnel syndrome (RTS). RTS is a disorder in which the radial 
nerve becomes compressed near the elbow causing pain and tenderness, 
similar to epicondylitis. Roquelaure used a case-referent study of 21 
RTS cases and 21 controls while studying 2,250 television, shoe, and 
brake manufacturing workers. Participation rate was not reported. 
Referents were age-, gender-, and plant-matched workers selected at 
random from the same manufacturing population who had no upper limb 
disorder for the previous eight years. Exposure was determined by 
direct observation of two trained assessors using a checklist. RTS was 
determined by reviewing the past two years of medical files of the 
2,250 manufacturing workers. A case of RTS was defined as local 
tenderness 4-5 cm distal to lateral epicondyle, pain in forearm 
indirectly induced by supination, no peresis or muscle weakness and 
positive EMG and nerve conduction studies. For 1 kg or greater of hand 
force, an odds ratio of 18.0 (CI: 2.2-147.5, p=0.01) was reported 
compared to those cases exposed to less hand force. For workers with 
less than 30-second cycle times, an odds ratio of 8.7 (CI: 1.2-23.8, 
p=0.03) was reported compared to those who had longer cycle times. For 
workers with static hand work, an odds ratio of 7.7 (CI: 1.4-42.7, 
p=0.02) was reported compared to those involved in more dynamic work. 
This study demonstrates that an increased risk of RTS is associated 
with exposure to force, repetition and static posture of the hand.
    Two medical experts supplied written testimony on behalf of UPS 
indicating that epidemiological evidence to support an association 
between combined biomechanical factors (e.g. force, repetition, awkward 
posture) and the different types of tendinitis of the upper extremities 
(e.g. elbow (epicondylitis), hand/wrist (tenosynovitis)) likely are 
flawed because of imprecise case definition. Dr. Peter Nathan wrote:

    There is a startling lack of objective evidence to indicate that 
actual pathology is involved in many of the soft tissue discomfort 
complaints that are included under the umbrella of cumulative trauma 
disorders or musculoskeletal disorders--a primary focus of the 
ergonomic standard. * * * Dr. Armstrong refers to a Finnish study by 
Luopajarvi et al.(1979, Ex. 26-56) which is one of three valid 
studies referenced by Dr. Susan Stock in her 1991 meta-analysis of 
the literature relating work exposure to conditions of the neck and 
upper extremities. The variable representing tendinitis used by 
Luopajarvi and his colleagues was primarily symptoms confirmed by 
physical examination. This does not correspond to the classic 
medical definition of tendinitis, which requires objective evidence 
of true inflammation (Ex. 500-118).

Similarly, Dr. Nortin Hadler stated in written testimony:

    The health effect in this paper [Kurppa et. al. 1991, Ex. 26-53] 
is a sick leave consequent to regional disorders of the elbow or 
wrist/hand. The investigators devised their nosology to capture 
discomfort about the elbow and distal arm/hand. Essentially, all 
they are describing is localized soreness and/or tenderness. The 
criterion of swelling or crepitation and tenderness to palpation 
along the tendon and pain at the tendon sheath, in the peritendinous 
area, or the muscle/tendon junction during active movement of the 
tendon boils down to focal soreness/tenderness and nothing more 
specific or mysterious than that (Ex. 500-118).

