SYLLABUS

(This syllabus is not part of the opinion of the Court. It has been prepared by the Office of the Clerk for the convenience of the reader. It has been neither reviewed nor approved by the Supreme Court. Please note that, in the interests of brevity, portions of any opinion may not have been summarized).

Richard Lindquist v. City of Jersey City Fire Department (A-84-01)
    This is a companion case to Dennis Culbert v. City of Jersey City (A-92-01)

Argued September 23, 2002 -- Decided February 11, 2003

COLEMAN, J., writing for a unanimous Court.

    The issue on appeal is whether Richard Lindquist’s employment as a fireman for approximately twenty-three years caused or contributed to his development of pulmonary emphysema within the meaning of the occupational disease provisions of the Workers’ Compensation Act (the Act).

    Lindquist was employed as a full-time fireman with the City of Jersey City Fire Department (JCFD) from July 1972 until his retirement in January 1995. He was promoted to the rank of captain in 1979. During the first ten years of his employment, Lindquist responded to about 30 to 60 large fires per year, small one-room fires, car fires, and “dump” fires. Lindquist was given a self-contained breathing apparatus that he did not use very often. During larger fires, Lindquist was exposed to heavy smoke for up to forty-five minutes and was also exposed to fires involving burning chemicals, plastics, household cleaners, and propane.

    In 1982, JCFD provided all firefighters with the Scott mask, which provided oxygen or “purified air” to the user. Lindquist testified that the Scott mask did a good job of preventing fumes from entering the breathing passages, although he still inhaled smoke that seeped into the mask. He also frequently had to remove the mask either to give orders or to clear away moisture. From 1986 through 1992, Lindquist supervised the Hazardous Materials Unit, responding to both residential and industrial fires.

    Prior to beginning his job with JCFD, Lindquist had not suffered from any breathing, eyes, nose, or throat problems. He testified that while a firefighter with JCFD, he was taken to the hospital for smoke inhalation numerous times and, on other occasions, was given oxygen at the scene of a fire. Lindquist retired in 1995 at the age of forty-seven, due in part to an early buy-out offer and in part to health considerations. At the time of his retirement, Lindquist was less able to perform his responsibilities as a firefighter, particularly as captain, because his energy and normal breathing capacity had gradually diminished. He suffered from constant post-nasal drip and cough, shortness of breath, dry eyes, heart palpitations, and decreased breathing capacity. Lindquist began seeing a doctor in 1995 and was successfully treated with a bronchodilator twice or three times a week. Lindquist had smoked about three quarters of a pack of cigarettes per day for about twenty-two years until he quit smoking in either 1992 or 1994.

    Lindquist filed claims in the Division of Workers’ Compensation against JCFD, alleging occupational exposure to respiratory irritants while employed as a firefighter since 1972. Dr. Bernard Eisenstein, a heart and lung specialist who is Board Certified in internal medicine, testified at trial on Lindquist’s behalf. On January 16, 1995, Dr. Eisenstein performed a complete physical examination on Lindquist, including chest x-rays and pulmonary function tests. Based on the results of the examination and tests, Dr. Eisenstein concluded that Lindquist suffered from chronic obstructive pulmonary disease (COPD) in the form of emphysema. The doctor attributed Lindquist’s condition primarily to occupational exposure as a firefighter to fire, smoke, hazardous waste, combustion, and secondarily to cigarette smoking, but was unable to allocate exact percentages to each cause. Dr. Eisenstein concluded that, based on a reasonable degree of medical probability, Lindquist suffered thirty percent partial total permanent disability. On cross-examination, Dr. Eisenstein admitted that he could not cite to any studies in which non-smoking firefighters developed emphysema.

    Dr. Douglas Hutt, a physician Board Certified in internal, pulmonary, and critical care medicine testified on behalf of the fire department. At Lindquist’s physical examination on December 19, 1996, he told Dr. Hutt that he could do all of his normal activities although there was a subtle difference, and that his grandfather had died from emphysema. Dr. Hutt performed a complete physical examination, including a chest x-ray and pulmonary function tests. Based on his findings, Dr. Hutt concluded that Lindquist suffers from emphysema caused by cigarette smoking. Dr. Hutt was unable to testify with 100% certainty that some of the exposure as a firefighter could not in some way have contributed to the development of lung disease.

    The Judge of Compensation found that Lindquist’s occupational exposure materially contributed to the development of emphysema and awarded Lindquist a disability of thirty percent for emphysema. The Appellate Division reversed on appeal, concluding that the evidence was insufficient to establish medical causation between the employment and the emphysema.

    The Supreme Court granted certification.

HELD:     Richard Lindquist’s employment as a fireman with the City of Jersey City Fire Department caused or contributed to his development of pulmonary emphysema within the meaning of the occupational disease provisions of the Workers’ Compensation Act.

1. Occupational disease coverage under the Act has evolved from providing no coverage at all to the current statutory approach of providing a general definition of compensable occupational diseases, suggesting that there are numerous diseases that may be covered. The Act involves a trade-off whereby employees give up their rights to pursue common-law remedies in exchange for automatic entitlement to specific benefits whenever they suffer a compensable injury. Courts should use this “trade-off” rationale, as well as the science of the workplace, in its efforts to determine whether a disease is related to occupational exposure. Moreover, the Act is to be liberally construed; the Rules of Evidence to not apply in compensation proceedings; and the petitioner must prove both legal and medical causation. In New Jersey, it is enough to prove that the exposure to a risk or danger in the workplace was in fact a contributing cause of the injury. (Pp. 12-20)

2. The Rubanick standard governing the admissibility and reliability of medical causation evidence should be applied in workers’ compensation cases. Under that standard, when a scientific theory of causation has not yet reached general acceptance, it may be found to be sufficiently reliable if it is based on a sound, adequately-founded scientific methodology involving data and information of the type reasonably relied on by experts in the field. (Pp. 20-21)

