IV. Overview of Rulemaking
A. History of Health Standards and Need to Revise PELs
One of the principal reasons, if not the single most important basis, for
Congress passing the Occupational Safety and Health Act of 1970 was Congress'
recognition of the need to protect workers from occupational health hazards.
In the preamble to the Act, Congress stated that one of the purposes was to
protect employees by "exploring ways to discover latent diseases,
establishing causal connections between diseases and work in environmental
conditions, and conduct other research relating to health problems, in
recognition of the fact that occupational health standards present problems
often different from those involved in occupational safety." (emphasis
The legislative history indicates Congressional concern for reduction in
health risk from both the recognized hazards and from the many newly utilized
chemicals. Congress stated in 1970:
In the field of occupational health the view is particularly bleak, and due
to the lack of information and records, may well be considerably worse than
we currently know. Occupational diseases which first commanded attention at
the beginning of the Industrial Revolution are still undermining the health
of workers. Substantial numbers, even today, fall victim to ancient
industrial poisons such as lead and mercury. Workers in the dusty trades
still contract various respiratory diseases. Other materials in industrial
use are only now being discovered to have toxic effects. In addition,
technological advances and new processes in American industry have brought
numerous new hazards to the workplace. Carcinogenic chemicals, lasers,
ultrasonic energy, beryllium metal, epoxy resins, pesticides, among others,
all present incipient threats to the health of workers. Indeed, new
materials and processes are being introduced into industry at a much faster
rate than the present meager resources of occupational health can keep up
with. It is estimated that every 20 minutes a new and potentially toxic
chemical is introduced into industry. New processes and new resources of
energy present occupational health problems of unprecedented complexity.
(Senate Report 91-1282, p.2).
To accomplish the goal of protecting workers from occupationally related
disease Congress created a three-pronged approach in the OSH Act.
First, Congress desired that OSHA, as soon as possible after it was
established, have in existence a set of basic, minimum health and safety
standards. To accomplish this it provided in Section 6(a) of the OSH Act
that OSHA should adopt within its first two years, without hearing or public
comment, established federal standards and national consensus standards.
At that time, under the Walsh-Healy Act, the Department of Labor had adopted
for government contractors approximately 400 health standards based on the
Threshold Limit Value (TLV) recommendations of the American Conference of
Governmental Industrial Hygienists (ACGIH). Those were adopted as
established federal standards. In addition about 25 exposure limits had been
recommended by the American Standards Association (presently called the
American National Standards Institute). Those were adopted as national
consensus standards. OSHA adopted these initial exposure limits in May,
1971. They are for the most part the maximum air contaminant levels set
forth in Tables Z-1, Z-2, and Z-3 of 29 CFR 1910.1000.
Congress recognized the need to update and add new standards. It created
two mechanisms for this purpose: regular or "6(b)" standards and emergency
or "6(c)" standards.
Congress specified the procedures for developing and promulgating regular
standards in Sections 6(b)(1)-(4) and 6(f). These sections provide that: the
public may petition for new standards; OSHA may set up an advisory committee
to assist in developing a standard; and, before issuing a standard, OSHA must
publish a proposal with an explanatory preamble, request public comments and
then publish an explanatory preamble with a final standard. In addition to
these general requirements of informal rulemaking, Congress specified that
OSHA must hold an oral hearing if requested and support its determination
with substantial evidence in the rulemaking record.
Congress also provided in Section 6(c) for the issuance of Emergency
Temporary Standards (ETS) to take immediate effect without rulemaking.
However, OSHA must then complete a Section 6(b) rulemaking within 6 months.
The criteria for issuing an ETS is that "employees are exposed to grave
danger from exposure to substances or agents determined to be toxic or
physically harmful or from new hazards, and that such emergency standard is
necessary to protect employees from that danger." OSHA has found that Sec.
6(c) procedures have not generally accelerated the regulatory process. Most
ETS's have been litigated and judicial stays have been issued either on
procedural or substantive grounds.
Since the passage of the Act in 1970, OSHA has made substantial progress in
improving the occupational health of workers for some priority health
hazards. Asbestos and arsenic exposures have been dramatically reduced,
substantially reducing cancer risk to employees. Lead exposures have been
reduced and we are now seeing a major reduction in employee blood lead
levels, and lead related diseases. Cotton dust exposures have been reduced
and byssinosis has been nearly eliminated from the textile work force. OSHA
has also substantially reduced significant health risk from some of the newer
chemicals such as ethylene oxide and vinyl chloride.
Through the hazard communication and access to employee exposure and medical
records standards, OSHA has greatly expanded the ability of employees to
learn about and protect themselves from health hazards.
OSHA's standards have proven to be feasible, often costing less than
estimated. The vinyl chloride standard cost one-tenth OSHA's contractor's
estimate. The cotton dust standard has been credited with improving the
industry's competitiveness and productivity by stimulating major technology
improvements while costing one-half OSHA's estimate.
The preambles to OSHA standards have been lengthy, detailed and
sophisticated. They have thoroughly analyzed health studies and
controversial scientific issues about carcinogenicity and risk assessment.
Extensive analyses of feasibility have been made.
OSHA has issued only 24 substance-specific health regulations since its
creation. It has not been able to review the many thousands of currently
unregulated chemicals in the workplace or to keep up with reviewing the
several thousand new chemicals introduced since its creation.
Using past approaches and practices, OSHA could continue to regulate a small
number of the high priority substances and those of greatest public interest.
However, it would take decades to review currently used chemicals and OSHA
would never be able to keep up with the many chemicals which will be
introduced in the future.
OSHA believes it is a major priority to update its existing PELs and to make
a substantial effort to control exposure to chemicals newly used in the
workplace for which no exposure limits exist. The existing health literature
and expert judgment indicate that such new or lower limits are needed to
protect against many types of deleterious health effects. These include
kidney and liver diseases, respiratory diseases, reductions in lung function,
nerve disorders and reduction in nerve function, carcinogenicity, irritation
to the eyes, throat, skin and other organs which prevent working safely, and
many other disorders and dysfunctions.
As the final regulatory analysis indicates, millions of employees are
exposed to levels of these chemicals which, the literature or expert opinion
indicates, do or may create deleterious health effects. Clearly, it is a
most important occupational health priority to reduce or eliminate such
disease and material impairments of health.
Congress clearly indicated that it was a major Congressional priority to
consider and control, when needed, the many thousands of unregulated
chemicals, and update the existing Z-Table chemicals. For example, the
previous quotation indicated Congress' concern with the thousands of newly
introduced chemicals. Congress also stated:
Accordingly, it is essential that such standards (Table Z chemicals) be
constantly improved and replaced as new knowledge and techniques are
developed. In addition there are occupational hazards, particularly those
affecting health - which are not covered by any standards at all. (Senate
Report 91-1282, p.6).
Government agencies and professional organizations have also recommended
that OSHA lower exposures for many Z-Table substances and add limits for
currently unregulated substances. The National Institute for Occupational
Safety and Health has recommended new or lower exposure limits for
approximately 190 chemicals (RELs) in its Recommendations for Occupational
Safety and Health Standards, Sept. 1986.
The American Conference of Governmental Industrial Hygienists (ACGIH)
1987-88 Threshold Limit Values (TLVs) adopted new exposure limits for more
than 160 substances not regulated by OSHA, and lower limits, short-term
exposure limits, ceiling limits or skin designations for more than 210
substances now regulated by OSHA.
In light of its priority to address the many unregulated health hazards and
improve the existing Z-Table limits, OSHA commenced a review process to
determine the best way to achieve this goal. It reviewed its past history
and set up an internal task force to consider the matter. In addition, OSHA
requested the Administrative Conference of the United States to study the
issue and make recommendations.
OSHA's analysis indicated a number of reasons why the standards development
process takes so long. These are discussed below. As can be seen some are
within OSHA's control and some are not.
OSHA, in the past, has determined which substances it would commence
standards development activity upon either through response to petitions or
internal reviews. The time and resources spent analyzing what should be done
next has been considerable.
An exhaustive review of the literature for each substance has been completed
prior to initiating rulemaking. Detailed presentations for each study and
lengthy discussions of every conceivable issue have been completed.
The lengthy preamble which has become a regular part of each standard is
largely the result of the need for OSHA to defend its standards in suits
brought inevitably by both industry and labor. See for example Synthetic
Organic Chemical Mfgs. v. Brennan; Oil Chemical and Atomic Workers v.
Brennan, 503 F. 2d 1155, 506 F. 2d 385 (3rd. Cir. 1974); Public Citizen,
Health Research Group et al v. Tyson; Association of Ethylene Oxide Users v.
Tyson, 796 F. 2d 1479 (D.C. Cir. 1986). OSHA feels more confident in the
successful defense of a standard if all possible issues have been
Individual standards have included a full range of ancillary provisions such
as monitoring, medical surveillance, action levels and work practices. This
increases the issues that must be studied and discussed, adding to the time
taken to complete a standard.
OSHA has performed technical and economic feasibility analyses as required
by statute. These have been made lengthier and more time consuming because a
range of possible alternative exposure limits have been explored.
The regulatory process is also longer and more resource intensive because of
analyses required either by statute or executive order. OSHA develops
Environmental Impact Statements as required by the National Environmental
Policy Act, conducts Regulatory Flexibility Analyses as required by the
Regulatory Flexibility Act and conducts detailed analyses required by the
Paperwork Reduction Act. All of the Presidents who have been in office
during OSHA's existence have stressed the need to reduce inflation and
improve the cost effectiveness of regulations. Under various Executive
Orders (E.O. 12044, 12291, etc.) OSHA has been required to perform extensive
OSHA has also followed more extensive and elaborate administrative
procedures than other health regulatory agencies. In addition to extensive
preambles to the proposed and final regulations, there is usually advance
notice of a proposal in the Federal Register. There is a complete
rulemaking docket into which the Agency places all the studies it relied
upon. In addition to public comment and an oral hearing as required by law,
opportunity is given for post hearing evidence and briefs. During the
hearing, questioning of witnesses, OSHA and its contractors is permitted.