These comments suggest that the two epidemiological studies cited above 
exclusively rely on a collection of subjective symptoms indicative of 
non-specific soreness and discomfort, rather than objective measurement 
of inflammation and tissue pathology. This criticism also applies to 
virtually all the existing epidemiological studies that examined 
epicondylitis since they used a similar set of criteria to diagnose 
this MSD. As a result, the commenters believe OSHA has not made a 
sufficient case that true epicondylitis (as well as tenosynovitis) is 
associated with workplace exposure to biomechanical risk factors.
    OSHA disagrees with the notion that evidence of tissue pathology 
among exposed workers is required to infer a causal relationship 
between exposure to physical risk factors in the workplace and 
epicondylitis. The studies of Luopajarvi et al.(Ex. 26-56) and Kurppa 
et al.(Ex. 26-53) were directed by the Institute of Occupational Health 
in Helsinki, Finland, which developed systematic methods for screening 
and diagnosing a number of occupational neck, shoulder, and upper limb 
disorders, including lateral and medial epicondylitis. The examination 
procedures and diagnostic criteria have been published in the peer-
reviewed literature (Waris et al.1979, Ex. 26-1218) and they were 
devised by a team of clinicians comprised of occupational physicians, 
an orthopedist, physiologist, and ergonomist. The diagnosis for lateral 
epicondylitis (the most common form of epicondylitis) is not simply 
self-reported elbow soreness. The tenderness must be localized over the 
lateral epicondyle and there must be pain associated with resisted 
extension of the wrist and fingers (resistence test). In the Finnish 
studies, these signs were evaluated by either physicians specializing 
in occupational health or a trained physiotherapist. Other potential 
causes unrelated to physical work factors, such as fractures, acute 
trauma, recreational injuries, infection, arthritis, pre-existing 
neurological diseases, etc., were assessed and screened out through

[[<strong>Page</strong> 68458]]

medical histories and personal interview.
    The Finnish criteria are consistent with procedures for the 
assessment, diagnosis, and management of elbow complaints recommended 
by the American College of Occupational and Environmental Medicine 
(ACOEM, Ex. 502-240). These guidelines do not call for tissue evidence 
of inflammation and pathology in diagnosing lateral epicondylitis, but 
rather depend on expert evaluation of unique signs and symptoms by a 
trained clinician upon physical examination. The food packers in the 
cross-sectional investigation by Luopajarvi et al. (Ex. 26-56) were 
examined by a physiotherapist specially trained at the Finnish 
Institute of Occupational Health. The meat processors in the 
prospective Kurppa et al.(Ex. 26-53) study were primarily diagnosed by 
occupational physicians at the plant using the criteria developed by 
the Finnish Institute. The same diagnostic approach was also used by 
the other key epidemiological studies that found an association between 
work-related factors and epicondylitis (Chiang et al.1993, Ex. 26-1117; 
Moore and Garg 1994, Ex. 26-1364; Bovenzi et al.1991, Ex. 26-1433). 
More specialized diagnostic tools, such as imaging and 
electromyography, are only advised if a prudent course of elbow/forearm 
rest and pain relief do not adequately correct the disorder or more 
serious complications are suspected (e.g. fracture, osteomyelitis, 
neurological damage).
    OSHA finds that the case definition of epicondylitis used by the 
epidemiological investigators is appropriate for diagnosing this MSD. 
The evaluations were administered by trained clinicians using specific 
and standardized criteria that are uniformly accepted by the medical 
community. This was confirmed by testimony from numerous physicians 
during the hearings (AFL-CIO, Ex. 500-218). The published clinical 
guidelines and testimony from the record cited above make clear that 
the criteria of localized tenderness at a critical bone-tendon junction 
(MSD symptom) combined with pain upon palpation and extension/flexion 
of the wrist during physical examination (positive physical finding) 
are sufficient for the proper diagnosis of epicondylitis without the 
need for further ``objective evidence of true inflammation.''

Biomechanical Evidence

    There is a very limited amount of specific study information 
available in the Health Effects Appendices for the proposed rule (Ex. 
27-1) that measure the biomechanical forces at the muscle-tendon units 
of the elbow. However, as discussed in the Health Effects Appendix, 
there is some evidence suggesting that tensile loading on the extensor 
carpi radialis brevis (ECRB) muscle created by muscular action in 
combination with elbow extension and pronation/supination of the 
forearm causes a compressive force at the tendon, ligament, and radial 
head of the elbow. Prolonged contact pressure and/or repeated loading 
is likely to produce fraying of the ECRB. The resulting cycle of 
damage/repair leads to clinical and pathological manifestations of 
lateral epicondylitis.

Conclusion

    The 1997 NIOSH report concluded the following with regard to the 
relationship between work-related physical risk factors and 
epicondylitis:

    There is strong evidence for a relationship between exposure to 
a combination of risk factors (e.g. force and repetition, force and 
posture) and epicondylitis. Based on a review of the epidemiologic 
studies, especially those with some quantitative evaluation of the 
risk factors, the evidence is clear that an exposure to a 
combination of exposures, especially at higher levels (as can be 
seen in, for example, meatpacking or construction work) increases 
the risk for epicondylitis (Ex. 26-1, Emphasis in original).