3. In workers’ compensation cases, the appropriate standard for appellate review requires substantial deference be given to administrative determinations. The scope of appellate review is limited to whether the findings made could reasonably have been reached on sufficient credible evidence presented in the record, considering the proofs as a whole, with due regard to the opportunity of the one who heard the witnesses to judge their credibility. The petitioner has the burden of proving by a preponderance of the evidence that his environmental exposure was a substantial contributing cause of his occupational disease. (Pp. 22-23)

4. The standard articulated in Fiore for deciding occupational heart attack cases, whereby a petitioner must prove that his work exposure exceeded the exposure caused by personal factors such as cigarette smoking, is not applicable to non-heart cases. Rather, the controlling test is whether the exposure substantially contributed to the development or aggravation of the disease. Thus, Lindquist has the burden of proving by a preponderance of the evidence that his environmental exposure while fighting fires was a substantial contributing cause or aggravation of his emphysema. (Pp. 23-25)

5. The firefighters’ presumption provision of the Act provides that any condition or impairment of health of any member of a volunteer fire department caused by disease of the respiratory system shall be presumed to be an occupational disease unless rebutted by satisfactory proof. The Court can find no plausible reason why the Legislature would have intended to treat differently voluntary and paid firefighters who sustain the same pulmonary conditions after fighting the same fires. Therefore, the rebuttable statutory presumption of compensability also applies to paid firefighters. Numerous states provide a similar presumption. (Pp. 25-29)

6. The Court takes judicial notice of studies it reviewed that bolster the proposition that exposure to industrial pollutants at work can cause emphysema and that, although cigarette smoking is the most important risk factor for COPD, other risk factors, including environmental exposure, can cause emphysema. Moreover, other studies present strong scientific support for the theory that firefighting is a significant cause of lung disease. Thus, there is enough scientific data in support of Lindquist’s case to allow a Judge of Compensation to find in Lindquist’s favor. Given the current level of scientific knowledge about emphysema, Dr. Eisenstein’s testimony was not a subjective guess. There was sufficient credible evidence to support the Judge of Compensation’s decision granting Lindquist disability benefits. Lindquist sustained his burden of proof and the presumption in favor of compensability has not been rebutted. (Pp. 29-51)

    Judgment of the Appellate Division is REVERSED and the judgment of the Division of Workers’ Compensation is REINSTATED.

    CHIEF JUSTICE PORITZ and JUSTICES LONG, VERNIERO, LaVECCHIA, ZAZZALI and ALBIN join in JUSTICE COLEMAN’S opinion.

    



SUPREME COURT OF NEW JERSEY
A- 84 September Term 2001


RICHARD LINDQUIST,

    Petitioner-Appellant,

        v.

CITY OF JERSEY CITY FIRE DEPARTMENT,

    Respondent-Respondent.

Argued September 23, 2002 – Decided February 11, 2003

On certification to the Superior Court, Appellate Division.

Thomas W. Polaski argued the cause for appellant (Gary P. Sarlo, attorney).

John H. Geaney argued the cause for respondent (Capehart & Scatchard, attorneys).

    The opinion of the Court was delivered by

COLEMAN, J.
    The issue raised in this appeal is whether petitioner’s employment as a fireman for approximately twenty-three years caused or contributed to his development of pulmonary emphysema within the meaning of the occupational disease provisions of the Workers’ Compensation Act. Resolution of that issue requires us to decide how much workplace contribution is enough to trigger employer responsibility. The Judge of Compensation found that petitioner’s occupational exposure materially contributed to the development of emphysema. The Appellate Division reversed, finding that the evidence was insufficient to establish medical causation between the employment and the emphysema. We disagree and reverse.

I.
    Petitioner Richard Lindquist was employed as a full-time paid fireman with the City of Jersey City Fire Department from July 1972 until his retirement in January 1995. He was promoted to the rank of captain in 1979. Petitioner testified that during the first ten years of his employment, he responded to “30 to 60 large fires per year,” “small one-room” fires, car fires, and “dump” fires. When he began his job in 1972, each firefighter was given a self-contained breathing apparatus, “but it was just very new and people didn’t seem to use it until 1982.” Although petitioner was exposed to “heavy smoke” for up to forty-five minutes to an hour and a half during larger fires, he frequently did not use the apparatus. In respect of smaller fires, petitioner described the duration of exposure to smoke as follows:
Well, I guess basically outdoor fires you try to stay upwind if you can, but a lot of times they are grass fires that—down where Liberty State Park is now and the Liberty Science used to be, it is all grass area, which still has pretty much been an abandoned grass area that many times will catch on fire and the whole area would be lit, and you would be completely engulfed in smoke at the time, you couldn’t get away from it.