Consequently OSHA has permitted the public more extensive procedural
opportunities than its statute, the Administrative Procedures Act, or legal
doctrine require. See the procedural rules in 29 CFR Part 1911. and
International Harvester v. Rucklehaus, 478 F. 2d 619 (D.C. Cir. 1973). These
procedures can increase agency knowledge and have been commended by the
courts. (See Industrial Union Dept. v. Hodgson 499 F. 2d 467 (D.C. Cir
1974). However, they do mean that if delays and continuances are granted at
each stage, the length of the rulemaking process is substantially extended.
OSHA in its first 17 years has also had to address difficult scientific
feasibility and policy issues. These include extrapolation from animal data
to humans (ETO supra), epidemiology, risk assessment and significant risk
analysis (Arsenic , 48 FR 1864, January 14, 1983; Asbestos, 51 FR 22612, June
20 1986), feasibility for industries with aging facilities (lead, arsenic,
supra), lowest feasible level (Benzene, 52 FR 34460, September 11, 1987, for
example and others). Naturally when considering such issues for the first
time, an Agency desires to go through extensive reviews before reaching final
OSHA consulted with the Administrative Conference of the United States
(ACUS) to determine what would be appropriate procedures to respond to the
issue of the large number of chemicals which need new exposure limits. The
Conference issued two lengthy reports of a study conducted by two professors
of administrative law. After extensive consideration, the ACUS made two sets
of recommendations to OSHA. Recommendation 87-1, 52 FR 23629 (1987) and
87-10, 52 FR 40147 (December 30, 1987).
The Administrative Conference specifically recommended:
1. Updating the 1971 Consensus Standards. The Occupational Safety and
Health Administration, as an interim step, should continue to update the
Table Z national consensus standards adopted in 1971 if updating can be
accomplished by expedited rulemaking procedure (e.g., including more concise
preambles) appropriate to the nature of the revised Table. OSHA should
update the 1971 standards on a generic basis (i.e., include multiple
standards in one proceeding) when consensus recommendations are available
which are generally accepted by employers and workers in the affected
industries, and when the new standards can be evaluated on the basis of risk
and feasibility information reasonably available to the Agency. This interim
step should not interfere with OSHA's continuing responsibility to promulgate
and modify safety and health standards.
As this discussion indicates, there is a clear and generally recognized need
to improve occupational health protection of workers from a substantial
number of chemicals which are present in the workplace. Clearly an improved
approach to regulation is needed to solve this problem in a reasonable time
period. OSHA's traditional approach, which has permitted on the average less
than two major health regulations per year, is not adequate to address the
backlog of at least 400 chemicals generally recognized as needing new or
lower exposure limits. OSHA has reviewed the law, Congressional intent, its
history, and the recommendations of experts. Based on this review, OSHA
adopted the approach described in Section IV-C which it has followed to
accomplish the crucial goal of improving occupational health protection of
workers. OSHA concluded that this approach has a greater health benefit and
will prevent more deaths and various deleterious health effects, than could
be achieved by allocating the same resources to comprehensive rulemaking for
a small group of substances.
B. Chronology of Regulation
The public process followed by OSHA to implement this rulemaking was started
on October 26, 1987, when the Department of Labor published its Semiannual
Agenda of Regulations at 52 FR 404494, 40534. The entry titled "Permissible
Exposure Limit Update" states OSHA would propose a wide scale updating of its
exposure limits. That entry scheduled March 1988 for the proposal and October
1988 for the final regulation. It also indicated that the American
Conference of Governmental Industrial Hygienists had updated many of its
recommended exposure limits (TLVs) since 1968. The 1968 TLVs were used as
the basis of most of OSHA's existing 6(a) exposure limits. A similar notice
was published in the next Semiannual Agenda on April 29, 1988, at 53 FR
OSHA published its proposal, "Air Contaminants, Proposed Rule" on June 7,
1988, at 53 FR 20960 (Ex. 2). That document filled 433 Federal
Register Pages. It considered whether exposure limits should be changed
for 428 substances. New or lower limits were proposed for 402 substances,
one was proposed to be raised and 25 were proposed to be unchanged.
That document included a 21 page discussion of the history, approach and
general issues. There followed 250 pages of health discussions which
included general discussions by type of effect (cardiovascular, kidney/liver,
etc.) and a concise individual discussion of the health effects associated
with exposure to each substance. The more important or controversial
substances had somewhat longer discussions than other substances. Each
individual substance discussion stated the health effects, summarized the
major relevant studies, and stated the reason OSHA preliminarily concluded
significant risk did or did not exist. Finally, the complete Preliminary
Regulatory Impact, Regulatory Flexibility and Feasibility Analysis was
printed running 71 pages along with one of the supplements on methodology.
(In this instance one Federal Register Page equaled approximately five
double-spaced typed pages.) OSHA placed in the public docket either before
June 7th, or shortly thereafter, all of the studies or documents upon which
it relied. This included Exs. 1-1 to 1-1208, which constitute virtually all
of the health studies upon which OSHA relied and that were discussed in the
preamble (a few minor or foreign studies referenced by ACGIH were not
available). Also included were many data bases on occupational health such as
the ACGIH documentation, NIOSH publications (for example NIOSH-TIC, Ex. 7, is
a 2500 page summary of health effects organized by chemical) and exposure
limits of other countries.
Also placed in the Docket were 6 supplements to the Regulatory Impact and
Feasibility Analysis (Exs. 4A-4F, approximately 1500 pages). Four volumes of
exposure, control technology and feasibility data organized by chemical were
placed in the record as Ex. 6 and a computer data tape for these volumes was
The June 7 Proposal scheduled July 1 for notices of intent to appear at the
hearing, July 8 for the submission of comments and testimony, and July 20 for
the hearing to begin. It suggested August 12 for post-hearing evidence and
August 26 for post-hearing briefs.
OSHA received several requests for extensions of time, some for quite
extended periods such as 9 months. On July 1 (53 FR 24956) (Ex. 5) OSHA
granted a brief extension. Comments and testimony were due July 25 and the
hearing was scheduled to commence July 28. August 19 and September 2 were
recommended respectively for post-hearing evidence and briefs.
In response to the proposal, OSHA received 1248 timely comments (Ex. 3-1 to
3-1248) and 204 late comments (Ex. L-3-1249 to L-3-1452). Approximately 800
of the comments and most of the late comments were very similar letters
generated by trade associations interested in the regulation of grain dust,
wood dust or styrene. The balance of comments ranged from short to 3000 page
submissions expressing views on the Proposal and including various studies.
OSHA also received 92 Notices of Intention to Appear (Exs. 8-1 to 8-92).
Approximately half of those included copies of testimony and substantive
evidence to be presented at the hearing. Established and published
procedures require that persons may testify for no longer than 10 minutes at
the hearing without submitting a notice.
The public comments, evidence and testimony totaled approximately 25,000
pages. This included actual comments and views, and attached health and
OSHA submitted to the docket in a timely fashion on July 25, 1988,
statements by the Director of Health Standards, the panel of economic
witnesses, and 7 other witnesses requested to testify by OSHA. NIOSH also
submitted on that date its comments, testimony and views.
In addition, for the convenience of the public, NIOSH placed in the record
the paper copy of all health studies on each substance in the rulemaking
organized by substance. This included the minor studies as well as the major
ones that OSHA had relied on and had already submitted to the record. This
submission was lengthy; however, all this information was indexed in the
NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) which is a 5
volume bibliography of occupational health studies which NIOSH is required by
statute to create and maintain. (Sec. 20(a)(6) of the OSH Act). The RTECS
have been available for many years. The vast majority of studies NIOSH
placed in the docket were publicly available either in major libraries or
from several computer data bases. Consequently they had all been readily
available to the public for many years. Participants testified that they
could be easily researched (Tr. August 4, Test. of Factor).
As OSHA had expected, a review of the comments and testimony indicates that
of 428 chemical in the rulemaking, approximately 280 received no comments or
testimony and OSHA preliminary conclusions on risk and feasibility were
reasonable and correct. Approximately 100 substances received only limited
mention by one or a few participants. Approximately 40 substances received
substantive comments but in some of these instances OSHA's proposed PEL was
not necessarily controversial. For example, the comments may have been
directed at technical improvements. Finally, approximately ten substances
received substantial comments and were deemed to be controversial. Because
of this filtering process, the rulemaking, as OSHA had anticipated, developed
a narrower and more manageable form.
Also, as had been OSHA's prior experience, major industry trade associations
were already formed, represented by major law firms, to express views on the
more controversial substances. For example, the Styrene Institute, which has
been in existence for 12 years, submitted about 2500 pages of comments,
studies and attachments (Ex. 3-742) and was represented by Keller & Heckman.
The Carbon Disulfide Committee, which has been in existence 11 years,
submitted approximately 1000 pages of comments and attachments (Ex. 3-747)
and was represented by Gibson, Dunn and Crutcher.
The Trade Unions also made major submissions on the chemicals they were
interested in. The Food and Allied Trades Department of the AFL-CIO
submitted extensive information on grain dust (Ex. 3-751). The Amalgamated
Clothing and Textile Workers Union submitted extensive information on
perchloroethylene (Ex. 43). The AFL-CIO (Ex. 39), United Autoworkers (Ex.
42), Workers' Institute of Safety and Health, United Paperworkers, Carpenters
and Woodworkers, and other unions also made major submissions.
The oral hearing commenced on July 28. It extended for 13 hearing days with
an average of approximately 7 hours of actual hearing time each day. The
total transcript was approximately 4000 pages. Approximately 200 witnesses
testified and responded to questions. Although there were some limits on
questioning by an individual participant, the questioning in total was
extensive since there often were more than 10 participants who questioned a
particular witness. It was evident that all participants had been able to
ask all the questions they wished by the end of the hearings. (Statement of
Administrative Law Judge, Tr. pp. 12-15 to 12-17, Aug. 12 1989).
