In the
 United States Court of Appeals
               For the Seventh Circuit
                          ____________

No. 04-2506
WILLIAM T. KILLMAN,
                                                         Petitioner,
                                 v.

DIRECTOR, OFFICE OF WORKERS’ COMPENSATION
PROGRAMS, UNITED STATES DEPARTMENT OF LABOR,
and SAHARA COAL TRUST,
                                                     Respondents.
                          ____________
    Petition for Review of an Order of the Benefits Review Board,
                 United States Department of Labor.
                          No. 99-BLA-0760.
                          ____________
    ARGUED JANUARY 26, 2005—DECIDED JULY 19, 2005
                    ____________




  Before POSNER, MANION, and WOOD, Circuit Judges.
  WOOD, Circuit Judge. William Killman worked for
twenty-three years for the Sahara Coal Company (Sahara),
eventually rising to the position of foreman. He retired from
mining at the end of September, 1984; about six months
later, he began his quest for black lung disability benefits
under the Black Lung Benefits Act. After several hearings,
appeals to the Benefits Review Board (“the Board”), re-
mands, and rehearings, an ALJ ultimately denied benefits
and the Board affirmed. Killman petitions for review of this
2                                              No. 04-2506

decision. Because the ALJ never definitively resolved what
the exertional requirements of Killman’s job were, and he
never ensured that the physicians on whom he relied had
based their opinions on the correct exertional requirements,
we grant the petition for review and vacate and remand the
Board’s decision.


                             I
  For fourteen years of his tenure with Sahara, Killman
worked as a mine foreman. Along the way, he developed
unspecified respiratory problems and apparently suffered
a heart attack. On February 19, 1985, more than twenty
years ago, Killman filed a claim for black lung disability
benefits. The Department of Labor denied the claim, lead-
ing to a hearing before an ALJ in 1987.
  In a 1988 decision, the ALJ ruled in Killman’s favor, cre-
diting the testimony of physicians who had concluded that
Killman was disabled as a result of black lung disease. The
ALJ ordered Sahara (whose liabilities in this respect later
were transferred to the Sahara Coal Trust) to pay benefits
under the Black Lung Benefits Act retroactive to 1985. The
ALJ determined that medical test results alone did not
support a diagnosis of pneumoconiosis (black lung disease),
but correctly noted that notwithstanding negative x-rays, a
diagnosis may be confirmed by a physician “exercising
sound medical judgment.” The ALJ credited the testimony
of three doctors, each of whom diagnosed Killman with
black lung disease, and accordingly found that Killman had
“established the existence of pneumoconiosis.” The ALJ
further found that Killman’s disability was “total,” noting
that all of the testifying physicians agreed that Killman
was disabled in that he could not perform the tasks of his
last job as foreman with Sahara.
  Sahara and the Department of Labor appealed the ALJ’s
decision to the Benefits Review Board, which in 1993 partly
No. 04-2506                                               3

vacated the order and remanded the case for further
consideration on the question whether Killman was totally
disabled because of pneumoconiosis. The Board found fault
with the ALJ’s reliance on medical testimony that did not
consider Killman’s smoking habit or history of heart disease
as potential causes of disability. Based on these errors, as
well as other concerns over the ALJ’s use of medical testi-
mony, the Board sent the case back to the ALJ “to recon-
sider the evidence and first determine whether claimant
has established a totally disabling respiratory impairment”
resulting from pneumoconiosis.
  On remand, the ALJ reviewed the medical testimony and
concluded that some of the medical tests underlying the
earlier result were invalid. Relying on the changed factual
background, he denied Killman’s claim for benefits. The
ALJ acknowledged that the medical testimony on which he
had relied in his earlier order was “not well reasoned”
because there was no indication of how the doctors who
found Killman disabled could have reached their conclusion
without using the faulty tests. This time around, the ALJ
credited the testimony of two doctors who opined that
Killman suffered from at most a mild respiratory impair-
ment that would not prevent him from carrying out his
tasks as foreman. Killman appealed this decision, and in
1994 the Board affirmed. The Board found that the ALJ
“properly considered all relevant evidence of record” and
properly relied on the medical testimony indicating that
Killman’s ailment was not totally disabling.
  In 1997, Killman filed a new claim for benefits. A differ-
ent ALJ handled this filing and characterized it as duplica-
tive. This meant that, in order to be awarded benefits,
Killman would have to show that there had been a material
change in his condition. See Sahara Coal Co. v. OWCP, U.S.
Dept. of Labor, 

