[Federal Register Volume 88, Number 83 (Monday, May 1, 2023)]
[Notices]
[Pages 26600-26610]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-09118]


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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

[Docket No. OSHA-2023-0004]


Traylor Bros., Inc.; Application for Modification of Permanent 
Variance and Interim Order; Grant of Interim Order

AGENCY: Occupational Safety and Health Administration (OSHA), Labor.

ACTION: Notice; request for comments.

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SUMMARY: In this notice, OSHA announces an application for modification 
of a permanent variance and for an interim order submitted by Traylor 
Bros., Inc. (Traylor). The application seeks to modify a permanent 
variance relating to work in compressed-air environments previously 
granted to Traylor to add Traylor-Sundt Joint Venture (SUNDTJV) as an 
additional employer and to add the Integrated Pipeline Tunnel Project. 
Traylor also requests an interim order to be effective until OSHA 
issues a final decision on the application. This notice presents the 
agency's preliminary findings on Traylor's application and announces 
the granting of an interim order. OSHA invites the public to submit 
comments on the variance modification application to assist the agency 
in determining whether to grant the applicant a modified permanent 
variance based on the conditions specified in this application.

DATES: Submit comments, information, documents in response to this 
notice, and request for a hearing on or before May 31, 2023. The 
Interim Order described in this notice will become effective on May 1, 
2023, and shall remain in effect until the completion of the Integrated 
Pipeline Tunnel Project, the interim order is modified or revoked, or 
OSHA makes a final decision on the application for a modified permanent 
variance.

ADDRESSES: 
    Electronically: You may submit comments and attachments 
electronically at: http://www.regulations.gov, which is the Federal 
eRulemaking Portal. Follow the instructions online for submitting 
comments.
    Facsimile: If your comments, including attachments, are not longer 
than 10 pages, you may fax them to the OSHA Docket Office at (202) 693-
1648.
    Instructions: All submissions must include the agency name and OSHA 
docket number (OSHA-2023-0004). All comments, including any personal 
information you provide, are placed in the public docket without 
change, and may be made available online at http://www.regulations.gov.
    Docket: To read or download comments or other material in the 
docket, go to http://www.regulations.gov or the OSHA Docket Office. All 
documents in the docket (including this Federal Register notice) are 
listed in the http://www.regulations.gov index; however, some 
information (e.g., copyrighted material) is not publicly available to 
read or download through the website. All submissions, including 
copyrighted material, are available for inspection at the OSHA Docket 
Office. Contact the OSHA Docket Office at (202) 693-2350 (TTY (877) 
889-5627) for assistance in locating docket submissions.

FOR FURTHER INFORMATION CONTACT: Information regarding this notice is 
available from the following sources:
    Press inquiries: Contact Mr. Frank Meilinger, Director, OSHA Office 
of Communications, U.S. Department of Labor; telephone: (202) 693-1999; 
email: [email protected].
    General and technical information: Contact Mr. Kevin Robinson, 
Director, Office of Technical Programs and Coordination Activities, 
Directorate of Technical Support and Emergency Management, Occupational 
Safety and Health Administration, U.S. Department of Labor; telephone: 
(202) 693-2110; email: [email protected].
    Copies of this Federal Register notice: Electronic copies of this 
Federal Register notice are available at http://www.regulations.gov. 
This Federal Register notice, as well as news releases and other 
relevant information, also are available at OSHA's web page at http://www.osha.gov.
    Hearing Requests: According to 29 CFR 1905.15, hearing requests 
must include: (1) a concise statement of facts detailing how the 
proposed variance modification would affect the requesting party; (2) a 
specification of any statement or representation in the variance 
application that the commenter denies, and a concise summary of the 
evidence offered in support of each denial; and (3) any views or 
arguments on any issue of fact or law presented in the variance 
application.

SUPPLEMENTARY INFORMATION: 

I. Notice of Application

    This notice addresses Traylor's application by letter dated April 
20, 2022, to modify the permanent variance granted to Traylor on March 
11, 2016 (2016 Variance) (81 FR 12954), to include an additional 
employer, the

[[Page 26601]]

Traylor-Sundt Joint Venture (SUNDTJV), which is a joint venture made up 
of two construction companies, Traylor and Sundt Construction, Inc. 
(Sundt). Traylor also requested an interim order while OSHA evaluates 
the application (OSHA-2023-0004-0002). Because the joint venture 
includes an additional employer not covered by the 2016 Variance, OSHA 
will evaluate SUNDTJV's modification request as an application for a 
new permanent variance.
    SUNDTJV was awarded the tunneling contract for the Integrated 
Pipeline Tunnel Project in Dallas, Texas (OSHA-2023-0004-0001). The 
Integrated Pipeline Tunnel Project includes two tunnels, the Cedar 
Creek Tunnel, and the Hollywood Lake Tunnel, which require two separate 
tunnel drives. This notice covers the Integrated Pipeline Tunnel 
Project only and is not applicable to future tunneling projects by 
Traylor, Sundt, or SUNDTJV.
    Specifically, this notice addresses the application by Traylor (the 
applicant) for a permanent variance and interim order from the 
provisions of the standard governing compressed air work that: (1) 
prohibit compressed-air worker exposure to pressures exceeding 50 
pounds per square inch (p.s.i.) except in an emergency (29 CFR 
1926.803(e)(5)); \1\ (2) require the use of the decompression values 
specified in decompression tables in Appendix A of the compressed-air 
standard for construction (29 CFR 1926.803(f)(1)); and (3) require the 
use of automated operational controls and a special decompression 
chamber (29 CFR 1926.803(g)(1)(iii) and .803(g)(1)(xvii), 
respectively).
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    \1\ The decompression tables in Appendix A of subpart S express 
the maximum working pressures as pounds per square inch gauge 
(p.s.i.g.), with a maximum working pressure of 50 p.s.i.g. 
Therefore, throughout this notice, OSHA expresses the 50 p.s.i. 
value specified by 29 CFR 1926.803(e)(5) as 50 p.s.i.g., consistent 
with the terminology in Appendix A, Table 1 of subpart S.
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    OSHA has previously approved nearly identical provisions when 
granting several other very similar variances, as discussed in more 
detail in section II. OSHA preliminarily concludes that the variance is 
appropriate, grants an interim order temporarily allowing the proposed 
activity, and seeks comment on the variance application.

A. Background

    The variance application seeks a permanent variance for Traylor-
Sundt Joint Venture (SUNDTJV)'s work on the Integrated Pipeline Tunnel 
Project. SUNDTJV is a contractor that works on complex tunnel projects 
using innovations in tunnel-excavation methods. SUNDTJV's workers 
engage in the construction of tunnels using advanced shielded 
mechanical excavation techniques in conjunction with an earth pressure 
balance tunnel boring machine (TBM). Using shielded mechanical 
excavation techniques, in conjunction with precast concrete tunnel 
liners and backfill grout, TBMs provide methods to achieve the face 
pressures required to maintain a stabilized tunnel face through various 
geologies and isolate that pressure to the forward section (the working 
chamber) of the TBM.
    SUNDTJV asserts that it bores tunnels using TBM at levels below the 
water table through soft soils consisting of clay, silt, and sand. TBMs 
are capable of maintaining pressure at the tunnel face, and stabilizing 
existing geological conditions, through the controlled use of a 
mechanically driven cutter head, bulkheads within the shield, ground-
treatment foam, and a screw conveyor that moves excavated material from 
the working chamber. The forward-most portion of the TBM is the working 
chamber, and this chamber is the only pressurized segment of the TBM. 
Within the shield, the working chamber consists of two sections: the 
forward working chamber and the staging chamber. The forward working 
chamber is immediately behind the cutter head and tunnel face. The 
staging chamber is behind the forward working chamber and between the 
man-lock door and the entry door to the forward working chamber.
    The TBM has twin man-locks located between the pressurized working 
chamber and the non-pressurized portion of the machine. Each man-lock 
has two compartments. This configuration allows workers to access the 
man-locks for compression and decompression, and medical personnel to 
access the man-locks if required in an emergency.
    SUNDTJV's Hyperbaric Operations Manual (HOM) for the Integrated 
Pipeline Tunnel Project (OSHA-2023-0004-0003) indicates that the 
maximum pressure to which it is likely to expose workers during project 
interventions for the two tunnel drives (Cedar Creek Tunnel and 
Hollywood Lake Tunnel) associated with the Integrated Pipeline Tunnel 
Project is 58 p.s.i. Therefore, to work effectively, SUNDTJV must 
perform hyperbaric interventions in compressed air at pressures nearly 
15% higher than the maximum pressure specified by the existing OSHA 
standard, 29 CFR 1926.803(e)(5), which states: ``No employee shall be 
subjected to pressure exceeding 50 pounds per square inch except in 
emergency'' (see footnote 1).
    SUNDTJV employs specially trained personnel for the construction of 
the tunnel. To keep the machinery working effectively, SUNDTJV asserts 
that these workers must periodically enter the excavation working 
chamber of the TBM to perform hyperbaric interventions during which 
workers would be exposed to air pressures up to 58 p.s.i., which 
exceeds the maximum pressure specified by the existing OSHA standard at 
29 CFR 1926.803(e)(5). These interventions consist of conducting 
inspections or maintenance work on the cutter-head structure and 
cutting tools of the TBM, such as changing replaceable cutting tools 
and disposable wear bars, and, in rare cases, repairing structural 
damage to the cutter head. These interventions are the only time that 
workers are exposed to compressed air. Interventions in the working 
chamber (the pressurized portion of the TBM) take place only after 
halting tunnel excavation and preparing the machine and crew for an 
intervention.
    During interventions, workers enter the working chamber through one 
of the twin man-locks that open into the staging chamber. To reach the 
forward part of the working chamber, workers pass through a door in a 
bulkhead that separates the staging chamber from the forward working 
chamber. The man-locks and the working chamber are designed to 
accommodate three people, which is the maximum crew size allowed under 
the proposed variance. When the required decompression times are 
greater than work times, the twin man-locks allow for crew rotation. 
During crew rotation, one crew can be compressing or decompressing 
while the second crew is working. Therefore, the working crew always 
has an unoccupied man-lock at its disposal.
    SUNDTJV asserts that these innovations in tunnel excavation have 
greatly reduced worker exposure to hazards of pressurized air work 
because they have eliminated the need to pressurize the entire tunnel 
for the project and would thereby reduce the number of workers exposed, 
as well as the total duration of exposure, to hyperbaric pressure 
during tunnel construction. These advances in technology substantially 
modified the methods used by the construction industry to excavate 
subaqueous tunnels compared to caisson work.
    In addition to the reduced exposures resulting from the innovations 
in tunnel-excavation methods, SUNDTJV asserts that innovations in 
hyperbaric medicine and technology improve the

