Tcp Specialists, LLC v. Secretary of Labor

United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued March 30, 2026 Decided June 12, 2026
No. 25-1173
TCP S PECIALISTS, LLC,
P ETITIONER
v.
S ECRETARY OF LABOR ,
R ESPONDENT
On Petition for Review of an Order of the
Occupational Safety & Health Review Commission
Darren S. Harrington argued the cause for petitioner.
With him on the briefs was Brian L. Hurt.
Joseph J. Quick, Attorney, U.S. Department of Labor,
argued the cause for respondent. With him on the brief were
Jonathan Berry, Solicitor of Labor, Edmund C. Baird,
Associate Solicitor for Occupational Safety and Health,
Heather R. Phillips, Counsel for Appellate Litigation, and
Anne E. Bonfiglio, Attorney. Amy S. Tryon and Louise Betts,
Attorneys, entered appearances.

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Before: H ENDERSON and C HILDS , Circuit Judges, and
R ANDOLPH , Senior Circuit Judge.
Opinion for the Court filed by Circuit Judge HENDERSON.
KAREN LEC RAFT HENDERSON, Circuit Judge: After a
pressurized pipe ruptured and struck employees at an oil well,
the Secretary of the Department of Labor (Labor) issued a
citation to petitioner, TCP Specialists, LLC (TCP). TCP did
not provide the piping and did not direct the depressurizing
operation that led to the accident. But TCP’s employees were
standing unnecessarily close to the depressurizing well, the
Secretary alleged, creating a risk that they would be struck by
equipment or caught in an explosion. He also contended that
TCP feasibly could have abated that hazard by establishing a
buffer zone around the well. Following a three-day evidentiary
hearing, an administrative law judge (ALJ) agreed and upheld
the citation. TCP petitioned for review, maintaining, among
other things, that the ALJ violated Occupational Safety and
Health Review Commission (Commission or OSHRC)
precedent in defining the hazard; that substantial evidence does
not support the ALJ’s factual findings; and that one provision
of the Occupational Safety and Health Act (OSH Act) is
unconstitutional as applied to it. Finding each claim meritless,
we deny the petition.
I. BACKGROUND
A
In the 1970 OSH Act, Pub. L. No. 91-596, 84 Stat. 1590,
the Congress sought to promote “safe and healthful working
conditions” for “every working man and woman in the Nation.”
29 U.S.C. § 651(b). To attain that goal, the Act divided
implementing authority between the Labor Secretary and the

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Commission. The Secretary enforces health and safety
standards by promulgating rules and issuing citations. Martin
v. OSHRC, 499 U.S. 144, 147 (1991); see 29 U.S.C. §§ 655,
658. The Commission “act[s] as a neutral arbiter and
determine[s] whether the Secretary’s citations should be
enforced over employee or union objections.” Cuyahoga
Valley Ry. Co. v. United Transp. Union, 474 U.S. 3, 7 (1985)
(per curiam); accord 29 U.S.C. §§ 651(b)(3), 661. The
employer may contest the Secretary’s allegations before a
Commission ALJ. Atlas Roofing Co. v. OSHRC, 430 U.S. 442,
446 (1977); 29 U.S.C. §§ 659, 661(j). Absent the
Commission’s discretionary review, the ALJ decision becomes
a final order of the Commission. Atlas Roofing, 430 U.S. at
446; 29 U.S.C. § 661(j).
Section 654 equips the Secretary with two bases of
enforcement. First, the Secretary may allege a violation of the
specific health and safety standards promulgated under the Act.
29 U.S.C. § 654(a)(2); Nat’l Realty & Constr. Co. v. OSHRC,
489 F.2d 1257, 1261 (D.C. Cir. 1973). Courts sometimes refer
to this basis as the “[S]pecific [D]uty [C]lause.” E.g., Carlyle
Compressor Co. v. OSHRC, 683 F.2d 673, 676 (2d Cir. 1982).
Second, the Secretary may allege a violation of the “General
Duty Clause,” which is the one of the two clauses relevant here.
29 U.S.C. § 654(a)(1); Nat’l Realty, 489 F.2d at 1261. The
General Duty Clause functions as a gap-filler, providing “an
enforcement mechanism when no specific OSHA standard
applies to a particular hazard.” Interpretation of the General
Duty Clause, 90 Fed. Reg. 28370, 28371 (proposed July 1,
2025) (to be codified at 29 C.F.R. pt. 1975). Under it, each
employer must “furnish to each of his employees employment
and a place of employment which are free from recognized
hazards that are causing or are likely to cause death or serious
physical harm to his employees.” 29 U.S.C. § 654(a)(1). We
have interpreted that directive to encapsulate four elements:

