[Federal Register Volume 85, Number 91 (Monday, May 11, 2020)]
[Notices]
[Pages 27767-27775]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-09967]


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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

[Docket No. OSHA-2018-0013]


Salini-Impregilo/Healy Joint Venture: Grant of Permanent Variance

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

ACTION: Notice of permanent variance.

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SUMMARY: In this notice, OSHA grants a permanent variance to Salini-
Impregilo/Healy Joint Venture from the provisions of OSHA standards 
that regulate work in compressed-air environments.

DATES: The permanent variance specified by this notice becomes 
effective on May 11, 2020 and shall remain in effect until the 
completion of the Northeast Boundary Tunnel project.

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, phone: (202) 693-1999; email: 
meilinger.francis2@dol.gov.
    General and Technical Information: Contact 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; phone: 
(202) 693-2110 or email: robinson.kevin@dol.gov.

SUPPLEMENTARY INFORMATION: 
    Copies of this Federal Register notice: Electronic copies of this 
Federal Register notice are available at http://www.regulations.gov. 
This Federal Register notice and other relevant

information are also available at OSHA's web page at http://www.osha.gov.

I. Overview

    On October 19, 2017, OSHA received a variance application from 
Salini-Impregilo/Healy Joint Venture (``Salini'' or ``the applicant'') 
regarding the Northeast Boundary Tunnel project, which consists of 
boring a 12-foot diameter tunnel under a roadway near the Potomac River 
in Washington, DC. Salini, requested a permanent variance from several 
provisions of 29 CFR 1926.803, the OSHA standard that regulates 
construction work in compressed air environments. Specifically, Salini 
sought a variance from the provisions of the standard that: (1) 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 (2) 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).
    Salini also requested an interim order pending OSHA's decision on 
the application for a variance (Document ID No. OSHA-2018-0013-0001).
    OSHA reviewed Salini's application for the variance and interim 
order and determined that they were appropriately submitted in 
compliance with the applicable variance procedures in Section 6(d) of 
the Occupational Safety and Health Act of 1970 (``OSH Act''; 29 U.S.C. 
655) and OSHA's regulations at 29 CFR 1905.11 (``Variances and other 
relief under section 6(d)''), including the requirement that the 
applicant inform 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.
    OSHA reviewed the alternative procedures in Salini's application 
and preliminarily determined that the applicant's proposed alternatives 
on the whole, subject to the conditions in the request and imposed by 
the Interim Order, provide measures that are as safe and healthful as 
those required by the cited OSHA standards. On August 27, 2019, OSHA 
published a Federal Register notice announcing Salini's application for 
permanent variance, stating the preliminary determination along with 
the basis of that determination, and granting the Interim Order (84 FR 
44932). OSHA requested comments on each.
    OSHA did not receive any comments or other information disputing 
the preliminary determination that the alternatives were at least as 
safe as OSHA's standard, nor any objections to OSHA granting a 
permanent variance. Accordingly, through this notice OSHA grants a 
permanent variance subject to the conditions set out in this document.

