Document ID: OSHA-2018-0013-0001
Agency: osha
Document Type: Notice
Title: Salini-Impregilo/Healy Joint Venture; Application for Permanent Variance
and Interim Order; Grant of Interim Order; Request for Comments
Posted Date: 2019-08-27T04:00Z

[Federal Register Volume 84, Number 166 (Tuesday, August 27, 2019)]
[Notices]
[Pages 44932-44942]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-18377]

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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

[Docket No. OSHA-2018-0013]

Salini-Impregilo/Healy 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 Salini-
Impregilo/Healy 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 to grant the Permanent Variance. OSHA also 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 September 26, 2019. The 
Interim Order described in this notice will become effective on August 
27, 2019, and shall remain in effect until the completion of the 
Northeast Boundary Tunnel project for Washington, DC 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-2018-0013, 
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-2018-0013). 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: meilinger.francis2@dol.gov.

[[Page 44933]]

    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: robinson.kevin@dol.gov.
    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 
October 19, 2017, Salini-Impregilo/Healy Joint Venture (``Salini'' or 
``the applicant''), 2600 Independence Avenue SE, Washington, DC 20003, 
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 subpart S, and an Interim Order 
allowing it to proceed while OSHA considers the request for a Permanent 
Variance (OSHA-2018-0013-0001). This notice addresses Salini's 
application for a Permanent Variance and Interim Order for construction 
of the Northeast Boundary Tunnel Project in Washington, DC only and is 
not applicable to future Salini or Salini-related joint venture 
tunneling projects.
    Specifically, this notice addresses Salini's application for a 
Permanent Variance and Interim Order from the provisions of the 
standard that: (1) Require the use of the decompression values 
specified in decompression tables in Appendix A of subpart S (29 CFR 
1926.803(f)(1)); and (2) require the use of automated operational 
controls and a special decompression chamber (29 CFR 
1926.803(g)(1)(iii) and (xvii), respectively).
    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.

Background

    The applicant is a contractor that works on complex 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 (EPBMTBM). Using shielded 
mechanical excavation techniques, in conjunction with precast concrete 
tunnel liners and backfill grout, EPBMTBMs 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 EPBMTBM.
    Salini asserts that generally it bores tunnels using an EPBMTBM at 
levels below the water table through soft soils consisting of clay, 
silt, and sand. EPBMTBMs are capable of maintaining pressure at the 
tunnel face, and stabilizing existing geological conditions, through 
the controlled use of propel cylinders, 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 EPBMTBM is the working chamber, and this 
chamber is the only pressurized segment of the EPBMTBM. 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 EPBMTBM 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.
    The applicant will pressurize the working chamber to the level 
required to maintain a stable tunnel face, which for this project 
Salini estimates will be up to a pressure not exceeding 50 pounds per 
square in gauge (p.s.i.g.).\1\ Pressure in the staging chamber ranges 
from atmospheric (no increased pressure) to a maximum pressure equal to 
the pressure in the forward working chamber.
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    \1\ The applicant originally requested a Variance to work up to 
pressures not exceeding 58 p.s.i.g., which would have exceeded 
OSHA's prohibition on pressures that exceed 50 p.s.i.g. (29 CFR 
1926.803(e)(5)). The application was amended to estimate that will 
be up to pressure not exceeding 50 p.s.i.g. The revision to the 
application can be found in the docket at OSHA-2018-003-0004.
    The decompression tables in Appendix A of subpart S of part 1926 
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 Sec.  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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    Salini employs specially trained personnel for the construction of 
the tunnel. To keep the machinery working effectively, Salini asserts 
that these workers must periodically enter the excavation working 
chamber of the EPBMTBM to perform hyperbaric interventions during which 
workers would be exposed to air pressures up to 50 p.s.i.g., which does 
not exceed 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 EPBMTBM, 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 EPBMTBM) 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 manlocks 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.

[[Page 44934]]

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.
    Salini 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 the caisson work regulated by the 
current OSHA compressed-air standard for construction at 29 CFR 
1926.803.
    In addition to the reduced exposures resulting from the innovations 
in tunnel-excavation methods, Salini 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(f)(1) and the decompression tables in Appendix A of 29 
CFR 1926, subpart S. Nevertheless, according to Salini, 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.
    Salini 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 Hyperbaric Operations Manual 
(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 Salini's application for a Permanent 
Variance and Interim Order for the construction of the Northeast 
Boundary Tunnel Project in Washington, DC, OSHA has preliminarily 
determined that Salini 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, the 
applicant certifies that it provided employee representatives of 
affected workers with a copy of the variance application.\2\ The 
applicant also certifies that it notified its workers of the variance 
application 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.
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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 three subaqueous tunnel 
construction Permanent Variances from the same provisions of OSHA's 
compressed-air standard (29 CFR 1926.803(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 Annacostia 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)); and (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)). The proposed alternate conditions in this notice are nearly 
identical to the alternate conditions of the previous Permanent 
Variances.\3\ 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.
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    \3\ The other variances allowed further deviation from OSHA 
standards by permitting employee exposures above 50 p.s.i.g. based 
on the composition of the soil and the amount of water that will be 
above the tunnel for various sections of this project. The current 
proposed variance includes substantively the same safeguards as the 
variances that OSHA granted previously even though employees will 
not be exposed to the higher pressures.
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B. 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).\4\ The 
applicant asserts decompression protocols using the 1992 French 
Decompression Tables for air or oxygen as specified by the Northeast 
Boundary 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 
compressed-air worker (CAWs) after they exit the hyperbaric conditions 
in the working chamber.
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    \4\ 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. Salini 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

[[Page 44935]]

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.

