234 F.3d 720 (D.C. Cir. 2000)
Montgomery KONE, Inc. Petitionerv.Secretary of Labor, Respondent
No. 00-1029
United States Court of Appeals FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued October 17, 2000Decided December 22, 2000

On Petition for Review of an Order of the Occupational Safety and Health Review Commission
W. Scott Railton argued the cause for petitioner.  With  him on the briefs was Paul J. Waters.
Jill M. Lashay was on the brief for amicus curiae National  Elevator Industry, Inc.
Lee Grabel, Attorney, U.S. Department of Labor, argued  the cause for respondent.  With him on the briefs were  Joseph M. Woodward, Associate Solicitor, and Bruce Justh,  Counsel.
Before:  Williams, Randolph and Tatel, Circuit Judges.
Tatel, Circuit Judge:


1
Following an explosion in an elevator pit, the Secretary of Labor fined petitioner for failing to  provide special training required by OSHA regulations for  workers who must enter "confined spaces."  Finding the  agency's interpretation of its own regulations reasonable and  its decision supported by substantial evidence, we affirm.


2
* Occupational Safety and Health Administration regulations  governing safety training in the construction industry provide  that workers required to enter "confined or enclosed spaces"  must receive special training "as to the nature of the hazards  involved, the necessary precautions to be taken, and in the  use of protective and emergency equipment."  29 C.F.R.  § 1926.21(b)(6)(i).  In language central to this case, the regulations define a confined space as "any space having limited  means of egress, which is subject to the accumulation of toxic  or flammable contaminants or has an oxygen deficient atmosphere."  29 C.F.R. § 1926.21(b)(6)(ii).


3
The space involved in this case is a pit at the base of an  elevator in a United States Post Office truck terminal in  Philadelphia.  Located beneath the elevator's floor line, the  pit is about four feet, ten inches deep and measures twelve  feet by sixteen to eighteen feet across.  During the period of  time involved in this case, the floor of the pit could only be  reached with ladders:  a permanent metal ladder was attached to one wall;  an orange extension ladder and a six-foot  fiberglass ladder leaned against two other walls;  and a  wooden A-frame ladder stood in the center.  Sec'y of Labor v.  Montgomery KONE, Inc., 1999 OSHRC No. 37 at 3.


4
Petitioner Montgomery KONE had a contract to modernize  the terminal's elevators.  To accommodate the piston that  powered the hydraulic mechanism of one of the elevators, a  seventy-two foot shaft was drilled into the pit's base.  To protect the piston from corrosion, the shaft had to be lined  with polyvinyl chloride ("PVC") plastic pipe, which came in  several sections.  Using PVC primer and liquid cement, both  of which contain flammable solvents that produce vapors 2.5  times heavier than air, Montgomery KONE employees working in the pit glued the sections together and then lowered  the assembled pipe into the shaft. Not long thereafter, when a  worker in the pit smelled fumes, a supervisor directed the  workers to insert a compressed air hose into the shaft to  expel the fumes.


5
Approximately a week to ten days after the PVC liner was  installed, while a Montgomery KONE worker assembling the  hydraulic mechanism was using a welding torch, an explosion  blew the PVC pipe out of the shaft.  The force of the  explosion threw the worker against the pit's wall,causing  multiple leg injuries.  Another worker, also thrown against  the wall, temporarily lost hearing in his left ear.  The two  workers escaped by climbing the extension ladder, the only  remaining way out--the explosion had cut the wooden ladder  at the back of the shaft in two, access to the iron ladder was  blocked, and the fiberglass ladder was not in the pit.


6
Following an inspection by OSHA Compliance Officers the  next day, the Secretary of Labor cited Montgomery KONE  for violating the confined space training regulations and  proposed a $3500 fine.  Montgomery KONE contested the  citation, triggering an evidentiary hearing before an Administrative Law Judge.  The ALJ vacated the citation, finding  that even though the pit satisfied one of section  1926.21(b)(6)(ii)'s requirements--it was subject to the accumulation of flammable contaminants--it did not qualify as a  confined space because it failed the other requirement:  due  to the presence of ladders, the means of egress was not  "limited."  See Sec'y of Labor v. Parsons Brinckerhoff  Constr. Services, Inc., ALJ Decision and Order at 6-7. Reversing the ALJ, the Occupational Safety and Health Review  Commission found that "conditions encountered in the elevator pit constituted a limited means of egress" both because  escape required climbing a ladder and because "[w]hen the  explosion occurred and the lights went out, the two employees  had to feel their way around in the dark until they found each  other, then found the ladder and helped each other get out of  the pit."  1999 OSHRC No. 37 at 9.  Finding that Montgomery KONE failed to provide confined space training, the  Commission imposed the $3500 fine.  See id. at 11.  Montgomery KONE appeals, arguing (1) that because of the  presence of ladders, egress from the pit was not limited, and  (2) that evidence demonstrates that the pit was not subject to  the accumulation of flammable contaminants.