OSHA agrees with NIOSH that there is a reasonably strong body of 
evidence showing a relationship between exposure to combinations of 
biomechanical risk factors, usually forceful exertion/repetitive motion 
or forceful exertion/repetitive motion/awkward posture, and an 
increased risk of epicondylitis. This evidence emanates from the 
consistently positive associations in epidemiological studies of 
workers from several different industry sectors, especially those 
investigations that rely on expert verification of injury and objective 
determination of exposure. The epidemiological evidence is supported by 
the large number of clinical reports and investigations in the medical 
and sports literature. There is biological plausibility that exposure 
to combinations of risk factors can lead to epicondylitis since 
forceful and repetitive exertion of the forearm muscles and tendons are 
also consistent with the pathophysiology of epicondylitis. As described 
in the NIOSH review of the epidemiological evidence, there is less 
evidence that exposure to repetition or awkward posture alone, is 
associated with an increased risk of epicondylitis. OSHA concludes that 
workers who perform job tasks requiring repeated forceful movements, 
especially flexion, pronation, or supination with the arm extended, are 
at increased risk of developing epicondylitis.

Tendinitis of the Hand and Wrist

    Most cases of tendinitis of the hand and wrist originate as 
inflammation of the synovial sheath that provides protection for the 
tendons. This condition is known as tenosynovitis. Inflammation may 
occur in the flexor tendons on the palmar aspect of the wrist, extensor 
tendons on the back of the wrist, or the small separate collection of 
extensor tendons that controls the extension of the thumb. There are a 
number of pathophysiological outcomes that result from irritation of 
the tendons. If the sheath becomes aggravated, excessive synovial fluid 
can build up resulting in swelling along the affected tendon. Sometimes 
irritation can occur just proximal to the tendon sheath where there is 
no synovial fluid. This causes a dry rubbing of the tendon called 
peritendinitis crepitans, so named because of the discernable creaking 
sensation. There is also a type of tenosynovitis, known as stenosing 
tenovanginitis, caused by a constriction of the tendons at the mouth of 
the sheath. If this constriction occurs on the radial aspect of the 
wrist involving the extensor tendons to the thumb, it is known as De 
Quervain's syndrome. If the site of injury is the flexor tendons to the 
fingers, it is known as trigger finger. Stenosing tenovanginitis is 
thought to be the result of compression caused by the thickening of the 
retinaculum (band of ligaments around the wrist holding the tendons in 
place) leading to tendon entrapment.
    One publication in the record described the symptoms and prognosis 
of patients that have trigger finger or thumb:

    The classic picture [of trigger finger/thumb patients] is 
painful ``locking'' of the digit in flexion whereby the patient has 
difficulty extending the proximal interphalangeal joint. Extension 
can be accomplished passively using the other hand and produces a 
moderate amount of discomfort and a palpable painful ``snap.'' * * * 
The prognosis is excellent for a complete recovery barring the 
occurrence of multiple trigger fingers and/or significant 
osteoarthritis * * *. In these cases the course is usually 
prolonged. Patients tend to question their ability to return to 
their old jobs and, on occasion, any job. In general, workers should 
be able to return to heavy work, although it may take somewhat 
longer after surgery because of a tender palmar scar. [Ex. 38-453, 
pp. 105-106]


[[<strong>Page</strong> 68459]]