The OSHA Staff panel responded to questions for three-quarters of one
hearing day. The OSHA economics panel responded to questions on three
separate occasions so that the public could complete questioning and have an
opportunity to ask questions after having reviewed all OSHA submissions. The
other OSHA witnesses fully responded to questions as did NIOSH (Tr. August
1). NIOSH agreed to return for further questions, but participants who
initially requested the right to ask further questions withdrew their
OSHA submitted to the Docket on July 25, 1988, approximately 40 site visit
reports and on August 8, 1988, approximately 40 more site visit reports were
submitted. The site visits were supplementary to the survey data and were
not the basis of OSHA's initial feasibility conclusions. The OSHA economics
panel returned on August 15, 1988, to answer questions specifically on those
OSHA's initial goal was to complete 100 site visits. However, the visits
needed employer approval both for the visit and the subsequent report before
the visit could be undertaken and/or the report submitted to the Docket.
Consequently OSHA could not completely control the completion of the site
visits or submission of the report to the Docket. OSHA completed several
additional site visits, but could not complete the related reports prior to
the end of the hearing. OSHA submitted those reports to the employer in
order to give the employer the option of putting them in the docket.
Employers in the steel industry and styrene users did submit several such
reports to the docket. Employers with grain exposures initially refused to
permit site visits. Although some later agreed to site visits, it was by
then too late to complete the visits and submit the reports to the record, so
the site visits were not made.
At the end of the hearing, the presiding officer indicated that, because of
the broad scope of the hearing, post-hearing evidence should be due 90 days
after the close of the hearing and post-hearing briefs 120 days after the
close of the hearing (Ex. 81). OSHA indicated both at the hearing and by
letters and telephone calls to participants that a shorter period was
required to maintain the schedule necessitated by the high priority of the
Proposal; OSHA stated that it did not think this would be unfair to
participants (Exs. 60-9, 81 A). By Federal Register notice of
September 7, 1988, (53 FR 34708; Ex. 100), the Secretary of Labor set October
7, 1988, for post-hearing evidence and October 31, 1988, for post-hearing
briefs. (This matter is discussed more fully in the Section III, Legal
Authority.) OSHA received 57 post-hearing submissions from public
participants totaling approximately 9000 pages. OSHA also received 41
post-hearing briefs. The total record includes substantially more than 4000
separate documents (individual studies, statements, comments, etc.).
The record was closed and certified by the presiding officer on November 10,
C. Details of Approach Used to Develop Regulation
The first step OSHA took to increase the pace of the regulatory process was
to make a determination not to analyze individual substances in order to
decide if they were of sufficient priority to be included in the project.
Rather OSHA reviewed existing data bases and lists of recommended exposure
limits, and determined which of these should be the starting point for the
OSHA concluded that the National Institute for Occupational Safety and
Health's (NIOSH) Recommended Exposure Limits (RELs) and the American
Conference of Governmental Industrial Hygienist's (ACGIH) 1987-88 Threshold
Limit Values (TLVs - a copyrighted term) provided the best two lists of
substances to be considered for regulation and to provide a starting point
for individual substance permissible exposure limits (PELs). See the
discussion at 53 FR 20966-7. These lists of substances are developed by
organizations of experts very knowledgeable both about the American work
place and the health literature. See the testimony of Mastromatteo (Ex. 22)
and NIOSH statement (Ex. 8-47). Both NIOSH and ACGIH publish documentation
to support their recommendations and permit outside participation in the
development of exposure limits.
Based on further analysis, the ACGIH TLVs were picked as the single best
list to define the substances to be included in this rulemaking. The details
of this OSHA analysis are provided in the Proposal (53 FR 20966-20967) and
will not be repeated here. OSHA's major reason was that the TLVs are more
extensive than the RELs and more generally used. There are over 600 TLVs and
approximately 160 RELs.
By using the ACGIH list of TLVs as the basis for the selection of substances
to be considered for this regulation, OSHA has greatly reduced the time it
would take to proceed with this rulemaking. The ACGIH's list is broad in
scope, attuned to the American workplace and developed by experts with
substantial health expertise. Therefore, OSHA concludes that this approach
to determining which substances will be considered for regulation is rational
and allows OSHA to expedite the process of improving the health of American
No changes to existing limits were considered in this rulemaking for
substances covered by limits established in substance-specific 6(b)
rulemaking (24 substances) or substances for which the process of 6(b)
rulemaking has already been initiated (9 substances). Since OSHA had already
begun the process of detailed analysis of these substances, additional review
was determined to be unduly repetitive and confusing at this point.
OSHA then compared the permissible exposure limits in Tables Z-1, Z-2, and
Z-3 to the TLV list. If the TLV and OSHA permissible exposure limits in the
Z-Tables were identical, the substance was not considered for change of PEL
in this proposal. The basis for this approach is that there is less
likelihood to be a need for a change in an exposure limit if an organization
which regularly reviews the literature has not changed its recommendation.
If the TLV and the PEL differed, the substance was considered for change of
PEL in this rulemaking. Also substances for which there was a TLV, but no
PEL, were included in this rulemaking. There is additional elaboration on
this methodology in Section IV. D., Boundaries to Regulation.
The second approach OSHA used to shorten the rulemaking process was to rely
to a greater extent than in the past on research and recommendations already
made by NIOSH and ACGIH as a starting point for OSHA's analysis.
Both organizations have experts undertake a complete review of the
literature for individual substances. Then they propose recommendations and
permit outside comments on their proposed recommendations. At the next
stage, each has a committee of experts again review the literature, as well
as the comments on the initially published recommendations before determining
the recommended exposure limit.
The approach OSHA followed was to first determine if the ACGIH-TLVs and
NIOSH RELs were similar. If they were, or if there was no NIOSH REL, then
OSHA reviewed the ACGIH documentation and recommendation. The ACGIH
documentation includes summaries and analyses of the major studies. If the
REL and TLV differed significantly, OSHA reviewed the studies and reasoning
upon which both NIOSH and ACGIH recommendations were based, and then chose
the recommendation which in OSHA's view was more appropriate.
In its review OSHA determined first whether the studies and analyses were
valid and of reasonable scientific quality. Second, it determined, based on
the studies, if the published documentation of the REL or TLV would meet
OSHA's legal requirements for setting a PEL. Thus, OSHA reviewed the studies
to see if there was substantial evidence of significant risk at the existing
PEL or, if there was no PEL, at exposures which might exist in the workplace
in the absence of any limit. Third, OSHA reviewed the studies to determine
if the new PEL would lead to substantial reduction in significant risk. If
this was so, and if the new PEL was feasible (see discussion below), OSHA
proposed the new PEL.
OSHA then divided the chemicals into 18 categories, generally by health
effect but, in a few instances, by other criteria. These categories
included cardiovascular, liver-kidney, respiratory and other types of
diseases or material health impairments. Each of these categories received
an individual literature review and discussion in the preamble analyzing the
etiology of substances which cause that health effect.
Some substances have several effects; the category chosen for each substance
was based on the health effect which most influenced the exposure level
proposed. However, OSHA individual discussions and conclusions referenced
and were based on all health effects associated with the specific substance.
Following each general discussion in the preamble, OSHA summarized the
documentation and provided references for each individual substance and
stated the reasons for the proposed new exposure limit. OSHA also stated the
reasons why it preliminarily concluded that the proposed new limit would
substantially reduce significant risk for that substance. In the case of 25
substances, OSHA explained why after review it did not propose a new exposure
limit. In one instance OSHA indicated the reasons for proposing to raise a
This method fully informed the public of the basis for OSHA's decisions.
The public was then in position to support or challenge OSHA's proposal, to
criticize the studies upon which OSHA relied, and to supply any additional
studies, evidence or views during the comment period, during the hearing or
as post hearing submissions.
OSHA is gratified by the degree of support for the proposal expressed by
rulemaking commenters. For example:
We believe this proposal is one of the most significant steps taken by OSHA
since its inception. The time and resources required for substance specific
rulemaking have greatly limited the number of PELs that OSHA has been able to
revise since they were adopted in 1971. Continuing individual rulemaking
would result in adding to the backlog of outdated PELs, while the method
chosen by OSHA for this revision assures that comprehensive update will be
completed within a reasonable time (Tr. August 2, Testimony of Tamarelli;
CMA supports the concept of revising the Z Table PELs in order to conform
with the threshold limit values, TLVs, that have been adopted or updated by
the American Conference of Governmental Industrial Hygienists...It is hard
for us to understand how anyone could say that the proceeding is too limited
in scope. To the contrary, a much more valid criticism might be that OSHA
has bitten off more than it can chew. The Agency quite reasonably has
concluded that adjusting the permissible exposure limits for chemicals on the
TLV list should be its first order of business (Tr. August 10, Testimony of
OSHA has taken a truly significant step in updating and enhancing the
regulatory provisions applicable to the workplace...OSHA was prudent in our
view to rely on the ACGIH TLVs to establish the bounds of the rulemaking (Tr.
August 9, Testimony of Holthouser/RMA).
GE strongly supports and endorses the Occupational Safety and Health
Administration's 6(b) rulemaking efforts to revise and upgrade the Z Tables
in 29 CFR 1910.1000 and encourages everyone concerned about employee health,
along with those involved in the rulemaking effort, to pursue a timely
conclusion to the process (Tr. August 9, Jones/GE).
The American Industrial Hygiene Association (AIHA), on the other hand, was
entirely in favor of OSHA's use of either an ACGIH or NIOSH limit, as the
AIHA supports the adoption by OSHA of NIOSH REL values as PELs on a
case-by-case basis where such values are supported by the scientific evidence
and are feasible from the standpoint of implementation (Ex. 8-16).
NIOSH expressed strong support for this rulemaking in general but submitted
specific comments on a number of substances that it believes should have
different limits from those proposed (Ex. 8-47). NIOSH's substance-specific
comments are addressed in connection with the preamble discussion of these
substances in Section VI.