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(1) an activity or condition in the employer’s
workplace presented a hazard to an employee,
(2) either the employer or the industry
recognized the condition or activity as a hazard,
(3) the hazard was likely to or actually caused
death or serious physical harm, and (4) a
feasible means to eliminate or materially reduce
the hazard existed.
BHC Nw. Psychiatric Hosp., LLC v. Sec’y of Lab., 951 F.3d
558, 563 (D.C. Cir. 2020) (citation modified).
B
The accident underlying this petition unfolded at the
Blackstone B1 well, a gas well in San Augustine County,
Texas. C6 Operating (C6), an oil and gas producer, operated
the wellsite. In October 2022, C6 hired contractors to perform
a “workover,” J.A. 18, aimed at “maintaining or restoring the
productivity of [the] well,” 30 C.F.R. § 250.601. Several
contractors are key to the story. One contractor, Jaguar Energy
Services, operated a “frac stack,” which is an assemblage of
valves, handwheels and other equipment used to control a
well’s flow rate and pressure. J.A. 18. Jaguar also provided
the piping used to transport fluids and pressure to and from the
well. Another contractor, Reliance Well Services, operated a
“pump tank,” an apparatus used to draw pressure from the well,
through the frac stack and piping and, finally, to itself. J.A. 18.
Generally speaking, then, Jaguar and Reliance controlled the
well’s flow rate and pressure.
Petitioner TCP provided wireline services. In the oil and
gas industry, these “involve using a specialized cable to lower

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tools and equipment into a well[].” Panuswee Dwivedi,
Wireline Services, ADI Analytics (May 29, 2025), https://adi-
analytics.com/2025/05/29/wireline-services-supporting-the-oil
-gas-industry-through-evolving-depths/ [https://perma.cc/CN6W-
L4JQ]. Often, contractors use wireline services to complete
routine maintenance in or gather geophysical data from a well.
See Domingue v. Ocean Drilling & Exploration Co., 923 F.2d
393, 394 n.3 (5th Cir. 1991).
On December 5, 2022, a TCP crew consisting of three
employees arrived at the well. They agreed to perform two
wireline operations. The first of these, lasting approximately
two hours, they executed without issue. Before the second
operation, however, Jason Walker—a TCP supervisor—
noticed that the well’s pressure had increased. He notified
three non-TCP employees of this fact and the group agreed to
depressurize the well during the second wireline operation. As
TCP undertook that operation, however, Walker realized that
the well’s pressure had nearly doubled, meaning that no one
had depressurized it. Walker sent another TCP employee,
Tristan McLelland, to apprise the wellsite general supervisor.
After McLelland relayed the message, a small group of
employees congregated at the wellhead. At this point, several
factors combined to produce catastrophe. The wellsite general
supervisor instructed a Jaguar supervisor to depressurize the
well by opening a valve on the frac stack. Contrary to protocol,
however, the Jaguar supervisor opened one valve without
ensuring that another was fully shut. Instead of slowly
depressurizing the well as the supervisor had intended, this
sequence released a flood of pressure from the well into the
pipe. Jaguar had borrowed that pipe from Reliance earlier in
the day but, unbeknownst to either, the pipe had corroded. The
sudden pressure caused the corroded pipe to rupture and flail
violently, striking several employees and throwing one nearly