[[Page 26602]]

safety of decompression from hyperbaric exposures. These procedures, 
however, would deviate from the decompression process that OSHA 
requires for construction in 29 CFR 1926.803(e)(5) and (f)(1) and the 
decompression tables in Appendix A of 29 CFR 1926, subpart S. 
Nevertheless, according to SUNDTJV, their use of decompression 
protocols incorporating oxygen is more efficient, effective, and safer 
for tunnel workers than compliance with the decompression tables 
specified by the existing OSHA standard.
    SUNDTJV therefore believes its workers will be at least as safe 
under its proposed alternatives as they would be under OSHA's standard 
because of the reduction in number of workers and duration of 
hyperbaric exposures, better application of hyperbaric medicine, and 
the development of a project-specific HOM that requires specialized 
medical support and hyperbaric supervision to provide assistance to a 
team of specially trained man-lock attendants and hyperbaric or 
compressed-air workers (CAWs).
    Based on an initial review of the application for a permanent 
variance and interim order for the construction of the Integrated 
Pipeline Tunnel Project in Dallas, Texas, OSHA has preliminarily 
determined that Traylor has proposed an alternative that would provide 
a workplace at least as safe and healthful as that provided by the 
standard.

II. The Variance Application

    Pursuant to the requirements of OSHA's variance regulations (29 CFR 
part 1905), the applicant has certified that it notified its workers 
\2\ of the variance modification application and request for interim 
order by posting, at prominent locations where it normally posts 
workplace notices, a summary of the application and information 
specifying where the workers can examine a copy of the application.
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    \2\ See the definition of ``Affected employee or worker'' in 
section V.D of this notice.
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A. OSHA History of Approval of Nearly Identical Variance Requests

    OSHA has previously approved several nearly identical variances 
involving the same types of tunneling equipment used for similar 
projects (tunnel construction variances). OSHA notes that it granted 
seven subaqueous tunnel construction permanent variances from the same 
provisions of OSHA's compressed-air standard (29 CFR 1926.803(e)(5), 
(f)(1), (g)(1)(iii), and (g)(1)(xvii)) that are the subject of the 
present application: (1) Impregilo, Healy, Parsons, Joint Venture (IHP 
JV) for the completion of the Anacostia River Tunnel in Washington, DC 
(80 FR 50652, August 20, 2015); (2) Traylor JV for the completion of 
the Blue Plains Tunnel in Washington, DC (80 FR 16440, March 27, 2015); 
(3) Tully/OHL USA Joint Venture for the completion of the New York 
Economic Development Corporation's New York Siphon Tunnel project (79 
FR 29809, May 23, 2014); (4) Salini-Impregilo/Healy Joint Venture for 
the completion of the Northeast Boundary Tunnel in Washington, DC (85 
FR 27767, May 11, 2020); (5) Traylor-Shea Joint Venture for the 
completion of the Alexandria RiverRenew Tunnel Project in Alexandria, 
Virginia and Washington, DC (88 FR 15090, March 10, 2023); and (6) 
McNally/Kiewit Joint Venture for the completion of the Shoreline 
Storage Tunnel Project in Cleveland, Ohio (88 FR 15080, September 25, 
2022). OSHA also granted an interim order to Ballard Marine for the 
Suffolk County Outfall Tunnel project in West Babylon, New York (86 FR 
5253, January 19, 2021). The proposed alternate conditions in this 
notice are nearly identical to the alternate conditions of the previous 
permanent variances. OSHA is not aware of any injuries or other safety 
issues that arose from work performed under these conditions in 
accordance with the previous variances.

B. Variance From Paragraph (e)(5) of 29 CFR 1926.803, Prohibition of 
Exposure to Pressure Greater Than 50 p.s.i.

    The applicant states that it may perform hyperbaric interventions 
at pressures up to 58 p.s.i. in the working chamber of the TBM; this 
pressure exceeds the pressure limit of 50 p.s.i. specified for 
nonemergency purposes by 29 CFR 1926.803(e)(5). The TBM has twin man-
locks, with each man-lock having two compartments. This configuration 
allows workers to access the man-locks for compression and 
decompression, and medical personnel to access the man-locks if 
required in an emergency.
    TBMs are capable of maintaining pressure at the tunnel face, and 
stabilizing existing geological conditions, through the controlled use 
of a mechanically driven cutter head, bulkheads within the shield, 
ground-treatment foam, and a screw conveyor that moves excavated 
material from the working chamber. As noted earlier, the forward-most 
portion of the TBM is the working chamber, and this chamber is the only 
pressurized segment of the TBM. Within the shield, the working chamber 
consists of two sections: the staging chamber and the forward working 
chamber. The staging chamber is the section of the working chamber 
between the man-lock door and the entry door to the forward working 
chamber. The forward working chamber is immediately behind the cutter 
head and tunnel face.
    SUNDTJV will pressurize the working chamber to the level required 
to maintain a stable tunnel face. Pressure in the staging chamber 
ranges from atmospheric (no increased pressure) to a maximum pressure 
equal to the pressure in the working chamber. The applicant asserts 
that they may have to perform interventions at pressures up to 58 
p.s.i.
    During interventions, workers enter the working chamber through one 
of the twin man-locks that open into the staging chamber. To reach the 
forward part of the working chamber, workers pass through a door in a 
bulkhead that separates the staging chamber from the forward working 
chamber. The maximum crew size allowed in the forward working chamber 
is three. At certain hyperbaric pressures (i.e., when decompression 
times are greater than work times), the twin man-locks allow for crew 
rotation. During crew rotation, one crew can be compressing or 
decompressing while the second crew is working. Therefore, the working 
crew always has an unoccupied man-lock at its disposal.
    Further, the applicant has developed a project-specific HOM (OSHA-
2023-0004-0003) that describes in detail the hyperbaric procedures, the 
required medical examination used during the tunnel-construction 
project, the standard operating procedures and the emergency and 
contingency procedures. The procedures include using experienced and 
knowledgeable man-lock attendants who have the training and experience 
necessary to recognize and treat decompression illnesses and injuries. 
The attendants are under the direct supervision of the hyperbaric 
supervisor (competent person experienced and trained in hyperbaric 
operations, procedures and safety) and attending physician. In 
addition, procedures include medical screening and review of 
prospective CAWs. The purpose of this screening procedure is to vet 
prospective CAWs with medical conditions (e.g., deep vein thrombosis, 
poor vascular circulation, and muscle cramping) that could be 
aggravated by sitting in a cramped space (e.g., a man-lock) for 
extended periods or by exposure to elevated pressures and compressed 
gas mixtures. A transportable recompression chamber (shuttle) is 
available to extract workers from the hyperbaric working chamber

[[Page 26603]]

for emergency evacuation and medical treatment; the shuttle attaches to 
the topside medical lock, which is a large recompression chamber. The 
applicant believes that the procedures included in the HOM provide safe 
work conditions when interventions are necessary, including 
interventions above 50 p.s.i. or 50 p.s.i.g.
    OSHA comprehensively reviewed the project-specific HOM and 
determined that the safety and health instructions and measures it 
specifies are appropriate and adequately protect the safety and health 
of the CAWs.