Epidemiological Evidence

    NIOSH (1997, Ex. 26-1) reviewed seven cross-sectional studies and 
one cohort study that addressed workplace risk factors and MSDs that 
specifically addressed hand/wrist tendinitis. Table V-4 summarizes some 
key aspects of these investigations. In these studies, tendinitis cases 
were identified primarily by physical examination, which usually 
included localized pain/tenderness at the tendons upon palpation during 
movement of the hand/wrist. However, diagnostic criteria varied across 
studies depending on the types of tenosynovitis of interest. For 
example, some investigations required the presence of swelling along 
the tendons of the wrist and/or signs of crepitation. In some cases, a 
positive Finkelstein's test was used to diagnose DeQuervain's syndrome. 
Because of the differences in case definition, it is difficult to 
compare prevalence rates from different studies, although measures of 
relative risk should be less affected as long as case definitions were 
non-differentially applied to exposed and unexposed groups (NIOSH 1997, 
Ex. 26-1).
    Exposure assessment was generally restricted to grouping workers in 
exposed and unexposed categories based on the existence of a 
combination of excessive force, repetitive motion, and awkward posture. 
In these studies, most exposed workers were subjected to the combined 
effect of at least two risk factors. Five studies relied on direct 
observation of job tasks and expert judgment to determine exposure 
(Armstrong et. al. 1987, Ex. 26-48; Luopajarvi et. al. 1979, Ex. 26-56; 
Bystrom et. al. 1995, Ex. 26-897; Kuorinka et. al. 1979, Ex. 26-639; 
Kurppa et. al. 1991, Ex. 26-53). One of these studies quantified force 
and repetitiveness for a subset of workers performing different jobs 
and grouped them according to these measurements (Armstrong et. al. 
1987, Ex. 26-48). Three studies used less reliable methods of assessing 
exposure such as self-reports or general knowledge of job tasks.

                   Table V-4.--Summary of Epidemiology Studies Examining Hand/Wrist Tendinitis
----------------------------------------------------------------------------------------------------------------
                                  Job type       Physical                       Physical     Risk measure  (95%
            Study                 studied         factors     Exposure basis      exam             CI)\1\
----------------------------------------------------------------------------------------------------------------
Kurppa (1991) Ex. 26-53.....  Meat processing  F/R/P?        Observation....  Yes.........  IR=14-38.5*
                                                                                            (11-56)
Armstrong (1987) Ex. 26-48..  Manufacturing..  F/R/P?        Measurement EMG  Yes.........  PRR=4.8-17*
                                                                                            (2.3-126)
Moore (2000) Ex. 500-71-41..  Pork processing  F/R?P         Observation....  Yes.........  PRR=7.0*
                               F/R?/P.
Luopajarvi (1979) Ex. 26-56.  Food production  F/R/P         Observation....  Yes.........  PRR=4.1*
                                                                                            (2.6-6.5)
Latko (1999) Ex. 38-123.....  Manufacturing..  R/F/P?        Measurement,     Yes.........  OR=3.2*
                                                              cycle time.                   (1.3-8.3)
Bystrom (1995) Ex. 26-897...  Auto assembly..  F/R/P         Forearm load,    Yes.........  PRR=2.5*
                                                              wrist flex.                   (1.0-6.2)
Kuorinka (1979) Ex. 26-639..  Scissor          F?/R/P        Cycle time,      Yes.........  PRR=1.4
                               production.                    wrist flex.                   (0.8-2.5)
Amano (1988) Cited in Ex. 26- Shoe assembly..  F?/R/P        Job title......  Yes.........  PRR=3.7-6.2*
 1.                                                                                         (2.7-14)
Roto (1984) Ex. 26-666......  Meat cutting...  F/R/P?        Job title......  Yes.........  PRR=3.1*
                                                                                            (1.4-6.7)
McCormack (1990) Ex. 26-1334  Textile........  F/R/P?        Job title......  Yes.........  PRR=0.4-3.0*
                                                                                            (1.4-6.4)
----------------------------------------------------------------------------------------------------------------
F=forceful exertions; R=repetitive motion; P=awkward posture; ?=presence of risk factor unclear.
IR=incidence rate; PRR=prevalence ratios;
*=p0.05.
\1\ 95% confidence interval expressed for the upper end of the risk measure range.

