Document ID: OSHA-2022-0007-0001
Agency: osha
Document Type: Notice
Title: McNally/Kiewit Shoreline Storage Tunnel Joint Venture; Application for Permanent Variance and Interim Order; Grant of Interim Order; Request for Comments
Posted Date: 2022-09-26T04:00Z

[Federal Register Volume 87, Number 185 (Monday, September 26, 2022)]
[Notices]
[Pages 58379-58389]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-20782]

[[Page 58379]]

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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

[Docket No. OSHA-2022-0007]

McNally/Kiewit Shoreline Storage Tunnel Joint Venture; 
Application for Permanent Variance and Interim Order; Grant of Interim 
Order; Request for Comments

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

ACTION: Notice.

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SUMMARY: In this notice, OSHA announces the application of McNally/
Kiewit Shoreline Storage Tunnel (SST) Joint Venture for a permanent 
variance and interim order from provisions of OSHA standards that 
regulate work in compressed air environments and presents the agency's 
preliminary finding on McNally/Kiewit's application and announces the 
granting of an interim order. OSHA invites the public to submit 
comments on the variance application to assist the agency in 
determining whether to grant the applicant a 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 October 26, 2022. The 
interim order described in this notice will become effective on 
September 26, 2022, and shall remain in effect until the completion of 
the SST project for Cleveland, Ohio or the interim order is modified or 
revoked.

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.
    Mail, hand delivery, express mail, messenger, or courier service: 
When using this method, you must submit a copy of your comments and 
attachments to the OSHA Docket Office, Docket No. OSHA-2022-0007, 
Occupational Safety and Health Administration, U.S. Department of 
Labor, Room N-3653, 200 Constitution Avenue NW, Washington, DC 20210. 
Deliveries (hand, express mail, messenger, and courier service) are 
accepted during the Docket Office's normal business hours, 10:00 a.m. 
to 3:00 p.m., ET.
    Instructions: All submissions must include the agency name and OSHA 
docket number (OSHA-2022-0007). 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 at 
the above address. 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. You may also contact Kevin Robinson, Director 
Office of Technical Programs and Coordination Activities (OTPCA) at the 
below address.

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 short and plain statement detailing how the 
proposed Variance 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

    OSHA's standards in subpart S of 29 CFR part 1926 govern 
underground construction, caissons, cofferdams, and compressed air. On 
November 12, 2021, McNally/Kiewit SST Joint Venture (``McNally'' or 
``the applicant''), 800 Westpoint Parkway, Suite 1130, Westlake, Ohio 
44145, submitted under Section 6(d) of the Occupational Safety and 
Health Act of 1970 (OSH Act; 29 U.S.C. 655) and 29 CFR 1905.11 
(variances and other relief under section 6(d)) an application for a 
permanent variance from several provisions of the OSHA standard that 
regulates work in compressed air, 1926.803 of 1926 Subpart S--
Underground Construction, Caissons, Cofferdams, and Compressed Air, and 
an interim order allowing it to proceed while OSHA considers the 
request for a permanent variance (OSHA-2022-0007-0001). This notice 
addresses McNally's application for a permanent variance and interim 
order for construction of the SST Project in Cleveland, Ohio, only and 
is not applicable to future McNally or McNally-related joint venture 
tunneling projects.
    Specifically, this notice addresses McNally's application for a 
permanent variance and interim order from the provisions of the 
standard 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 proposed 
variance is appropriate, grants an interim order temporarily allowing 
the proposed activity, and seeks comment on the proposed variance.

[[Page 58380]]

Background

    The applicant is a contractor that works on complex underground 
tunnel projects using innovations in tunnel-excavation methods. The 
applicant's workers engage in the construction of tunnels using 
advanced shielded mechanical excavation techniques in conjunction with 
an earth pressure balanced micro-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.
    McNally asserts that generally it bores tunnels using an 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.
    McNally's variance application indicated that the maximum pressure 
to which it is likely to expose workers during project interventions 
for the SST Project is 55 p.s.i. Therefore, to work effectively, 
McNally must perform hyperbaric interventions in compressed air at 
pressures 10 percent 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 p.s.i.g. except in 
emergency'' (see footnote 1).
    McNally employs specially trained personnel for the construction of 
the tunnel. To keep the machinery working effectively, McNally 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 55 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.
    McNally 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, McNally asserts that innovations in 
hyperbaric medicine and technology improve the 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 
McNally, 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.
    McNally 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, a better application of hyperbaric medicine, and 
the development of a project-specific Hyperbaric Operations Manual 
(HOM), (OSHA-2022-0007-0002) 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 McNally's application for a permanent 
variance and interim order for the construction of the SST Project in 
Cleveland, Ohio, OSHA has preliminarily determined that McNally 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 
1905.11), the applicant has certified that it notified its workers \2\ 
of the variance 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. In addition, the applicant 
informed its workers and their representatives of their rights to 
petition the Assistant Secretary of Labor for Occupational Safety and 
Health for a hearing on the variance 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. OSHA notes that it granted five subaqueous tunnel 
construction permanent variances from the same