Some of the fires involved burning chemicals, plastics, household cleaners, and propane.
    In 1982, respondent distributed to all firefighters a protective device known as a Scott mask. The mask provided oxygen or “purified air” to the user. Petitioner testified that the Scott mask “did a pretty good job” of preventing fumes from entering the breathing passages. Nonetheless, he still inhaled smoke that seeped into the mask. He also frequently removed the mask to give orders to other firefighters and to clear moisture that accumulated on the mask.
    From 1986 to 1992, petitioner was assigned to supervise the Hazardous Materials Unit of the fire department. During that time, petitioner responded to both residential and industrial fires. The burning items consisted of plastics and chemicals, causing “much more toxic smoke than the ‘70s and ‘60s.” After 1992, petitioner returned to his position as captain.
    Prior to commencing employment with respondent, petitioner had not experienced any problems with breathing or with his eyes, nose, or throat. He testified that during his tenure with the fire department, he was taken to the hospital numerous times. On other occasions he was administered oxygen at the scene of a fire. He suffered from shortness of breath, heart palpitations, and weakness. After responding to a toxic dump fire in 1991, petitioner and “most of the other [firefighters]” were sent to the hospital to test for arterial blood gases. Although not hospitalized, petitioner experienced throat irritation, rapid breathing, and dizziness.
    Petitioner retired in 1995 at the age of forty-seven, due in part to an early buyout offer and in part to health considerations. At the time of his retirement, petitioner was less able to perform his responsibilities as a firefighter, and in particular as captain, because his energy and normal breathing capacity gradually had diminished. According to petitioner, he developed a “post nasal drip which would result in phlegm and coughing” that was “pretty constant” during his employment years. Now, those symptoms occur “[m]aybe two to three times a week.” He also suffers from dry eyes and shortness of breath and is no longer able to play basketball with his son or take long walks with his wife. He is able to walk only one quarter to one half of a mile “before [he begins] breathing heavily.” He cannot perform yard work or house work, such as “building sheds, [and] putting [together] decks,” without some difficulty. In 1995 or 1996, petitioner began seeing a physician who prescribed treatment with a bronchodilator one or two times per week. The treatment relieves petitioner’s symptoms “almost instantly.”
    Petitioner smoked approximately three-fourths of a pack of cigarettes per day for twenty-two years, stopping in 1992 or 1994. During the 1970s, he had a second job driving an oil truck. From 1982 through 1989, petitioner worked in residential construction in addition to his employment with the City of Jersey City. Shortly after leaving the fire department, petitioner became employed as a school bus driver.
    Dr. Bernard Eisenstein testified on petitioner’s behalf. Dr. Eisenstein specializes in heart and lung medicine and is Board Certified in internal medicine. He performed a complete examination of petitioner on January 16, 1995, to evaluate his pulmonary disability. In addition to the physical examination, Dr. Eisenstein performed a chest x-ray, and pulmonary function studies. The physical examination was “essentially negative, except [for] some areas of expiratory wheezing in the thorax.” However, the chest x-ray was “abnormal, [and] revealed increased bronchovascular markings with large lung volume, which . . . is compatible with emphysema.” The doctor explained that petitioner’s x-ray revealed “a hyperinflation . . . [indicating] . . . [that petitioner] has too much air in there [and] expiratory obstruction.” The results of the pulmonary function studies were “only a little abnormal.”
    Based on those tests, Dr. Eisenstein concluded that petitioner suffered from “chronic obstructive pulmonary disease in the form of emphysema.” He attributed petitioner’s condition primarily to occupational exposure as a firefighter to fire, smoke, hazardous waste, combustion, and secondarily to cigarette smoking. However, he was unable to allocate an exact percentage to each cause. Specifically, Dr. Eisenstein stated:
Firefighters get bronchitis, firefighters get emphysema, and in my experience of many years you can’t tell looking at an x-ray that this is due to cigarettes and this is due to work because of an occupation . . . . In other words, emphysema can be caused by many things, as I said, so there’s nothing characteristic as an occupation by a fireman, and they get a certain x-ray. There are certain changes seen in smoke inhalation, but he also can have these changes due to his exposures.

The doctor concluded that, “based upon a reasonable degree of medical probability,” petitioner suffered “30 percent of partial total” permanent disability. On cross-examination, Dr. Eisenstein admitted that he could not cite any studies in which non-smoking firefighters developed emphysema.
    In response to Dr. Eisenstein’s testimony, respondent presented the testimony of Dr. Douglas Hutt. Dr. Hutt is Board Certified in internal, pulmonary, and critical care medicine. During his examination of petitioner on December 19, 1996, petitioner informed Dr. Hutt that his primary symptom was a post-nasal drip that began one year after he retired from the fire department. Petitioner also told the doctor that “he really wasn’t very short of breath and could do all of his normal [activities] including normal walking and even walking upstairs and even doing some exercise including some mild jogging.” However, petitioner advised Dr. Hutt that he noticed “a subtle difference in his ability to exercise and he really wasn’t sure if this was related to some underlying medical condition or breathing problem or possibly because he was just getting older.” Dr. Hutt further testified that petitioner “did not think this was a major problem at the time” of the examination. He noted that petitioner “did not remember any long term symptoms that he had after any of the . . . exposures to any of the[] bad fires.” Additionally, petitioner told Dr. Hutt that “he smoked about three quarters of a pack [of cigarettes] a day for [twenty-two] years and that . . . his family pressured him to stop smoking about five years before [the] interview, but he did not stop because he was having breathing problems.” He also told Dr. Hutt that his brother and sister suffer from allergies and that his grandfather died from emphysema.
    Dr. Hutt performed a complete physical examination of petitioner including a chest x-ray, which revealed that petitioner’s lungs were over-inflated and “that the lung fields themselves are very, very big.” Finally, Dr. Hutt performed a complete set of pulmonary function tests. The results showed that petitioner “had some mild airflow obstruction,” that he suffers from “air trapping,” which means that petitioner retains almost three and a half liters of air in his lungs after a complete exhale, and that his diffusing capacity – the ability of the lungs to transfer oxygen from the air to the bloodstream – was moderately to severely reduced. Dr. Hutt stated that petitioner’s reduced diffusing capacity “correlates with destruction of lung tissue, lung injury, possibly scarring between the alveoli, which are the small air sacs, and the capillaries, which are small blood vessels” and “almost always [indicates] lung injury.”
    Based on the physical examination and the diagnostic testing, Dr. Hutt concluded that petitioner suffers from emphysema caused by petitioner’s cigarette smoking. According to the doctor, “even though only [twenty percent] of people that smoke cigarettes actually get emphysema, that number is [between seventy and eighty percent] higher if you have relatives that smoke cigarettes and get emphysema which is true in this patient’s family in his grandfather.” He concluded that petitioner suffered “approximately [thirty percent] pulmonary impairment.”
    Dr. Hutt acknowledged that many studies show that firefighters suffer from air flow obstruction and chronic bronchitis; however, he stated that “many of these studies . . . did not account for cigarette smoking” and “[n]one of the studies that [he had] seen . . . demonstrated conclusively or in any way that firefighters are [at] a greater risk for developing emphysema.” Thus he concluded that
[s]ince there’s no data to suggest firefighters with exposure on the job can develop emphysema, the patient definitely has emphysema, he has a smoking history, which is clearly the most common cause of emphysema, and there’s a strong family history of emphysema which increases your risk of developing emphysema from cigarette smoking, I believe that within a reasonable degree of medical probability that the patient’s emphysema is related to his cigarette smoking.