C. Variance From Paragraph (f)(1) of 29 CFR 1926.803, Requirement To 
Use OSHA Decompression Tables

    OSHA's compressed-air standard for construction requires 
decompression in accordance with the decompression tables in Appendix A 
of 29 CFR 1926, subpart S (see 29 CFR 1926.803(f)(1)). As an 
alternative to the OSHA decompression tables, the applicant proposes to 
use newer decompression schedules (the 1992 French Decompression 
Tables) that rely on staged decompression and supplement breathing air 
used during decompression with air or oxygen (as appropriate).\3\ The 
applicant asserts decompression protocols using the 1992 French 
Decompression Tables for air or oxygen as specified by the Integrated 
Pipeline Tunnel Project-specific HOM are safer for tunnel workers than 
the decompression protocols specified in Appendix A of 29 CFR 1926, 
subpart S. Accordingly, the applicant would commit to following the 
decompression procedures described in that HOM, which would require it 
to follow the 1992 French Decompression Tables to decompress CAWs after 
they exit the hyperbaric conditions in the working chamber.
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    \3\ In 1992, the French Ministry of Labour replaced the 1974 
French Decompression Tables with the 1992 French Decompression 
Tables, which differ from OSHA's decompression tables in Appendix A 
by using: (1) staged decompression as opposed to continuous (linear) 
decompression; (2) decompression tables based on air or both air and 
pure oxygen; and (3) emergency tables when unexpected exposure times 
occur (up to 30 minutes above the maximum allowed working time).
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    Depending on the maximum working pressure and exposure times, the 
1992 French Decompression Tables provide for air decompression with or 
without oxygen. Traylor asserts that oxygen decompression has many 
benefits, including (1) keeping the partial pressure of nitrogen in the 
lungs as low as possible; (2) keeping external pressure as low as 
possible to reduce the formation of bubbles in the blood; (3) removing 
nitrogen from the lungs and arterial blood and increasing the rate of 
nitrogen elimination; (4) improving the quality of breathing during 
decompression stops so that workers are less tired and to prevent bone 
necrosis; (5) reducing decompression time by about 33 percent as 
compared to air decompression; and (6) reducing inflammation.
    In addition, the project-specific HOM requires a physician 
certified in hyperbaric medicine, to manage the medical condition of 
CAWs during hyperbaric exposures and decompression. A trained and 
experienced man-lock attendant is also required to be present during 
hyperbaric exposures and decompression. This man-lock attendant is to 
operate the hyperbaric system to ensure compliance with the specified 
decompression table. A hyperbaric supervisor, who is trained in 
hyperbaric operations, procedures, and safety, directly oversees all 
hyperbaric interventions and ensures that staff follow the procedures 
delineated in the HOM or by the attending physician.

D. Variance From Paragraph (g)(1)(iii) of 29 CFR 1926.803, 
Automatically Regulated Continuous Decompression

    The applicant is applying for a permanent variance from the OSHA 
standard at 29 CFR 1926.803(g)(1)(iii), which requires automatic 
controls to regulate decompression. As noted above, the applicant is 
committed to conducting the staged decompression according to the 1992 
French Decompression Tables under the direct control of the trained 
man-lock attendant and under the oversight of the hyperbaric 
supervisor.
    Breathing air under hyperbaric conditions increases the amount of 
nitrogen gas dissolved in a CAW's tissues. The greater the hyperbaric 
pressure under these conditions and the more time spent under the 
increased pressure, the greater the amount of nitrogen gas dissolved in 
the tissues. When the pressure decreases during decompression, tissues 
release the dissolved nitrogen gas into the blood system, which then 
carries the nitrogen gas to the lungs for elimination through 
exhalation. Releasing hyperbaric pressure too rapidly during 
decompression can increase the size of the bubbles formed by nitrogen 
gas in the blood system, resulting in decompression illness (DCI), 
commonly referred to as ``the bends.'' This description of the etiology 
of DCI is consistent with current scientific theory and research on the 
issue.
    The 1992 French Decompression Tables proposed for use by the 
applicant provide for stops during worker decompression (i.e., staged 
decompression) to control the release of nitrogen gas from tissues into 
the blood system. Studies show that staged decompression, in 
combination with other features of the 1992 French Decompression Tables 
such as the use of oxygen, result in a lower incidence of DCI than the 
use of automatically regulated continuous decompression.\4\ In 
addition, the applicant asserts that staged decompression administered 
in accordance with its HOM is at least as effective as an automatic 
controller in regulating the decompression process because the HOM 
includes a hyperbaric supervisor who directly supervises all hyperbaric 
interventions and ensures that the man-lock attendant, who is a 
competent person in the manual control of hyperbaric systems, follows 
the schedule specified in the decompression tables, including stops.
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    \4\ See, e.g., Dr. Eric Kindwall, EP (1997), Compressed air 
tunneling and caisson work decompression procedures: development, 
problems, and solutions. Undersea and Hyperbaric Medicine, 24(4), 
pp. 337-345. This article reported 60 treated cases of DCI among 
4,168 exposures between 19 and 31 p.s.i.g. over a 51-week contract 
period, for a DCI incidence of 1.44% for the decompression tables 
specified by the OSHA standard. Dr. Kindwall notes that the use of 
automatically regulated continuous decompression in the Washington 
State safety standards for compressed-air work (from which OSHA 
derived its decompression tables) was at the insistence of 
contractors and the union, and against the advice of the expert who 
calculated the decompression table and recommended using staged 
decompression. Dr. Kindwall then states, ``Continuous decompression 
is inefficient and wasteful. For example, if the last stage from 4 
p.s.i.g. . . . to the surface took 1h, at least half the time is 
spent at pressures less than 2 p.s.i.g. . . ., which provides less 
and less meaningful bubble suppression. . . .'' In addition, Dr. 
Kindwall addresses the continuous-decompression protocol in the OSHA 
compressed-air standard for construction, noting that ``[a]side from 
the tables for saturation diving to deep depths, no other widely 
used or officially approved diving decompression tables use straight 
line, continuous decompressions at varying rates. Stage 
decompression is usually the rule, since it is simpler to control.''
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E. Variance From Paragraph (g)(1)(xvii) of 29 CFR 1926.803, Requirement 
of Special Decompression Chamber

    The OSHA compressed-air standard for construction requires 
employers to use a special decompression chamber of sufficient size to 
accommodate all CAWs being decompressed at the end of the shift when 
total decompression time exceeds 75 minutes (see 29 CFR 
1926.803(g)(1)(xvii)). Use of the special decompression chamber enables 
CAWs to move about and flex their joints to prevent neuromuscular 
problems during decompression.
    Space limitations in the TBM do not allow for the installation and 
use of an

[[Page 26604]]

additional special decompression lock or chamber. The applicant 
proposes that it be permitted to rely on the man-locks and staging 
chamber in lieu of adding a separate, special decompression chamber. 
Because only a few workers out of the entire crew are exposed to 
hyperbaric pressure, the man-locks (which, as noted earlier, connect 
directly to the working chamber) and the staging chamber are of 
sufficient size to accommodate all of the exposed workers during 
decompression. The applicant uses the existing man-locks, each of which 
adequately accommodates a three-member crew for this purpose when 
decompression lasts up to 75 minutes. When decompression exceeds 75 
minutes, crews can open the door connecting the two compartments in 
each man-lock (during decompression stops) or exit the man-lock and 
move into the staging chamber where additional space is available. The 
applicant asserts that this alternative arrangement is as effective as 
a special decompression chamber in that it has sufficient space for all 
the CAWs at the end of a shift and enables the CAWs to move about and 
flex their joints to prevent neuromuscular problems.

