 United States Court of Appeals
         FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued February 14, 2013                Decided June 7, 2013

                        No. 11-1464

            CUMBERLAND COAL RESOURCES, LP,
                     PETITIONER

                              v.

 FEDERAL MINE SAFETY AND HEALTH REVIEW COMMISSION
              AND SECRETARY OF LABOR,
                   RESPONDENTS

            UNITED MINE WORKERS OF AMERICA,
                      INTERVENOR


        On Petition for Review of a Decision of the
    Federal Mine Safety and Health Review Commission


    Ralph Henry Moore II argued the cause for petitioner. With
him on the briefs was Patrick W. Dennison.

    Robin A. Rosenbluth, Senior Attorney, U.S. Department of
Labor, argued the cause for respondent. With him on the brief
were W. Christian Schumann, Counsel. John T. Sullivan,
Attorney, Mine Safety and Health Review Commission, entered
an appearance.

     Judith Rivlin and Arthur Traynor were on the brief for
intervenor United Mine Workers of America in support of
                                2

respondent.

    Before: ROGERS and TATEL, Circuit Judges, and SENTELLE,
Senior Circuit Judge.

   Opinion for the Court filed by Senior Circuit Judge
SENTELLE.

      SENTELLE, Senior Circuit Judge: This case comes before
us on a petition for review of the Federal Mine Safety and
Health Review Commission’s determination that Cumberland
Coal Resources, LP’s failure to maintain adequate emergency
lifelines in its mine’s escapeways was a significant and
substantial violation of the Federal Mine Safety and Health Act
of 1977 (“Mine Act”), 30 U.S.C. § 814(d)(1). Cumberland
argues that the Commission applied the wrong standard when it
reversed an administrative law judge’s (“ALJ’s”) determination
that the violations were not significant and substantial, and that
even if it applied the correct standard, its findings are not
supported by substantial evidence. Because we conclude that
the Commission applied the correct standard and that substantial
evidence supported its findings, we deny Cumberland’s petition
for review.

                     I. BACKGROUND

    A. Statutory and Regulatory Background

     In 1977, Congress enacted the Federal Mine Safety and
Health Act for the purpose of improving the working conditions
of miners. 30 U.S.C. § 801. Under the Act, inspectors from the
Mine Safety and Health Administration (“MSHA”), acting on
behalf of the Secretary of Labor, conduct regular compliance
inspections of mines. 30 U.S.C. § 813(a). When an inspector
believes that the operator of a mine has violated the Act or
                                3

enforceable regulations promulgated pursuant to the Act, the
inspector is authorized to issue citations for such violations and,
in appropriate cases, to issue orders to withdraw personnel from
the mine until “such violation has been abated.” 30 U.S.C.
§ 814(b). Section 814(d)(1) provides that if the authorized
representative of the Secretary finds that there has been a
violation of a mandatory health or safety standard and also finds
that the violation “is of such nature as could significantly and
substantially contribute to the cause and effect of a coal or other
mine safety or health hazard,” then the inspector is to include
that finding in the citation issued for the violation. Such a
finding of a significant and substantial violation (often referred
to as an “S&S violation”) is a precondition for enhanced
enforcement actions under the Mine Safety Act. See 30 U.S.C.
§ 814(d) (discussed and applied in RAG Cumberland Resources
LP v. FMSHRC, 272 F.3d 590, 592–93 (D.C. Cir. 2001)).

     The violations at issue in this case arose under amendments
to the Mine Safety and Health Act enacted in response to three
multiple-fatality mine disasters, in which miners who were
unable to evacuate mines died. Specifically, the Mine
Improvement and New Emergency Response Act of 2006
(“MINER Act”), amended 30 U.S.C. § 876 to require operators
to provide flame resistant and directional lifelines in escapeways
“to enable evacuation.” MINER Act Section 2(3)(b)(E)(iv),
Pub. L. No. 109-236 (S. 2803) (June 15, 2006), codified at 30
U.S.C. § 876(b)(2)(E)(iv). Also in the wake of the disasters,
MSHA issued an Emergency Temporary Standard on emergency
mine evacuations in March 2006. 71 Fed. Reg. 12252 (Mar. 9,
2006). This standard became a final rule on December 8, 2006.
71 Fed. Reg. 71430 (Dec. 8, 2006). That rule requires operators
to provide each mine escapeway with a lifeline that is “[l]ocated
in such a manner for miners to use effectively to escape.” 30
C.F.R. § 75.380(d)(7)(iv). Each lifeline must be equipped with
directional indicators showing the route of escape, indicators
                                 4