Union representatives concurred with the need to update the Z-Tables. For
example, M. Seminario/ AFL-CIO stated: "We are pleased that OSHA and many
industry representatives have acknowledged finally that the current
permissible exposure limits do not protect workers, and we do indeed support
regulatory action to update the standards for toxic substances through the
use of broad-based rulemaking such as the Agency has proposed here. (Tr.
August 4, Testimony of Seminario/AFL-CIO).
However, Ms. Seminario did not agree with the approach that OSHA followed
stating that "it does not provide the workers with the kind of protection
that the OSHA Act requires." Union representatives stated that the proposed
standard was not adequate since it did not cover some substances of concern
and did not include the ancillary provisions which they felt were important.
OSHA does not agree with this judgment. It is impossible to cover all
substances, and OSHA has made a rational and reasonable judgment regarding
the bounds of this standard which is supported by most industry and
professional associations. OSHA is approaching the subject of ancillary
provisions through separate generic rulemakings which have already been
initiated. The basis of these judgments are discussed in detail in other
parts of this preamble.
OSHA stated in the proposal that it would consider all the additional views
and studies presented by participants. Based on what was best supported by
the entire record, OSHA would issue as the final standard either the PEL it
had proposed, make no change to the existing PEL, or issue a different PEL.
OSHA has followed this method of analysis in issuing the final rule.
OSHA's approach has indeed made it possible to increase the efficiency of
the regulatory process and issue new and revised PELs to protect the health
of workers from a large number of substances which were unregulated, or for
which existing exposure limits are out of date. It has also permitted OSHA
to rely on the best available scientific information and its past experience,
while giving the public both excellent notice and a full and fair opportunity
to comment, submit additional studies and make recommendations.
The improved efficiency of this rulemaking effort has not come from
sacrificing scientific validity. It has resulted from combining discussions
by health effect, concentrating on major issues and studies, using as a
starting point the research of expert organizations, and using public
comments to bring to attention additional relevant studies and issues. OSHA
has addressed in more detail those substances, issues and studies which have
been identified in the comments as the most controversial.
Third, OSHA has increased the efficiency of its feasibility analysis. Its
prior substance-by-substance, industry sector by industry sector,
process-by-process approach would have resulted in a vast body of duplicative
information in a multi-substance rulemaking. In addition, it would have made
it impossible to update very many substances in a reasonable period because
of the time and resources required.
OSHA followed several approaches to increase the efficiency of its
feasibility analysis process. First, it made maximum use of existing
information. OSHA's Integrated Management Information System (IMIS) is
probably the largest source of accurate exposure date in the world. It has
77,000 exposure measurements, is organized by industry and process, includes
judgments by compliance officers who are experts in industrial hygiene,
includes the number of workers represented by each measurement, and is
OSHA also used the two National Occupational Hazard Surveys (NOHS) by NIOSH.
These are good sources of the number of workers potentially exposed to
substances in each industry segment. OSHA also analyzed the large volume of
data in various publicly available data bases on control technology for
various substances, processes and industries. For the convenience of the
public, much of these data were combined into four volumes which were made
available to the public in the docket. OSHA also stated it would supply
these data on computer tape if requested.
OSHA had these data reviewed by approximately twenty experts in industrial
hygiene and industrial engineering. They made estimates of substances likely
to be used and processes likely to be present in each industry sector covered
by this regulation. These estimates were used as starting points. Much more
extensive information was gathered in a nationwide survey of 5700 firms.
These experts also made estimates of the cost to reduce exposure based on
scale of operation, type of process, and degree of exposure reduction needed.
Standard source materials such as industrial manuals were used. Many
processes are relatively standardized throughout industry and are used for a
variety of substances. For example, vat mixing takes place for many
substances in many industries. It can be uncontrolled without a cover and
involve manual loading of dry chemicals. It can be partially controlled with
covers and pump-loading of liquids. It can be fully controlled with
enclosure, ventilation and automated loading and unloading. Likely exposures
can be estimated by determining the amount of chemicals used and degree of
existing controls. Costs can be generalized throughout much of industry from
the size of the operation, estimated exposures, and the cost to go from one
degree of control to the improved level of control needed to achieve the
proposed reduction in exposures.
With this method of analysis, it is possible to make estimates of exposures,
controls necessary, exposure levels which can be achieved and costs from data
on substances and processes present and numbers of operations for each
industry segment. This information is sufficient for determining technical
feasibility and costs by industry segment. These data combined with publicly
available sales and profit ratio data make it possible to estimate economic
feasibility by industry segment.
To gather data on the substances present, types of processes, number of
processes, and controls in place by industry segment, OSHA commissioned the
largest survey it has ever conducted. Over 5700 questionnaires were
administered throughout the covered industry segment based on statistically
valid sampling techniques. A vast amount of information was received on
substances present, processes used and controls in place.
OSHA concludes that this approach is accurate on an industry sector by
industry sector basis for individual processes.
Overall, OSHA has a high degree of confidence that its estimates of
technical feasibility, costs and economic feasibility are accurate. OSHA has
had far more data available to it than it normally does in a single substance
rulemaking. The data were gathered systematically and were combined using a
methodology that was statistically valid and devised by persons with great
In addition, to increase the efficiency of the process, OSHA analyzed the
feasibility of the specific proposed exposure level for each substance rather
than considering a variety of different exposure levels.
To permit public comment on this approach and related data in an efficient
manner, OSHA published the entire Preliminary Regulatory Impact Analysis with
the Proposal in the Federal Register. In addition, it made available
to the public in the docket at the time of publication six supplements which
described in great detail the methodology and results of the survey by
OSHA concludes that it provided the public with all the information
participants would need to comment on, criticize or support OSHA's
feasibility conclusions. However, some participants requested more detailed
analysis of their sectors. Although OSHA indicated that it believed the data
it had made available were sufficient for these purposes, it did where
possible supply additional data and make special computer runs when requested
by the participants.
OSHA also stated it would consider all additional feasibility data submitted
by the public. Many participants did supply additional data. OSHA has
reviewed all data in the record in reaching its final feasibility
OSHA concludes that the approach it took developed good feasibility data,
permitted participants a reasonable opportunity to review OSHA's data and
supply their own, and was necessary to make the feasibility analysis process
The fourth difference in approach from single substance rulemaking was
OSHA's decision to limit this rulemaking to the issue of exposure limits.
OSHA has not considered medical surveillance, exposure monitoring, industrial
hygiene requirements and other ancillary provisions which were not included
in the existing 6(a) standard.
As stated in the Preamble, OSHA has concluded that the highest priority for
protecting occupational health is to lower exposure limits for many
substances where current knowledge indicates they are too high, or where
currently there are no limits but recent scientific knowledge indicates
limits are needed. This priority could not be achieved if ancillary
provisions were considered at the same time. As discussed in Section III,
Legal Authority, OSHA believes it is a rational use of its priority setting
power to consider ancillary provisions subsequently either in other generic
rulemakings or in substance specific Sec. 6(b) rulemakings. It has already
begun that process as discussed there. In any event, OSHA's approach
significantly improves occupational health protection.
A final method OSHA has followed to make this rulemaking more manageable is
to rely on its experience. OSHA has now made feasibility determinations for
several dozen substances and significant risk determinations approximately
one dozen times. Various issues regarding the analysis of data have been
reviewed many times. OSHA's approaches have been reviewed by the courts and
upheld or modified to meet judicial guidance. OSHA has not revisited all of
the issues in quite the depth it has given them in the past in light of its
experience. Of course, determinations and conclusions required by law have
been fully analyzed and supported. OSHA concludes it is both rational to rely
on its past experience and specifically permitted by Section 6(b)(5) of the
In the most important areas OSHA has not made any attempt to make the
regulatory process shorter. First, as discussed, it included individual
substance-by-substance health analyses and significant risk determinations.
Second, it has made feasibility determinations on the impact of the
regulation of all the substances for each industrial sector.
Third, OSHA has followed its traditional elaborate rulemaking process. Nine
months advance notice of the intent to issue a proposal was given. The
Proposal explained OSHA's reasoning at great length by citing and discussing
the evidence upon which OSHA relied. All the studies and analyses upon which
OSHA relied were made available in the docket. More than the minimum period
was allowed for comments.
Thirteen days were allowed for oral hearings. Testimony and evidence was
required to be submitted in advance and the testimony of OSHA, its economic
contractors and witnesses was made available in advance. Participants in the
hearings were permitted to question the OSHA panel, contractors, witnesses
and each other. Though the questioning permitted for each participant was
not unlimited, time was provided at the end to ensure that each participant
had completed all questioning he or she desired. As there were frequently
more than 10 participants who questioned a single witness, the total amount
of questioning was often extensive. The OSHA panel was questioned for
approximately four hours and the economics panel for more than six hours.
Various arrangements were made to bring back witnesses.
After the hearing, participants were allowed to file post-hearing evidence
to respond to comments and testimony, and to supply materials which they
could not submit by the deadline for comments. An additional period was
allowed for post-hearing briefs.
These are far more than the minimum procedural requirements of informal
rulemaking or hybrid rulemaking. Few if any agencies, for example, permit
questioning of the agency and its contractors. The process also effectively
permits participants a double round of comments.
The various time frames were shorter than some participants desired.
However, there was approximately one year between initial notice and final
opportunity for submissions and approximately five months from proposal to
post-hearing briefs. Not only is this far more than the legal minimum, but
it should have been ample to give sufficient time for participants to
effectively present their views and supporting evidence.
Adhering to a schedule is crucial for an agency to accomplish a high
priority, large scale project in a reasonable period of time. Among other
reasons for this is the fact that extra staff must be borrowed and contractor
assistance arranged. Both groups have other schedule commitments. If a
rulemaking is delayed too long these resources become lost to the project.