II

7
As usual in cases of this kind, the outcome turns largely on  the standard of review.  Unlike in most administrative cases,  however, here we review the actions of two different entities,  each of which has a different function in the statute's enforcement scheme.  See Occupational Safety and Health Act of  1970, 29 U.S.C. §§ 651-78.  The Secretary promulgates and  enforces regulations;  the Commission has fact-finding and  adjudicatory powers.  See S.G. Loewendick & Sons, Inc. v.  Reich, 70 F.3d 1291, 1294 (D.C. Cir. 1995).  As a result, we  defer to the Secretary's interpretation of OSHA regulations  and to the Commission's fact-finding.  See id. at 1294.


8
In this case, the bifurcated standard of review has no  practical consequence.  Not only does Montgomery KONE  make nothing of it, but in her brief, the Secretary expressly  adopts the Commission's interpretation of section  1926.21(b)(6)(ii) as well as its factual conclusions.  Notwithstanding the involvement of two agencies, moreover, our  review is guided by traditional principles of administrative  law.  Of particular importance to this case, an agency's  interpretation of its own regulations "merits even greater  deference than its interpretation of the statute that it administers."  Buffalo Crushed Stone, Inc. v. Surface Transp. Bd.,  194 F.3d 125, 128 (D.C. Cir. 1999).  We will defer to the  Secretary's interpretation so long as it "sensibly conforms to  the purpose and wording of the regulations."  Id. at 128.  We  will accept the Commission's findings of fact if they are supported by "substantial evidence" and the Commission's  other findings and conclusions "if they are not arbitrary,  capricious, an abuse of discretion, or contrary to law."  Loewendick, 70 F.3d at 1294.


9
With this highly deferential standard in mind, we turn to  Montgomery KONE's arguments that the Commission's interpretation of the two elements of the confined space regulation--"limited ... egress" and "subject to the accumulation of  ... flammable contaminants"--is unreasonable, and that its  findings with respect to each are unsupported by substantial  evidence.

Limited Egress

10
To elucidate the meaning of "limited," the Commission  looked to Webster's New Collegiate Dictionary, which defines  the word to mean "restricted."  See 1999 OSHRC No. 37 at 8. The Commission then found that both physical and testimonial evidence demonstrated that egress from the pit was restricted.  Not only did photographic and video evidence show  that the only way out of the pit was through the use of  ladders, but both workers testified that in order to escape  from the pit after the explosion, they had to maneuver around  obstacles and then find and climb a ladder.  One of the  workers testified that confused and disoriented he felt his  way in the dark until he found his co-worker, who in turn  testified that he could neither hear nor see.  Both testified  that they helped each other escape from the pit.  Based on  such testimony, the Commission concluded that "[t]he employees may have been able to climb out of the elevator pit  without further problems, but the fact that they had to assist  one another supports our conclusion that their means of  egress was limited."  Id. at 9.  The Secretary agrees, explaining in her brief that "any means of egress is 'limited' for the  purposes of this standard unless it allows unimpeded egress  even under emergency conditions."


11
On appeal, Montgomery KONE points out--as it did before  the Commission--that a different OSHA regulation, one that  regulates the safety of trench excavations, expressly provides  that ladders are a "safe means of egress."  29 C.F.R.  § 1926.651(c)(2).  The Commission rejected this argument: "The fact that ladders are a 'safe' means of egress from a  trench for purposes of compliance with the excavation standard does not mean that they are not a 'limited' means of  egress for purposes of defining a confined space."  See 1999  OSHRC No. 37 at 8.  Indeed, in a previous decision involving  the excavation regulations, the Commission found that egress  that may not be "entirely free of difficulty" may still be  "safe."  Sec'y of Labor v. C.J. Hughes Constr., Inc., 17 O.S.H.  Cas. (BNA) 1753, 1754-56 (1996).  In view of this, and  because the excavation and confined space regulations deal  with different situations, the Commission's position in this  case seems eminently reasonable.


12
Equally without merit is Montgomery KONE's argument  that "egress" was not limited because the workers in fact had  no difficulty escaping from the pit.  To be sure, one worker  did so testify.  But the question we face is not whether  Montgomery KONE can unearth evidence to support its view  of what happened, but whether substantial evidence in the  record supports the Commission's version of events.  See  Harter Tomato Prods. Co. v. NLRB, 133 F.3d 934, 938 (D.C.  Cir. 1998).  Here, the question is not even close.  Not only do  photographic and video evidence demonstrate that ladders  provided the only means of egress from the pit, but workers  testified that after the explosion, they had trouble getting out. One worker testified:


13
I fell down into that area and I just sat there stunned and I heard Lou who was on the ladder on his way out. There was maybe two more rungs that he had to climb to get out so he had maybe a foot to a foot and a half.  He's still on the ladder and he says I....  I can't see.  I can't hear....  So we held each other, went up the other two rungs, got to the front of the pit and we let go of each other.