According to the doctor, out of approximately “a hundred” studies concerning firefighters and lung disease in general, none address emphysema but rather deal with air flow obstruction, chronic bronchitis, and other “more serious diseases.” He stated that he had not “seen [studies] that specifically mention emphysema as an increased risk when you factor out cigarette smoking in firefighters.” Dr. Hutt further testified that one significant difference between exposure to firsthand cigarette smoke and occasional exposure to smoke from fires is that cigarette smoking continuously exposes the airways to smoke, whereas occupational smoke exposure to the airways during fires is sporadic.
    In response to questions by the court, Dr. Hutt stated that “chemical exposures aren’t generally felt to cause emphysema.” He admitted, however, that he could not say “with 100% certainty . . . that some of the exposure that [petitioner] might have had on his job may [not] have in some small way contributed to the development of the lung disease.”
    The Judge of Compensation concluded that “petitioner’s occupation[al] disease is due in a material degree to the occupational exposures described” during the trial. The judge also determined that petitioner had suffered an “appreciable impairment of [his] ability to carry on the ordinary pursuits of his retirement lifestyle.” The judge awarded petitioner a disability of thirty percent for emphysema.
    On appeal, the Appellate Division reversed in an unpublished opinion, concluding that “the evidence of the causal connection between petitioner’s employment and his emphysema is insufficient to sustain the award.” The court noted that the primary requirement of N.J.S.A. 34:15-31 is that “petitioner’s disease be caused, to a material degree, by conditions in the workplace.” The second requirement of the statute, according to the panel, was “that the conditions contributing to the compensable disease must be characteristic of or peculiar to a particular trade.” The court concluded that the testimony of Dr. Eisenstein that “‘exposure to hazardous wastes played a significant role in causing [petitioner’s] emphysema, and the cigarettes . . . played a less dominant role,’” and his inability to assign a percentage to each cause, was “insufficient to show that petitioner’s work exposure exceeded the exposure caused by his smoking cigarettes.” (Emphasis added). The court also observed that Dr. Eisenstein relied “solely on petitioner’s general characterizations of his work exposures over the years and not on any existing medical, epidemiological or scientific studies establishing causation.”
    The court determined that petitioner’s argument that given his testimony and Dr. Eisenstein’s testimony, “‘respondent should have to come forward with definite medical evidence specifically excluding development of emphysema to one’s work as a firefighter,’” impermissibly “shift[ed] the burden of proof to respondent.” In the court’s view, “petitioner . . . bears the burden of showing by a preponderance of the evidence that his emphysema is caused in material degree by the conditions of his work environment.”
    We granted petitioner’s petition for certification, 171 N.J. 442 (2002), and now reverse.
II.
    Petitioner argues that the Appellate Division exceeded the scope of its appellate review and ignored testimony in the record that provided an evidentiary basis to support medical causation. He also contends that, absent any contrary legislative history, N.J.S.A. 34:15-43.2 should be interpreted as creating a presumption that his pulmonary disease arose from his employment as a paid firefighter. By implication, petitioner argues that if the presumption applies, his cigarette smoking and the death of his grandfather from emphysema did not rebut the presumption that petitioner’s emphysema is causally related to his exposure as a firefighter. Finally, petitioner contends that the higher standard adopted in Fiore v. Consolidated Freightways, 140 N.J. 452 (1995), with respect to dual causation should be limited to cardiovascular injuries and was applied improperly by the Appellate Division.
III.
    Preliminarily, the answers to all the issues presented must be informed by certain well-established general principles. When our Workers’ Compensation Act (Act), N.J.S.A. 34:15-1 to –128, originally was enacted in 1911, L. 1911 c. 95, it provided no coverage for occupational diseases. See Hichens v. Magnus Metal Co., 35 N.J.L.J. 327 (1912). The Act was amended thirteen years later to include occupational diseases. L. 1924, c. 124. Even then, only nine specifically enumerated diseases were covered: “anthrax, lead poisoning, mercury poisoning, arsenic poisoning, phosphorus poisoning, poisoning from all homologues and derivatives of benzine, wood alcohol poisoning, chrome poisoning, and caisson disease.” Millison v. E.I. du Pont de Nemours & Co., 101 N.J. 161, 175 (1985). Eventually, the Act was amended to “replace[] its limited list of specific-named occupational diseases with a definitional phrase, ‘compensable occupational disease.’” Ibid. (quoting L. 1949, c. 29). “The current definition of compensable occupational disease is [contained] in N.J.S.A. 34:15-31[(a)].” Millison, supra, 101 N.J. at 175. That subsection defines “compensable occupational disease[s]” as those diseases established by a preponderance of the credible evidence to have arisen “out of and in the course of employment, which are due in a material degree to causes and conditions which are or were characteristic of or peculiar to a particular trade, occupation, process or place of employment.” N.J.S.A. 34:15-31a (emphasis added). “Material degree” means “a degree [substantially] greater than de minimis.” Dwyer v. Ford Motor Co., 36 N.J. 487, 493-94 (1962); see also N.J.S.A. 34:15-7.2 (defining material degree as “an appreciable degree or a degree substantially greater than de minimis”).
Consequently, the history of occupational disease coverage under the Act has evolved from providing no coverage at all, to providing coverage for nine specifically enumerated diseases, to the current statutory approach of providing a general definition of compensable occupational diseases. That history “suggests either that the occupational disease risks of the workplace are too numerous to list separately or that in the future employees may contract occupational diseases, as yet unknown, that should nonetheless be compensated under the terms of the Act.” Millison, supra, 101 N.J. at 176.
    Another principle of general application is that the Act “involved a historic trade-off whereby employees relinquished their rights to pursue common-law remedies in exchange for automatic entitlement to certain, but reduced, benefits whenever they suffered injuries by [compensable] accident.” Id. at 174. See generally Richard A. Epstein, The Historical Origins and Economic Structure of Workers’ Compensation Law, 16 Ga. L. Rev. 775 (1982) (discussing the stages of development of workers’ compensation systems); Arthur Larson, The Nature and Origins of Workmen’s Compensation, 37 Cornell L.Q. 206 (1952) (describing history and characteristics of workers’ compensation). “[T]he quid pro quo . . . was that employees would receive assurance of relatively swift and certain compensation payments, but would relinquish their rights to pursue a potentially larger recovery in a common-law action.” Millison, supra, 101 N.J. at 174. That concept is sometimes referred to as the social compromise theory because of both the gain and the loss experienced by employees and employers alike. Ellen R. Peirce and Terry Morehead Dworkin, Workers’ Compensation and Occupational Disease: A Return to Original Intent, 67 Or. L. Rev. 649, 653 (1988).