II. Salini and Its Proposed Excavation Techniques and Safeguards

    The information that follows about Salini, its methods, and its 
project comes from Salini's variance application.
    Salini, which is the general contractor for the Northeast Boundary 
Tunnel Project (hereafter, ``the project''), is a contractor that works 
on complex tunnel projects using innovations in tunnel-excavation 
methods. Salini's workers engage in the construction of tunnels using 
advanced shielded mechanical excavation techniques in conjunction with 
an earth pressure balanced 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 the forward section (the working 
chamber) of the EPBMTBM.
    The project consists of a 12-foot diameter tunnel under a roadway 
near the Potomac River in Washington, DC. Salini will bore the tunnel 
below the water table through soft soils consisting of clay, silt, and 
sand. Salini employs specially trained personnel for the construction 
of the tunnel, and states that this construction will use shielded 
mechanical-excavation techniques. Salini's workers perform hyperbaric 
interventions at pressures greater than 50 p.s.i.g. in the excavation 
chamber of the EPBMTBM; these interventions consist of conducting 
inspections and maintenance work on the cutter-head structure and 
cutting tools of the EPBMTBM.
    Salini asserted in the variance application that innovations in 
tunnel excavation, specifically with EPBMTBMs, have, in most cases, 
eliminated the need to pressurize the entire tunnel. This technology 
negates the requirement that all members of a tunnel-excavation crew 
work in compressed air while excavating the tunnel. These advances in 
technology modified substantially the methods used by the construction 
industry to excavate subaqueous tunnels compared to the work regulated 
by the current OSHA compressed-air standard for construction at 29 CFR 
1926.803. Such advances reduce the number of workers exposed, and the 
total duration of exposure, to hyperbaric pressure during tunnel 
construction.
    Using shielded mechanical-excavation techniques, in conjunction 
with pre-cast concrete tunnel liners and backfill grout, EPBMTBMs 
provide methods to achieve the pressures required to maintain a 
stabilized tunnel face through various geologies, while isolating that 
pressure to the forward section (working or excavation chamber) of the 
EPBMTBM. EPBMTBMs are staffed by trained man-lock attendants and 
hyperbaric or compressed-air workers.
    Interventions involving the working chamber (the pressurized 
chamber at the head of the EPBMTBM) take place only after the applicant 
halts tunnel excavation and prepares the machine and crew for an 
intervention. Interventions occur to inspect or maintain the 
mechanical-excavation components located in the forward portion of the 
working chamber. Maintenance conducted in the forward portion of the 
working chamber includes changing replaceable cutting tools and 
disposable wear bars, and, in rare cases, making repairs to the cutter 
head due to structural damage.
    In addition to innovations in tunnel-excavation methods, research 
conducted after OSHA published its compressed-air standard for 
construction in 1971 resulted in advances in hyperbaric medicine. In 
this regard, the applicant asserts that the use of decompression 
protocols incorporating oxygen is more efficient, effective, and safer 
for tunnel workers than compliance with the existing OSHA standard (29 
CFR 1926, subpart S, Appendix A decompression tables). According to the 
applicant, workers must periodically enter the excavation working 
chamber of EPBMTBMs to hyperbaric pressures up to 50 p.s.i.g., which 
does not exceed the maximum pressure specified by the existing OSHA 
standard (29 CFR 1926.803(e)(5)). The applicant asserts that these 
hyperbaric exposures are possible because of advances in hyperbaric 
technology, a better understanding of hyperbaric medicine, and the 
development of a project-specific Hyberbaric 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 workers.
    Salini contended that the alternative safety measures included in 
the application provide Salini's workers with a place of employment 
that is at least as safe and healthful as they would obtain under the 
existing provisions of

OSHA's compressed-air standard for construction.
    OSHA included all of the above information in the Federal Register 
notice regarding Salini's variance application and did not receive any 
comments disputing any of that information, including the safety 
assertions made by Salini in the Variance application.

III. 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.\1\ 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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    \1\ 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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IV. Applicable OSHA Standard and the Relevant Variances

A. 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 (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). The applicant 
asserts decompression protocols using the 1992 French Decompression 
Tables for air or oxygen as specified by the Northeast Boundary Tunnel-
specific Hyperbaric Operations Manual (HOM) are safer for tunnel 
workers than the decompression protocols specified in Appendix A of 29 
CFR 1926, subpart S. Accordingly, the applicant commits to following 
the decompression procedures described in that HOM, which would require 
it to follow the 1992 French Decompression Tables to decompress 
compressed-air workers (CAWs) after they exit the hyperbaric conditions 
in the working chamber.
    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 
experienced man-lock attendant also will be present during hyperbaric 
exposures and decompression. This man-lock attendant will operate the 
hyperbaric system to ensure compliance with the specified decompression 
table. A hyperbaric supervisor (competent person), 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.

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

    According to the applicant, 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 DCI, commonly 
referred to as ``the bends.'' This description of the etiology of DCI 
is consistent with current scientific theory and research on the issue.
    The 1992 French Decompression Tables proposed for use by the 
applicant provide for stops during worker decompression (i.e., staged 
decompression) to control the release of nitrogen gas from tissues into 
the blood system. Studies show that staged decompression, in 
combination with other features of the 1992 French Decompression Tables 
such as the use of oxygen, result in a lower incidence of DCI than the 
use of automatically regulated continuous decompression. OSHA 
decompression requirements of 29 CFR 1926.803, which specify the use of 
automatically regulated continuous decompression (see footnotes 5 
through 10 below for references to these studies).\2\ In addition, the 
applicant asserts that staged decompression administered in accordance 
with the project-specific HOM is at least as effective as an automatic 
controller in regulating the decompression process the HOM includes for 
at least two reasons:
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    \2\ In the study cited in footnote 6, starting at page 338, Dr. 
Eric 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, who recommended using staged decompression. Dr. Kindwall then 
states, ``Continuous decompression is inefficient and wasteful. For 
example, if the last stage from 4 psig . . . to the surface took 1 
h, at least half the time is spent at pressures less than 2 psig . . 
., which provides less and less meaningful bubble suppression . . . 
.'' In addition, the report referenced in footnote 5 under the 
section titled ``Background on the Need for Interim Decompression 
Tables'' 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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    (1) A hyperbaric supervisor (a competent person experienced and