According to the other worker:

14
I was just pushed against the wall from the blast.... The lights went out.  I lost the hearing in my left ear....  I couldn't hear....  As I said the lights did go  out and I started calling for Dan and I couldn't see Dan because of the darkness.  Seconds later I felt Dan's hand on my shoulder saying let's get outand we both got up the ladder and climbed out of the pit. Given this evidence and our deferential standard of review,  we cannot imagine a basis for setting aside the Commission's  determination that in precisely the kind of circumstances  contemplated by these regulations--an explosion resulting  from the use of flammable materials--an almost five-foot  deep pit from which workers escaped only with the aid of a  single ladder satisfied the "limited egress" prong of the  confined space regulation.


15
Subject to the Accumulation of Toxic or Flammable Contaminants


16
The Commission concluded that "[t]he record clearly shows  that the elevator pit became subject to the accumulation of  heavier-than-air flammable vapors once Montgomery KONE  introduced the PVC primer and cement into the pit." 1999  OSHRC No. 37 at 6.  In reaching this conclusion, the Commission rejected Montgomery KONE's argument that the  confined space regulations did not apply because the company, having attempted to purge the vapors from the shaft,  could not have known they might remain over a week later. According to the Commission, "[w]here, as here ... an employer is responsible for introducing chemicals into the workplace, it also has a duty to learn about the characteristics of  those chemicals and to determine any dangerous conditions to  which the employees may be exposed as a result."  Id. at 6. The Commission explained:


17
The material safety data sheets for both the PVC primer and the PVC cement indicate that the vapor density is 2.49 times that of air.  That information should have informed Montgomery KONE's employees that they were dealing with vapors that would not all be blown out  of the seventy-foot-deep PVC liner with the compressed air they were using.


18
Id. at 7.  And in response to Montgomery KONE's evidence  that air samples taken from the pit both before and after the  explosion revealed no abnormalities, the Commission explained that whether the pit's atmosphere was actually contaminated at the time of the explosion had nothing to do with  whether the pit qualified as a confined space.  Rather, "the  presence of the flammable vapors in the PVC cylinder demonstrates that the elevator pit was subject to the accumulation  of flammable contaminants."  1999 OSHRC No. 37 at 8.


19
Montgomery KONE now reiterates its argument that tests  conducted before and after the explosion detected no vapors  in the pit.  It also points out that for three days prior to the  explosion, workers operated welding equipment in the pit  without incident.  Finally, the company claims that the explosion occurred in the shaft, not the pit, and that because the  shaft and the pit were separate spaces, the pit was not  subject to the accumulation of flammable contaminants.


20
All these arguments rest on a misunderstanding of the  Commission's reason for finding that the elevator pit was  subject to the accumulation of flammable contaminants.  To  the Commission, it made no difference that vapors had not  been detected either before or after the explosion, that no  explosion occurred during previous welding activity, or that  the explosion may have occurred in the shaft, not the pit. Instead, the Commission found--and the Secretary agrees-that the presence in the shaft of flammable contaminants 2.5  times heavier than air effectively made the pit "subject to the  accumulation of ... flammable contaminants."  The Secretary cites the ALJ's finding approvingly:


21
"The statement that there is no relationship between the explosion and the elevator pit blinks at reality.... [T]he effects of the explosion were felt in the pit....  To hold that this pit does not fall within the definition set out in § 1926.21(b)(6)(ii) because a flammable gas accumulated and exploded in a cylinder placed in a hole in the  pit's floor, rather than in the pit itself, elevates technical distinctions to an unwarranted level of importance."


22
ALJ Decision and Order at 5-6.  Given the deference we owe  an agency regarding the interpretation of its own regulations,  and given the evidence in the record of heavier-than-air  vapors in the shaft, we see no basis for overturning the  Commission's conclusion that the pit met the second prong of  the confined space standard.

III

23
In light of the fact that the pit qualified as a confined space  within the meaning of section 1926.21(b)(6)(ii), Montgomery  KONE had an obligation to provide confined space training  pursuant to 29 C.F.R. § 1926.21(b)(6)(i):  "[a]ll employees  required to enter into confined or enclosed spaces shall be  instructed as to the nature of the hazards involved, the  necessary precautions to be taken, and in the use of protective and emergency equipment required."  Reviewing the  record, the Commission concluded that Montgomery KONE  failed to provide confined space training to workers required  to enter the elevator pit.  See 1999 OSHRC No. 37 at 6. Indeed, according to the Commission, the workers' immediate  supervisor expressly testified that "the company did not  provide confined space training because it did not work in any  confined spaces."  Id. at 6 n.3.


24
Montgomery KONE argues that it had no reason to believe  that the precautions it took to guard against the accumulation  of flammable vapors were insufficient to prevent the explosion.  As the Secretary points out, however, this has nothing  to do with Montgomery KONE's obligations under the confined space training regulation.  Given the supervisor's concession that the company provided no confined space training,  we affirm the Commission's order and citation.


25
So ordered.