marking a branch line that is attached to the lifeline and leads to
a cache of stored self-contained self-rescuers providing
breathable air for emergencies, and indicators marking a branch
line attached to the lifeline and leading to a refuge alternative for
miners unable to escape. 30 C.F.R. § 75.30(d)(7)(v), (vii).

      In December 2007, obedient to the statutory requirement
that the Secretary or his representative conduct frequent
inspections of mines to ensure compliance with mandatory
safety standards, Thomas J. Whitehair II, Special Investigator
for the Department of Labor’s Mine Safety and Health
Administration, conducted an inspection of the Cumberland
Mine near Waynesburg, Pennsylvania. Whitehair inspected four
of the mine’s escapeways over a four-day period and issued a
citation for each, alleging violation of the lifeline requirement of
§ 75.380(d)(7)(iv). He further designated each violation as
significant and substantial, finding that the lack of adequate
lifelines would have delayed miners escaping from an
emergency, which would have been reasonably likely to result
in serious injury or death.

    B. The Administrative Proceedings

      On April 11, 2008, the Secretary filed a petition for
assessment of civil penalty for the violations. Cumberland
contested the citations before an administrative law judge, who
deleted the significant and substantial designations on January
21, 2011. See 33 FMSHRC 1482. Thereafter, the Commission
heard the petition for review and granted the petition. The
Commission reversed and remanded to the ALJ for the
imposition of penalties. On October 25, 2011, the ALJ issued
a decision on remand imposing penalties. After the Commission
denied Cumberland’s petition for discretionary review,
Cumberland filed the present petition for review with this court
on November 29, 2011.
                                 5

     Because our review is dependent in part on the sufficiency
of the evidence in the administrative proceedings, we will set
forth the relevant evidence in some detail, as well as make
further references to the record in our analysis. The evidence
was presented in the testimony of Inspector Whitehair relating
his findings and conclusions in the four-day visit to the mine in
December 2007. Whitehair first testified as to his experience in
mining and mine safety. According to that testimony, he had
twenty-two years experience inspecting mines for MSHA and an
additional fourteen years experience working in mines,
including in mine safety positions. He then testified as to his
findings of violations at the Cumberland Mine.

         1. The Violations

              a. The December 6, 2007, Violation

        Whitehair testified that he inspected the No. 1 belt entry
of the Five Butt East Longwall section on December 6, 2007.
He found three violations in the provision of that lifeline which
would have delayed miners in escaping in the event of an
emergency. First, it was hung so high from the mine floor that
it would have been difficult or impossible for many miners to
reach. Second, it was suspended from J-hooks that pointed in
different directions. And third, cables and waterlines ran
underneath and perpendicular to it.

         Whitehair further testified that these conditions would
have delayed miners in escaping from an emergency. First,
because many would have found the lifeline out of reach, they
would have needed to use a tool to access it. Second, miners
would have been forced to use that tool to flip the lifeline off the
J-hooks, which were pointed in all directions—a task Whitehair
testified “would take considerable doing and a considerable
amount of time.” Third, once off the hooks, the lifeline would
                               6

fall on top of the water lines and cables that ran underneath and
perpendicular to it, requiring miners to release the lifeline and
search for it on the other side of the cables and waterlines.

      Whitehair further testified that this delay would have been
reasonably likely to result in injury. He believed that in the
event of an emergency during which miners would need a
lifeline, they would not be able to escape and would eventually
succumb to carbon monoxide poisoning. The ALJ credited that
testimony.

             b. The December 7, 2007, December 10, 2007,
             and December 11, 2007, Violations

         The evidence is similar with respect to the other three
violations. Whitehair testified that on December 7, 2007, the
lifeline in the No. 2 track entry for the Five Butt East Longwall
hung out of reach for many miners throughout most of the track
entry. He also observed track equipment, cables, and waterlines
under the lifeline.