    Of the five studies with the most reliably documented exposure, 
four reported statistically significant increases in the prevalence of 
hand/wrist tendinitis in workers exposed to physical risk factors 
(Armstrong et al.1987, Ex. 26-48; Luopajarvi et al.1979, Ex. 26-56; 
Bystrom et al.1995, Ex. 26-897; Kurppa et al.1991, Ex.26-53). In their 
review, NIOSH (1997, Ex. 27-1) chose the prevalence ratio (PR) to 
represent an estimate of relative risk rather than the more commonly 
reported OR for hand/wrist tendinitis, because the OR can overestimate 
relative risk when prevalence rates among unexposed groups are high. A 
few of the studies on work-related tendinitis reported prevalence rates 
greater than 25 percent in exposed groups and greater than 10 percent 
in unexposed groups.
    The Armstrong et al.(Ex. 26-48) study was able to divide industrial 
workers at seven manufacturing plants into a low force/low repetition 
group, a high force/low repetition group, low force/high repetition 
group, and a high force/high repetition group based on EMG measurements 
and observed cycle times. They found exposure-related increases in the 
prevalence of tenosynovitis (including stenosing tenovanginitis). The 
high-force/low-repetition group and low-force/high-repetition group had 
PRs of 4.8 (95% CI 0.6-39.7) and 5.5 (95% CI 0.7-46.3), respectively, 
compared to the low-force/low-repetition group, while the high-force/
high-repetition group had a PR of 17.0 (2.3-126.2). The Kourinka et 
al.(Ex. 26-639) study of mostly female scissors makers found a non-
statistically significant increase in the prevalence of tenosynovitis 
(including peritendinitis) with an increase in the number of pieces 
handled per year. The PR was 1.4 (95% CI 0.8-2.5) among all exposed 
workers compared to a referent group of department store assistants. In 
this study, it is unclear whether cashiers (a potentially exposed 
group) were included in the referent population; if so, this would tend 
to diminish the association between exposure and outcome. The results 
of these two studies suggest the presence of a positive exposure-
response relationship between exposure to biomechanical risk

[[<strong>Page</strong> <strong>68460</strong>]]

factors and the risk of hand/wrist tendinitis.
    Luopajarvi et al.(Ex. 26-56) found a significant increase in PR 
(4.1; 95% CI 2.6-6.5) of tenosynovitis (including peritendinitis) among 
female assembly line food packers compared to department store 
assistants (cashiers excluded from the unexposed group). Bystrom et 
al.(Ex. 26-897) found a significant increase in PR (2.5; 95% CI 1.0-
6.2) of DeQuervain's syndrome among automobile assembly line workers 
compared to randomly selected subjects (adjusted for potential 
confounders) from the general population. The prospective cohort study 
by Kurppa et al.(Ex. 26-53) found a significant increase in the 
incidence of tenosynovitis (including peritendinitis and DeQuervain's 
syndrome) over a 31-month period in meat processing workers (primarily 
cutters and packers) engaged in strenuous compared to non-strenuous 
work (primarily office work). They reported relative risks ranging from 
14.0 to 38.5 for different job categories, but these may be 
overestimated since recurrences of tendinitis were counted as new cases 
and case ascertainment was different for the exposed and referent 
groups. This study does provide evidence of a temporal relationship 
between exposure to physical work factors and development of 
tendinitis. Confounders, such as gender and age, were adequately 
controlled for in the key studies.
    Two studies that address physical work factors and tenosynovitis 
were submitted to the OSHA docket following publication of the proposal 
(Moore 2000, Ex. 26-1364; Latko et al.1999, Ex. 38-123). Summary 
results of these studies also appear in Table V-4. Moore (Ex. 500-71-
41) found a significant increase in the prevalence of stenosing 
tenovanginitis as a result of jobs requiring repetitive and forceful 
use of hand tools compared to jobs without exposure to this risk 
factor. Latko et al.(Ex. 38-123) reported a significant linear trend 
between repetitive work and hand/wrist tendinitis (p0.01) in a cross-
sectional study of 438 manufacturing workers. Worker exposure to 
physical work factors were directly observed and measured in this study 
and tendinitis cases were confirmed through physical examination by an 
occupational physician in both the Moore and Latko studies.