(7th Cir. 1991). Because the
earlier decision had established that Killman was suffering
from pneumoconiosis, this ALJ determined that Killman
4                                               No. 04-2506

would have to “establish a material change in condition
with respect to disability.” Practically speaking, Killman
had the burden of showing that he had become totally
disabled in the time since his original claim was denied in
order to qualify for black lung benefits.
  Under the relevant regulations, a claimant can show total
disability “if a physician exercising reasoned medical
judgment . . . concludes that the claimant’s respiratory or
pulmonary condition prevents or prevented the miner from
engaging in employment as described in paragraph (b)(1) of
this section.” 20 C.F.R. § 718.204(c)(4). The regulation
specifies that a miner is totally disabled if his respiratory
or pulmonary condition is in itself enough to prevent him
from “performing his or her usual coal mine work.” 20
C.F.R. § 718.204(c)(4). The ALJ’s decision therefore turned
on medical opinions on the question whether Killman’s
respiratory problems prevented him from working in the job
of mine foreman that he had held.
  The testimony of four doctors was particularly important
to the case. These doctors based their opinions on medical
tests and examinations done both before and after the previ-
ous hearings. While many doctors provided testimony and
reports over the history of this case, the ALJ relied prin-
cipally on the testimony of Drs. Tuteur, Dahhan, Renn, and
Cohen. Each of these doctors examined Killman at various
times during the adjudication of his claim for benefits.
Moreover, these doctors shared consultative reports with
each other and reviewed each others’ conclusions. In the
end, Drs. Tuteur, Dahhan, and Renn concluded that
Killman was not totally disabled; only Dr. Cohen deter-
mined that he was.
  Drs. Tuteur, Dahhan, and Renn each diagnosed Killman
with a mild “obstructive defect” attributable to smoking
rather than pneumoconiosis. Dr. Cohen, in contrast, found
that Killman was totally disabled, and attributed this prim-
No. 04-2506                                                 5

arily to coal dust exposure. Dr. Cohen thought that
Killman’s smoking habit was at best a contributory factor.
The ALJ was impressed by Drs. Tuteur, Dahhan, and Renn,
describing their opinions as “well reasoned, well docu-
mented, supported by the evidence, and entitled to sub-
stantial weight.” In contrast, the ALJ conceded that
“Dr. Cohen has some expertise in this area,” but he declined
to credit Dr. Cohen’s opinion in the face of the assessment
of the other three and the fact that none of the medical tests
produced results that clearly qualified Killman as disabled
under 20 C.F.R. § 718.204(b)(2)(i), (ii). The ALJ concluded,
“After weighing all of the new medical evidence and placing
greater weight on the three opinions by Drs. Tuteur,
Dahhan, and Renn, I find that the evidence does not
establish a material change in condition.” Accordingly, the
ALJ denied Killman’s claim for black lung benefits.
   Killman again appealed the denial to the Board, which
vacated the order after finding that the ALJ “did not ad-
dress the contention below that Drs. Renn, Dahhan, and
Tuteur did not understand the exertional requirements” of
the job that all three agreed he would be able to perform.
The Board found that Killman’s duties as foreman included
inspecting eight different mine faces, which required him to
walk 960 feet in 20 minutes “while bent over in low coal and
carrying approximately thirty pounds of equipment.” In
addition, the Board noted that Killman was responsible for
assisting with a variety of tasks around the mine site, such
as lifting oil barrels and changing tires. The Board was
troubled by the failure of Drs. Tuteur, Dahhan, and Renn to
demonstrate an awareness of these duties. According to the
Board, these physicians either did not discuss Killman’s
duties or were under the impression that those duties were
light. The Board also noted that the ALJ did not make a
finding about the range of Killman’s duties as a foreman.
The Board held that the ALJ “should not have assessed the
physicians’ reasoning based solely on the non-qualifying
6                                                No. 04-2506

nature of the claimant’s objective tests,” citing Poole v.
Freeman United Coal Mining Co., 

