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

No. 07-1884
CONSOLIDATION COAL COMPANY,
                                                  Petitioner,
                              v.

DIRECTOR, OFFICE OF WORKERS’ COMPENSATION
PROGRAMS, UNITED STATES DEPARTMENT OF
LABOR, and DONALD E. BEELER,
                                        Respondents.
                    ____________
                Petition for Review of an Order
                 of the Benefits Review Board.
                        No. 06-BLA-0457
                      ____________
     ARGUED JANUARY 15, 2008—DECIDED APRIL 3, 2008
                      ____________


  Before EASTERBROOK, Chief Judge, and FLAUM and EVANS,
Circuit Judges.
  FLAUM, Circuit Judge. Donald Beeler is a 76-year-old ex-
smoker who spent a substantial portion of his career
working in mines. After being diagnosed with lung
disease, he applied for benefits under the Black Lung
Benefits Act. An Administrative Law Judge (“ALJ”)
reversed an earlier decision by the Department of Labor
and awarded Beeler benefits under the Act. The ALJ
weighed conflicting medical evidence and concluded that
2                                              No. 07-1884

Beeler’s lung disease arose, in part, from his coal mine
employment. Because the ALJ’s decision was supported
by substantial evidence, we affirm.


                      I. Background
  Beeler was an underground coal miner for at least
13 years, between 1961 and 1983. During that period of
time, he spent ten years with Consolidation Coal Company
(“Consolidation”) and was last classified as a section
foreman. When he was with Consolidation, he worked
five to seven days per week averaging 12-hour workdays.
His primary task was to make daily safety inspections
of the mine faces. He also worked with the crew, lifting
and carrying heavy supplies, helping with roof bolting,
operating the shuttle car, and assisting with repairs. On
average, he walked five to six miles per day. He was
exposed to coal dust on a daily basis. What complicates
this case is that Beeler was also a smoker. He started
smoking cigarettes at age 18 or 19, averaging one to one-
half pack per day at varying times. He quit at age 54,
after about 35 years of smoking.
  Beeler’s only medical condition is severe lung disease,
and he has testified that his breathing problems started
while he was working for Consolidation. His symptoms
included shortness of breath, the inability to lift heavy
objects, and the inability to walk any significant distance.
He was referred to a pulmonary specialist, Dr. Prabhu, in
1997. Dr. Prabhu gave Beeler inhalers (which he was
already taking), and enrolled him in a pulmonary rehabili-
tation program which he was unable to complete. Beeler
then began seeing Dr. Henkle, another pulmonary physi-
cian, in 2002. He ordered supplemental oxygen and
No. 07-1884                                                      3

prescribed nebulizer therapy. By 2005, Beeler was totally
dependant on the supplemental oxygen and was taking
three nebulizer treatments a day.
  Beeler filed a claim for black lung benefits in August
of 2001. He went through a Department of Labor exam-
ination with Dr. Drake, who found it reasonable that
his ailment—chronic obstructive pulmonary disease
(“COPD”)—was related to both his smoking history and
coal mining employment and that it disabled him.1 Never-
theless, the Department of Labor denied the claim on
August 12, 2002, finding that Beeler’s lung disease did
not qualify him for benefits. Beeler sought review before
an ALJ. Before this hearing, the parties developed addi-
tional evidence, including expert witness reports. The ALJ
ultimately awarded benefits to Beeler. He found the
presence of legal pneumoconiosis (i.e., COPD arising out
of coal mining employment) and total disability due to
the pneumoconiosis based on the medical opinion sub-
mitted by Beeler’s expert. The Benefits Review Board
affirmed the award of benefits on February 28, 2007.