Consequently, when the Division of Workers’ Compensation and appellate courts are called upon to decide whether a particular occupational disease is causally related to a particular employment, they should utilize the original bargain rationale for workers’ compensation and ergonomics to assist with the determination. Ergonomics refers to the applied science for the workplace that is broadly defined as “‘[t]he science relating to man and his work.’” Stasior v. National R.R. Passenger Corp., 19 F. Supp.2d 835, 847 (N.D. Ill. 1998) (quoting Dorland’s Illustrated Medical Dictionary 574 (28th ed. 1994)). Ergonomics and other applicable principles should be the lens through which the determination of whether emphysema is an occupational disease that is related to a firefighter’s exposure should be viewed.
    Still another well-established principle is “the social policy of liberally construing the Act,” which is social legislation designed “to implement the legislative policy of affording coverage to as many workers as possible.” Brower v. ICT Group, 164 N.J. 367, 373 (2000) (citing Saunderlin v. E.I. DuPont Co., 102 N.J. 402, 419 (1986)); Secor v. Penn Serv. Garage, 19 N.J. 315, 319 (1955). The same doctrine is applicable whether the claim involves an accidental injury or an occupational disease, or whether the focus is on a well-established or a modern health condition. But the bargain and the occupational disease statutory history contemplate that what constitutes a compensable occupational disease will be affected by many social and industrial factors that vary across time. At the very heart of the “original bargain . . . [is the notion that the burden of proof on claimants] would be easier . . . under workers’ compensation laws than under common law.” Jason M. Solomon, Note, Fulfilling The Bargain: How the Science of Ergonomics Can Inform the Laws of Workers’ Compensation, 101 Colum. L. Rev. 1140, 1156 (2001). Nonetheless, the doctrine of liberal construction does not extend to “‘the evaluation of credibility, or of weight or sufficiency of evidence.’” Oszmanski v. Bergen Point Brass Foundry, Inc., 95 N.J. Super. 92, 95 (App. Div. 1967) (quoting Page v. Federated Metals Div. 71 N.J. Super. 59, 63 (App. Div. 1961), certif. denied, 38 N.J. 302 (1962)), certif. denied, 51 N.J. 181 (1968) (emphasis omitted).
    It is also well-established that a successful petitioner in workers’ compensation generally must prove both legal and medical causation when those issues are contested. “[T]he question of whether an injury occurred ‘by accident’ is interwoven with the issue of medical causation.” Joy v. Florence Pipe Foundry Co., 64 N.J. Super. 13, 21 (App. Div. 1960) (citing 1 Larson, Workmen’s Compensation Law, §§ 38.82, 38.83 at 563-67), certif. denied, 34 N.J. 67 (1961). To establish causation in an occupational disease case, an employee must satisfy a two-part test by producing evidence to establish both (a) legal causation, and (b) medical causation. City of Tuscaloosa v. Howard, 318 So.2d 729 (Ala. Civ. App. 1975), overruled on other grounds, Gunter v. Borden, Inc., 680 So.2d 276 (Ala. Civ. App. 1996); In re Briggs, 645 A.2d 655, 659 (N.H. 1994). Medical causation means the injury is a physical or emotional consequence of work exposure. Stated another way, proof of medical causation means proof that the disability was actually caused by the work-related event. Hone v. J.F. Shea Co., 728 P.2d 1008, 1011 (Utah 1986). Proof of legal causation means proof that the injury is work connected. Kasper v. Board of Trustees of Teachers’ Pension and Annuity Fund, 164 N.J. 564, 591 (2000) (Coleman, J., concurring); In re Lockheed Martin Corp., 786 A.2d 872, 874-75 (N.H. 2001).
    It is sufficient in New Jersey to prove that the exposure to a risk or danger in the workplace was in fact a contributing cause of the injury. That means proof that the work related activities probably caused or contributed to the employee’s disabling injury as a matter of medical fact. Coleman v. Cycle Transformer Corp., 105 N.J. 285, 290-91 (1985). Direct causation is not required; proof establishing that the exposure caused the activation, acceleration or exacerbation of disabling symptoms is sufficient. See W. Page Keeton et al., Prosser and Keeton on the Law of Torts § 268 (5th ed. 1984). As one commentator has observed, “[t]he legal question is how much workplace contribution will be enough to trigger the employer’s liability under workers’ compensation.” Jordan Yospe, Note and Comment, U.S. Industries v. Director: “Claim” Versus “Condition” in the Analysis of Workers’ Compensation Cases, 12 Am. J.L. & Med. 273, 275 (1986). See also Douglas Danner & Elliot L. Sagall, Medicolegal Causation: A Source of Professional Misunderstanding, 3 Am. J.L. & Med. 303, 304-06 (1977).
    Another important principle is that the Rules of Evidence do not apply to workers’ compensation proceedings. N.J.S.A. 34:15-56 provides that when a Judge of Compensation decides a contested case, he or she “shall not be bound by the rules of evidence.” Ibid. Recently, we stated:
    Although the Rules of Evidence do not control the admission of evidence in workers’ compensation proceedings, it is well-settled that a judge of compensation’s determination must be based on competent evidence. Gilligan v. International Paper Co., 24 N.J. 230, 236 (1957); Andricsak[ v. National Fireproofing Corp.], 3 N.J. [466,] 471 [(1950)]; Helminsky[ v. Ford Motor Co.], 111 N.J.L. [369,] 373 [(E. & A. 1933)]; Friese[ v. Nagle Packing Co.], 110 N.J.L. [588,] 588 [(E. & A. 1933)]; Gunter[ v. Fischer Scientific Am.], 193 N.J. Super. [688,] 691 [(App. Div. 1984)]; Fagan v. Newark, 78 N.J. Super. 294, 307-08 (App. Div. 1963). The purpose of not requiring strict compliance with the Rules of Evidence is to simplify the nature of proofs that can be offered in workers’ compensation proceedings. Gunter, supra, 193 N.J. Super. at 691. Viewed in that context, the real issue presented is not whether evidence was admitted in violation of the Rules of Evidence, but whether there is substantial credible evidence in the record to support the judgment when the proofs are considered as a whole. Szumski v. Dale Boat Yards, Inc., 48 N.J. 401, 410, cert. denied, 387 U.S. 944, 87 [S. Ct.] 2077, 18 [L. Ed.2d] 1331 (1967); Close v. Kordulak Bros., 44 N.J. 589, 599 (1965); Goyden v. State Judiciary, Superior Court of New Jersey, 256 N.J. Super. 438, 446 (App. Div. 1991), aff’d o.b., 128 N.J. 54 (1992); Manzo v. Amalgamated Indus. Union Local 76B, 241 N.J. Super. 604, 609 (App. Div.), certif. denied, 122 N.J. 372 (1990). Due regard must be given to the opportunity of the one who heard the witnesses to judge their credibility. Szumski, supra, 44 N.J. at 410; Close, supra, 44 N.J. at 599; Goyden, supra, 256 N.J. Super. at 446.