, 894 (7th
Cir. 1990). The Board remanded the case to the ALJ “to
consider the evidence regarding the exertional requirements
of claimant’s usual coal mine work as a foreman, to make a
finding as to the nature of that work, and then to reweigh
the new medical opinion evidence to determine whether
claimant’s respiratory impairment prevents him from
performing that work.”
  On remand, the ALJ focused on the various doctors’ un-
derstanding of Killman’s duties. Dr. Cohen described
Killman’s duties in the greatest detail, such as specifying
the distances Killman was required to walk and the loads
he was required to carry. The other doctors, including
Drs. Tuteur, Renn and Dahhan, “reviewed” Dr. Cohen’s
reports, which the ALJ understood to mean that they read
the job requirements “as written and understood by
Dr. Cohen.” Some of Dr. Cohen’s conclusions, however, were
erroneous. Dr. Cohen mistakenly wrote in an early report
that Killman “was required to walk 60 feet every 20 min-
utes to one of the eight face areas for inspection.” The other
physicians, having reviewed Dr. Cohen’s early report,
repeated this error in their own testimony.
  The ALJ comprehensively reviewed and recited the
various physicians’ understanding of Killman’s work re-
quirements, but then he expressed some confusion about
what he was expected to do with this information. He ac-
knowledged that the Board expected him “to consider the
evidence regarding the exertional requirements of the
Claimant’s usual coal mine work as a foreman, to make a
finding as to the nature of that work, and then to reweigh
the new medical opinion evidence” in order to determine
whether Killman was totally disabled, but he refused to do
so, stating:
    If the Board means that the Administrative Law Judge
    is to substitute his opinion for that of the physician,
    where the physician has an adequate understanding of
No. 04-2506                                                 7

    the Miner’s job duties, in determining whether the
    Miner’s job duties are mild, moderate, or strenuous, I
    decline to do so. For the Administrative Law Judge to
    take such action would substitute his opinion for that of
    the physician. Although the weighing of the evidence is
    for the Administrative Law Judge, the interpretation of
    medical data is for the medical experts. Accordingly, it
    is error for an Administrative Law Judge to interpret
    medical tests and thereby substitute an adjudicator’s
    conclusions for those of the physician.
Accordingly, the ALJ found that Killman had not estab-
lished a material change in his condition and was not enti-
tled to black lung benefits. The ALJ based this decision on
“the reports of the physicians, the qualifications of the phy-
sicians, the reasoning of the physicians and the objective
tests on which they relied.”
  Once again, Killman appealed, and a divided Board
affirmed the ALJ’s order as supported by substantial evi-
dence. The Board held that the ALJ’s decision met this
standard in that he “extensively discussed the job duties
and exertional requirements of claimant’s usual coal mine
employment,” and that four of the five physicians, including
two examining physicians, concurred that Killman was not
totally disabled. One administrative appeals judge dis-
sented on the ground that the ALJ “has failed to comply
with the Board’s remand instructions to determine the exer-
tional requirements of claimant’s usual coal mine work as
a foreman and then to reconsider the entirety of new
medical opinion evidence in light of that finding.” According
to the dissent, the ALJ may have discussed Killman’s job
duties, but he “failed to make the findings mandated by the
Board.” The dissent also pointed out that “none of the
physicians, including Dr. Cohen, demonstrated knowledge
of all the exertional requirements of claimant’s coal mine
employment, as set forth in the administrative law judge’s
decision and order and recounted in employer’s brief.” The
8                                               No. 04-2506

dissent cited Cornett v. Benham Coal Co., Inc., 

, 578 (6th Cir. 2000), for the proposition that “even a
‘mild’ respiratory impairment may preclude the performance
of the miner’s usual duties, depending on the exertional
requirements of the miner’s usual coal mining employ-
ment.” The dissent recommended that the Board vacate the
ALJ’s order and remand the case for further consideration.
  Upon Killman’s motion, the Board reheard the appeal en
banc. This time, four administrative appeals judges heard
the case; two voted to affirm the denial of benefits and two
dissented. Because a majority consisting of at least three
Board members would have been required to overturn the
panel’s decision, 20 C.F.R. § 802.407(d), this was insuffi-
cient to reverse the original panel. The prevailing opinion
offered little that was new, and the dissent reiterated the
problems with the inaccuracies and lack of attention to the
exertional requirements of Killman’s job. Killman then
petitioned for review in this court.


                             II
  In order to demonstrate changed circumstances, Killman
must show that he has become totally disabled. Midland
Coal Co. v. Director, Office of Workers’ Comp. Programs, 

(7th Cir. 2004). The regulations recognize four
ways for a claimant to do this. See 20 C.F.R.
§ 718.204(b)(2)(iv). Because Killman’s medical tests did not
produce qualifying results under three of the methods, only
one way remains for him: “if a physician exercising rea-
soned medical judgment, based on medically acceptable
clinical and laboratory diagnostic techniques, concludes
that a miner’s respiratory or pulmonary condition prevents
or prevented” him from performing his usual coal mining
work. 20 C.F.R. § 718.204(b)(2)(iv).
  This court reviews the ALJ’s decision, not the Board’s, “to
determine if it was rational, supported by substantial
No. 04-2506                                                  9

evidence on the record as a whole, and not contrary to law.”
Kennellis Energies, Inc. v. Hallmark, 

, 826 (7th
Cir. 2003). Killman criticizes the ALJ’s decision on a
number of grounds. He cites Poole v. Freeman United Coal
Mining Co., 

, 894 (7th Cir. 1990), for the
proposition that “the ALJ must first determine the nature
of the claimant’s usual coal mine work and then compare
evidence of the exertional requirements of the work with
medical opinions as to the claimant’s work capability.” Poole
reaches this conclusion in the limited context of an ALJ’s
characterization of medical opinions that do not explicitly
use the statute’s terminology of “total disability.” 