        Whitehair testified that on December 10, 2007, he
observed that the lifeline in the No. 2 track entry of the Eight
Butt East section was hung high and out of reach for many
miners throughout most of the track entry. He also observed
track equipment, cables, and waterlines under the lifeline.

         On December 11, 2007, Whitehair found nearly the
entire lifeline in the No. 2 track entry of the Fifteen Butt East
section hung high and out of reach for many miners. He also
testified that it was suspended over track equipment.

      Whitehair testified that the track equipment under the
lifeline would delay miners attempting to escape an emergency.
In thick smoke, the lead miner would be blinded and would run
                                7

into the track equipment. That could injure him or rupture his
self-contained self-rescuer—the portable oxygen source
providing breathable air that each miner should have during an
emergency—exposing him to deadly smoke. Even if the lead
miner was unscathed, running into track equipment would delay
all the miners attempting to escape. Furthermore, Whitehair
testified that the lifeline could snag on the track equipment,
causing further delays as panicked, blinded miners attempted to
free it. Even if miners knew the track equipment was in their
path, they would have to proceed more slowly than they
otherwise would to avoid it in the smoky darkness, which would
delay their escape. Whitehair also testified that the lifelines
falling on cables and waterlines would delay miners escaping.
As he had with the first violation, Whitehair testified that he
designated these three violations significant and substantial
because the delays he described would be reasonably likely to
make it impossible for a miner to escape an emergency, meaning
the miner would eventually succumb to carbon monoxide
poisoning.

    In short, based on his other findings, Whitehair found that
each of the four violations was significant and substantial.

    C. The Administrative Decisions

     As noted above, the administrative law judge, while
crediting and adopting the inspector’s underlying findings,
rejected the findings of significant and substantial violations. 31
FMSHRC at 1163–64. The Commission then reversed the ALJ
on the significant-and-substantial issue in the decision that we
review today.

    The ALJ and the Commission differ over an issue of basic
understanding of the statutory and regulatory requirements for
determining the significant and substantial status of a violation.
                                8

As the Commission states in its brief to us, “the issue [is]
whether, in evaluating whether a violation of Section
75.380(d)(7)(iv)’s requirement regarding the location of lifelines
‘is of such nature as could significantly and substantially
contribute to the cause and effect of a coal or other mine safety
or health hazard’ within the meaning of Section 104(d)(1) of the
Mine Act, 30 U.S.C. § 814(d)(1), one should assume the
occurrence of an emergency necessitating an evacuation in
which the lifeline would need to be used.” Respondent’s Br.
22–23. The answer to this question is essential to the decision
of the case and any other case involving violations of statutory
and safety regulations created to protect miners and reduce
danger during evacuations.

     The ALJ adopted a view that Whitehair and the
Commission acted inconsistently with Commission precedent in
determining that the violations were significant and substantial.
The ALJ relied in making that determination, and Cumberland
relies before us, on language from Secretary of Labor v. Mathies
Coal Co., 6 FMSHRC 1, 3–4 (1984), to the effect that in order
to prove a significant and substantial violation the Secretary
must prove:

    (1) [T]he underlying violation of a mandatory safety
    standard; (2) a discrete safety hazard—that is, a measure of
    danger to safety—contributed to by the violation; (3) a
    reasonable likelihood that the hazard contributed to will
    result in an injury; and (4) a reasonable likelihood that the
    injury in question will be of a reasonably serious nature.

     The ALJ ruled that the Secretary had failed to establish the
third element of the Mathies test—a reasonable likelihood that
the hazard contributed to by the violations would result in an
injury. 31 FMSHRC at 1163. According to the ALJ, the
Secretary had failed to prove that there was a reasonable
                                9

likelihood that an emergency situation would arise, and
therefore it was not reasonably likely that the hazard contributed
to—miners being delayed in escaping from an
emergency—would result in an injury.

     The Commission unanimously reversed the ALJ and held
that all four lifeline standard violations were significant and
substantial. The Commission interpreted the statute and
regulation to require assessment of the reasonable likelihood of
injury in the circumstance in which the safety equipment
becomes relevant. That is, evacuation standards, such as those
before the Commission and now before us, “apply meaningfully
only when an emergency actually occurs.” 33 FMSHRC at
2367. After the ALJ on remand increased the penalties for each
violation to account for the significant and substantial findings,
Cumberland filed this petition.