[Reinhart v. E.I. DuPont De Nemours, 147 N.J. 156, 163-64 (1996).]

    Because the Rules of Evidence do not apply to these workers’ compensation proceedings, respondent did not seek a N.J.R.E. 104 hearing to challenge the admissibility of petitioner’s expert’s testimony with respect to medical causation. The Judge of Compensation found that expert’s testimony to be credible and found petitioner’s emphysema to be causally related to his employment exposure. Respondent has not waived its right to assert that the determination of the Judge of Compensation went so wide off the mark that a mistake must have been made that is correctable through appellate review.
    In workers’ compensation proceedings, as in the area of toxic tort litigation involving multiple causations or long-term exposure to toxic substances, it may not be possible scientifically for an injured person to prove decisively the medical cause of the injury. Faced with the need to accommodate the goals of our tort system when the scientific community was in disagreement, this Court adopted a less restrictive standard in Rubanick v. Witco Chemical Corp., 125 N.J. 421 (1991), for the admissibility of scientific evidence. That same standard is to be used in weighing the credibility of opinion evidence presented by experts. Given that the only significant distinctions between Rubanick and the present case are the forum and the quantum of damages recoverable, the Rubanick standard governing the admissibility and reliability of medical causation evidence should be applied in workers’ compensation cases as well. See, e.g., Kemp ex rel. Wright v. State, 174 N.J. 412 (2002) (applying Rubanick in non-toxic tort case).
    Rubanick, supra, dealt with occupational exposure to PCBs during the course of the plaintiff’s employment with the defendant. 125 N.J. at 425. The Court acknowledged that our Rules of Evidence governing the admissibility of expert evidence, formerly N.J.R.E. 19 and N.J.R.E. 56(2), now N.J.R.E. 702 and N.J.R.E. 703, are the starting point for determining whether the conventional general acceptance test of reliability should be the standard for the “admissibility of expert testimony relating to new or developing theories of causation in toxic-tort litigation.” Rubanick, supra, 125 N.J. at 432. Because “scientific knowledge [was] not ‘at a state of the art such that an expert’s testimony could be sufficiently reliable,’” the Court “fashion[ed] a broader standard for assessing the reliability of such evidence in [toxic-tort] litigation.” Id. at 432-33 (quoting State v. Kelly, 97 N.J. 178, 208 (1984)). The Court recognized that the need for a broader standard was due in part to “the extraordinary and unique burdens facing plaintiffs who seek to prove causation in toxic-tort litigation” and to “the extremely high level of proof required before scientists will accept a new theory.” Id. at 433. Consequently, in adopting a less restrictive standard, the Court held that
in toxic-tort litigation, a scientific theory of causation that has not yet reached general acceptance may be found to be sufficiently reliable if it is based on a sound, adequately-founded scientific methodology involving data and information of the type reasonably relied on by experts in the scientific field. The evidence of such scientific knowledge must be proffered by an expert who is sufficiently qualified by education, knowledge, training, and experience in the specific field of science. The expert must possess a demonstrated professional capability to assess the scientific significance of underlying data and information, to apply the scientific methodology, and to explain the bases for the opinion reached.