III. Agency Preliminary Determinations

    After reviewing the proposed alternatives, OSHA has preliminarily 
determined that the applicant's proposed alternatives on the whole, 
subject to the conditions in the request and imposed by this interim 
order, provide measures that are as safe and healthful as those 
required by the cited OSHA standards addressed in section II of this 
notice.
    In addition, OSHA has preliminarily determined that each of the 
following alternatives are at least as effective as the specified OSHA 
requirements:

A. 29 CFR 1926.803(e)(5)

    SUNDTJV has developed, and proposed to implement, effective 
alternative measures to the prohibition of using compressed air under 
hyperbaric conditions exceeding 50 p.s.i. The proposed alternative 
measures include use of engineering and administrative controls of the 
hazards associated with work performed in compressed-air conditions 
exceeding 50 p.s.i. while engaged in the construction of a subaqueous 
tunnel using advance shielded mechanical-excavation techniques in 
conjunction with the TBM. Prior to conducting interventions in the 
TBM's pressurized working chamber, SUNDTJV halts tunnel excavation and 
prepares the machine and crew to conduct the interventions. 
Interventions involve inspection, maintenance, or repair of the 
mechanical-excavation components located in the working chamber.

B. 29 CFR 1926.803(f)(1)

    SUNDJV has proposed to implement equally effective alternative 
measures to the requirement in 29 CFR 1926.803(f)(1) for compliance 
with OSHA's decompression tables. The project-specific HOM specifies 
the procedures and personnel qualifications for performing work safely 
during the compression and decompression phases of interventions. The 
HOM also specifies the decompression tables the applicant proposes to 
use (the 1992 French Decompression Tables). Depending on the maximum 
working pressure and exposure times during the interventions, the 
tables provide for decompression using air, pure oxygen, or a 
combination of air and oxygen. The decompression tables also include 
delays or stops for various time intervals at different pressure levels 
during the transition to atmospheric pressure (i.e., staged 
decompression). In all cases, a physician certified in hyperbaric 
medicine will manage the medical condition of CAWs during 
decompression. In addition, a trained and experienced man-lock 
attendant, experienced in recognizing decompression sickness or 
illnesses and injuries, will be present. Of key importance, a 
hyperbaric supervisor, trained in hyperbaric operations, procedures, 
and safety, will directly supervise all hyperbaric operations to ensure 
compliance with the procedures delineated in the project-specific HOM 
or by the attending physician.
    Prior to granting the seven previous permanent variances to IHP JV, 
Traylor JV, Tully JV, Salini-Impregilo Joint Venture, Traylor-Shea JV 
and McNally/Kiewit JV and Ballard, OSHA conducted a review of the 
scientific literature and concluded that the alternative decompression 
method (i.e., the 1992 French Decompression Tables) SUNDTJV proposed 
would be at least as safe as the decompression tables specified by OSHA 
when applied by trained medical personnel under the conditions that 
would be imposed by the proposed variance.
    Some of the literature indicates that the alternative decompression 
method may be safer, concluding that decompression performed in 
accordance with these tables resulted in a lower occurrence of DCI than 
decompression conducted in accordance with the decompression tables 
specified by the standard. For example, H. L. Anderson studied the 
occurrence of DCI at maximum hyperbaric pressures ranging from 4 
p.s.i.g. to 43 p.s.i.g. during construction of the Great Belt Tunnel in 
Denmark (1992-1996).\5\ This project used the 1992 French Decompression 
Tables to decompress the workers during part of the construction. 
Anderson observed 6 DCI cases out of 7,220 decompression events and 
reported that switching to the 1992 French Decompression tables reduced 
the DCI incidence to 0.08% compared to a previous incidence rate of 
0.14%. The DCI incidence in the study by H. L. Andersen is 
substantially less than the DCI incidence reported for the 
decompression tables specified in Appendix A.
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    \5\ Anderson HL (2002). Decompression sickness during 
construction of the Great Belt tunnel, Denmark. Undersea and 
Hyperbaric Medicine, 29(3), pp. 172-188.
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    OSHA found no studies in which the DCI incidence reported for the 
1992 French Decompression Tables were higher than the DCI incidence 
reported for the OSHA decompression tables.\6\
---------------------------------------------------------------------------

    \6\ Le P[eacute]chon JC, Barre P, Baud JP, Ollivier F (September 
1996). Compressed air work--French Tables 1992--operational results. 
JCLP Hyperbarie Paris, Centre Medical Subaquatique Interentreprise, 
Marseille: Communication a l'EUBS, pp. 1-5 (see Ex. OSHA-2012-0036-
0005).
---------------------------------------------------------------------------

    OSHA's experience with the previous seven variances, which all 
incorporated nearly identical decompression plans and did not result in 
safety issues, also provide evidence that the alternative procedure as 
a whole is at least as effective for this type of tunneling project as 
compliance with OSHA's decompression tables. The experience of State 
Plans \7\ that either granted variances (Nevada, Oregon and Washington) 
\8\ or promulgated a new standard (California) \9\ for hyperbaric 
exposures occurring during similar subaqueous tunnel-construction work, 
provide additional evidence of the effectiveness of this alternative 
procedure.
---------------------------------------------------------------------------

    \7\ Under section 18 of the OSH Act, Congress expressly provides 
that States and U.S. territories may adopt, with Federal approval, a 
plan for the development and enforcement of occupational safety and 
health standards. OSHA refers to such States and territories as 
``State Plan States'' Occupational safety and health standards 
developed by State Plan States must be at least as effective in 
providing safe and healthful employment and places of employment as 
the Federal standards (29 U.S.C. 667).
    \8\ These state variances are available in the docket for the 
2015 Traylor JV variance: Exs. OSHA-2012-0035-0006 (Nevada), OSHA-
2012-0035-0005 (Oregon), and OSHA-2012-0035-0004 (Washington).
    \9\ See California Code of Regulations, Title 8, Subchapter 7, 
Group 26, Article 154, available at http://www.dir.ca.gov/title8/sb7g26a154.html.
---------------------------------------------------------------------------

C. 29 CFR 1926.803(g)(1)(iii)

    SUNDTJV developed, and proposed to implement, an equally effective

[[Page 26605]]

alternative to 29 CFR 1926.803(g)(1)(iii), which requires the use of 
automatic controllers that continuously decrease pressure to achieve 
decompression in accordance with the tables specified by the standard. 
The applicant's alternative includes using the 1992 French 
Decompression Tables for guiding staged decompression to achieve lower 
occurrences of DCI, using a trained and competent attendant for 
implementing appropriate hyperbaric entry and exit procedures, and 
providing a competent hyperbaric supervisor and attending physician 
certified in hyperbaric medicine to oversee all hyperbaric operations.
    In reaching this preliminary conclusion, OSHA again notes the 
experience of previous nearly identical tunneling variances, the 
experiences of State Plan States, and a review of the literature and 
other information noted earlier.

D. 29 CFR 1926.803(g)(1)(xvii)

    SUNDTJV developed, and proposed to implement, an effective 
alternative to the use of the special decompression chamber required by 
29 CFR 1926.803(g)(1)(xvii). The TBM's man-lock and working chamber 
appear to satisfy all of the conditions of the special decompression 
chamber, including that they provide sufficient space for the maximum 
crew of three CAWs to stand up and move around, and safely accommodate 
decompression times up to 360 minutes. Therefore, again noting OSHA's 
previous experience with nearly identical variances including the same 
alternative, OSHA preliminarily determined that the TBM's man-lock and 
working chamber function as effectively as the special decompression 
chamber required by the standard.
    Pursuant to section 6(d) of the Occupational Safety and Health Act 
of 1970 (29 U.S.C. 655), and based on the record discussed above, the 
agency preliminarily finds that when the employer complies with the 
conditions of the proposed modified variance, the working conditions of 
the employer's workers would be at least as safe and healthful as if 
the employer complied with the working conditions specified by 
paragraphs (e)(5), (f)(1), (g)(1)(iii), and (g)(1)(xvii) of 29 CFR 
1926.803.