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sixty feet. As a result of the accident, one TCP employee was
hospitalized; two other employees—the wellsite general
supervisor and a Jaguar employee—died.
C
The Secretary cited TCP for a serious violation of the OSH
Act’s General Duty Clause, 29 U.S.C. § 654(a)(1). He alleged
that TCP’s employees had been standing unnecessarily close
“to the frac stack and pressured piping” during the
depressurization, which had exposed them to “fire, explosion,
and struck-by hazards.” J.A. 6. He also noted two abatement
measures that could have prevented the accident. The first of
these, sensibly enough, was to establish a buffer zone around
the wellhead. The second was to restrain the pressurized piping
to ensure that it did not whip. TCP contested the citation and
the parties proceeded to an evidentiary hearing.
At the hearing, the ALJ considered testimony from the
three TCP employees who had been at the wellsite. He also
heard testimony from two experts—Paul Luker, whom the
Secretary called, and Jarold Elgin, whom TCP called. Luker’s
testimony constituted much of the Secretary’s evidence on the
issues relevant to TCP’s petition and, accordingly, we focus on
his testimony. At the time, Luker was an independent safety
consultant in the oil and gas industry. Within that industry, he
had around thirty-five years of safety-related experience. He
spent almost all of his time visiting job sites to review their
safety protocols and devoted about thirty per cent of that time
to workovers. The Secretary tendered Luker “as an expert in
the oil and gas industry[,] specifically on workover
operations . . . and the safety policies and procedures of those
operations,” J.A. 644, and the ALJ admitted Luker as an expert
in those fields.

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To reach his opinion, Luker considered technical
literature, industry publications, witness depositions, the
Secretary’s description of the accident and reports filed by the
on-site contractors. He drew three relevant conclusions. First,
he concluded that a buffer zone around the wellhead would
have materially reduced the risk of harm to TCP’s employees.
Citing evidence that no employee farther than 100 feet away
had been injured, Luker testified that a buffer zone of that size
would have sufficed. Second, he concluded that a “reasonably
prudent employer” in TCP’s shoes would have established such
a buffer zone. J.A. 737–38. He explained that employers in
the industry “routinely” employ 100-foot buffer zones during
comparable operations and that industry standards, training and
risk assessments recommend such buffer zones. J.A. 786.
Third, Luker testified that TCP feasibly could have
implemented a buffer zone because it was not necessary for its
employees to stand near the wellhead during the
depressurization. Tristan McLelland, who notified the wellsite
general supervisor of the elevated pressure, could have held
that conversation almost anywhere on the jobsite. And Brian
Walker, asked to monitor pressure, did not need to do so until
later in the operation and he could have carried out his task
away from the wellhead. In sum, Luker testified, a buffer zone
was an effective means of abatement and one that TCP feasibly
could have implemented.
The ALJ determined that the Secretary’s evidence satisfied
the General Duty Clause’s four elements. TCP Specialists,
LLC, No. 23-1002, 2025 WL 1735784, at *5–18 (OSHRC May
12, 2025) (ALJ). First, he concluded that a “hazard” existed.
Id. at *8. That hazard, he explained, was the risk posed by the
employees’ “close proximity to the frac stack and pressurized
piping during depressurization of the frac stack.” Id. Second,
the ALJ concluded that the hazard was “recognized” and a
supervisor’s hazard recognition can be imputed to the

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employer. Id. Supervisor Jason Walker testified that he knew
depressurizing a well created serious risks, including the pipe
“exploding, rupturing, and whipping around.” Id. Third, the
ALJ found that the hazard caused or was likely to cause “death
or serious physical harm.” Id. at *9 (citation modified). For
evidence of that, the ALJ reasoned, one need look no further
than the underlying accident itself, as well as the deaths and
injuries it caused. Id. Fourth, the ALJ found that the hazard
was “preventable.” Id. at *9–18. Recall that the Secretary had
proposed two measures by which TCP could have abated the
hazard—(1) establishing a buffer zone or (2) restraining the
pressurized piping. The ALJ rejected the latter, concluding that
TCP had no authority to impose line restraints at the well. Id.
at *10–11. But he accepted the former, determining that TCP
could have feasibly established a buffer zone around the
depressurizing well and that such a buffer zone would have
materially reduced the risk of harm to its employees. Id. at
*11–18. Finding the General Duty Clause’s elements met, the
ALJ upheld the citation and assessed a corresponding penalty
of $6,250. Id. at *23.
OSHRC denied TCP’s request for discretionary review.
The ALJ’s decision therefore became a final order of the
Commission. See 29 U.S.C. § 661(j). From that order, TCP
filed this timely petition for review.
II. ANALYSIS
We have jurisdiction of TCP’s petition under 29 U.S.C.
§ 660(a). We review the ALJ’s factual findings for substantial
evidence, id., and will overturn the ALJ’s application of the law
to the facts only if it is “arbitrary, capricious, an abuse of
discretion, or contrary to law,” 5 U.S.C. § 706(2)(A). Otis
Elevator Co. v. Sec’y of Lab., 762 F.3d 116, 120–21 (D.C. Cir.
2014) (citation modified).