Consequently, medium length delays during the public participation period
become very lengthy delays of a final rule. As OSHA has pointed out, the
benefits of this standard to worker health are so significant that lengthy
delays of the final rule would result in a major loss in health protection.
Finally, OSHA has fully met the requirements pursuant to statute and
executive order to perform required analyses. OSHA has completed the
Regulatory Impact, Regulatory Flexibility and other analyses as required.
D. Boundaries to Regulation
The Proposal defined the substances covered by this rulemaking as a sub-set
of the substances listed in the 1987-88 Threshold Limit Values (TLV)
published by the American Conference of Governmental Industrial Hygienists
(ACGIH), (53 FR 20964-20966). OSHA pointed out in the Proposal that the TLV
listing had several advantages over other possible lists that might be used
for this purpose. Details of the OSHA analysis leading to this decision are
noted in the Proposal (53 FR 20966-20967). The primary considerations
leading to that OSHA decision were (1) number of substances covered by the
TLV listing; (2) available written documentation for the TLVs; (3) potential
employee exposures covered by TLVs; and (4) general acceptance of the TLVs by
OSHA realized that there are different valid approaches to the question of
identifying the boundaries for this type of rulemaking, and any decision must
balance completeness with practicality. Several commenters recommended that
the number of substances considered in this rulemaking be expanded to
include: (1) other lists; (2) the 160 substances in the existing Z-Tables
which were not discussed in the Proposal since their current TLVs were
identical with the existing OSHA PEL; and (3) substances which are in the
process of active (6b) rulemaking.
Relative to the first point, the additional lists suggested included the
following data bases: (a) Recommended Exposure Limits (REL) developed by the
National Institute for Occupational Safety and Health; (b) Workplace
Environmental Exposure Limits (WEEL's) developed by the American Industrial
Hygiene Association; (c) EPA's Integrated Risk Information System (IRIS); (d)
standards used by government agencies in the U.S.S.R. and other parts of
eastern and western Europe; and (e) internal company limits. The following
comments focus on this aspect: Ex. 8-47 (NIOSH), Ex. 43 (Frumin), Ex. 194
(AFL-CIO), Ex. 3-9 and Ex. 46 (Ziem), Ex. 42 C and 197 (UAW). Dr. Phillip J.
Landrigan suggested (TR August 1, Test. of Landrigan): (a) using a single
alternative listing instead of the TLVs; (b) combining several lists to
define the bounds of this rulemaking; or (c) adopting a smaller sub-set of
During the public hearing it was suggested that benefits would result from
developing PELs for additional substances. Specific substances suggested for
inclusion in this rulemaking included dimethylformamide (Ex. 47);
polychlorinated biphenyls (Tr 7-123); and glycol ethers (Ex. 3-639).
OSHA considered these constructive suggestions intended to expand the scope
of this rulemaking in an effort to improve the level of health protection
afforded workers. OSHA realizes that there are various approaches to this
type of rulemaking and believes that, while some of these suggestions have
merit, they introduce untenable problems at this stage of the rulemaking
process. OSHA has determined that it is preferable to consider some of these
suggestions as part of possible follow-on rulemaking based on the following
facts and analyses.
For many of the additional substances provided by these data bases there are
no quantitative exposure limits (e.g. IRIS and some NIOSH RELs). For other
substances it is not clear that the limits are actually applied to workplace
compliance situations (e.g. U.S.S.R. and eastern Europe limit). For others,
(internal corporate limits) an extended independent review procedure is not
defined. Use of a multiplicity of data bases to define the bounds for this
already large rulemaking would overwhelm the resources of OSHA and those
concerned parties who wish to comment on any proposed changes. This would
greatly delay prompt implementation of a regulation which is urgently needed
to protect the health of approximately 17 million workers who are potentially
exposed to the 428 substances for which revised PELs were considered in the
Proposal. Additional delay would be necessary since OSHA would be required
to publish a new Proposal for any substances not identified and discussed in
The record clearly shows that OSHA's decision to use the ACGIH TLVs as the
bounds for this effort was generally supported by most commenters for a
variety of reasons: Ex. 3-866 (ORC); Ex. 3-740 (ARCO); Ex. 3-741 and 196
(Dow); Ex. 170 (GE); Ex. 3-891 and 176 (SOCMA); Ex. 178 (API); Ex. 3-877 and
47 (RMA); Ex. 52 (HIMA) Ex. 3-678 and 58 (Abbott); Ex. 163 (Ergon Refining),
Ex. 186 (Halogenated Solvents Industry Alliance) and Ex. 165 (CMA). These
reasons include the general acceptance and probable feasibility of the TLVs,
and the need to have clearly defined limits for this rulemaking so it can be
concluded in a reasonable time period.
For example, Jeremiah Lynch speaking on behalf of CMA stated:
It is hard for us to understand how anyone could say the proceeding is too
limited in scope... The Agency quite reasonably has concluded that adjusting
the permissible exposure limits for chemicals on the TLV list should be its
first order of business. Further refinements in the regulation of these
chemicals can be dealt with at a later date, to the extent additional
requirements are found to be necessary. (Ex. 64).
It is necessary to limit the number of substances included in this
rulemaking so that it can be completed in a reasonable time frame. The total
number of chemicals in existence is well over 100,000. The 1985-86 edition
of the NIOSH Registry of Toxic Effects of Chemical Substances (RTECS; DHHS
(NIOSH) Publication No. 87-114) contains 88,693 prime chemical substances.
It is impossible to promulgate an OSHA regulation without limiting the number
of substances under consideration to manageable proportions. In this
regulation such limitations are based on several considerations including
the: (1) extent of use in commerce; (2) potential for exposure; and (3) lack
of any existing protective limits. The first two criteria are best satisfied
by using the well established TLVs as the data base for defining inclusion in
this rulemaking. Since the number of substances in the TLV listing would
still overwhelm the available resources, OSHA determined that it was
reasonable to defer for consideration at a later time those 160 substances
for which an OSHA PEL already exists and for which no change in TLV has
Such exclusion from consideration of change of PEL in this rulemaking does
not preclude OSHA from initiating 6(b) rulemaking in the future for any of
these substances or for any of the other substances covered by this
regulation. Because of this fact, OSHA believes that its initial decision
not to consider changing the PEL for those substances where the 1987-88 TLV
is identical with the existing OSHA PEL is appropriate.
OSHA also believes that it would unnecessarily complicate this rulemaking as
well as the individual rulemakings if changes to existing PELs were
considered at this time for the nine substances for the which the 6(b)
rulemaking process has already been started. The process of developing a 6(b)
standard for a single substance differs from the process used in this
proceeding since it involves consideration of various ancillary requirements
(exposure monitoring, medical surveillance, use of personal protective
equipment, labeling, etc.) which are not part of this rulemaking. Extensive
dockets have already been developed for the nine substances in this category
(Table IV-D-1). Since these 6(b) rulemakings should be completed in the near
future as tentatively scheduled by the Regulatory Agenda (52 FR 4044-40542),
it would unnecessarily complicate the rulemaking process without any
significant benefit if these nine substances were included in this
Until the new regulations for these nine substances are adopted, the
existing OSHA PELs will remain in effect as reflected in Table Z-1-A. This
same procedure is also used for the 160 substances where the existing PEL is
identical with the 1987-88 TLV, and for which new PELs are not proposed in
this rulemaking. These 160 substances were listed in Table VII-D of the
Proposal (53 FR 21254-21261).
It should be noted that no changes in PEL have been proposed for the 24
substances listed in Table VI-D-2 which are covered by individual 6(b)
regulations. The existing PELs for some of these substances are incorporated
into the Z-1-A Table both for reference purposes and because the individual
6(b) regulations for some of these substances do not cover all operations,
making maintenance of these PELs necessary to provide protection to workers
involved in these exempted activities (e.g. benzene, cotton dust, and
While the TLVs and RELs were used as a starting point for defining PELs, it
should be noted that OSHA made its own determination regarding each
individual limit. This was based on further evaluation of: (a) the TLV
Documentation and the Criteria Document supporting development of the REL;
(b) submissions to the public hearing record; and (c) information used in
developing some of the other data bases initially considered by OSHA in
developing the Proposal.
For a few substances, commenters suggested that it would be preferable to
delete a particular substance from this rulemaking and consider it as part of
a separate single substance rulemaking. Such comments were specifically
directed at wood dust (Ex. 3-748), grain dust (Ex. 3-752 and 3-755), sulfur
dioxide (Ex. 8-65), and styrene (Ex, 3-742).
In the case of wood dust and grain dust it is imperative that OSHA act
promptly since there is no existing accepted PEL for organic dusts. The
Occupational Safety and Health Review Commission has held that the standard
for nuisance dusts is not to be applicable to wood dust and grain dust. To
initiate and complete a 6(b) standard to control these substances would take
considerable time. Since there is a clear need for a PEL to protect against
the significant risk associated with exposures to wood dust and grain dust,
and there is now sufficient health and feasibility data to justify setting a
PEL, it is imperative that OSHA act promptly to protect workers exposed to
these hazardous substances. The analyses of these data are provided in the
discussion of these substances in Section VI. In the case of wood dust, the
Inter-Industry Wood Coordinating Committee indicated their concurrence
regarding adoption of a 5 mg/m(3) standard, which represents part of the
standard OSHA is proposing for wood dust. (Ex. 3-748 and 80).
In the case of sulfur dioxide, the commenter indicated that deletion was
appropriate due to the existence of a past record (Ex. 8-65 and Docket No.
H-039). OSHA agrees that the past public record must be considered, and has
incorporated the previous SO(2) record into the record for this rulemaking
(Ex. 10-45). OSHA has carefully considered all relevant information from the
previous SO(2) record in making its decision regarding a PEL for sulfur
dioxide, and the OSHA analysis of that record is included in the discussion
establishing the PEL for sulfur dioxide.