IV. Grant of Interim Order, Proposal for Permanent Variance, and 
Request for Comment

    OSHA hereby announces the preliminary decision to grant an interim 
order to SUNDTJV for the Integrated Pipeline Tunnel Project in Dallas, 
Texas. This interim order permits SUNDTJV's CAWs to perform 
interventions in hyperbaric conditions not exceeding 58 p.s.i.g. during 
the Integrated Pipeline Tunnel Project, subject to the conditions that 
follow in this document. This interim order will remain in effect until 
completion of the Integrated Pipeline Tunnel Project or until the 
agency modifies or revokes the interim order or makes a final decision 
on the application for a permanent variance. During the period starting 
with the publication of this notice until completion of the Integrated 
Pipeline Tunnel Project, or until the agency modifies or revokes the 
interim order or makes a final decision on the application for a 
permanent variance, SUNDTJV is required to comply fully with the 
conditions of the interim order as an alternative to complying with the 
following requirements of 29 CFR 1926.803 (hereafter, ``the standard'') 
that:
    1. Prohibit exposure to pressure greater than 50 p.s.i. (29 CFR 
1926.803(e)(5));
    2. Require the use of decompression values specified by the 
decompression tables in Appendix A of the compressed-air standard (29 
CFR 1926.803(f)(1));
    3. Require the use of automated operational controls (29 CFR 
1926.803(g)(1)(iii)); and
    4. Require the use of a special decompression chamber (29 CFR 
1926.803(g)(1)(xvii)).
    In order to avail itself of the interim order, SUNDTJV must: (1) 
comply with the conditions listed in the interim order for the period 
starting with the grant of the interim order and ending with SUNDTJV's 
completion of the Integrated Pipeline Tunnel Project (or until the 
agency modifies or revokes the interim order or makes a decision on its 
application for a modified permanent variance); (2) comply fully with 
all other applicable provisions of 29 CFR part 1926; and (3) provide a 
copy of this Federal Register notice to all employees affected by the 
proposed conditions, including the affected employees of other 
employers, using the same means it used to inform these employees of 
its application for a modified permanent variance.
    OSHA is also proposing that the same requirements (see above 
section III, parts A through D) would apply to a permanent variance if 
OSHA ultimately issues one for this project. OSHA requests comment on 
those conditions as well as OSHA's preliminary determination that the 
specified alternatives and conditions would provide a workplace as safe 
and healthful as those required by the standard from which a variance 
is sought. After reviewing comments, OSHA will publish in the Federal 
Register the agency's final decision granting or denying a permanent 
variance.

V. Description of the Specified Conditions of the Interim Order and the 
Application for a Permanent Variance

    This section describes the alternative means of compliance with 29 
CFR 1926.803(e)(5), (f)(1), (g)(1)(iii), and (g)(1)(xvii) and provides 
additional detail regarding the proposed conditions that form the basis 
of Traylor's application for an interim order and for a modified 
permanent variance. The conditions are listed in section VI of this 
notice. For brevity, the discussion that follows refers only to the 
permanent variance, but the same conditions apply to the interim order.

Proposed Condition A: Scope

    The scope of the proposed permanent variance would limit coverage 
to the work situations specified. Clearly defining the scope of the 
proposed permanent variance provides Traylor, SUNDTJV's employees, 
potential future applicants, other stakeholders, the public, and OSHA 
with necessary information regarding the work situations in which the 
proposed permanent variance would apply. To the extent that Traylor or 
SUNDTJV exceeds the defined scope of this variance, it would be 
required to comply with OSHA's standards.
    Pursuant to 29 CFR 1905.11, an employer (or class or group of 
employers) \10\ may request a permanent variance for a specific 
workplace or workplaces. If OSHA approves a permanent variance, it 
would apply only to the specific employer(s) that submitted the 
application and only to the specific workplace or workplaces designated 
as part of the project. In this instance, if OSHA were to grant a 
modified permanent variance, it would apply to only the applicant, 
SUNDJV, and only the Integrated Pipeline Tunnel Project.
---------------------------------------------------------------------------

    \10\ A class or group of employers (such as members of a trade 
alliance or association) may apply jointly for a variance provided 
an authorized representative for each employer signs the application 
and the application identifies each employer's affected facilities.
---------------------------------------------------------------------------

Proposed Condition B: Duration

    The interim order is only intended as a temporary measure pending 
OSHA's decision on the permanent variance, so this condition specifies 
the duration of the Order. If OSHA approves a permanent variance, it 
would specify

[[Page 26606]]

the duration of the modified permanent variance as the remainder of the 
Integrated Pipeline Tunnel Project.

Proposed Condition C: List of Abbreviations

    The proposed condition defines a number of abbreviations used in 
the proposed modified permanent variance. OSHA believes that defining 
these abbreviations serve to clarify and standardize their usage, 
thereby enhancing the applicant's and its employees' understanding of 
the conditions specified by the proposed permanent variance.

Proposed Condition D: Definitions

    The proposed condition defines a series of terms, mostly technical 
terms, used in the proposed modified permanent variance to standardize 
and clarify their meaning. OSHA believes that defining these terms 
serves to enhance the applicant's and its employees' understanding of 
the conditions specified by the proposed permanent variance.

Proposed Condition E: Safety and Health Practices

    This proposed condition requires the applicant to develop and 
submit to OSHA a HOM specific to the Integrated Pipeline Tunnel Project 
at least six months before using the TBM for tunneling operations. The 
applicant must also submit, at least six months before using the TBM, 
proof that the TBM's hyperbaric chambers have been designed, 
fabricated, inspected, tested, marked, and stamped in accordance with 
the requirements of ASME PVHO-1.2019 (or the most recent edition of 
Safety Standards for Pressure Vessels for Human Occupancy). These 
requirements ensure that the applicant develops hyperbaric safety and 
health procedures suitable for the project.
    The submission of the HOM to OSHA, which SUNDTJV has already 
completed, enables OSHA to determine whether the safety and health 
instructions and measures it specifies are appropriate to the field 
conditions of the tunnel (including expected geological conditions), 
conform to the conditions of the variance, and adequately protect the 
safety and health of the CAWs. It also facilitates OSHA's ability to 
ensure that the applicant is complying with these instructions and 
measures. The requirement for proof of compliance with ASME PVHO-1.2019 
is intended to ensure that the equipment is structurally sound and 
capable of performing to protect the safety of the employees exposed to 
hyperbaric pressure.
    Additionally, the proposed condition includes a series of related 
hazard prevention and control requirements and methods (e.g., 
decompression tables, job hazard analyses (JHA), operations and 
inspections checklists, incident investigation, and recording and 
notification to OSHA of recordable hyperbaric injuries and illnesses) 
designed to ensure the continued effective functioning of the 
hyperbaric equipment and operating system.

Proposed Condition F: Communication

    This proposed condition requires the applicant to develop and 
implement an effective system of information sharing and communication. 
Effective information sharing and communication are intended to ensure 
that affected workers receive updated information regarding any safety-
related hazards and incidents, and corrective actions taken, prior to 
the start of each shift. The proposed condition also requires the 
applicant to ensure that reliable means of emergency communications are 
available and maintained for affected workers and support personnel 
during hyperbaric operations. Availability of such reliable means of 
communications would enable affected workers and support personnel to 
respond quickly and effectively to hazardous conditions or emergencies 
that may develop during TBM operations.

Proposed Condition G: Worker Qualification and Training

    This proposed condition requires the applicant to develop and 
implement an effective qualification and training program for affected 
workers. The proposed condition specifies the factors that an affected 
worker must know to perform safely during hyperbaric operations, 
including how to enter, work in, and exit from hyperbaric conditions 
under both normal and emergency conditions. Having well-trained and 
qualified workers performing hyperbaric intervention work is intended 
to ensure that they recognize, and respond appropriately to, hyperbaric 
safety and health hazards. These qualification and training 
requirements enable affected workers to cope effectively with 
emergencies, as well as the discomfort and physiological effects of 
hyperbaric exposure, thereby preventing worker injury, illness, and 
fatalities.
    Paragraph (2)(e) of this proposed condition requires the applicant 
to provide affected workers with information they can use to contact 
the appropriate healthcare professionals if the workers believe they 
are developing hyperbaric-related health effects. This requirement 
provides for early intervention and treatment of DCI and other health 
effects resulting from hyperbaric exposure, thereby reducing the 
potential severity of these effects.

Proposed Condition H: Inspections, Tests, and Accident Prevention

    Proposed Condition H requires the applicant to develop, implement, 
and operate a program of frequent and regular inspections of the TBM's 
hyperbaric equipment and support systems, and associated work areas. 
This condition would help to ensure the safe operation and physical 
integrity of the equipment and work areas necessary to conduct 
hyperbaric operations. The condition would also enhance worker safety 
by reducing the risk of hyperbaric-related emergencies.
    Paragraph (3) of this proposed condition requires the applicant to 
document tests, inspections, corrective actions, and repairs involving 
the TBM, and maintain these documents at the jobsite for the duration 
of the job. This requirement would provide the applicant with 
information needed to schedule tests and inspections to ensure the 
continued safe operation of the equipment and systems, and to determine 
that the actions taken to correct defects in hyperbaric equipment and 
systems were appropriate, prior to returning them to service.