Biomechanical Evidence

    Static and dynamic biomechanical models of the wrist have been used 
to estimate tensile, normal, and frictional forces in finger flexor 
tendons during static and dynamic work involving the hand (Exs. 26-582, 
38-418). Pinching and gripping activities produce tensile forces on the 
tendons that are three to four times the normal force on the fingers. 
Static biomechanical models predict that additional compressive and 
frictional forces are exerted on the tendon when the wrist deviates 
from a neutral position as the tendon sheaths slide against the bones 
of the carpal tunnel and flexor retinaculum. These predictions have 
been confirmed by cadaver studies of forces on the tendons, ligaments, 
and bones of the hand. A laboratory study showed that peak tensile 
forces in the flexor tendons were approximately doubled during a 
simulated caulking task with a straight wrist and approximately tripled 
during the same task with a flexed wrist (Moore et al.1991, Ex. 26-
183).
    When a dynamic component is added to the biomechanical model, it is 
predicted that tensile and normal forces on the finger flexor tendons 
increase rapidly during rapid wrist accelerations. These predictions 
are supported by a preliminary surveillance study that found wrist 
acceleration to be substantially higher in jobs with a high rate of 
upper extremity cumulative trauma disorders (Marras and Shoenmarklin 
1993, Ex. 26-172). The biomechanical and laboratory evidence provides 
additional support that biomechanical risk factors, such as sustained/
repetitive forceful exertions and flexion/extension of the wrist, can 
create internal strain on tendons that could result in injury 
consistent with tenosynovitis.

Conclusion

    The 1997 NIOSH report concluded the following with regard to the 
relationship between work-related physical risk factors and hand/wrist 
tendinitis: ``There is strong evidence that job tasks that require a 
combination of risk factors (e.g., highly repetitious, forceful hand/
wrist exertions) increase risk for hand/wrist tendinitis'' (Ex. 26-1). 
OSHA also finds clear epidemiologic evidence of a relationship between 
a combination of physical risk factors, such as repetitive and forceful 
hand activities with a flexed wrist, and tenosynovitis. This evidence 
is from the consistently positive associations in the epidemiological 
studies described above. There are also laboratory studies that confirm 
that hand-intensive work, particularly with a bent wrist, produces 
significant load and strain on the flexor tendons. The biomechanical 
evidence is consistent with the pathophysiology of tenosynovitis where 
sustained and elevated internal force on the tendon sheaths can be 
expected to cause synovial fluid accumulation, thickening of the 
sheath, tendon entrapment, and other physiological responses that lead 
to clinical symptoms associated with this MSD. These biomechanical 
studies demonstrate that the increased risk of hand/wrist tendinitis 
seen among workers exposed to forceful and repetitive hand activities 
is biologically plausible and consistent with the epidemiologic 
evidence. OSHA therefore concludes that workers exposed to these risk 
factors are at increased risk of developing hand/wrist tendinitis.

Carpal Tunnel Syndrome (CTS)

    CTS is a disorder that results from compression of the median nerve 
at the point of passage through the carpal tunnel, the narrow opening 
in the hand consisting of carpal bones of the wrist on the bottom and 
the carpal ligament on top. The carpal tunnel is a relatively ``tight'' 
compartment filled with flexor tendons as well as the median nerve that 
serve to move and enervate the fingers. Forceful contraction of the 
flexor tendons in the fingers that occur during repetitive hand tasks 
increase the pressure within the carpal tunnel (Ex. 38-444). Chronic 
intracarpal pressure limits the vascular flow to the median nerve and 
surrounding tissue leading to swelling of the tendon sheath. The 
epineural edema leads to compression of the median nerve against the 
carpal ligament. The ensuing loss of nerve function initially results 
in painful tingling and numbness in the hand. After several years, 
eventually the tendon tissue can become fibrotic and result in muscle 
weakness, reduced grip strength and loss of finger movement. CTS is 
often accompanied by tenosynovitis, which is not surprising given their 
common pathophysiology. CTS is a disabling condition that has 
frequently required surgery to provide the affected individual with 
relief. For example, in Washington State in 1996, more than one-third 
of all CTS workers' compensation claimants required surgery as part of 
their treatment (Ex. 500-71-47, P. 12). Histologic studies of flexor 
tendon sheaths sampled during carpal tunnel surgery support the above 
model since vascular changes consistent with ischemia and tissue edema 
are commonly observed (Ex. 26-838).
    National and international surveillance data have consistently 
indicated that the highest rates of CTS occur in occupations and job 
tasks (meat processing, assembly line work, intensive use of hand and 
power tools, etc.) requiring repeated wrist movements, forceful 
exertions, and


[[Continued on <strong>page</strong> 68461]]
</PRE>