                        II. ANALYSIS

     While Cumberland in its brief before us alleges five issues,
our review neatly falls into two parts: (1) did the Commission
properly interpret the statutory and regulatory requirement of
significant and substantial violation for enhanced penalties?; and
(2) if the Commission applied the correct standard, was there
sufficient evidence to support the Commission’s decision? We
discuss those two issues in turn.

    A. The Significant and Substantial Standard

        The Mine Act requires the Commission to adjudicate
challenges by mine operators to citations and orders issued by
the Secretary. See 30 U.S.C. § 813. The Commission must
defer to “the Secretary’s interpretations of the law and
regulations.” Sec’y of Labor v. Cannelton Indus., Inc., 867 F.2d
1432, 1435 (D.C. Cir. 1989) (internal quotation marks omitted).
                                10

On review, this court must defer to the Secretary’s reasonable
interpretations of the language of the Mine Act. Id. (citing
Chevron U.S.A., Inc. v. Natural Res. Def. Council, Inc., 467 U.S.
837 (1984)). “[I]n the statutory scheme of the Mine Act, the
Secretary’s litigating position before the Commission is as much
an exercise of delegated lawmaking powers as is the Secretary’s
promulgation of a . . . health and safety standard, and is
therefore deserving of deference.” Sec’y of Labor v. Excel
Mining, LLC, 334 F.3d 1, 6 (D.C. Cir. 2003) (internal quotation
marks omitted). Where, as here, the Secretary and the
Commission agree, there is no question but that we must accord
deference to their joint view. RAG Cumberland Res. LP v.
FMSHRC, 272 F.3d 590, 596 (D.C. Cir. 2001).

        We analyze the Secretary’s and the Commission’s
interpretations of the Mine Act under the Chevron framework.
Id. Under that familiar standard, “this court, of course, must
give effect to the unambiguously expressed intent of Congress.”
Cannelton Indus., Inc., 867 F.2d at 1435 (internal quotation
marks omitted). If “the statute is silent or ambiguous with
respect to the specific issue,” the court defers to the Secretary’s
interpretation provided the interpretation is “‘a permissible
construction of the statute.’” Id. (quoting Chevron, 467 U.S. at
843).

        30 U.S.C. § 814(d)(1) provides that a significant and
substantial violation is one that is “of such nature as could
significantly and substantially contribute to the cause and effect
of a coal or other mine safety or health hazard.” We first
consider the Secretary’s argument that this language
unambiguously expresses Congress’s intent to require
decisionmakers evaluating the significant and substantial nature
of violations of emergency safety standards such as
§ 75.380(d)(7)(iv) to assume the existence of the contemplated
emergency.
                                 11

         The Secretary argues that Congress’s use of the words
“could” and “contribute” and the phrase “cause and effect” to
describe significant and substantial violations unambiguously
compels his interpretation. Specifically, the Secretary argues
that “it is impossible to determine whether the violations of
Section 75.380(d)(7)(iv) significantly and substantially
contributed to the cause and effect of the hazard in
question—miners being unable to escape quickly from a mine
during an emergency in which miners would need to use the
lifeline—without assuming the occurrence of such an
emergency.” Respondent’s Br. 27. The Secretary also argues
that the word “could” refers to the violation’s intrinsic capacity
to contribute to the hazard, not to any specific probability that it
will. Id. at 28 (quoting United States v. Peterson, 538 F.3d
1064, 1072 (9th Cir. 2008)). Although the Secretary does not
flesh this argument out, he appears to mean that because
intrinsic capacity is enough, a violation of an emergency safety
standard can be significant and substantial even if an emergency
is not likely.