trained in hyperbaric operations, procedures, and safety) 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; and
    (2) The use of the 1992 French Decompression Tables for staged 
decompression offers an equal or better level of management and control 
over the decompression process than an automatic controller and results 
in lower occurrences of DCI.

C. 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 when total 
decompression time exceeds 75 minutes (29 CFR 1926.803(g)(1)(xvii)). 
Another provision of OSHA's compressed-air standard calls for locating 
the special decompression chamber adjacent to the man lock on the 
atmospheric pressure side of the tunnel bulkhead (29 CFR 
1926.803(g)(2)(vii)). However, since only the working chamber of the 
EPBMTBM is under pressure, and 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) are of sufficient 
size to accommodate the exposed workers. In addition, available space 
in the EPBMTBM does not allow for an additional special decompression 
lock. Again, the applicant uses the 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. This alternative 
enables CAWs to move about and flex their joints to prevent 
neuromuscular problems during decompression.

V. Decision

    After reviewing the proposed alternatives OSHA determined that:
    (1) Salini developed, and proposed to implement, effective 
alternative measures to the prohibition of using compressed air under 
hyperbaric conditions exceeding 50 p.s.i.g. The alternative measures 
include use of engineering and administrative controls of the hazards 
associated with work performed in compressed-air conditions up to 50 
p.s.i.g. while engaged in the construction of a subaqueous tunnel using 
advanced shielded mechanical-excavation techniques in conjunction with 
an EPBMTBM. Prior to conducting interventions in the EPBMTBM's 
pressurized working chamber, the applicant 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.
    (2) Salini developed, and proposed to implement, safe hyperbaric 
work procedures, emergency and contingency procedures, and medical 
examinations for the project's CAWs. The applicant compiled these 
standard operating procedures into a project-specific HOM. The HOM 
discusses 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. 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.
    (3) Salini developed, and proposed to implement, a training program 
to instruct affected workers in the hazards associated with conducting 
hyperbaric operations.
    (4) Salini developed, and proposed to implement, an effective 
alternative to the use of automatic controllers that continuously 
decrease pressure to achieve decompression in accordance with the 
tables specified by the standard. The 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.
    (5) Salini developed, and proposed to implement, an effective 
alternative to the use of the special decompression chamber required by 
the standard. EPBMTBM technology permits the tunnel's work areas to be 
at atmospheric pressure, with only the face of the EPBMTBM (i.e., the 
working chamber) at elevated pressure. The applicant limits 
interventions conducted in the working chamber to performing required 
inspection, maintenance, and repair of the cutting tools on the face of 
the EPBMTBM. The EPBMTBM's man lock and working chamber 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, OSHA determined that the EPBMTBM's man lock and 
working chamber function as effectively as the special decompression 
chamber required by the standard.
    OSHA conducted a review of the scientific literature regarding 
decompression to determine whether the alternative decompression method 
(i.e., the 1992 French Decompression Tables) proposed by the applicant 
provide a workplace as safe and healthful as that provided by the 
standard. Based on this review, OSHA determined that tunneling 
operations performed with these tables \3\ result in a lower occurrence 
of DCI than the decompression tables specified by the 
standard.4 5 6
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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).
    \4\ Kindwall, E.P. (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.
    \5\ Sealey, J.L. (1969). Safe exit from the hyperbaric 
environment: medical experience with pressurized tunnel operations. 
Journal of Occupational Medicine, 11(5), pp. 273-275. This article 
reported 210 treated cases of DCI among 38,600 hyperbaric exposures 
between 13 and 34 p.s.i.g. over a 32-month period, for an incidence 
of 0.54% for the decompression tables specified by the Washington 
State safety standards for compressed-air work, which are similar to 
the tables in the OSHA standard. Moreover, the article reported 51 
treated cases of DCI for 3,000 exposures between 30 and 34 p.s.i.g., 
for an incidence of 1.7% for the Washington State tables.
    \6\ In 1985, the National Institute for Occupational Safety and 
Health (NIOSH) published a report entitled ``Criteria for Interim 
Decompression Tables for Caisson and Tunnel Workers''; this report 
reviewed studies of DCI and other hyperbaric-related injuries 
resulting from use of OSHA's tables. This report is available on 
NIOSH's website: http://www.cdc.gov/niosh/topics/decompression/default.html.