C. 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 (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.\5\ In 
addition, the applicant asserts that staged decompression administered 
in accordance with its HMO is at least as effective as an automatic 
controller in regulating the decompression process because the HMO 
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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    \5\ 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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D. 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 EPBMTBM 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 preliminarily 
determined that the applicants 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(f)(1)

    Salini 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,

[[Page 44936]]

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 three previous variances to IHP JV, 
Traylor JV, and Tully JV, OSHA conducted a review of the scientific 
literature and concluded that the alternative decompression method 
(i.e., the 1992 French Decompression Tables) Salini 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).\6\ 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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    \6\ 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.\7\
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    \7\ 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).
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    OSHA's experience with the previous three variances, which all 
incorporated nearly identical decompression plans and did not result in 
safety issues, also provides 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 \8\ that either granted variances (Nevada, Oregon and Washington) 
\9\ or promulgated a new standard (California) \10\ for hyperbaric 
exposures occurring during similar subaqueous tunnel-construction work, 
provide additional evidence of the effectiveness of this alternative 
procedure.
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    \8\ 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).
    \9\ 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).
    \10\ See California Code of Regulations, Title 8, Subchapter 7, 
Group 26, Article 154, available at http://www.dir.ca.gov/title8/sb7g26a154.html.
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B. 29 CFR 1926.803(g)(1)(xvii)

    Salini developed, and proposed to implement, an equally effective 
alternative to 29 CFR 1926.803(g)(1)(xvii), 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.

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

    Salini 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 EPBMTBM'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.\11\ Therefore, again noting 
OSHA's previous experience with nearly identical variances including 
the same alternative, OSHA preliminarily determined that the EPBMTBM's 
man-lock and working chamber function as effectively as the special 
decompression chamber required by the standard.
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    \11\ As part of the HOM, Salini submitted a letter from Dr. 
Tommy Love MD, asserting the safe accommodation of decompression 
times up to 360 minutes.
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    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.

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 Salini's CAWs to perform interventions in hyperbaric 
conditions not exceeding 50 p.s.i.g. during the Northeast Boundary 
Tunnel Project, subject to the conditions that follow in this document. 
This Interim Order will remain in effect until completion of the 
Northeast Boundary Tunnel Project or until the agency modifies or 
revokes the Interim Order or makes a decision on Salini's application 
for a Permanent Variance. During the period starting with the 
publication of this notice until completion of the Northeast Boundary 
Tunnel, 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. Require the use of decompression values specified by the 
decompression tables in Appendix A of the

[[Page 44937]]

compressed-air standard (29 CFR 1926.803(f)(1));
    2. Require the use of automated operational controls (29 CFR 
1926.803(g)(1)(iii)); and
    3. Require the use of a special decompression chamber 
(1926.803(g)(1)(xvii)).
    In order to avail itself of the Interim Order, Salini 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 Salini's 
completion of the Northeast Boundary Tunnel 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 IV, parts A through C) 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(f)(1), (g)(1)(iii), and (g)(1)(xvii) and provides 
additional detail regarding the proposed conditions that form the basis 
of Salini'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 Salini, Salini'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 Salini 
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) \12\ 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, Salini-
Impregilo/Healy JV and only the Northeast Boundary Tunnel Project. As a 
result, it is important to understand that if OSHA were to grant Salini 
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 does contain provisions for future modification 
of Permanent Variances to add or include additional employers if future 
joint ventures are established.
---------------------------------------------------------------------------

    \12\ 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 Northeast Boundary Tunnel 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. 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 Northeast Boundary Tunnel Project 
at least six months before using the EPBMTBM for tunneling operations. 
The applicant must also submit, at least six months before using the 
EPBMTBM, proof that the EPBMTBM's hyperbaric chambers have been 
designed, fabricated, inspected, tested, marked, and stamped in 
accordance with the requirements of ASME PVHO-1.2012 (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 Salini 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-1.2012 
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,

[[Page 44938]]

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 EPBMTBM 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 
EPBMTBM'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 EPBMTBM, 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 EPBMTBM 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 EPBMTBM.