     We do not think the Mine Act’s language unambiguously
compels the Secretary’s interpretation. The Secretary’s
argument that “could” refers to intrinsic capacity rather than
probability overlooks the fact that the statute refers to a violation
that could “significantly and substantially contribute to the cause
and effect of a . . . hazard.” 30 U.S.C. § 814(d)(1) (emphasis
added). Because the two adverbs inherently suppose a degree of
contributing, we cannot hold that the language unambiguously
excludes a probabilistic approach to the factfinder’s
determination that a particular violation falls within the ambit of
the statutory language. We therefore reject the Secretary’s
proposition that his interpretation can be upheld under the first
prong of Chevron.
                               12

     Perhaps in the evaluation of the possible significant and
substantial nature of a violation of general safety standards not
contemplating an emergency, the Secretary and the Commission
might focus exclusively on the propensity of the violation to
“contribute to the cause and effect” of a safety or health hazard.
But violations of emergency safety standards raise a different set
of problems. Those standards—and specifically, the standards
effectuating the MINER Act’s protection of escape—protect
specifically against hazards that may arise after an emergency
has already occurred. Despite that fact, inspections determining
the compliance of mine operators with the standard must be
made in the absence of the contemplated emergency. Therefore,
in the view of Cumberland and the ALJ, the Secretary should
weigh the probability variable independent of the violation, that
is, of the probability of a hazard arising in the first place. On
that issue, § 814(d)(1) is silent. We cannot, therefore, say that
the intent of Congress is clear and unambiguous so as to allow
the invocation of Chevron step one.

     It may be, as the Secretary argues, that the term “hazard” in
§ 814(d)(1) accounts for the probability of an emergency
occurring because the hazard in this case can only be stated in
terms that assume the existence of an emergency. But it may
also be, as Cumberland argues, that the phrase “could
significantly and substantially contribute,” which calls to mind
an evaluation of chance, properly accounts for all probability
variables in any given significant and substantial evaluation,
including the probability of an emergency occurring. We
therefore proceed to the second step of the Chevron analysis and
evaluate the reasonableness of the Secretary’s interpretation.

    Although the statute does not unambiguously compel the
Secretary’s interpretation, that interpretation is nonetheless
reasonable. As the Commission explained, emergency safety
standards are fundamentally different from non-emergency
                                13

standards because they are designed to apply meaningfully only
in times of emergency. If the Secretary interpreted, or if we
compelled the Secretary to interpret, § 814(d)(1) to command
decisionmakers not to assume the existence of the contemplated
emergency when evaluating the significant and substantial
nature of a violation of emergency safety standards, it would
appear unlikely that any violation of those standards would ever
be “significant and substantial.” That is, the violation of those
standards apparently would never, or at least rarely, contribute
to the existence of the emergency so that the scale would be
loaded against the finding. Given that the violation of those
standards could be expected to have serious, indeed tragic,
consequences, it is reasonable for the Secretary to interpret the
statute and his own regulations to avoid that odd result.

        To expand on that thought, the interpretation advanced
by Cumberland would be inconsistent with our prior holding
that the significant and substantial inquiry should focus, as the
statutory text directs, on the nature of the violation. Sec’y of
Labor v. FMSHRC, 111 F.3d 913, 917 (D.C. Cir. 1997). Again,
a violation of the lifeline standard could only contribute to the
delayed evacuation from emergency hazard if there is an
emergency, but the likelihood of an emergency will usually have
nothing to do with the violation of the emergency safety
standard. Thus, if the decisionmaker does not assume the
existence of the emergency, then his focus must necessarily shift
away from the nature of the violation to the likelihood of the
emergency.

        None of Cumberland’s arguments for rejecting the
Secretary’s interpretation is persuasive. First, Cumberland
argues that the Secretary’s interpretation is inconsistent with the
Commission’s Mathies test. As noted above, the Commission
held in Mathies that to demonstrate a significant and substantial
violation, the Secretary must prove four elements: (1) the
                                14

underlying violation of a mandatory safety standard; (2) a
discrete safety hazard—that is, a measure of danger to
safety—contributed to by the violation; (3) a reasonable
likelihood that the hazard in question will result in an injury; and
(4) a reasonable likelihood that the injury in question will be of
a reasonably serious nature. 6 FMSHRC at 3–4. Cumberland
argues that by assuming the existence of an emergency, the
Commission excused the Secretary from his burden of proving
the second and third elements of the Mathies test. The hazard
here is delayed escape from an emergency, but there can be no
delayed escape, unless there is an emergency in the first place.
Similarly, if there is no emergency, then there can be no
resulting injury.