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A
TCP asserts that the ALJ deviated from Commission
precedent in defining the underlying hazard. That precedent
imposes two relevant requirements. The Secretary must define
the hazard “in terms of the physical agents that could injure
employees,” rather than in terms of the absence of a proposed
abatement. Chevron Oil Co., 1983–1984 CCH OSHD ¶ 26507,
1983 WL 23864, at *1–2 nn.5–6 (No. 10799, 1983). And the
Secretary must identify a hazard composed of “conditions or
practices” over which the employer can exercise control.
Arcadian Corp., 2005 CCH OSHD ¶ 32756, 2004 WL
2218388, at *7 (No. 93-0628, 2004). We consider each in turn.
TCP first contends that the ALJ impermissibly defined the
hazard as the absence of an abatement. It emphasizes that the
Secretary alleged that TCP had exposed its employees to a
hazard because they were standing in “close proximity” to the
wellhead during depressurization. Pet’r’s Br. 17 (quoting J.A.
6). But, TCP asserts, that is just another way of saying that
TCP had failed to establish a buffer zone, which doubled as the
Secretary’s proposed abatement measure in this case.
TCP misreads the record. No one defined the hazard as
the absence of a buffer zone. Instead, the Secretary and ALJ
both identified the hazard by reference to the physical agents
composing it—the frac stack and pressured piping. This much
is plain from both the citation itself as well as the ALJ’s order.
In the citation, the Secretary alleged that TCP’s employees
“were exposed to fire, explosion, and struck-by hazards”
during the depressurization. J.A. 6. He then specifically
identified the “frac stack and pressured piping” as the physical
agents underlying that risk. J.A. 6. The ALJ confirmed this
understanding, explaining that the “hazardous condition” was

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the risk created by the employees’ proximity to the
depressurizing frac stack—proximity that exposed the
employees “to fire, explosion, and struck-by hazards.” TCP
Specialists, 2025 WL 1735784, at *8. In other words, the
Secretary and ALJ accurately described the hazard by reference
to objects composing it—the frac stack and pressured piping.
Both are “physical agents” within the meaning of Commission
precedent. Chevron Oil Co., 1983 WL 23864, at *2 n.6; see id.
at *2 (corroded piping); cf. Arcadian Corp., 2004 WL
2218388, at *8 (pressurized reactor). And neither can be
described as the absence of a particular abatement measure.
Granted, the citation and order also described the
employees’ “close proximity” to the wellhead as part of the
hazard. J.A. 6. But that is not inconsistent with Commission
precedent. Like most potentially hazardous operations, the
depressurization posed a risk of harm only to those standing
nearby. See, e.g., Coastal Drilling E., LLC, 2019 CCH OSHD
¶ 33701, 2018 WL 7080227, at *3, *5 (No. 17-1179, 2018)
(ALJ) (crushing hazard); cf. Mo. Basin Well Serv., 2018 CCH
OSHD ¶ 33648, 2018 WL 1309482, at *2–3 (No. 13-1817,
2018) (“unsafe distance” between two objects). Nothing in
Commission precedent forbade the ALJ from recognizing that
fact.
TCP next argues that, in defining the hazard, the ALJ
failed to identify “conditions or practices” over which TCP
exercised control. Pet’r’s Br. 29 (citation modified). In TCP’s
view, it lacked any control over the depressurization, which
Jaguar performed, or the corroded pipe, which Reliance
provided. And, it maintains, those were the only conditions
making up the hazard.
As noted above, however, the employees’ proximity to the
wellhead was a necessary component of the hazard. TCP