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    The review conducted by OSHA found several research studies 
supporting the determination that the 1992 French Decompression Tables 
result in a lower rate of DCI than 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); \7\ this project used the 1992 French Decompression Tables to 
decompress the workers during part of the construction. Anderson 
observed 6 DCS cases out of 7,220 decompression events, and reported 
that switching to the 1992 French Decompression tables reduced the DCI 
incidence to 0.08%. 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. 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, nor did OSHA find any studies indicating that the 
1992 French Decompression Tables were more hazardous to employees than 
the OSHA decompression tables.\8\
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    \7\ Anderson H.L. (2002). Decompression sickness during 
construction of the Great Belt tunnel, Denmark. Undersea and 
Hyperbaric Medicine, 29(3), pp. 172-188.
    \8\ Le P[eacute]chon J.C., Barre P., Baud J.P., 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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    Based on a review of available evidence, the experience of State 
Plans 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, 
and the information provided in the applicant's variance application, 
OSHA is granting the permanent variance.
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    \9\ These state variances are available in the docket: Exs. 
OSHA-2012-0035-0006 (Nevada), OSHA-2012-0035-0007 (Oregon), and 
OSHA-2012-0035-0008 (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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    Under 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 finds that when the employer complies with the conditions of the 
following order, the working conditions of the employer's workers are 
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. Therefore, Salini must: (1) Comply 
with the conditions listed below under ``Conditions Specified for the 
Permanent Variance'' for the period between the date of this notice and 
completion of the Northeast Boundary Tunnel Project; (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 conditions, including the affected employees of other 
employers, using the same means it used to inform these employees of 
the application for a permanent variance. Additionally, this order will 
remain in effect until one of the following conditions occurs: (1) 
Completion of the Northeast Boundary Tunnel Project; or (2) OSHA 
modifies or revokes this final order in accordance with 29 CFR 1905.13.

VI. Description of the Conditions Specified for the Permanent Variance

    The conditions for the variance are set out in the Order at the end 
of this document. This section provides additional detail regarding the 
conditions in the Order.

Condition A: Scope

    The scope of the permanent variance limits coverage to the work 
situations specified under this condition. Clearly defining the scope 
of the permanent variance provides Salini, their employees, potential 
future applicants, other stakeholders, the public and OSHA with 
necessary information regarding the work situations in which the 
permanent variance applies. To the extent that Salini exceeds the 
defined scope of this variance, it will be required to comply with 
OSHA's standards.

Condition B: List of Abbreviations

    Condition C defines a number of abbreviations used in the permanent 
variance. OSHA believes that defining these abbreviations serves to 
clarify and standardize their usage, thereby enhancing the applicant's 
and their employees' understanding of the conditions specified by the 
permanent variance.

Condition C: Definitions

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

Condition D: Safety and Health Practices

    This condition requires the applicant to develop and submit to OSHA 
an HOM specific to the Northeast Boundary Tunnel at least six months 
before using the EPBMTBM, proof that the EPMBTBM's hyberbaric chambers 
have been designed, fabricated, inspected, tested marked, and stamped 
in accordance with the requirements for 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 Salini has already 
completed, enables OSHA to determine that the specific safety and 
health instructions and measures it specifies are appropriate to the 
field conditions of the tunnel (including expected geological 
conditions), conform to the conditions of the variance, and adequately 
protect the safety and health of the CAWs. It also facilitates OSHA's 
ability to ensure that the applicant is complying with these 
instructions and measures. The requirement for proof of compliance with 
ASME PVHO-1.2019 is intended to ensure that the equipment is 
structurally sound and capable of performing to protect the safety of 
the employees exposed to hyperbaric pressure.
    Additionally, the condition includes a series of related hazard 
prevention and control requirements and methods (e.g., decompression 
tables, job hazard analysis (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.

Condition E: Communication

    Condition E requires the applicant to develop and implement an 
effective system of information sharing and communication. Effective 
information

sharing and communication ensures 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 
condition also requires Salini 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 enables affected 
workers and support personnel to respond quickly and effectively to 
hazardous conditions or emergencies that may develop during EPBMTBM 
operations.