        The problem with these arguments is that they assume
that the Mathies test forbids the decisionmaker from assuming
the existence of an emergency. It does not. Indeed, in the only
Commission precedent to have considered whether assuming the
existence of an emergency is consistent with the Mathies test,
the Commission split on the question, resulting in a non-
precedential opinion. See Sec’y of Labor v. Manalapan Mining,
18 FMSHRC 1375 (1996). Further, ALJs have routinely
assumed the occurrence of the contemplated emergency in
evaluating the significant and substantial nature of violations
that only come into play in the event of an emergency. See, e.g.,
Twentymile Coal Co., 29 FMSHRC 806, 810–11 (2007) (ALJ);
American Coal Co., 29 FMSHRC 252, 263 (2007) (ALJ), aff’d
on other grounds, 29 FMSHRC 941 (2007); Anderson Sand &
Gravel, 21 FMSHRC 186, 191 (1999) (ALJ). Therefore,
contrary to Cumberland’s argument, the Secretary’s argument
is not inconsistent with Mathies. In addressing this argument,
we do not intend to imply that we are adopting the Mathies test,
the validity of which is not challenged here. Instead, we simply
reject Cumberland’s argument that the Secretary’s interpretation
arbitrarily or capriciously departs from Commission precedent.
                               15


        Cumberland also argues that the Secretary’s
interpretation ignores Commission precedent by excusing the
Secretary from his duty to consider all of the facts surrounding
a violation. Petitioner’s Br. 33–34 (citing National Gypsum, 3
FMSHRC 822, 825 (1981)).            But we have held that
decisionmakers should not consider facts unrelated to the
violation when undertaking a significant and substantial
evaluation. Sec’y of Labor v. FMSHRC, 111 F.3d at 917. In this
case, the Secretary met the standard in our cases and the
National Gypsum standard by considering all of the facts
surrounding the violation.

        Finally, Cumberland argues that the Secretary’s
interpretation ignores Commission precedent rejecting an
interpretation of the statute by which all mine safety and health
standards would be significant and substantial except those that
had no potential to cause injury. National Gypsum, 3 FMSHRC
at 825. That general rule, which would apply to all violations,
differs from the narrower rule at issue here, which applies only
to violations of emergency safety measures. Because the stakes
are much higher in emergency situations, a rule that would make
many or most violations of emergency safety measures
significant and substantial is distinguishable from a rule that
would make all violations of all safety measures significant and
substantial. Moreover, the Secretary proposes a rule that would
require a reasonable likelihood of injury, whereas National
Gypsum rejected a broader rule that would have allowed a
significant and substantial finding anytime there was any
potential of injury, not just where injury was reasonably likely.
For these reasons, Cumberland’s argument fails.
                              16

       B. Substantial Evidence

       Cumberland next argues that even if the Commission
applied the correct significant and substantial standard, its
determination that the violations at issue here were significant
and substantial is not supported by substantial evidence. Under
the substantial evidence standard of review, we may not reject
reasonable findings and conclusions, even if we would have
weighed the evidence differently. Sec’y of Labor v. Keystone
Coal Mining Corp., 151 F.3d 1096, 1104 (D.C. Cir. 1998). We
must therefore examine Cumberland’s specific allegations and
“determine whether a theoretical ‘reasonable factfinder’ could
have reached the conclusions actually reached by the
Commission and the ALJ.” Id. (quoting United Steelworkers of
America v. NLRB, 983 F.2d 240, 244 (D.C. Cir. 1993)).
Applying this “highly deferential standard,” we conclude that
the Commission’s decision rests on substantial evidence. Sec’y
of Labor v. FMSHRC, 111 F.3d at 918.