[[Page 58381]]

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)); and (4) Salini-
Impregilo/Healy Joint Venture for the completion of the Northeast 
Boundary Tunnel in Washington, DC (85 FR 27767, May 11, 2020). OSHA has 
also granted interim orders to two applicants, Ballard Marine for the 
Suffolk County Outfall Tunnel project in West Babylon, New York (86 FR 
5253, January 19, 2021) and Traylor Shea Joint Venture for the 
Alexandria RiverRenew Tunnel Project in Alexandria, Virginia and 
Washington, DC (87 FR 54536, September 6, 2022). 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.g. (See Footnote 1)

    The applicant states that it may perform hyperbaric interventions 
at pressures up to 55 p.s.i.g. 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.
    McNally 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 55 
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 asserts that it has developed a project-
specific HOM (OSHA-2022-0007-0002) 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 and attending physician. In addition, procedures 
include medical screening and review of prospective compressed-air 
workers (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 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.g.
    OSHA comprehensively reviewed the project-specific HOM and 
determined that the safety and health instructions and measures it 
specifies are appropriate, conform with the conditions in the variance, 
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 SST 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 compressed-air worker 
(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. McNally 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

[[Page 58382]]

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 (competent person), 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

    McNally 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 (see footnote 12 in this notice discussing a 1985 NIOSH report on 
DCI).
    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 (a competent person experienced and 
trained in hyperbaric operations, procedures, and safety) 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 percent 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 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 
document.
    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)

    McNally 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 engage in the construction of a subaqueous 
tunnel using advance shielded mechanical-excavation techniques in 
conjunction with the TBM. Prior to conducting interventions

[[Page 58383]]

in the TBM's pressurized working chamber, McNally 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)

    McNally 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 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 (competent person), 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.
    As it did when granting the five previous tunneling permanent 
variances to IHP JV, Traylor JV, Tully JV Salini-Impregilo Joint 
Venture, and Ballard, OSHA conducted a review of the scientific 
literature and concluded that the alternative decompression method 
(i.e., the 1992 French Decompression Tables) McNally 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 even indicates that it 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 
percent compared to a previous incidence rate of 0.14 percent. 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.
---------------------------------------------------------------------------

    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 five previous tunneling permanent 
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)

    McNally developed, and proposed to implement, an equally effective 
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)

    McNally 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 tunneling 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 previously granted interim order, or the conditions 
of the proposed 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.

[[Page 58384]]

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

    OSHA hereby announces the preliminary decision to grant an interim 
order allowing McNally's CAWs to perform interventions in hyperbaric 
conditions not exceeding 55 p.s.i.g. during the SST Project, subject to 
the conditions that follow in this document. This interim order will 
remain in effect until completion of the SST Project or until the 
agency modifies or revokes the interim order or makes a decision on 
McNally's application for a permanent variance. During the period 
starting with the publication of this notice until completion of the 
SST Project, or until the agency modifies or revokes the interim order 
or makes a decision on its application for a permanent variance, the 
applicant 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, McNally 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 McNally's 
completion of the SST Project (or until the agency modifies or revokes 
the interim order or makes a decision on its application for a 
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 
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 approving or rejecting the request 
for 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 McNally's application for an interim order and for a permanent 
variance. The conditions are listed in Section VI. 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 McNally, McNally'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 McNally 
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 
permanent variance, it would apply to only the applicant, McNally/
Kiewit SST Joint Venture and only the Shoreline Storage Tunnel Project. 
As a result, it is important to understand that if OSHA were to grant 
McNally a permanent variance, it would not apply to any other 
employers, such as other joint ventures the applicant may undertake in 
the future. However, 29 CFR 1905.13 contains provisions for future 
modification of permanent variances to add or include additional 
employers if future joint ventures are established.
---------------------------------------------------------------------------

    \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 the duration of the permanent variance as the remainder 
of the SST Project.