Condition F: Worker Qualification and Training

    This condition requires the applicant to develop and implement an 
effective qualification and training program for affected workers. The 
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 ensures 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 condition also requires the applicant to 
provide affected workers with information they can use to contact the 
appropriate healthcare professionals if they 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.

Condition G: Inspections, Tests, and Accident Prevention

    Condition G 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 helps to ensure the safe operation and physical 
integrity of the equipment and work areas necessary to conduct 
hyperbaric operations. The condition also enhances worker safety by 
reducing the risk of hyperbaric-related emergencies.
    Paragraph (3) of this condition requires the applicant to document 
tests, inspections, corrective actions, and repairs involving the 
EPBMTBM, and maintain these documents at the job site for the duration 
of the job. This requirement provides 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.

Condition H: Compression and Decompression

    This condition requires the applicant to consult with a 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 provision 
ensures 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 have an opportunity to acclimate prior to exposure to these 
hyperbaric conditions. OSHA believes this condition will prevent or 
reduce adverse reactions among CAWs to the effects of compression or 
decompression associated with the intervention work they perform in the 
EPBMTBM.

Condition I: Recordkeeping

    Condition I requires the applicant to maintain records of specific 
factors associated with each hyperbaric intervention. Under OSHA's 
existing recordkeeping requirements in 29 CFR 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 1904) resulting from exposure of an employee to hyperbaric 
conditions by completing the OSHA's Form 301 Injury and Illness 
Incident Report and OSHA's Form 300 Log of Work-Related Injuries and 
Illnesses. Salini did not seek a variance from this rule and therefore 
must comply fully with those requirements.
    Condition I adds additional reporting responsibilities, beyond 
those already required by the OSHA rule. Salini is 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 Condition J 
(using OSHA's 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), enables the Salini and OSHA to 
assess the effectiveness of the Permanent Variance in preventing DCI 
and other hyperbaric-related effects.

Condition J: Notifications

    Under this condition, Salini must, within specified periods, notify 
OSHA and local authorities of any recordable injuries, illnesses, or 
fatalities that occur as a result of hyperbaric exposures during 
EPBMTBM operations.
    These notification requirements enable the applicant, their 
employees, and OSHA to determine the effectiveness of the permanent 
variance in providing the requisite level of safety to the applicant's 
workers and, based on this determination, whether to revise or revoke 
the conditions of the permanent variance. Timely notification permits 
OSHA to take whatever action may be necessary and appropriate to 
prevent 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 condition also requires the applicant to notify 
OSHA if it ceases to do business, has a new address or location for 
their main office, or transfers the operations covered by the 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 permanent 
variance, and expedite the agency's administration and enforcement of 
the permanent variance. Stipulating that an applicant must 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 permanent variance, thereby ensuring 
the safety of workers involved in performing the operations covered by 
the permanent variance.

VII. Order

    As of the effective date of this final order, OSHA is revoking the 
interim order granted to the employer on August 27, 2019, and replacing 
it with a

permanent variance order. Note that there are not any substantive 
changes in the conditions between interim order and the final order.
    OSHA issues this final order authorizing Salini to comply with the 
following conditions instead of complying with the requirements of 
paragraphs 29 CFR 1926.803(e)(5), (f)(1), (g)(1)(iii), and 
(g)(1)(xvii). These conditions are:

A. Scope

    1. The permanent variance applies only to work:
    (a) That occurs in conjunction with construction of the Northeast 
Boundary Tunnel Project in Washington, DC, a subaqueous tunnel 
constructed using advanced shielded mechanical-excavation techniques 
and involving operation of an EPBMTBM;
    (b) 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.
    2. The permanent variance applies only when Salini stops the 
tunnel-boring work, pressurizes the working chamber, and the CAWs 
either enter the working chamber to perform interventions (i.e., 
inspect, maintain, or repair the mechanical-excavation components), or 
exit the working chamber after performing interventions.
    3. Except for the requirements specified by 29 CFR 1926.803(f)(1), 
(g)(1)(iii), and (g)(1)(xvii), Salini must comply fully with all other 
applicable provisions of 29 CFR part 1926.
    4. This order will remain in effect until one of the following 
conditions occurs:
    (1) Completion of the Northeast Boundary Tunnel Project; or (2) 
OSHA modifies or revokes this final order in accordance with 29 CFR 
1905.13.