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exercised control over that proximity: the ALJ made a factual
finding, which TCP has not challenged, that TCP controlled its
employees’ conduct and location during the depressurization.
TCP Specialists, 2025 WL 1735784, at *6, *8. Because the
ALJ identified a condition or practice over which TCP did, in
fact, exercise control, it did not run afoul of Commission
precedent.
B
TCP next challenges the evidence supporting the ALJ’s
finding that it could have prevented the hazard. Specifically,
TCP assails the ALJ’s conclusions that a buffer zone would
have materially reduced the risk of harm to its employees and
would have been feasible to employ. It also challenges the
ALJ’s finding that its existing safety procedures were
inadequate.
The substantial-evidence standard is not exacting. Biestek
v. Berryhill, 587 U.S. 97, 103 (2019). It requires only “such
relevant evidence as a reasonable mind might accept as
adequate to support a conclusion”—a threshold the Supreme
Court has described as “more than a mere scintilla.” Consol.
Edison Co. v. NLRB, 305 U.S. 197, 229 (1938). In applying
the standard, we must adopt “a very high degree of deference,”
Island Architectural Woodwork, Inc. v. NLRB, 892 F.3d 362,
370 (D.C. Cir. 2018) (citation modified), affirming the
agency’s findings “unless no reasonable factfinder could find
as [it] did.” Hood River Distillers, Inc. v. NLRB, 130 F.4th 204,
216 (D.C. Cir. 2025) (citation modified). Nevertheless,
substantial-evidence review demands more than “inordinate
faith in the conclusory assertions of an expert.” Sea Robin
Pipeline Co. v. FERC, 795 F.2d 182, 188 (D.C. Cir. 1986).

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This standard is easily met here. First, substantial
evidence supported the ALJ’s finding that a buffer zone would
have materially reduced the risk of harm to TCP’s employees.
Luker testified that this was so. As he explained, the “further
back” an employee is from the hazard, “the less likely” he is
“to suffer impact” and, even if he does, the “severity of the
impact will be greatly reduced.” J.A. 810. In Luker’s
experience, risk assessments for operations like the one here
call for a 100-foot buffer zone around the wellhead for
nonessential personnel. And the industry arrived at the 100-
foot figure in particular, he went on, because it is sufficient both
to “provide a safe zone” and to obviate the need for employees
to execute complex, back-of-the-napkin calculations while out
in the field. J.A. 785. Indeed, TCP’s own expert agreed that a
100-foot buffer zone, if used, would have reduced the risk of
harm to TCP’s employees. The underlying facts provided
direct evidence bolstering that conclusion: no employee
outside Luker’s proposed buffer zone was injured in the
accident. This combination of uncontested expert testimony
and direct evidence constitutes substantial evidence. See Am.
Wrecking Corp. v. Sec’y of Lab., 351 F.3d 1254, 1262 (D.C.
Cir. 2003).1
TCP emphasizes that pipe fragments were found more
than 100 feet away. But the ALJ considered that potentially
contradictory evidence and explained why he did not find it
persuasive. TCP Specialists, 2025 WL 1735784, at *13–15.
The ALJ is entitled to choose between conflicting
interpretations of the evidence and where, as here, that choice
1 We do not conclude that a 100-foot buffer zone is
required during all depressurizing operations but only that
substantial evidence supports the ALJ’s determination that it
was necessary here.

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is supported by substantial evidence, we must respect it.
Perdue Farms, Inc. v. NLRB, 144 F.3d 830, 838 (D.C. Cir.
1998).
TCP also asserts that no substantial evidence supported the
ALJ’s finding that a buffer zone was compatible with its
employees’ essential tasks such that employing a buffer zone
would have been feasible. We disagree. The Secretary asked
Luker expressly whether either of the TCP employees inside
his proposed buffer zone was “performing essential work”
during the depressurization. J.A. 747. Luker testified that both
were not. McLelland could have spoken to the wellsite general
supervisor anywhere at the jobsite. And Brian Walker did not
need to be monitoring the pressure during that stage of the
operation and could have stood away from the wellhead while
doing so. Luker’s conclusion finds support in industry
practice, which can be “highly probative” of “feasibility.” L.R.
Willson & Sons, Inc. v. OSHRC, 698 F.2d 507, 514 (D.C. Cir.
1983). The oil and gas industry often employs or recommends
buffer zones in situations where, as here, a pipe is being
pressurized. In conjunction with Luker’s expert testimony, that
industry practice serves as substantial evidence that a buffer
zone was feasible.
In addition, TCP maintains that the Secretary failed to
show that its existing safety measures were inadequate. As it
observes, we have stated that if “an employer has existing
safety procedures, the burden is on the Secretary to show that
those procedures are inadequate” to abate the hazard.
SeaWorld of Fla., LLC v. Perez, 748 F.3d 1202, 1215 (D.C.
Cir. 2014). But the key predicate is “existing safety
procedures.” TCP apparently had none. Its employees
repeatedly acknowledged that TCP had no policies or
procedures in place that were responsive to the hazard. The
employees did hold a small safety meeting at the start of the