        Cumberland argues that in finding that these violations
were significant and substantial, the Commission refused to
consider evidence of preventative measures that would have
rendered both injuries from an emergency and the occurrence of
an emergency in the first place less likely. Cumberland
contends that in doing so, the Commission failed to consider all
evidence including that which detracts from its position, and
thus, its conclusion fails the substantial evidence test. See
Universal Camera Corp. v. NLRB, 340 U.S. 474, 488 (1951);
American Wrecking Corp. v. Sec’y of Labor, 351 F.3d 1254,
1261 (D.C. Cir. 2003) (“The substantial evidence rule requires
that the Commission reasonably consider material evidence on
both sides, as evidence that is substantial when viewed in
isolation may become insubstantial when contradictory evidence
is taken into account.”).
                                 17

        The first problem with Cumberland’s argument is that
assuming the existence of an emergency in which a lifeline
would be necessary also assumes an emergency in which all of
the redundant safety measures Cumberland seeks to rely on have
failed. The second problem is that consideration of redundant
safety measures is inconsistent with the language of § 814(d)(1).
As we have explained, the focus of the significant and
substantial inquiry is the nature of the violation. “By focusing
the decisionmaker’s attention on ‘such violation’ and its
‘nature,’ Congress has plainly excluded consideration of
surrounding conditions that do not violate health and safety
standards.” Sec’y of Labor v. FMSHRC, 111 F.3d at 917.
Because redundant safety measures have nothing to do with the
violation, they are irrelevant to the significant and substantial
inquiry. Id.; see also Buck Creek Coal, Inc. v. FMSHA, 52 F.3d
133, 136 (7th Cir. 1995) (rejecting an argument that redundant
safety measures detracted from a significant and substantial
finding).

           Finally, Cumberland argues that the Commission’s
significant and substantial findings are not supported by
substantial evidence because “even assuming a hypothetical fire
. . . , the evidence shows that it is not reasonably likely that such
an event would result in a serious injury.” Petitioner’s Br. 46.
As the Secretary points out, this objection misapprehends how
the Mathies test applies. Under Mathies, the question is whether
the hazard contributed to is reasonably likely to result in serious
injury. 33 FMSHRC at 2366. Cumberland argues that
substantial evidence does not support the conclusion that a
hypothetical mine fire would be reasonably likely to result in
serious injury, but the hazard here is not a hypothetical mine
fire—it is delayed escape from one. Putting that aside, a review
of the record demonstrates that substantial evidence does in fact
support the Commission’s conclusions.
                                18

       Whitehair’s testimony, which the ALJ accepted,
provided a sufficient basis upon which a reasonable factfinder
could conclude that the lifeline violations at issue here would
delay miners from escaping from an emergency and that such a
delay would be reasonably likely to cause serious injuries or
death.

         With respect to the December 6 violation, the evidence
we set forth above in the discussion of the violations was
credited by the ALJ and constitutes substantial evidence that the
lifeline violation Whitehair identified in the No. 1 belt entry of
the Five Butt East Longwall section contributed to the hazard of
a miner being delayed or unable to escape during an emergency
and that the hazard was reasonably likely to result in serious
injury.

        Cumberland argues that in the event of a fire, miners
were unlikely to be hurt because they could use the belt structure
to guide them out of the mine and could use the waterline
running along the belt as a directional indicator. That argument
is unpersuasive. First, the record demonstrates that miners are
trained to use lifelines in emergencies, and thus, even if they did
think to use the belt structure or the waterlines, they would still
be delayed as they first attempted to find and use the lifeline.
Second, Whitehair testified that because the waterline and belt
structure lacked the lifeline’s required directional indicators, “it
would be very easy [for miners] to become confused and maybe
turn around and go the wrong direction, because it’s not going
to tell them what direction they are going.”                 Third,
Cumberland’s argument ignores another lifesaving advantage an
adequate lifeline would have over a cable or waterline: lifelines
are designed to guide miners to alternative refuges, and
waterlines and cables are not. Therefore, the Commission’s
findings were reasonable, and under the substantial evidence
                              19

standard of review, we must accept them. See Keystone Coal
Mining Corp., 151 F.3d at 1104.

       Again, without rehashing the evidence set forth above,
the same conclusion follows with respect to each of the other
three violations. The Commission’s decision rested on
substantial evidence. We therefore reject Cumberland’s
evidentiary objection and must deny its petition.

       While Cumberland advances other arguments, none
warrant further discussion.

                      CONCLUSION

       Because the Commission applied the correct significant
and substantial standard, and because substantial evidence
supports each of the significant and substantial determinations
in question, the petition for review is denied.

                                                   So ordered.