In the case of styrene, acrylamide, and a few other substances, questions
were raised regarding the adequacy of available information to develop a PEL
in this rulemaking. Questions were raised regarding definition of
carcinogenicity, feasibility (economic and technological), proper
classifications of health effects, and the proper PEL (Ex. 3-742 and 70). In
some instances, OSHA believes that sufficient information was not available
to reach a final determination regarding carcinogenicity. However,
information submitted by the commenters, together with material considered in
the development of the Proposal, was adequate to permit OSHA to reach a
conclusion regarding the PEL. The details of these analyses are included in
In some instances OSHA has specifically indicated that a specific revised
PEL may not fully eliminate significant risk of material impairment. In many
instances this is due to information and data limitations noted in the
discussion for that specific substance. However, the PEL is based on the
best current interpretation of data available at the time of promulgation of
the regulation. A PEL may change as more information becomes available, or
more accurate analytical procedures are developed. As an example, the PEL
for asbestos initially adopted in 1971 was revised in 1972. This level was
modified in 1976 and revised again in 1986.
After due consideration of all suggestions to delete substances from this
rulemaking, OSHA has determined that the only substance to be deleted from
this rulemaking is chromyl chloride for which a PEL was considered but not
adopted because OSHA had not given adequate notice in the Proposal. In the
case of three other substances (asphalt, fibrous glass and mineral wool), a
decision regarding a specific PEL is being delayed. OSHA has discussed the
reasons for adopting each PEL in Section VI of the preamble to this
As part of the public hearing submissions and presentations, several
individuals suggested expansion of the rulemaking to include provisions for
exposure monitoring and medical surveillance; Ex. 8-3 (Landrigan); Ex. 194
(AFL-CIO); Ex. 3-751 (Food & Allied Service Trades Dept.); (Ex. 42 and 197
(UAW); Ex. 43 (Frumin); Ex. 8-61 (Workers Institute); and 8-85 (Melius).
OSHA has adopted ancillary provisions for each substance regulated through
6(b) rulemaking. After 17 years, these provisions are included in only the 24
existing individual substance OSHA standards. OSHA finds that this rulemaking
is not the appropriate mechanism for extending the ancillary provisions to
all substances covered by the Z-Tables and agrees with the following comments
of PPG and Dow:
Further expansion of this rule to specifically impose additional regulatory
requirements such as medical surveillance, recordkeeping, personal protective
equipment, and training would unnecessarily complicate and confuse the main
objective of this proposed rule. There is also a greater likelihood of
challenge that has been an impediment to previous attempts to revise air
contaminant levels such as the Standards Completion Progress Project." Ex.
3-1158 (PPG) While we believe OSHA should not adopt medical surveillance and
exposure monitoring provisions in this rulemaking, we do believe OSHA should
promulgate generic medical surveillance and exposure monitoring standards in
a timely fashion. Ex. 169 (Dow)
On September 27, 1988, OSHA published Advance Notices of Proposal Rulemaking
(ANPRM) covering "Generic Standards for Exposure Monitoring (53 FR
32591-32595) and "Medical Surveillance Programs for Employees (53 FR
It was pointed out by Dr. I. Rosenthal, Rohm and Haas Co., that "if in the
future OSHA supplements up-to-date exposure standards with generic how-to
standards addressing medical surveillance, monitoring, personal protective
equipment and other similar items the Agency will have established over 400
defacto complete standards." (Ex. Tr. 3-17). OSHA therefore believes that
consideration of exposure monitoring and medical surveillance is best
achieved through the generic approach which has been initiated with the two
September 27, 1988, ANPRM's.
The legal and policy justification for limiting this rulemaking to
development of PELs is detailed in the Legal Authority Section of this
Preamble. The appropriateness of addressing PELs prior to considering
ancillary provisions was also endorsed on technical grounds by Dr. Marcus
Key, former Director of NIOSH (Ex.- TR 1-233, TR 1-265; TR 1-266).
Several commenters were concerned with the computational formula presently
noted in 1910.1000 (d)(2), for example, Ex. 3-742 (SIRC); Ex. 3-877 (RMA) and
Ex. 165 (CMA). These concerns relate to the lack of a requirement that this
formula should apply only to those situations in which an additive effect is
present. In contrast, the ACGIH discussion of the Threshold Limit Value for
Mixtures (TLV and BEI for 1988-89, p. 42) states that this equation is
applicable, "when two or more hazardous substances, which act upon the same
organ system, are present, their combined effect, rather than that of either
individually, should be given primary consideration." This reference goes on
to state that "exceptions to the above rule may be made when there is a good
reason to believe that the chief effects of the different harmful substances
are not in fact additive, but independent as when purely local effects on
different organs of the body are produced by the various components of the
The Proposal only redesignated paragraph 1910.1000 (d) as 1910.1000 (f) (53
FR 21263), a change which is no longer necessary. There was no intent to
reconsider or clarify this paragraph as part of this rulemaking. This subject
was not discussed in the Proposal and was not a topic for consideration as
part of this rulemaking. Therefore, it is not appropriate to consider any
changes to the mixture equation at this time.
During the Public Hearing a few commenters made specific suggestions
regarding other expansions to the subjects covered under this rulemaking.
(1) Expansion of the PELs to non-traditional work shifts (TR 3-231 3-234
(Arco)). OSHA is aware that work schedules in excess of 8 hrs/day are
becoming more common. However, it is clear that this rulemaking did not
provide an appropriate platform for full discussion of the technical problems
associated with adjusting PELs for work shifts other than an 8 hr/day. It
appears that such a question is highly substance specific depending on the
toxicology and body clearance mechanisms, and the significance of short term
exposure peaks. As such it may be more appropriate to provide guidance in
the form of an interpretation of acceptable alternate approaches to
extrapolating the 8 hr. PEL to other work shift periods. This might be
developed through the OSHA Industrial Hygiene Technical Manual or the Field
Operations Manual so it could be implemented on a case-by-case basis. OSHA
believes that this type of expansion of a Proposal intended to address only
PELs is not justified. The use of RELs developed using a 10 hr. definition
for developing 8 hr TWA PELs is supported by NIOSH testimony (Ex. 8-47) and
this approach has been used in this rulemaking.
(2) Representatives of the Workers Institute for Health and Safety
suggested incorporating surface contaminated limits, such as those
recommended by NIOSH and EPA for polychlorinated biphenyls (PCB) that are
used in the clean-up of the New Mexico State Highway Department Building (TR
7-123 and 7-124). Clearly this represents an exposure index which is
significantly different from "Air Contaminants" which is the subject of this
Proposal. OSHA therefore concludes that extension of this rulemaking to
include consideration of surface contamination limits is not appropriate.
(3) Mr. Richard Henderson representing the Chlorine Institute recommended
that, rather than reducing the PEL for mercury, OSHA maintain the existing
PEL and develop a comprehensive standard which includes a requirement for
periodic urinary mercury determination. The question of the appropriate PEL
for mercury is discussed in Section VI of this preamble. Regarding the
suggestion of urinary measurements which could be considered for many
substances other than mercury, OSHA finds that this represents an exposure
index which is significantly different from "Air Contaminants", the subject
of this rulemaking. OSHA concludes that extension of this rulemaking to
cover this subject is not appropriate.
In summary, OSHA has reviewed all comments to the record which might result
in changes to the boundaries of the rulemaking defined in the Proposal. OSHA
finds that the suggested additions and deletions would not be appropriate in
light of the objectives for this rulemaking established by OSHA and dictated
by the statutory requirements of the OSH Act.
Therefore, OSHA concluded that the 428 substances listed in Table I-E of the
Proposal (53 FR 20968-20976) should be considered for change in the PEL as
part of this regulation. These substances are listed in the Index-Locator
Section (II) of this preamble.
The Z-1-A Table in this regulation also incorporates the existing PELs for:
(1) the 160 substances from the existing Z-Tables, which were not considered
for changes in the PEL; (2) 9 substances for which 6(b) rulemaking is in
progress; and (3) some of the 24 substances covered by individual OSHA
standards where some sectors are not covered by the individual substance
The Z-1-A Table lists all substances covered by this regulation, whether or
not the PEL has been changed, whether or not a 6(b) standard has been
undertaken on a specific substance, and whether or not a 6(b) standard covers
the substance either fully or partially. In the case of substances regulated
by individual substance OSHA standards, the Z-1-A Table cross references the
Table IV-D-1 Substances for which OSHA Has Initiated 6(b) Rulemaking.
Cadmium Dust and Fume
Methyl Cellosolve Acetate
Table IV-D-2. Substances Regulated by OSHA Under Section 6(b).
CHEMICAL NAME STANDARD
Arsenic (Inorganic) 1910.1018
Bis-Chloromethyl Ether 1910.1008
Coke Oven Emissions 1910.1029
Cotton Dust 1910.1043
Ethylene Oxide 1910.1047
Methyl Chloromethyl Ether 1910.1006
Vinyl Chloride 1910.1017
E. Special Considerations
In the Proposal several substances were identified (53 FR 20978, Tables
I-F-A, I-F-B, I-F-C and I-F-D) as requiring special attention. This was due
to the presence of "significant differences" between the exposure limits
recommended by the various data bases initially considered in this
rulemaking. This same Section of the Proposal also identified some basic
assumptions used to initially simplify the definition of "significant
difference." The objective of this effort was to encourage comments during
the Public Hearing process for those substances where there was greater
potential for uncertainly regarding the proposed PEL.
Comments were received on some of these substances. NIOSH (Ex.8-47)
commented on all those substances for which a REL existed, as well as for
many other substances noted in these four Tables. Extensive comments were
submitted regarding the proposed PELs for Acetone (Ex. 8-54, 3-69, 3-661,
3-741, Tr. VI pp. 89-247); Acrylamide (Ex. 3-961); Carbon disulfide (Ex.