B. List of Abbreviations

    Abbreviations used throughout this permanent variance include the 
following:

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

C. Definitions

    The following definitions apply to this permanent variance. These 
definitions 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 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 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 up to 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.\11\
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    \11\ Adapted from 29 CFR 1926.32(f).
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    5. Decompression illness (also called decompression sickness or the 
bends)--an illness 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 
sight 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).\12\
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    \12\ See Appendix 10 of ``A Guide to the Work in Compressed Air 
Regulations 1996,'' published by the United Kingdom Health and 
Safety Executive and 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 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. Earth Pressure Balanced Moving Tunnel Boring Machine--the 
machinery used to excavate the tunnel.
    7. Hot work--any activity performed in a hazardous location that 
may introduce an ignition source into a potentially flammable 
atmosphere.\13\
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    \13\ Also see 29 CFR 1910.146(b).
---------------------------------------------------------------------------

    8. Hyperbaric--at a higher pressure than atmospheric pressure.
    9. 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.
    10. Hyperbaric Operations Manual--a detailed, project-specific 
health and safety plan developed and implemented by the employer for 
working in compressed air during the Northeast Boundary Tunnel.
    11. Job hazard analysis--an evaluation of tasks or operations to 
identify potential hazards and to determine the necessary controls.
    12. 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.
    13. Pressure--a force acting on a unit area; usually expressed as 
pounds per square inch (p.s.i.).
    14. p.s.i.--pounds per square inch, a common unit of measurement of 
pressure; a pressure given in p.s.i. corresponds to absolute pressure.
    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. 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. Subtracting 14.7 from a pressure expressed in 
units of p.s.i.a. yields the gauge pressure, expressed as p.s.i.g.
    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.\14\
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    \14\ 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.

D. Safety and Health Practices

    1. Salini must implement the most recent project-specific HOM 
previously submitted to OSHA on February 1, 2018. The HOM shall provide 
the governing safety and health requirements regarding hyperbaric 
exposures during the tunnel-construction project.
    2. Salini must 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.
    3. Salini must use air as the only breathing gas in the working 
chamber.
    4. Salini must use the 1992 French Decompression Tables for air, 
air-oxygen, and oxygen decompression specified in the HOM, specifically 
the tables titled ``French Regulation Air Standard Tables.''
    5. Salini must equip man-locks used by their employees with an 
oxygen-delivery system as specified by the HOM. Salini must not store 
oxygen or other compressed gases used in conjunction with hyperbaric 
work in the tunnel.
    6. Workers performing hot work under hyperbaric conditions must use 
flame-retardant personal protective equipment and clothing.
    7. In hyperbaric work areas, Salini must maintain an adequate fire-
suppression system approved for hyperbaric work areas.
    8. Salini must develop and implement one or more JHAs for work in 
the hyperbaric work areas, and review, periodically and as necessary 
(e.g., after making changes to a planned intervention that affects 
their operation), the contents of the JHAs with affected employees. The 
JHAs must include all the job functions that the risk assessment \15\ 
indicates are essential to prevent injury or illness.
---------------------------------------------------------------------------

    \15\ See ANSI/AIHA Z10-2012, American National Standard for 
Occupational Health and Safety Management Systems, for reference.
---------------------------------------------------------------------------

    9. Salini must develop a set of checklists to guide compressed-air 
work and ensure that employees follow the procedures required by this 
permanent variance (including all procedures required by the HOM, which 
this permanent variance incorporates by reference). The checklists must 
include all steps and equipment functions that the risk assessment 
indicates are essential to prevent injury or illness during compressed-
air work.
    10. Salini must ensure that the safety and health provisions of the 
HOM adequately protect the workers of all contractors and 
subcontractors involved in hyperbaric operations.\16\
---------------------------------------------------------------------------

    \16\ See ANSI/ASSE A10.33-2011, American National Standard for 
Construction and Demolition Operations--Safety and Health Program 
Requirements for Multi-Employer Projects, for reference.
---------------------------------------------------------------------------

E. Communication

    1. Prior to beginning a shift, Salini must 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. Salini must provide a power-assisted means of communication 
among affected workers and support personnel in hyperbaric conditions 
where unassisted voice communication is inadequate.
    a. Salini must use an independent power supply for powered 
communication systems, and these systems must 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. Salini must test communication systems at the start of each 
shift and as necessary thereafter to ensure proper operation.