. There is no hard and fast requirement that an
ALJ make an explicit finding about the claimants’
exertional requirements, but Killman persuasively argues
that an ALJ may not reasonably rely on medical opinions
that are predicated on a misunderstanding of the claimant’s
job requirements.
  Whether the particular physicians’ opinions relied upon
by the ALJ constitute substantial evidence depends on
whether those physicians understood the work require-
ments that they presumed Killman could fulfill. The ALJ
refused to make a finding about their understanding of
what the job required, despite the Board’s mandate, writing
that the ALJ could not “substitute his opinion for that of the
physician, where the physician has an adequate understand-
ing of the Miner’s job duties . . .” (emphasis added). The
emphasized phrase must mean that the ALJ thought that
the physicians adequately understood Killman’s duties.
Unfortunately, we cannot tell definitely whether that is the
case, or what the ALJ thought the proper understanding of
those duties was. In order to eliminate doubt on this crucial
factual point, the ALJ should have summarized the testi-
mony on the requirements of Killman’s job and then directly
asked each doctor whether he could perform that work.
10                                              No. 04-2506

   We find it hard to believe that Drs. Tuteur, Dahhan,
and Renn fully appreciated the nature of Killman’s job, as
he described it in uncontradicted testimony. The physicians
who concluded that Killman was not disabled either mis-
stated Killman’s tasks or did not discuss them at all. The
ALJ noted repeatedly that the other physicians’ under-
standing of Killman’s exertional requirements was “as
complete as Dr. Cohen’s,” and that they had reviewed
Dr. Cohen’s summaries, but at least one of Dr. Cohen’s
summaries was inaccurate. Dr. Cohen wrote that Killman
was required to walk “60 feet every 20 minutes to one of the
8 face areas,” but Killman had testified that he had to walk
as much as 960 feet in that period of time. Dr. Cohen’s
erroneous characterization appeared in the report on which
Dr. Renn relied and which he quoted in his testimony, and
apparently it formed the basis of the other doctors’ under-
standing of the facts. Furthermore, even if the other doctors
had made it clear that they had reviewed all of Dr. Cohen’s
reports, we still have no way of knowing whether they
understood the underlying factual background. Logically, it
is likely that the doctors paid more attention to Dr. Cohen’s
medical opinion than to his account of the details of
Killman’s work history.
  It may be that the physicians would be just as sure that
Killman could walk 960 feet hunched over in a mine in 20
minutes as they were that he could walk 60 feet in a normal
posture. It may also be that the ALJ did not credit Dr.
Cohen’s diagnosis at all, which would defeat Killman’s
claim because Dr. Cohen was the only physician who found
him to be totally disabled, a requirement under 20 C.F.R.
§ 718.204(b)(2)(iv). If the ALJ’s opinion established either
of these possibilities, then it could be reasonable and well
supported. The ALJ, however, explicitly based his opinion
on the medical opinions that Killman was not disabled:
     As stated in my prior Decision and Order, after review
     of all of the recent medical evidence, including pulmo-
No. 04-2506                                               11

    nary function studies, arterial blood gas studies, and
    the medical reports of Drs. Tuteur, Renn, Dahhan,
    Baker, and Cohen, I find that the Claimant has not es-
    tablished total disability and has, therefore, not shown
    a material change in condition. My Decision is based on
    the reports of the physicians, the qualifications of the
    physicians, the reasoning of the physicians and the
    objective tests on which they relied. (Emphasis added.)
The ALJ’s refusal or inability to confirm that the physicians
understood Killman’s job casts doubt on the sufficiency of
those physicians’ opinions as a basis for his opinion. Be-
cause the ALJ’s order is not supported by substantial evi-
dence, we GRANT the petition for review, VACATE the Board’s
decision and REMAND this matter for further consideration.

A true Copy:
      Teste:

                        ________________________________
                        Clerk of the United States Court of
                          Appeals for the Seventh Circuit




                   USCA-02-C-0072—7-19-05
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