Proposed Condition J: Recordkeeping

    Under OSHA's existing recordkeeping requirements in 29 CFR part 
1904 regarding Recording and Reporting Occupational Injuries and 
Illnesses, Salini 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.\13\
---------------------------------------------------------------------------

    \13\ 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 
EPBMTBM 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

[[Page 44939]]

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 Baltimore/Washington DC OSHA Area Office 
(BWAO) within 15 working days should the applicant need to revise the 
HOM to accommodate changes in its compressed-air operations that affect 
Salini's ability to comply with the conditions of the proposed 
Permanent Variance; and (6) provide OTPCA and the BWAO, 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 Salini. These conditions specify the alternative means of 
compliance with the requirements of paragraphs 29 CFR 1926.803 (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 (f)(1), (g)(1)(iii), and (g)(1)(xvii) 
that OSHA is proposing for Salini'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.\14\
---------------------------------------------------------------------------

    \14\ 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 Salini 
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 Salini 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 Northeast 
Boundary Tunnel Project, a tunnel constructed using advanced shielded 
mechanical-excavation techniques and involving operation of an EPBMTBM;
    2. In the EPBMTBM'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(f)(1), (g)(1)(iii), and (g)(1)(xvii).

B. Duration

    The Interim Order granted to Salini will remain in effect until 
OSHA modifies or revokes this Interim Order or grants Salini'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 Salini's Northeast Boundary 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
4. DMT--Diver Medical Technician
5. EPBMTBM--Earth Pressure Balanced Micro 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 
Salini'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.

[[Page 44940]]

    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.\15\
---------------------------------------------------------------------------

    \15\ 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).\16\
---------------------------------------------------------------------------

    \16\ 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.\17\
---------------------------------------------------------------------------

    \17\ 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 EPBMTBM 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 Salini for working 
in compressed air during the Northeast Boundary 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. 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.\18\
---------------------------------------------------------------------------

    \18\ Adapted from 29 CFR 1926.32(m).
---------------------------------------------------------------------------

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

E. Safety and Health Practices

    1. Salini would have to adhere to the project-specific HOM 
submitted to OSHA as part of the application (see OSHA-2018-2013-0002). 
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. Salini would have to demonstrate that the EPBMTBM on the project 
is designed, fabricated, inspected, tested, marked, and stamped in 
accordance with the requirements of ASME PVHO-1.2012 (or most recent 
edition of Safety Standards for Pressure Vessels for Human Occupancy) 
for the EPBMTBM's hyperbaric chambers.
    3. Salini would have to implement the safety and health 
instructions included in the manufacturer's operations manuals for the 
EPBMTBM, and the safety and health instructions provided by the 
manufacturer for the operation of decompression equipment.
    4. Salini would have to ensure that air or oxygen is the only 
breathing gas in the working chamber.
    5. Salini 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.''
    6. Salini would have to equip man-locks used by employees with an 
air or oxygen delivery system, as specified by the HOM, for the 
project. Salini would be required not to store in the tunnel any oxygen 
or other compressed gases used in conjunction with hyperbaric work.
    7. Workers performing hot work under hyperbaric conditions would 
have to use flame-retardant personal protective equipment and clothing.
    8. In hyperbaric work areas, Salini would have to maintain an 
adequate fire-suppression system approved for hyperbaric work areas.
    9. Salini 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 \19\ indicates are essential to 
prevent injury or illness.
---------------------------------------------------------------------------

    \19\ See ANSI/AIHA Z10-2012, American National Standard for 
Occupational Health and Safety Management Systems, for reference.
---------------------------------------------------------------------------

    10. Salini 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

[[Page 44941]]

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.
    Salini 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

    Salini 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

    Salini 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. Salini would have to initiate and maintain a program of frequent 
and regular inspections of the EPBMTBM'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 EPBMTBM.
    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. Salini would have to maintain records of all tests and 
inspections of the EPBMTBM, as well as associated corrective actions 
and repairs, at the job site for the duration of the job.

I. Compression and Decompression

    Salini 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, 
Salini 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, 
Salini would have to:
    (a) Notify the OTPCA and the BWAO of any recordable injury, 
illness, or fatality (by submitting the completed OSHA Form 301 
Injuries and Illness Incident Report) \20\ 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.
---------------------------------------------------------------------------

    \20\ See footnote 10.
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    (b) Provide certification to the BWAO within 15 working days of the 
incident that Salini 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 BWAO within 15 working days and in 
writing, of any change in the compressed-air operations that affects 
Salini's ability to comply with the proposed conditions specified 
herein.

[[Page 44942]]

    (d) Upon completion of the Northeast Boundary 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 BWAO.
    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 BWAO 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.

VII. Authority and Signature

    Loren Sweatt, Principal 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 Section 29 U.S.C. 655(6)(d), 
Secretary of Labor's Order No. 1-2012 (77 FR 3912, Jan. 25, 2012), and 
29 CFR 1905.11.

    Signed at Washington, DC, on August 21, 2019.
Loren Sweatt,
Principal Deputy Assistant Secretary of Labor for Occupational Safety 
and Health.
[FR Doc. 2019-18377 Filed 8-26-19; 8:45 am]
BILLING CODE 4510-26-P