8-19, 8-45, 3-659, 3-674, 3-897, 3-945, 3-1158, 3-753); and Sulfur dioxide
(Ex. 3-1123, 8-22, 8-57, 8-65, 3-349, 8-9). A considerable number of
comments were also directed at the selection of RELs (SOCMA, Exs. 3-891 and
176; Dow Chemical, Ex. 3-741; Rubber Manufacturers, Ex. 3-877). For example,
GE (Ex. 170) stated:
It is apparent from the testimony given during the hearings and comments
submitted into the rulemaking record that the Recommended Exposure Limits
(RELs) are a source of considerable controversy...a wide cross-section of
occupational health professionals from industry, government and academia
believe there are substantial flaws in the contract process under which NIOSH
RELs were developed, including limitations in peer reviews, feasibility
considerations, and the methodologies employed in extrapolating animal
toxicological data and limited epidemiology findings to workplace exposure
limits. (Ex. 170)
NIOSH pointed out that "Each Criteria Document is reviewed by experts
representing affected industries, organized labor, and trade or professional
organizations, and by scientists, physicians, and other health professionals
with related experience in academia, government, or industry. The number of
these external peer reviewers normally is greater than 10 and often exceeds
twice that number. In addition to the invaluable contribution their comments
make to the completed Criteria Document, OSHA receives, along with the
completed Criteria Document, the full text of each reviewer's written
comments accompanied by itemized annotations indicating how the draft was
modified in response, or providing the rationale if the comment or
recommendation was not adopted. Each Criteria Document contains an extensive
summary in which the basis for the Recommended Exposure Limit (REL) is
carefully developed with clear and explicit citation of the data relied upon
at all steps of the logical development. No other source of exposure limits
approximates the comprehensiveness of these documents." OSHA believes that
its use of the RELs in this rulemaking is appropriate.
These submissions achieved the OSHA objectives of stimulating the input of
new data, analyses, and information to assist OSHA in this rulemaking based
on the full record for each individual substance. The discussion and
application of this information to set specific PELs is included in the
individual substances discussions in Section VI of this Preamble.
While OSHA did initially identify basic assumptions regarding significant
differences (53 FR 20977), the final OSHA decision regarding selection of a
specific PEL is based on a case-by-case assessment of the health effects,
significant risk, material impairment of health, available sampling and
analytical methods, and technological and economic feasibility
Another special consideration was the question of dealing with substances
for which there are sampling and analytical limitations (Table I-F-E of the
Proposal, (53 FR 20978)). This was also identified as a concern in Question
9 of the Proposal (53 FR 20961). The responses to this question are detailed
in Section V of this Preamble. OSHA concurs that adequate sampling and
analytical methods are required to permit enforcement of a PEL. However,
OSHA believes that an adequate sampling and analytical method exists when
such methods are fully described in the open literature, or when otherwise
The Public Hearing did not provide much additional information regarding
sampling and analytical methods for those substances identified as having
inadequate sampling and analytical methods. However, a method was identified
for substilisins and was entered into the docket (Ex. 8-70). Included in
Table IV-E-1 of this section are the substances noted in Table I-F-E of the
Proposal (53 FR 20978) and two additional substances (oxygen difluoride and
phenylphosphine) which were inadvertently omitted from the listing of
substances with inadequate sampling or analytical methods. One substance,
cyanamide, was erroneously listed as having no method.
OSHA has also considered the concerns identified regarding the need for a
more extensively tested analytical method (Ex. 3-960; Ex. 8-47) for
enforcement purposes. OSHA believes that enforcement can be initiated
without such detailed methods. The OSHA docket includes: (1) reference to
a fully developed and extensively tested OSHA or NIOSH sampling and
analytical procedure or, (2) a description of an OSHA in-house sampling and
analytical method for all but the seven substances listed in Table IV-E-1.
OSHA therefore believes there will be no problems with enforcement of the
PELs for all but these seven substances. This is consistent with conclusions
of NIOSH regarding implementation (Ex. 8-47). Since development of sampling
and analytical procedures is a dynamic, rapidly progressing technology, OSHA
also believes it is appropriate to adopt PELs for the seven substances (based
on the Proposal and the Public Hearing record), but stay enforcement of these
PELs until adequate sampling and analytical methods are available. At such
time, OSHA will publish in the Federal Register its determination that
such methods exist (together with a copy of the method), and indicate the
proposed effective date for enforcement of the PEL for the substance in
As time, resources and priorities permit, OSHA will attempt to initiate a
program, in conjunction with NIOSH, to develop more extensively tested
sampling and analytical methods for those substances where only in-house
methods are noted in the Proposal.
OSHA further considered the three alternative approaches described in the
Proposal regarding interim procedures for handling those substances requiring
special attention (53 FR 20978-20979). OSHA encouraged public comment on this
subject by including a question (number 14) in the Proposal. The responses
to this question are detailed in Section V of this preamble and indicate the
desireability of implementing new PELs promptly, even if they represent only
Therefore, OSHA is proceeding to promulgate limits for all of the substances
included in the Proposal where statutory requirements are met, while also
identifying some substances which appear appropriate for future
Substances with Inadequate Analytical or Sampling Methods
1. Aluminum alkyls
2. Ethylidene norbornene
4. Mercury (alkyl compounds)
5. Oxygen Difluoride
7. Sulfur pentafluoride
F. Construction, Maritime and Agriculture Segments
Currently the exposure limits which apply to construction are the ACGIH
Threshold Limit Values of Air Contaminants for 1970 and certain substance
specific Sec. 6(b) standards. See 29 CFR 1926.55, 58 and 29 CFR 1910.19.
OSHA is required to consult with the Advisory Committee on Construction
Safety and Health prior to proposing new standards that have a major impact
on construction. See 29 CFR 1911.10(a). OSHA is in the process of formally
consulting with the Construction Advisory Committee. After receiving their
recommendations and studying feasibility issues for construction, OSHA
intends to propose amendments covering exposures to toxic substances in
construction reflecting the facts in this final preamble and standard, and
the views of the Construction Advisory Committee.
Parts 1916, 1917 and 1918 of 29 CFR cover, respectively, employment in
shipyards, marine terminals and longshoring. Part 1916 for shipyards
references the 1970 TLVs of the ACGIH. See 29 CFR 1915.5 and 1915.12 (b)(3).
Part 1917 for marine terminals references the current Z-Tables. See 29 CFR
1917.2 (p), and .23. Part 1918 for longshoring refers to "dangerous gaseous
contaminants not immediately dangerous to life" and "heavy concentrations of
dusts." See 29 CFR 1918.93 (e) and (f). Certain substance specific Section
6(b) standards also cover these industries. See 29 CFR 1910.19.
OSHA, as part of the rulemaking covering construction and after studying
feasibility for the maritime sectors, intends to consider applying the final
standard to the maritime sectors.
Subpart Z of 29 CFR part 1910, and the included Z-Tables specifically do not
apply to Agriculture. See 29 CFR 1928.21(b). In addition, many of the
chemicals which affect agriculture are pesticides regulated by the EPA over
which OSHA may not have jurisdiction, pursuant to 4(b)(1) of the OSHA Act.
In the future OSHA will consider, based on relevance, priorities and
administrative resources, whether or not it is appropriate to consider
coverage for agriculture.
This final regulation has been reviewed in accordance with Executive Order
12612 (52 FR 41685; October 30, 1987) regarding Federalism. Executive Order
12612 requires that agencies, to the extent possible, refrain from limiting
state policy options, consult with states prior to taking any actions that
would restrict state policy options, and take such actions only when there is
clear constitutional authority and the presence of a problem of national
scope. The Executive Order provides for preemption of state law only if
there is a clear Congressional intent for the Agency to do so. Any such
preemption is to be limited to the extent possible.
During the development of this rule, OSHA has, to the extent possible,
refrained from limiting state policy options by developing a rule that
permits flexibility on the part of the States through the use of performance
language. OSHA also consulted with the States during the public comment and
hearing period announced in the notice of proposed rulemaking for this rule.
OSHA specifically invited Stephen Cant of the State of Washington to testify
about the state's experience in a similar rulemaking. OSH will continue to
work with the States that have state occupational safety and health plans
approved under Section 18 of the OSH Act to encourage those states to develop
their own policies to achieve program objectives and will continue to work
with appropriate state officials as they present their state standards for
Section 18 of the Occupational Safety and Health Act (OSH Act), permits any
state to develop its own independent state occupational safety and health
program that provides, among other things, worker protection "at least as
effective as" that protection provided under the Federal program.
With respect to Section 4 of Executive Order 12612, Section 18 of the OSH
Act also expresses Congress' clear intent to preempt state laws relating to
issues with respect to which Federal OSHA has promulgated occupational safety
or health standards. Under the OSH Act, a state can avoid preemption only if
it submits, and obtains Federal OSHA approval of, a plan for the development
of such standards and their enforcement as mentioned above. Occupational
safety and health standards developed by such Approved Plan States must,
among other things, be as least as effective in providing safe and healthful
employment and places of employment as the Federal standards.
Under the OSH Act, if a state develops its own OSHA approved state program,
it could include additional requirements in its standards. Moreover, the
performance nature of this final rule, of and by itself, allows for
flexibility by states to provide at least as much health protection,
consonant with the conditions in each state.
In summary, there is a clear national problem, identified by Congress,
related to occupational safety and health. While the individual states, if
all acted collectively, might be able to deal with the health problems
involved, most have elected not to do so in the seventeen years since the
enactment of the OSH Act. However, some states such as Washington have taken
action. Those states which have elected to participate under Section 18 of
the OSH Act, would not be preempted by this final regulation and would be
able to address special, local conditions within the framework provided by
this standard while ensuring that their standards are at least as effective
as the Federal standard. State comments were invited on the Proposal and
those that were submitted to the record were fully considered prior to
promulgation of this Final Rule.