F. Worker Qualification and Training

    Salini must:
    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, before beginning hyperbaric 
operations, to each worker who performs work, or controls the exposure 
of others, in hyperbaric conditions, and document this instruction. The 
instruction must include topics such as:
    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; 
and
    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.
    3. Repeat the instruction specified in paragraph (2) of this 
condition periodically and as necessary (e.g., after making changes to 
their hyperbaric operations).
    4. When conducting training for their hyperbaric workers, make this 
training available to OSHA personnel and notify OTPCA the BWAO before 
the training takes place.

G. Inspections, Tests, and Accident Prevention

    1. Salini must 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) by:
    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, 
as well as weekly inspections of the EPBMTBM.
    2. If the competent person determines that the equipment 
constitutes a safety hazard, Salini must remove the equipment from 
service until it corrects the hazardous condition and has the 
correction approved by a qualified person.
    3. Salini must 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.

H. Compression and Decompression

    Salini must consult with their attending physician concerning the 
need for special compression or decompression exposures appropriate for 
CAWs not acclimated to hyperbaric exposure.

I. Recordkeeping

    Salini must maintain a record of any recordable injury, illness, or 
fatality (as defined by 29 CFR part 1904 Recording and Reporting 
Occupational Injuries and Illnesses) resulting from exposure of an 
employee to hyperbaric conditions by completing the OSHA's Form 301

Injury and Illness Incident Report form and OSHA's Form 300 Log of 
Work-Related Injuries and Illnesses.
    Examples of important information to include on the OSHA's 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.\17\
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    \17\ 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).
---------------------------------------------------------------------------

    In addition to completing the OSHA's Form 301 Injury and Illness 
Incident Report form and OSHA's Form 300 Log of Work-Related Injuries 
and Illnesses, the employer must maintain records of:
    1. The date, times (e.g., began compression, time spent 
compressing, time performing intervention, time spent decompressing), 
and pressure for each hyperbaric intervention.
    2. The name of each individual worker exposed to hyperbaric 
pressure and the decompression protocols and results for each worker.
    3. The total number of interventions and the total hyperbaric 
exposure duration at each pressure.
    4. 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 or mixed gases for each hyperbaric 
intervention.

J. Notifications

    1. To assist OSHA in administering the conditions specified herein, 
the employer must:
    a. Notify the OTPCA and the Baltimore/Washington OSHA Area Office 
of any recordable injury, illness, or fatality (by submitting the 
completed OSHA's Form 301 Injury and Illness Incident Report form \18\) 
resulting from exposure of an employee to hyperbaric conditions, 
including those exposures 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 employer 
shall provide the notification within 8 hours of the incident or 8 
hours after becoming aware of a recordable injury, illness, or 
fatality, and submit a copy of the incident investigation (OSHA's Form 
301 Injury and Illness Injury Reporting Form) 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 the 
OSHA's Form 301 Injury and Illness Injury Reporting Form, the incident-
investigation report must include a root-cause determination, and the 
preventive and corrective actions identified and implemented.
---------------------------------------------------------------------------

    \18\ See footnote 4.
---------------------------------------------------------------------------

    b. Provide certification within 15 days of the incident that the 
employer 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 Baltimore/Washington OSHA Area Office 
within 15 working days in writing of any change in the compressed-air 
operations that affects the employer's ability to comply with the 
conditions specified herein.
    d. Upon completion of the Northeast Boundary Tunnel, evaluate the 
effectiveness of the decompression tables used throughout the project, 
and provide a written report of this evaluation to the OTPCA and the 
Baltimore/Washington OSHA Area Office.

    Note: The evaluation report is 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's Form 301 Injury and Illness Incident Report and OSHA's 
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 conditions specified herein, 
inform the OTPCA and the Baltimore/Washington OSHA Area Office as soon 
as possible after it has knowledge that it will:
    i. Cease to do 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 permanent variance by the 
same means required to inform them of the application for a variance.
    g. This permanent variance cannot be transferred to a successor 
company without OSHA approval.

VIII. Authority and Signature

    Loren Sweatt, Principal Deputy Assistant Secretary of Labor for 
Occupational Safety and Health, 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 May 5, 2020.
Loren Sweatt,
Principal Deputy Assistant Secretary of Labor for Occupational Safety 
and Health.
[FR Doc. 2020-09967 Filed 5-8-20; 8:45 am]
 BILLING CODE 4510-26-P