                        II. Discussion
  Consolidation raises a single issue on appeal: whether the
ALJ’s determination that Beeler has pneumoconiosis
is supported by substantial evidence in the record. On


1
  Lung disease can be obstructive or restrictive. Obstructive
lung disease is characterized by an inability to fully exhale. This
leaves lungs hyperextended, and interferes with oxygen ex-
change. Restrictive lung disease is characterized by scarring
of the alveolar wall, which hinders oxygen from moving into
the bloodstream.
4                                              No. 07-1884

petition for review from a decision of the Benefits Review
Board, we examine the ALJ’s decision to determine if it
is rational, supported by substantial evidence, and
in accordance with the law. Peabody Coal Co. v. Shonk,

, 267 (7th Cir. 1990). We accept findings of
fact and corresponding conclusions when they are sup-
ported by substantial evidence in the record considered
as a whole. Meyer v. Zeigler Coal Co., 

(7th
Cir. 1990).
  In order to establish entitlement benefits, a miner must
show that he or she is totally disabled by pneumoconiosis
arising out of coal mine employment. Midland Coal Co. v.
Director, OWCP [Shores], 

, 491 (7th Cir. 2004).
Pneumoconiosis in this context can take two forms: clinical
and legal. Clinical pneumoconiosis is a “condition charac-
terized by permanent deposition of substantial amounts
of particulate matter in the lungs and the fibrotic reaction
of the lung tissue to that deposition caused by dust
exposure.” 20 C.F.R. § 718.201(a)(1). Legal pneumoconiosis,
which is what is at issue in this case, is a broader con-
cept. It is defined as any chronic lung disease arising out
of coal mining employment including COPD, emphysema,
and chronic bronchitis, which are characterized by air-
way dysfunction and are evidenced by a decrement in
the miner’s ability to exhale in a given amount of time.
30 U.S.C. § 902(b). Thus, Beeler had to prove in his pro-
ceedings below that his COPD was caused, at least in part,
by his work in the mines, and not simply his smoking
habit.
 There were several medical opinions given in this case.
Dr. Drake examined Beeler in 2002 as a part of the Depart-
ment of Labor pulmonary evaluation. He diagnosed
COPD—namely emphysema and chronic bronchitis—and
No. 07-1884                                            5

total disability. He concluded that the condition was
primarily due to smoking and found it reasonable that
occupation exposure was contributory given that smoking
could not account for the severity of the disability. In
addition, Dr. Prabhu and Dr. Cady wrote letters in sup-
port of Beeler’s black lung claim in 2002. Dr. Prabhu
diagnosed COPD and both doctors determined that
smoking history and coal dust contributed to the disease.
Dr. Henkle also examined Beeler in 2002. His diagnosis
was similar, and he concluded that coal dust exposure
could have contributed to the development of the em-
physema, as the smoking history was not particularly
strong. Then, Dr. Tuteur examined Beeler at Consolida-
tion’s request in 2003; he diagnosed severe COPD solely
due to smoking. He concluded that coal dust exposure did
not cause or contribute to Beeler’s lung disease, noting
that miners with no smoking history rarely have COPD,
while smokers have a one in five chance of developing
a severe obstruction. Dr. Renn reviewed the medical
records and issued a report in 2004 where he diagnosed
COPD due solely to smoking. Finally, Dr. Cohen reviewed
the medical records and issued a report of his findings
in 2005. He attributed the lung disease to both occupa-
tional exposure and smoking.
  The primary dispute in this case is whether the ALJ
considered and weighed all of the medical opinions that
address the etiology of Beeler’s chronic obstructive lung
disease. In order to qualify for benefits, Beeler had to
demonstrate that his lung disease was caused, at least in
part, by coal dust he inhaled while working as a miner.
Dr. Drake and Dr. Cohen concluded that the lung disease
was due to coal mine employment as well as smoking.
Dr. Tuteur and Dr. Renn decided that coal mine employ-
ment was not a cause. The ALJ gave decisive weight to
6                                             No. 07-1884

Dr. Cohen’s opinion and found the others, on a relative
basis, poorly reasoned. At the end of the day, “weighing
conflicting medical evidence is precisely the function of
the ALJ as fact-finder.” Poole v. Freeman United Min. Co.,