Proposed Condition I: Compression and Decompression

    This proposed condition would require the applicant to consult with 
the designated medical advisor regarding special compression or 
decompression procedures appropriate for any unacclimated CAW and then 
implement the procedures recommended by the medical consultant. This 
proposed provision would ensure that the applicant consults with the 
medical advisor, and involves the medical advisor in the evaluation, 
development, and implementation of compression or decompression 
protocols appropriate for any CAW requiring acclimation to the 
hyperbaric conditions encountered during TBM operations. Accordingly, 
CAWs requiring acclimation would have an opportunity to acclimate prior 
to exposure to these hyperbaric conditions. OSHA believes this 
condition would prevent or reduce adverse reactions among CAWs to the 
effects of compression or decompression associated with the 
intervention work they perform in the TBM.

Proposed Condition J: Recordkeeping

    Under OSHA's existing recordkeeping requirements in 29 CFR part 
1904

[[Page 26607]]

regarding Recording and Reporting Occupational Injuries and Illnesses, 
the employer must maintain a record of any recordable injury, illness, 
or fatality (as defined by 29 CFR part 1904) resulting from exposure of 
an employee to hyperbaric conditions by completing the OSHA Form 301 
Incident Report and OSHA Form 300 Log of Work Related Injuries and 
Illnesses. The applicant did not seek a variance from this standard and 
therefore SUNDTJV must comply fully with those requirements.
    Examples of important information to include on the OSHA Form 301 
Injury and Illness Incident Report (along with the corresponding 
questions on the form) are:

Q14

     the task performed;
     the composition of the gas mixture (e.g., air or oxygen);
     an estimate of the CAW's workload;
     the maximum working pressure;
     temperature in the work and decompression environments;
     unusual occurrences, if any, during the task or 
decompression

Q15

     time of symptom onset;
     duration between decompression and onset of symptoms

Q16

     type and duration of symptoms;
     a medical summary of the illness or injury

Q17

     duration of the hyperbaric intervention;
     possible contributing factors;
     the number of prior interventions completed by the injured 
or ill CAW; and the pressure to which the CAW was exposed during those 
interventions.\11\
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    \11\ See 29 CFR 1904 Recording and Reporting Occupational 
Injuries and Illnesses (http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9631); recordkeeping 
forms and instructions (http://www.osha.gov/recordkeeping/RKform300pkg-fillable-enabled.pdf); and OSHA Recordkeeping Handbook 
(http://www.osha.gov/recordkeeping/handbook/index.html).
---------------------------------------------------------------------------

    Proposed Condition J would add additional reporting 
responsibilities, beyond those already required by the OSHA standard. 
The applicant would be required to maintain records of specific factors 
associated with each hyperbaric intervention. The information gathered 
and recorded under this provision, in concert with the information 
provided under proposed Condition K (using OSHA Form 301 Injury and 
Illness Incident Report to investigate and record hyperbaric recordable 
injuries as defined by 29 CFR 1904.4, 1904.7, 1904.8-1904.12), would 
enable the applicant and OSHA to assess the effectiveness of the 
permanent variance in preventing DCI and other hyperbaric-related 
effects.

Proposed Condition K: Notifications

    Under the proposed condition, the applicant is required, within 
specified periods of time, to notify OSHA of: (1) any recordable 
injury, illness, in-patient hospitalization, amputation, loss of an 
eye, or fatality that occurs as a result of hyperbaric exposures during 
TBM operations within 8 hours; (2) provide OSHA a copy of the 
hyperbaric exposures incident investigation report (using OSHA Form 301 
Injury and Illness Incident Report) of these events within 24 hours of 
the incident; (3) include on OSHA Form 301 Injury and Illness Incident 
Report information on the hyperbaric conditions associated with the 
recordable injury or illness, the root-cause determination, and 
preventive and corrective actions identified and implemented; (4) 
provide the certification along with the OSHA Form 310, that affected 
workers were informed of the incident and the results of the incident 
investigation; (5) notify OSHA's Office of Technical Programs and 
Coordination Activities (OTPCA) and the OSHA Area Office in Dallas, 
Texas within 15 working days should the applicant need to revise the 
HOM to accommodate changes in its compressed-air operations that affect 
SUNDTJV's ability to comply with the conditions of the proposed 
modified permanent variance; and (6) provide OTPCA and the OSHA Area 
Office in Dallas, Texas, at the end of the project, with a report 
evaluating the effectiveness of the decompression tables within 30 days 
of the completion of the Integrated Pipeline Tunnel Project.
    It should be noted that the requirement for completing and 
submitting the hyperbaric exposure-related (recordable) incident 
investigation report (OSHA 301 Injury and Illness Incident Report) is 
more restrictive than the current recordkeeping requirement of 
completing OSHA Form 301 Injury and Illness Incident Report within 7 
calendar days of the incident (1904.29(b)(3)). This modified, more 
stringent incident investigation and reporting requirement is 
restricted to intervention-related hyperbaric (recordable) incidents 
only. Providing rapid notification to OSHA is essential because time is 
a critical element in OSHA's ability to determine the continued 
effectiveness of the variance conditions in preventing hyperbaric 
incidents, and the applicant's identification and implementation of 
appropriate corrective and preventive actions.
    Further, these notification requirements also enable the applicant, 
its employees, and OSHA to assess the effectiveness of the permanent 
variance in providing the requisite level of safety to the applicant's 
workers and, based on this assessment, whether to revise or revoke the 
conditions of the proposed permanent variance. Timely notification 
permits OSHA to take whatever action may be necessary and appropriate 
to prevent possible further injuries and illnesses. Providing 
notification to employees informs them of the precautions taken by the 
applicant to prevent similar incidents in the future.
    Additionally, this proposed condition requires the applicant to 
notify OSHA no later than seven (7) days of having knowledge that it 
will cease to do business, have a new address or location for the main 
office, or transfer the operations covered by the proposed permanent 
variance to a successor company. In addition, the condition specifies 
that the transfer of the permanent variance to a successor company must 
be approved by OSHA. These requirements allow OSHA to communicate 
effectively with the applicant regarding the status of the proposed 
permanent variance, and expedite the agency's administration and 
enforcement of the permanent variance. Stipulating that an applicant is 
required to have OSHA's approval to transfer a variance to a successor 
company provides assurance that the successor company has knowledge of, 
and will comply with, the conditions specified by the proposed 
permanent variance, thereby ensuring the safety of workers involved in 
performing the operations covered by the proposed permanent variance.

VI. Specific Conditions of the Interim Order and the Proposed Permanent 
Variance

    The following conditions apply to the interim order OSHA is 
granting to SUNDTJV for the Integrated Pipeline Tunnel Project. These 
conditions specify the alternative means of compliance with the 
requirements of paragraphs 29 CFR 1926.803(e)(5), (f)(1), (g)(1)(iii), 
and (g)(1)(xvii). In addition, these conditions are specific to the 
alternative means of compliance with these requirements that OSHA is 
proposing for SUNDTJV's permanent variance. To simplify the 
presentation of the conditions, OSHA generally refers only to the 
conditions of the proposed permanent variance, but the same

[[Page 26608]]

conditions apply to the interim order except where otherwise noted.\12\
---------------------------------------------------------------------------

    \12\ In these conditions, OSHA is using the future conditional 
form of the verb (e.g., ``would''), which pertains to the 
application for a permanent variance (designated as ``Permanent 
Variance'') but the conditions are mandatory for purposes of the 
interim order.
---------------------------------------------------------------------------

    The conditions would apply with respect to all employees of SUNDTJV 
exposed to hyperbaric conditions. These conditions are outlined in this 
section:

A. Scope

    The interim order applies, and the permanent variance would apply, 
only when SUNDTJV stops the tunnel-boring work, pressurizes the working 
chamber, and the CAWs either enter the working chamber to perform an 
intervention (i.e., inspect, maintain, or repair the mechanical-
excavation components), or exit the working chamber after performing 
interventions.
    The interim order and proposed permanent variance apply only to 
work:
    1. That occurs in conjunction with construction of the Integrated 
Pipeline Tunnel Project, a tunnel constructed using advanced shielded 
mechanical-excavation techniques and involving operation of an TBM;
    2. In the TBM's forward section (the working chamber) and 
associated hyperbaric chambers used to pressurize and decompress 
employees entering and exiting the working chamber; and
    3. Performed in compliance with all applicable provisions of 29 CFR 
part 1926 except for the requirements specified by 29 CFR 
1926.803(e)(5), (f)(1), (g)(1)(iii), and (g)(1)(xvii).

B. Duration

    The interim order granted to Traylor will remain in effect until 
SUNDTJV completes the Integrated Pipeline Tunnel Project, OSHA modifies 
or revokes this interim order, or OSHA grants Traylor's request for a 
permanent variance. The proposed permanent variance, if granted, would 
remain in effect until the completion of SUNDTJV's Integrated Pipeline 
Tunnel Project or until modified or revoked by OSHA pursuant to 29 CFR 
1905.13(a)(2).