[Id. at 449.]
Finally, we turn to the appropriate standard of appellate review of determinations made in workers’ compensation cases. “Courts generally give ‘substantial deference’ to administrative determinations.” Earl v. Johnson & Johnson, 158 N.J. 155, 161 (1999) (quoting R & R Marketing, L.L.C. v. Brown-Forman Corp., 158 N.J. 170, 175 (1999)). In workers’ compensation cases, the scope of appellate review is limited to “whether the findings made could reasonably have been reached on sufficient credible evidence present in the record, considering the proofs as a whole, with due regard to the opportunity of the one who heard the witnesses to judge of their credibility.” Close, supra, 44 N.J. at 599 (citation and quotation marks omitted). Deference must be accorded the factual findings and legal determinations made by the Judge of Compensation unless they are “‘manifestly unsupported by or inconsistent with competent relevant and reasonably credible evidence as to offend the interests of justice.’” Perez v. Monmouth Cable Vision, 278 N.J. Super. 275, 282 (App. Div. 1994) (quoting Rova Farms Resort v. Investors Ins. Co., 65 N.J. 474, 484 (1974)), certif. denied, 140 N.J. 277 (1995).
    The petitioner has the burden to demonstrate by a preponderance of the evidence that his or her environmental exposure while fighting fires was a substantial contributing cause of his or her occupational disease. Such a petitioner is not required to “prove that the nexus between the disease and the place of employment is certain.” Magaw v. Middletown Bd. of Educ., 323 N.J. Super. 1, 11 (App. Div.), certif. denied, 162 N.J. 485 (1999); Laffey v. Jersey City, 289 N.J. Super. 292, 303 (App. Div.), certif. denied, 146 N.J. 500 (1996).

IV.
    First, we address whether the standard articulated in Fiore for deciding occupational heart-attack cases applies to this case. We agree with petitioner that the discussion in Fiore with respect to dual causes of cardiovascular injuries requiring a petitioner to prove that his or her work exposure exceeded the exposure caused by personal factors such as cigarette smoking does not apply to non-heart cases such as this pulmonary case. See Hellwig v. J.F. Rast & Co., 110 N.J. 37, 48 (1988) (tracing the progression of cardiac law that led to the enactment of N.J.S.A. 34:15-7.2 in 1979 and also stating that “the Legislature plainly expressed its intention to modify the holding in Dwyer”). In Fiore, the Court acknowledged that it was articulating a “standard to apply in a dual-causation case involving an occupational disease that allegedly has caused coronary-artery disease and an angina attack.” Fiore, supra, 140 N.J. at 464. A higher standard was adopted for occupational heart cases because N.J.S.A. 34:15-7.2 was enacted to increase a petitioner’s burden beyond that previously required by Dwyer, supra, 36 N.J. 487. Under Dwyer, there was an “assumption that employers take their employees as they find them” and that “‘ordinary work effort or strain’” was sufficient to satisfy the material-degree contribution requirement. Fiore, supra, 140 N.J. at 466-67 (quoting Dwyer, supra, 36 N.J. at 493). Dwyer defined material contribution to mean “some employment exertion capable medically of helping the attack—of furthering its progress.” 36 N.J. at 493-94. To make certain that the higher standard required by N.J.S.A. 34:15-7.2 was limited to cardiovascular and cerebrovascular cases, we stated that “a petitioner asserting an occupational heart-disease claim must show that the work exposure exceeds the exposure caused by the petitioner’s personal-risk factors.” Fiore, supra, 140 N.J. at 473 (emphasis added). Because Fiore does not apply to pulmonary cases, the Appellate Division should not have applied its holding here.
The controlling test to be applied in this case is whether the work exposure substantially contributed to the development or aggravation of emphysema. Petitioner had the burden to demonstrate by a preponderance of the evidence that his environmental exposure while fighting fires was a substantial contributing cause or aggravation of his emphysema. To satisfy that obligation, he was not required to prove that his work exposure exceeded the exposure caused by smoking cigarettes. Nor was he required to “prove that the nexus between the disease and the place of employment is certain” because that would violate the preponderance of the evidence standard. Magaw, supra, 323 N.J. Super. at 11; Laffey, supra, 289 N.J. Super. at 303.
In a case such as this one in which petitioner concedes that his personal risk factor played a significant role in developing emphysema, the Legislature has provided some relief to employers. When there are dual causes of an injury or disease, such as cigarette smoking and employment exposure, a 1979 amendment to the Act, L. 1979, c. 283, effective January 10, 1980, codified as N.J.S.A. 34:15-12(d), requires a credit to “be given [to] the employer or the employer’s insurance carrier for the previous loss of function and the burden of proof in such matter shall rest on the employer.” Ibid. The purpose of that amendment was to ameliorate the effect of prior law that an employer takes an employee as he finds the employee. Although that theory still pertains, the amendment permits a credit, regardless of whether or not the previous loss was work-related, “to encourage [the] hiring [of] workers with pre-existing disabilities.” Field v. Johns-Manville Sales Corp., 209 N.J. Super. 528, 530-31 (App. Div.), certif. denied, 105 N.J. 531 (1986); Abdullah v. S.B. Thomas, Inc., 190 N.J. Super. 26, 29-32 (App. Div. 1983).
V.
    Next, we address whether the statutory presumption contained in N.J.S.A. 34:15-43.2 applies to this case involving, as it does, a member of a paid fire department. That statute provides:
    [a]ny condition or impairment of health of any member of a volunteer fire department caused by any disease of the respiratory system shall be held and presumed to be an occupational disease unless the contrary be made to appear in rebuttal by satisfactory proof; providing

(a) Such disease develops or first manifests itself during a period while such member is an active member of such department; and

(b) Said member, upon entering said volunteer fire service, has or shall have undergone a medical examination, which examination failed or fails to disclose the presence of such disease or diseases; and

(c) Such disease develops or first manifests itself within 90 days from the event medically determined to be the cause thereof.

Any present member who did not undergo a medical examination upon entering said volunteer fire service, may undergo such examination within 180 days after the effective date of this act and in the event such examination does not disclose the presence of such disease or diseases, he shall thereafter be entitled to the benefits of this act.