Proposed Condition C: List of Abbreviations

    Proposed condition C defines a number of abbreviations used in the 
proposed permanent variance. OSHA believes that defining these 
abbreviations serves 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 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 an HOM specific to the SST 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 McNally 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

[[Page 58385]]

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 regarding Recording and Reporting Occupational Injuries and 
Illnesses, McNally 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 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 
question 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

[[Page 58386]]

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; (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 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 Cleveland Ohio OSHA Area 
Office within 15 working days should the applicant need to revise the 
HOM to accommodate changes in its compressed-air operations that affect 
McNally's ability to comply with the conditions of the proposed 
permanent variance; and (6) provide OTPCA and the Cleveland Ohio Area 
Office, at the end of the project, with a report evaluating the 
effectiveness of the decompression tables.
    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 if it ceases to do business, has a new address or location 
for the main office, or transfers 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 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 McNally/Kiewit SST Joint Venture for the Shoreline Storage 
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 the 
requirements of paragraphs 29 CFR 1926.803 (e)(5),(f)(1), (g)(1)(iii), 
and (g)(1)(xvii) that OSHA is proposing for McNally'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 conditions apply to the interim order except 
where otherwise noted.\12\
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    \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 McNally 
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 McNally 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 variance apply only to work:
    1. That occurs in conjunction with construction of the SST 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 McNally will remain in effect until 
OSHA modifies or revokes this interim order or grants McNally's request 
for a permanent variance in accordance with 29 CFR 1905.13. The 
proposed permanent variance, if granted, would remain in effect until 
the completion of McNally's Shoreline Storage Tunnel Project.

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

[[Page 58387]]

4. DMT--Diver Medical Technician
5. TBM--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 
McNally's project-specific HOM.
    1. Affected employee or worker--an employee or worker who is 
affected by the conditions of this proposed 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 50 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 Micro 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 1910.146(b).
---------------------------------------------------------------------------

    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 McNally for working 
in compressed air during the SST 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. Pressure--a force acting on a unit area. Usually expressed as 
pounds per square inch (p.s.i.).
    15. 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.
    16. p.s.i.g.--pounds per square inch gauge, a common unit of 
pressure; 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.
    17. 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).
---------------------------------------------------------------------------

    18. 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. McNally would have to adhere to the project-specific HOM 
submitted to OSHA as part of the application (see OSHA-2022-0007-0002). 
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. McNally 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. McNally 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. McNally would have to ensure that there are no exposures to 
pressures greater than 55 p.s.i.g.
    5. McNally would have to ensure that air or oxygen is the only 
breathing gas in the working chamber.
    6. McNally 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. McNally would have to equip man-locks used by employees with an 
air or oxygen delivery system, as specified by the HOM, for the 
project. McNally would be required not to store in the tunnel any 
oxygen or other compressed

[[Page 58388]]

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, McNally would have to maintain an 
adequate fire-suppression system approved for hyperbaric work areas.
    10. McNally 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.
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    \17\ See ANSI/AIHA Z10-2012, American National Standard for 
Occupational Health and Safety Management Systems, for reference.
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    11. McNally would have to develop a set of checklists to guide 
compressed-air work and ensure that employees follow the procedures 
required by the proposed 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.
    McNally 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

    McNally 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

    McNally 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)(2)(b) 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 nearest affected Area Office before the 
training takes place.

H. Inspections, Tests, and Accident Prevention

    1. McNally 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:
    (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. McNally 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 job.

I. Compression and Decompression

    McNally 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, 
McNally 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, 
McNally would have to:
    (a) Notify the OTPCA and the Cleveland, Ohio Area Office of any 
recordable injury, illness, or fatality (by submitting the completed 
OSHA Form 301 Injuries and Illness Incident Report) \18\ resulting from 
exposure of an employee to hyperbaric conditions, including those that 
do not require recompression treatment (e.g., nitrogen narcosis, oxygen 
toxicity, barotrauma),

[[Page 58389]]

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.
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    \18\ See footnote 12.
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    (b) Provide certification to the Cleveland Ohio Area Office within 
15 working days of the incident that McNally 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 Cleveland Ohio Area Office within 15 
working days and in writing, of any change in the compressed-air 
operations that affects McNally's ability to comply with the proposed 
conditions specified herein.
    (d) Upon completion of the SST 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 Cleveland Ohio 
Area Office.
    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 Cleveland Ohio Area Office 
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 permanent 
variance by the same means required to inform them of its application 
for a Variance.
    2. OSHA would have to approve the transfer of the proposed 
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(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 September 16, 2022.
James S. Frederick,
Deputy Assistant Secretary of Labor for Occupational Safety and Health.
[FR Doc. 2022-20782 Filed 9-23-22; 8:45 am]
BILLING CODE 4510-26-P