C. List of Abbreviations

    Abbreviations used throughout this proposed permanent variance 
would include the following:

1. CAW--Compressed-air worker
2. CFR--Code of Federal Regulations
3. DCI--Decompression Illness
4. DMT--Diver Medical Technician
5. TBM--Earth Pressure Balanced Tunnel Boring Machine
6. HOM--Hyperbaric Operations Manual
7. JHA--Job hazard analysis
8. OSHA--Occupational Safety and Health Administration
9. OTPCA--Office of Technical Programs and Coordination Activities

D. Definitions

    The following definitions would apply to this proposed permanent 
variance. These definitions would supplement the definitions in 
SUNDTJV's project-specific HOM.
    1. Affected employee or worker--an employee or worker who is 
affected by the conditions of this proposed modified permanent 
variance, or any one of his or her authorized representatives. The term 
``employee'' has the meaning defined and used under the Occupational 
Safety and Health Act of 1970 (29 U.S.C. 651 et seq.).
    2. Atmospheric pressure--the pressure of air at sea level, 
generally 14.7 pounds per square inch absolute (p.s.i.a)., 1 atmosphere 
absolute, or 0 p.s.i.g.
    3. Compressed-air worker--an individual who is specially trained 
and medically qualified to perform work in a pressurized environment 
while breathing air at pressures not exceeding 58 p.s.i.g.
    4. Competent person--an individual who is capable of identifying 
existing and predictable hazards in the surroundings or working 
conditions that are unsanitary, hazardous, or dangerous to employees, 
and who has authorization to take prompt corrective measures to 
eliminate them.\13\
---------------------------------------------------------------------------

    \13\ Adapted from 29 CFR 1926.32(f).
---------------------------------------------------------------------------

    5. Decompression illness--an illness (also called decompression 
sickness or ``the bends'') caused by gas bubbles appearing in body 
compartments due to a reduction in ambient pressure. Examples of 
symptoms of decompression illness include, but are not limited to: 
joint pain (also known as the ``bends'' for agonizing pain or the 
``niggles'' for slight pain); areas of bone destruction (termed 
dysbaric osteonecrosis); skin disorders (such as cutis marmorata, which 
causes a pink marbling of the skin); spinal cord and brain disorders 
(such as stroke, paralysis, paresthesia, and bladder dysfunction); 
cardiopulmonary disorders, such as shortness of breath; and arterial 
gas embolism (gas bubbles in the arteries that block blood flow).\14\
---------------------------------------------------------------------------

    \14\ See Appendix 10 of ``A Guide to the Work in Compressed-Air 
Regulations 1996,'' published by the United Kingdom Health and 
Safety Executive available from NIOSH at http://www.cdc.gov/niosh/docket/archive/pdfs/NIOSH-254/compReg1996.pdf.
---------------------------------------------------------------------------

    Note: Health effects associated with hyperbaric intervention, but 
not considered symptoms of DCI, can include: barotrauma (direct damage 
to air-containing cavities in the body such as ears, sinuses, and 
lungs); nitrogen narcosis (reversible alteration in consciousness that 
may occur in hyperbaric environments and is caused by the anesthetic 
effect of certain gases at high pressure); and oxygen toxicity (a 
central nervous system condition resulting from the harmful effects of 
breathing molecular oxygen (O2) at elevated partial 
pressures).
    6. Diver Medical Technician--Member of the dive team who is 
experienced in first aid.
    7. Earth Pressure Balanced Tunnel Boring Machine--the machinery 
used to excavate a tunnel.
    8. Hot work--any activity performed in a hazardous location that 
may introduce an ignition source into a potentially flammable 
atmosphere.\15\
---------------------------------------------------------------------------

    \15\ Also see 29 CFR 1926.1202 for examples of hot work.
---------------------------------------------------------------------------

    9. Hyperbaric--at a higher pressure than atmospheric pressure.
    10. Hyperbaric intervention--a term that describes the process of 
stopping the TBM and preparing and executing work under hyperbaric 
pressure in the working chamber for the purpose of inspecting, 
replacing, or repairing cutting tools and/or the cutterhead structure.
    11. Hyperbaric Operations Manual--a detailed, project-specific 
health and safety plan developed and implemented by SUNDTJV for working 
in compressed air during the Integrated Pipeline Tunnel Project.
    12. Job hazard analysis--an evaluation of tasks or operations to 
identify potential hazards and to determine the necessary controls.
    13. Man-lock--an enclosed space capable of pressurization, and used 
for compressing or decompressing any employee or material when either 
is passing into, or out of, a working chamber.
    14. Medical Advisor--medical professional experienced in the 
physical requirements of compressed air work and the treatment of 
decompression illness.
    15. Pressure--a force acting on a unit area. Usually expressed as 
pounds per square inch (p.s.i.).
    16. p.s.i.a.--pounds per square inch absolute, or absolute 
pressure, is the sum of the atmospheric pressure and gauge pressure. At 
sea-level, atmospheric pressure is approximately 14.7 p.s.i.a. Adding 
14.7 to a pressure expressed in units of p.s.i.g. will yield the 
absolute pressure, expressed as p.s.i.a.
    17. p.s.i.g.--pounds per square inch gauge, a common unit of 
pressure;

[[Page 26609]]

pressure expressed as p.s.i.g. corresponds to pressure relative to 
atmospheric pressure. At sea-level, atmospheric pressure is 
approximately 14.7 p.s.i.a Subtracting 14.7 from a pressure expressed 
in units of p.s.i.a. yields the gauge pressure, expressed as p.s.i.g. 
At sea level the gauge pressure is 0 psig.
    18. Qualified person--an individual who, by possession of a 
recognized degree, certificate, or professional standing, or who, by 
extensive knowledge, training, and experience, successfully 
demonstrates an ability to solve or resolve problems relating to the 
subject matter, the work, or the project.\16\
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    \16\ Adapted from 29 CFR 1926.32(m).
---------------------------------------------------------------------------

    19. Working chamber--an enclosed space in the TBM in which CAWs 
perform interventions, and which is accessible only through a man-lock.

E. Safety and Health Practices

    1. SUNDTJV would have to adhere to the project-specific HOM 
submitted to OSHA as part of the application (see OSHA-2023-0004-0003). 
The HOM provides the minimum requirements regarding expected safety and 
health hazards (including anticipated geological conditions) and 
hyperbaric exposures during the tunnel-construction project.
    2. SUNDTJV would have to demonstrate that the TBM on the project is 
designed, fabricated, inspected, tested, marked, and stamped in 
accordance with the requirements of ASME PVHO-1.2019 (or most recent 
edition of Safety Standards for Pressure Vessels for Human Occupancy) 
for the TBM's hyperbaric chambers.
    3. SUNDTJV would have to implement the safety and health 
instructions included in the manufacturer's operations manuals for the 
TBM, and the safety and health instructions provided by the 
manufacturer for the operation of decompression equipment.
    4. SUNDTJV would have to ensure that there are no exposures to 
pressures greater than 58 p.s.i.g.
    5. SUNDTJV would have to ensure that air or oxygen is the only 
breathing gas in the working chamber.
    6. SUNDTJV would have to follow the 1992 French Decompression 
Tables for air or oxygen decompression as specified in the HOM; 
specifically, the extracted portions of the 1992 French Decompression 
tables titled, ``French Regulation Air Standard Tables.''
    7. SUNDTJV would have to equip man-locks used by employees with an 
air or oxygen delivery system, as specified by the HOM for the project. 
SUNDTJV would be prohibited from storing in the tunnel any oxygen or 
other compressed gases used in conjunction with hyperbaric work.
    8. Workers performing hot work under hyperbaric conditions would 
have to use flame-retardant personal protective equipment and clothing.
    9. In hyperbaric work areas, SUNDTJV would have to maintain an 
adequate fire-suppression system approved for hyperbaric work areas.
    10. SUNDTJV would have to develop and implement one or more Job 
Hazard Analysis (JHA) for work in the hyperbaric work areas, and 
review, periodically and as necessary (e.g., after making changes to a 
planned intervention that affects its operation), the contents of the 
JHAs with affected employees. The JHAs would have to include all the 
job functions that the risk assessment \17\ indicates are essential to 
prevent injury or illness.
---------------------------------------------------------------------------

    \17\ See ANSI/AIHA Z10-2012, American National Standard for 
Occupational Health and Safety Management Systems, for reference.
---------------------------------------------------------------------------

    11. SUNDTJV would have to develop a set of checklists to guide 
compressed-air work and ensure that employees follow the procedures 
required by the proposed modified permanent variance and this interim 
order (including all procedures required by the HOM approved by OSHA 
for the project, which this proposed variance would incorporate by 
reference). The checklists would have to include all steps and 
equipment functions that the risk assessment indicates are essential to 
prevent injury or illness during compressed-air work.
    12. SUNDTJV would have to ensure that the safety and health 
provisions of this project-specific HOM adequately protect the workers 
of all contractors and subcontractors involved in hyperbaric operations 
for the project to which the HOM applies.