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workday. But they did not even discuss pressurized equipment
at the meeting. It is unclear, then, what relevant safety
procedures TCP believes that it had in place. And it cites
nothing in the record to support its argument. Thus,
uncontradicted employee testimony supports the ALJ’s finding
that TCP had established no “rules or an alternative abatement
method” for the hazard at issue here, TCP Specialists, 2025 WL
1735784, at *13, and for that reason we reject TCP’s claim.
C
Finally, TCP contends that the General Duty Clause is
unconstitutionally vague as applied to it. It does not deny that
we have repeatedly rejected vagueness challenges to the
General Duty Clause because there is little fair-notice concern
if the hazard is “preventable” and “a reasonably prudent
employer in the industry would have known that the proposed
method of abatement was required.” BHC Nw. Psychiatric
Hosp., 951 F.3d at 566 (citation modified). Rather than
confronting that caselaw head-on, TCP advances a slightly
different argument. Specifically, TCP contends that the
definition the Secretary and ALJ gave the hazard was so
“broadly worded” that it failed to provide TCP fair notice of its
obligations. Pet’r’s Br. 24. In the citation, TCP emphasizes,
the Secretary stated that TCP’s employees were “standing in
close proximity to pressurized equipment.” Pet’r’s Br. 24
(quoting J.A. 6). And in his order, the ALJ at times seemed to
define the hazard in the same way. TCP Specialists, 2025 WL
1735784, at *7. But if simply standing near pressurized
equipment—which is ubiquitous in the oil and gas industry—
violates the General Duty Clause, then, TCP says, the clause
itself is unconstitutional.
Again, TCP misreads the record. The Secretary’s
allegations have consistently been keyed to a discrete

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operation—depressurization—rather than the dangers of
pressurized equipment in general. As the Secretary explains:
“The hazard is not, as TCP repeatedly phrases it, ‘working in
proximity to pressurized equipment.’ The depressurization
activity is key to the existence of the hazard.” Secretary’s Br.
25 n.10 (citations omitted). That understanding has been
common ground throughout the proceedings, as reflected in the
citation, the Secretary’s opening statement, witness testimony
and the ALJ’s order.2 Indeed, TCP itself seems, once, to have
shared that understanding. In its petition for discretionary
Commission review, TCP described the alleged hazard as its
employees’ “expos[ure] to fire, explosion and struck-by
hazards while depressurizing a frac stack.” J.A. 89. It is only
now that TCP—and TCP alone—seems to misunderstand the
contours of the hazard for which it was cited. Its
misunderstanding cannot be traced to any defect of notice, and,
accordingly, we reject TCP’s claim.
* * *
TCP also argues that it lacked knowledge of the violative
conditions and that the Secretary failed to establish hazard
recognition. We have considered and rejected these arguments.
To the extent TCP raises other arguments, they are either
plainly groundless or undeveloped and thus forfeited.
2 Even if the ALJ used shorthand once or twice in
suggesting that pressurized equipment itself created the risk, he
left little doubt about the nature of the hazard when he said:
“The hazardous condition here was TCP’s employees standing
in close proximity to the frac stack and pressured piping during
depressurization of the frac stack, which exposed them to fire,
explosion, and struck-by hazards.” TCP Specialists, 2025 WL
1735784, at *8.

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For the foregoing reasons, TCP’s petition for review is
denied.
So ordered.

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