The agency certifies that this document has been assessed in light of the
principles, criteria, and requirements stated in sections 2 through 5 of
Executive Order 12621. There are no provisions of this rulemaking that are
inconsistent with the principles, criteria and requirements stated in
Sections 2 through 5 of Executive Order 12621. States which have approved
state occupational safety and health plans may incur additional costs
associated with standards development and enforcement as a result of this
rulemaking. Funding for these approved state plan programs is available from
OSHA under section 18 of the OSH Act. This rulemaking would not change the
State's ability to discharge traditional State governmental functions or
other aspects of State sovereignty.
The following terms and acronyms appear in the standard and the preamble
supporting it. This glossary is provided as a convenience to the reader.
ACGIH - The American Conference Governmental Industrial Hygienists is a
professional society devoted to the development of administrative and
technical aspects of worker health protection. Membership is limited to
professional personnel in governmental agencies or educational institutions
engaged in occupational safety and health programs. The ACGIH issues
guidelines and recommendations in the form of Threshold Limit Values
(TLVs(R)) which are published annually.
CAS - The Chemical Abstracts Service (CAS) Registry Number is a numeric
designation assigned by the American Chemical Society's Chemical Abstracts
Service which uniquely identifies a specific chemical compound. This entry
allows one to conclusively identify a substance regardless of the name or
naming system used.
CHRIS - The Chemical Hazards Response Information System was developed by
the U.S. Coast Guard in cooperation with the National Academy of Sciences to
provide information on the handling and disposal of toxic substances. CHRIS
consists primarily of the Hazardous Chemical Data Manual which contains
chemical, physical and health hazard data on approximately 600 hazardous
chemicals and substances; and a Hazard Assessment Computer System is an
extensive data base of the information contained in the Hazardous Chemical
HSDB - The Hazardous Substances Data Bank, a part of the National Library of
Medicine System, will soon be available on OSHA's Computerized Information
System (OCIS). This data bank, currently available through TOXNET, contains
health and safety profiles for over 4100 chemicals. It includes 144 data
elements in 10 categories including use information, substance
identification, animal and human toxicity, environmental fate, standards,
personal protective equipment, fire, physical and chemical properties.
IARC - The International Agency for Research on Cancer (IARC) is a research
organization authorized by the World Health Organization in 1965. IARC's
mission is to study the causes of cancer in the human environment. IARC has
published (and continues to update) a series of monographs on a substantial
number of toxic chemicals and substance in which the carcinogenic risk of
these chemicals is evaluated.
ILO - The International Labour Organization (ILO) is a specialized agency
associated with the United Nations. Established in 1919 as part of the
Versailles Peace Treaty, the ILO serves to band together governments,
employers, and workers of 145 nations in an international effort to improve
overall working conditions and to protect the life and health of workers.
IMIS - The Integrated Management Information System (IMIS) is a data base
developed by OSHA in 1979 with sampling information on more than 70,000
individual measurements. The IMIS contains exposure measurements obtained by
OSHA compliance officers during thousands of health inspections; it is the
most extensive data base of its kind.
Material - The term "material" is used in the original standard whereas
"substance" is used in the revision. The meaning is the same.
MSDS - The Material Safety Data Sheet (MSDS) is a compilation of data and
information on individual hazardous chemicals produced by the manufacturers
and importers of that chemical, as required by OSHA's Hazard Communication
Standard, 29 CFR 1910.1200. An MSDS contains data on chemical
identification, current exposure limits, chemical reactivity, fire and
explosion limits, and information on health hazards and emergency procedures,
spill, leak, and disposal procedures, and any needed special protection or
NIOSH - The National Institute for Occupational Safety and Health (NIOSH)
was created by the Occupational Safety and Health Act of 1970. NIOSH is part
of the Centers for Disease Control under the Department of Health and Human
Services. Its mandate includes conducting research in developing criteria
and/or recommendations to be used in setting occupational exposure standards,
identifying and evaluating workplace hazards, measurement techniques, and
control technologies, and providing professional education as well as health
and safety information.
NOES - The National Occupational Exposure Survey (NOES) is a data base
completed in 1982 by NIOSH. NOES is the successor to the first such data
base, completed by NIOSH in 1974, and known as the National Occupational
Hazard Survey (NOHS). The NOES data base contains a sample of the number of
persons exposed by substance and industry from approximately 4500 businesses
in 98 geographic areas in the U.S. These surveys provide national estimates
of potential exposure to workplace hazards, by industry and occupational
OCIS - The OSHA Computerized Information System is a comprehensive data
base that contains information and data on standards interpretation, chemical
information, hazardous waste activity, 5(a)(1) citations, a health hazard
evaluation index, training materials, and other information compiled by OSHA
on subjects related to occupational safety and health.
OSHA HS Number - A Health Standard (HS) number is a 4-digit code assigned,
for ease in reference, to each of the hazardous substances or chemicals
considered for change of PEL in this rulemaking.
PEL - Permissible Exposure Limits (PELs) are limits developed by OSHA to
indicate the maximum airborne concentration of a contaminant to which an
employee may be exposed over the duration specified by the type of PEL
assigned to that contaminant.
Proposal - Refers to the June 7, 1988, Notice of Proposed Rulemaking (NPRM),
REL - Recommended Exposure Limits (RELs) are issued by NIOSH to aid in
controlling hazards in the workplace. These limits are generally expressed
as 8 - or 10 - hour TWAs for a 40-hour workweek and/or ceiling levels with
time limits ranging from instantaneous to 120 minutes. RELs are published in
a variety of NIOSH documents.
RTECS - The Registry of Toxic Effects of Chemical Substances (RTECS) is a
data base that lists an identification number, synonyms, Department of
Transportation (DOT) hazard label information, EPA Toxic Substances Control
Act (TSCA) information, OSHA and Mine Safety and Health Administration (MSHA)
air exposure limits, and animal and human toxicologic data.
Substance - The term "substance" is used in the revised standard whereas
"material" is used in the original. The meaning is the same.
TLV(R) - The Threshold Limit Value (TLV(R)) is a registered trademark for an
exposure limit developed by the American Conference of Governmental
Industrial Hygienists (ACGIH). A listing of TLVs may be found in the ACGIH's
"Documentation of the Threshold Limit Values and Biological Exposure Indices
for 1988-1989." TLVs may be stated as a time-weighted average (TLV(R)-TWA),
a Short-Term Exposure Limit (TLV R-STEL), or a Threshold Limit Value Ceiling
(TLV(R)-C). OSHA utilized the 1987-88 TLV's as a starting point for this
TSCA - The Toxic Substances Control Act (TSCA), administered by the
Environmental Protection Agency (EPA), was passed by Congress to protect
human health and the environment by requiring testing and necessary use
restrictions to regulate the commerce of certain chemical substances.
WHO - The World Health Organization (WHO) is part of the United Nations.
WHO's programs in occupational health include development of an occupational
health information system, criteria for early detection of health impairment,
and the development of internationally recommended health-based permissible
exposure limits for occupational exposure to toxic substances.
I. Clearance of Information Collection Requirements
On March 31, 1983, the Office of Management and Budget (OMB) published a new
5 CFR Part 1320, implementing the information collection provisions of the
Paperwork Reduction Act of 1980, 44 U.S.C. 3501 et seq. [48 FR 13666]. Part
1320, which became effective on April 30, 1983, sets forth procedures for
agencies to follow in obtaining OMB clearance not later than the date of
publication of the proposal in the Federal Register for collection of
information requirements contained in proposed rules. It also requires
agencies to include a statement in the notice of proposed rulemaking
indicating that such information requirements have been submitted to OMB for
review under Section 3504(h) of the Paperwork Reduction Act. The PELs update
standard will create no additional recordkeeping requirements.
J. Maintaining Z-Tables Current
This Rulemaking was designed to overcome an 18 year gap between the 1971
adoption of the PELs in the 29 CFR 1910.1000 Z-Tables and the present.
During this time period there were extensive changes in toxicology and health
effects information, and the application of available control technologies.
This resulted in the existing Z-Tables in 29 CFR 1910.1000 being out of date
and incomplete. The new information demonstrated that some workers are not
protected from exposure levels which represent a significant risk of material
impairment of health.
Because of the magnitude of changes during this 18-year period, this
Rulemaking has involved a large number of substances and interested parties.
Consequently, OSHA designed this Rulemaking to use as a starting point the
well established TLV's and REL's. The record during the public hearing was
then used to determine the appropriate final PEL, consistent with OSHA's
As a follow-up to this Rulemaking OSHA plans to develop and implement a
methodology which will permit OSHA to keep the PELs current as time goes on.
This point was raised by several commentors during the public hearing (ORC,
TR 3-266; NAM, TR 3-338; G.E., TR 9-172), without specific detail regarding
the best procedures OSHA should follow. OSHA agrees with these suggestions,
and from the start of this Rulemaking has been considering how this objective
can be attained. The program would be designed to be applicable to all
sectors (general industry, maritime, construction, and agriculture). The
methodology adopted will be designed to avoid duplicative efforts or gaps in
coverage, to be protective of workers, and to be cost effective.
Updating the PELs in the Z-Tables on a regular basis insures that the latest
evidence is considered as it becomes available, and that appropriate action
to either reduce or increase permissible levels is initiated promptly.
Commenters to this rulemaking cited several substances for which they
believed significant new information would become available in the near
future. OSHA intends to evaluate such evidence and, if appropriate, to
initiate prompt action to revise the Z-Tables. OSHA may take such action on
a single substance or on several substances. This continual, dynamic process
of evaluation and revision, consistent with the priorities of the Agency will
insure that the Z-Tables reflect the latest scientific evidence on the risks
posed by the listed substances.
OSHA will use a variety of sources to determine which substances will be
considered for updating. Information developed as a result of NIOSH studies
and the annual updating of the TLVs will, of course, be used by OSHA.
At this time OSHA has not developed the details of the up-date process. It
is anticipated that it will be planned with regularly scheduled update
intervals, somewhere between 2 and 5 years. The process is expected to
follow full 6(b) rulemaking procedures.
[54 FR 2332, Jan. 19, 1989; 54 FR 14909, April 13, 1989; 54 FR 28154, July 5, 1989]