F. Communication

    SUNDTJV would have to:
    1. Prior to beginning a shift, implement a system that informs 
workers exposed to hyperbaric conditions of any hazardous occurrences 
or conditions that might affect their safety, including hyperbaric 
incidents, gas releases, equipment failures, earth or rock slides, 
cave-ins, flooding, fires, or explosions.
    2. Provide a power-assisted means of communication among affected 
workers and support personnel in hyperbaric conditions where unassisted 
voice communication is inadequate.
    (a) Use an independent power supply for powered communication 
systems, and these systems would have to operate such that use or 
disruption of any one phone or signal location will not disrupt the 
operation of the system from any other location.
    (b) Test communication systems at the start of each shift and as 
necessary thereafter to ensure proper operation.

G. Worker Qualifications and Training

    SUNDTJV would have to:
    1. Ensure that each affected worker receives effective training on 
how to safely enter, work in, exit from, and undertake emergency 
evacuation or rescue from, hyperbaric conditions, and document this 
training.
    2. Provide effective instruction on hyperbaric conditions, before 
beginning hyperbaric operations, to each worker who performs work, or 
controls the exposure of others, and document this instruction. The 
instruction would need to include:
    (a) The physics and physiology of hyperbaric work;
    (b) Recognition of pressure-related injuries;
    (c) Information on the causes and recognition of the signs and 
symptoms associated with decompression illness, and other hyperbaric 
intervention-related health effects (e.g., barotrauma, nitrogen 
narcosis, and oxygen toxicity);
    (d) How to avoid discomfort during compression and decompression;
    (e) Information the workers can use to contact the appropriate 
healthcare professionals should the workers have concerns that they may 
be experiencing adverse health effects from hyperbaric exposure; and
    (f) Procedures and requirements applicable to the employee in the 
project-specific HOM.
    3. Repeat the instruction specified in paragraph (G) of this 
proposed condition periodically and as necessary (e.g., after making 
changes to its hyperbaric operations).
    4. When conducting training for its hyperbaric workers, make this 
training available to OSHA personnel and notify the OTPCA at OSHA's 
national office and OSHA's Dallas Area Office before the training takes 
place.

H. Inspections, Tests, and Accident Prevention

    1. SUNDTJV would have to initiate and maintain a program of 
frequent and regular inspections of the TBM's hyperbaric equipment and 
support systems (such as temperature control, illumination, 
ventilation, and fire-prevention and fire-suppression systems), and 
hyperbaric work areas, as required under 29 CFR 1926.20(b)(2), 
including:

[[Page 26610]]

    (a) Developing a set of checklists to be used by a competent person 
in conducting weekly inspections of hyperbaric equipment and work 
areas; and
    (b) Ensuring that a competent person conducts daily visual checks 
and weekly inspections of the TBM.
    2. Remove from service any equipment that constitutes a safety 
hazard until it corrects the hazardous condition and has the correction 
approved by a qualified person.
    3. SUNDTJV would have to maintain records of all tests and 
inspections of the TBM, as well as associated corrective actions and 
repairs, at the job site for the duration of the tunneling project and 
for 90 days after the final project report is submitted to OSHA.

I. Compression and Decompression

    SUNDTJV would have to consult with its attending physician 
concerning the need for special compression or decompression exposures 
appropriate for CAWs not acclimated to hyperbaric exposure.

J. Recordkeeping

    In addition to completing OSHA Form 301 Injury and Illness Incident 
Report and OSHA Form 300 Log of Work-Related Injuries and Illnesses, 
SUNDTJV would have to maintain records of:
    1. The date, times (e.g., time compression started, time spent 
compressing, time performing intervention, time spent decompressing), 
and pressure for each hyperbaric intervention.
    2. The names of all supervisors and DMTs involved for each 
intervention.
    3. The name of each individual worker exposed to hyperbaric 
pressure and the decompression protocols and results for each worker.
    4. The total number of interventions and the amount of hyperbaric 
work time at each pressure.
    5. The results of the post-intervention physical assessment of each 
CAW for signs and symptoms of decompression illness, barotrauma, 
nitrogen narcosis, oxygen toxicity or other health effects associated 
with work in compressed air for each hyperbaric intervention.

K. Notifications

    1. To assist OSHA in administering the conditions specified herein, 
SUNDTJV would have to:
    (a) Notify the OTPCA and the OSHA Area Office in Dallas, Texas at 
www.osha.gov/contactus/byoffice of any recordable injury, illness, or 
fatality (by submitting the completed OSHA Form 301 Injuries and 
Illness Incident Report) resulting from exposure of an employee to 
hyperbaric conditions, including those that do not require 
recompression treatment (e.g., nitrogen narcosis, oxygen toxicity, 
barotrauma), but still meet the recordable injury or illness criteria 
of 29 CFR 1904. The notification would have to be made within 8 hours 
of the incident or 8 hours after becoming aware of a recordable injury, 
illness, or fatality; a copy of the incident investigation (OSHA Form 
301 Injuries and Illness Incident Report) must be submitted to OSHA 
within 24 hours of the incident or 24 hours after becoming aware of a 
recordable injury, illness, or fatality. In addition to the information 
required by OSHA Form 301 Injuries and Illness Incident Report, the 
incident-investigation report would have to include a root-cause 
determination, and the preventive and corrective actions identified and 
implemented.
    (b) Provide certification to the OSHA Area Office in Dallas, Texas 
within 15 working days of the incident that SUNDTJV informed affected 
workers of the incident and the results of the incident investigation 
(including the root-cause determination and preventive and corrective 
actions identified and implemented).
    (c) Notify the OTPCA and the OSHA Area Office in Dallas, Texas 
within 15 working days and in writing, of any change in the compressed-
air operations that affects SUNDTJV's ability to comply with the 
proposed conditions specified herein.
    (d) Upon completion of the Integrated Pipeline Tunnel Project, 
evaluate the effectiveness of the decompression tables used throughout 
the project, and provide a written report of this evaluation to the 
OTPCA and the OSHA Area Office in Dallas, Texas within 30 days after 
the workers final day onsite.

    Note:  The evaluation report would have to contain summaries of: 
(1) The number, dates, durations, and pressures of the hyperbaric 
interventions completed; (2) decompression protocols implemented 
(including composition of gas mixtures (air and/or oxygen), and the 
results achieved; (3) the total number of interventions and the 
number of hyperbaric incidents (decompression illnesses and/or 
health effects associated with hyperbaric interventions as recorded 
on OSHA Form 301 Injuries and Illness Incident Report and OSHA Form 
300 Log of Work-Related Injuries and Illnesses, and relevant medical 
diagnoses, and treating physicians' opinions); and (4) root causes 
of any hyperbaric incidents, and preventive and corrective actions 
identified and implemented.

    (e) To assist OSHA in administering the proposed conditions 
specified herein, inform the OTPCA and the OSHA Area Office in Dallas, 
Texas as soon as possible, but no later than seven (7) days, after it 
has knowledge that it will:
    (i) Cease doing business;
    (ii) Change the location and address of the main office for 
managing the tunneling operations specified herein; or
    (iii) Transfer the operations specified herein to a successor 
company.
    (f) Notify all affected employees of this proposed modified 
permanent variance by the same means required to inform them of its 
application for a modified permanent variance.
    2. OSHA would have to approve the transfer of the proposed modified 
permanent variance to a successor company through a new application for 
a modified variance.

VII. Authority and Signature

    James S. Frederick, Deputy Assistant Secretary of Labor for 
Occupational Safety and Health, 200 Constitution Avenue NW, Washington, 
DC 20210, authorized the preparation of this notice. Accordingly, the 
agency is issuing this notice pursuant to 29 U.S.C. 655(6)(d), 
Secretary of Labor's Order No. 8-2020 (85 FR 58393, Sept. 18, 2020), 
and 29 CFR 1905.11.

    Signed at Washington, DC, on April 24, 2023.
James S. Frederick,
Deputy Assistant Secretary of Labor for Occupational Safety and Health.
[FR Doc. 2023-09118 Filed 4-28-23; 8:45 am]
BILLING CODE 4510-26-P