, 895 (7th Cir. 1990). The ALJ found Dr. Co-
hen’s opinion most persuasive because he carefully dis-
cussed the substantial body of scientific evidence docu-
menting the causal relationship between COPD and
occupational exposure demonstrating that a one pack
year smoking history is about equivalent to one year of
coal dust exposure. Dr. Cohen integrated this medical
evidence along with Beeler’s medical record to conclude
that coal dust exposure did contribute to his obstruction.
  Consolidation maintains that the ALJ was too dis-
missive of Dr. Tuteur and Dr. Renn’s medical opinions.
But the ALJ gave less weight to their opinions for sen-
sible reasons. We begin with Dr. Tuteur. First, the essence
of his opinion was a three sentence comment that pre-
sented a personal view that Beeler’s condition had to be
caused by smoking because miners rarely have clinically
significant obstruction from coal dust. This would lead
to the logical conclusion that Dr. Tuteur categorically
excludes obstruction from coal-dust-induced lung dis-
ease and would not attribute any miner’s obstruction,
no matter how severe, to coal dust. However, the De-
partment of Labor reviewed the medical literature on this
issue and found that there is consensus among scientists
and researchers that coal dust-induced COPD is clin-
ically significant. This medical authority indicates that
nonsmoking miners develop moderate and severe ob-
struction at the same rate as smoking miners. 65 Fed. Reg.
79,938. Second, Dr. Tuteur did not rely on information
particular to Beeler to conclude that smoking was the
only cause of his obstruction. Third, he did not cite a
No. 07-1884                                               7

single article in the medical literature to support his
propositions. Consolidation’s only counterargument here
is that it is possible to interpret Dr. Tuteur’s opinion as
being consistent with the proposition that coal dust expo-
sure can cause COPD in rare cases. But the Department of
Labor report does not indicate that this causality is merely
rare. And even if the causation is rare, Dr. Tuteur does not
explain why Beeler could not be one of these “rare” cases.
This flaw is endemic to the entire opinion, because Dr.
Tuteur did not appear to analyze any data or observations
specific to Beeler.
  The ALJ gave less weight to Dr. Renn’s report for simi-
larly rational reasons. The entirety of the opinion con-
sists of a list of diagnoses followed by a statement that
Beeler’s condition was the result of his smoking, not
coal dust exposure. There is no explanation or reasoning
demonstrated here that links the two elements—the
opinion is purely conclusory.
  Conversely, the ALJ had sensible reasons for giving
more weight to Dr. Cohen’s report. First, it was based on
objective data and a substantial body of peer-reviewed
medical literature that confirms the causal link between
coal dust and COPD. Second, he reviewed studies that
were even more recent than the aforementioned Depart-
ment of Labor study. Third, he linked these studies
with Beeler’s symptoms, physical examination findings,
pulmonary function studies, and arterial blood gas studies.
Finally, he explained that Beeler’s pulmonary function
studies showed “minimal reversibility after administra-
tion of bronchodilator” and that he had an “abnormal
diffusion capacity,” all of which is consistent with a
respiratory condition related to coal dust exposure.
   Consolidation raises two ancillary points as well. First,
it claims that the ALJ did not discuss the relevant CT
8                                             No. 07-1884

scan and medical records. This is not accurate. The ALJ
discussed all of the CT scan reviews (noting that they did
not find evidence of clinical pneumoconiosis) and con-
cluded, as he must, that they did not address causation.
With respect to medical records, the ALJ summarized
the evidence and indicated that the records were con-
sidered where relevant. Second, Consolidation contends
that the ALJ improperly shifted the burden of proof to
the employer to disprove that the claimant’s COPD was
not due to coal mine dust employment. However, it is
clear from the ALJ’s opinion that he appropriately evalu-
ated the conflicting medical opinion evidence congnizant
of the fact that the claimant bore the burden of estab-
lishing the existence of legal pneumoconiosis. The ALJ
properly found that Beeler satisfied his burden of proof
based on the reasoned and documented opinion of
Dr. Cohen, which outweighed the contrary reports of the
employer’s experts.
  In the end, Consolidation’s argument amounts to little
more than an attempt to ask this Court to reweigh the
evidence in the record. That is not our task. We do not
place the evidence back on the scale after the ALJ has
already done so. We simply examine whether the scale
was correctly calibrated. In this case, it was.


                    III. Conclusion
  For the foregoing reasons, we DENY the petition for
review and AFFIRM the judgment of the Benefits Review
Board.


                   USCA-02-C-0072—4-3-08