[Ibid.]

    There is no legislative history indicating the Legislature’s intent when enacting the statute in 1964. Members of volunteer fire companies were already, at the time, covered by workers’ compensation laws. N.J.S.A. 34:15-43. Paid firefighters as public employees were also covered by the Act. Ibid. Because we can find no plausible reason the Legislature would have intended a difference when voluntary and paid firefighters sustained the same pulmonary conditions after fighting the same fire together, we hold that the presumption applies to paid firefighters as well. Further support for concluding that the presumption should not be restricted to volunteer firefighters is the fact that in 1987, the Legislature enacted a rebuttable presumption that cardiovascular and cerebrovascular injury or death to paid and volunteer firefighters sustained while performing fire suppression or medical emergency functions are compensable. L. 1987, c. 382, codified as N.J.S.A. 34:15-7.3. As will be shown later, at least thirty states have some form of a presumption for firefighters. If we have misperceived the Legislature’s intent, we invite the Legislature to reconsider this matter.
    The record does not fully inform us whether the statutory preconditions for the presumption have been met in this case. Assuming, however, that the presumption applies to this case and that subsections (a), (b) and (c) can be satisfied, the existence of such a rebuttable presumption is not dispositive of this appeal. To rebut the presumption, respondent presented evidence that petitioner smoked and had a family history of emphysema. Because the determination of whether respondent rebutted the presumption is intertwined with whether petitioner sustained his burden of proof on causation, we resolve both issues in petitioner’s favor in section VI of this opinion.
    Other jurisdictions have addressed the issue of statutory presumptions in favor of the firefighter in one form or another. For example, when Oregon adopted a disputable (rebuttable) presumption that firefighters’ heart and pulmonary conditions are related to the employment, the legislature “intended to give relief to firefighters because statistical studies indicated firefighters were much more likely to suffer from heart and lung diseases due to exposure to smoke and gases under strenuous conditions.” Wright v. State Accident Ins. Fund, 613 P.2d 755, 758 (Or. 1980). Similarly, when the State of Washington created a presumption, it “recognized that fire fighters as a class have a higher rate of respiratory disease than the general public.” Wash. Rev. Code § 51.32.185 Legislative Findings, 1987 c. 515.
    As noted in the Appendix to this opinion, our research discloses that thirty states have adopted a presumption that a firefighter’s pulmonary disease or condition is work related, generally following more than five years of such employment. Many states also require firefighters to have passed a medical examination at the beginning of their employment finding them free of pulmonary disease if they wish to invoke the presumption. Seventeen of those states’ presumptions relate to pension, special disability funds, and retirements. Thirteen states, including New Jersey, have presumptions covering workers’ compensation claims. At least one state legislature has been motivated by statistical studies indicating that firefighters are much more likely to suffer from heart and lung diseases due to exposure to smoke and gases under strenuous conditions. Other legislatures have reached the same result without reference to studies, stating that firefighters are “required to work in the midst of and are subject to heavy smoke fumes, and carcinogenic, poisonous, toxic or chemical gases from fires.” 40 Ill. Comp. Stat. Ann. 5/4-110.1. The fact that so many states have created various forms of presumptions of compensability for specified occupational conditions, suggests “(1) that a generalized causative link exists between the injury or disease and the workplace and (2) that such a causative link will be difficult to prove.” See Solomon, supra, at 1174 n.105 (quoting Joseph La Dou, M.D., et al., Cumulative Injury or Disease Claims: An Attempt to Define Employers’ Liability for Workers’ Compensation, 6 Am. J.L. & Med. 1, 21 (1980)).
    Because so many state legislatures have enacted various presumptions respecting the connection between firefighting and pulmonary and heart conditions, almost “a national consensus emerges regarding” the reliability of that proposition. Hamilton Amusement Ctr. v. Verniero, 156 N.J. 254, 270 (1998).

VI.
A.
    We now consider whether petitioner’s emphysema is medically related to his work exposure. The starting point is a statement of what that condition entails in general and a review of some pertinent studies, some of which focused on pulmonary conditions in firefighters. Emphysema is a “[c]hronic obstructive pulmonary disease (COPD), also called chronic obstructive lung disease[. It] is a term that is used for two closely related diseases of the respiratory system: chronic bronchitis and emphysema. In many patients these diseases occur together. . . . ” Div. of Lung Diseases & Office of Prevention, Educ. & Control, Nat’l Insts. of Health, Pub. No. 95-2020, Chronic Obstructive Pulmonary Disease 1 (3d prtg. 1995) (emphasis omitted) (hereinafter Nat’l Insts. of Health).
    Chronic bronchitis, one of the two major diseases of the lung grouped under COPD, is diagnosed when a patient has excessive airway mucus secretion leading to a persistent, productive cough. An individual is considered to have chronic bronchitis if cough and sputum are present on most days for a minimum of 3 months for at least 2 successive years or for 6 months during 1 year. In chronic bronchitis, there also may be narrowing of the large and small airways making it more difficult to move air in and out of the lungs. An estimated 12.1 million Americans have chronic bronchitis.

In emphysema there is permanent destruction of the alveoli, the tiny elastic air sacs of the lung, because of irreversible destruction of a protein in the lung called elastin that is important for maintaining the strength of the alveolar walls. The loss of elastin also causes collapse or narrowing of the smallest air passages, called bronchioles, which in turn limits airflow out of the lung. The number of individuals with emphysema in the U.S. is estimated to be 2 million.

In the general population, emphysema usually develops in older individuals with a long smoking history. However, there is also a form of emphysema that runs in families. People with familial emphysema have a hereditary deficiency of a blood component, alpha-1-protease inhibitor, also called alpha-1-antitrypsin (AAT). The number of Americans with this genetic deficiency is quite small, probably no more than 70,000. It is estimated that 1 in 3,000 newborns have a genetic deficiency of AAT, and 1 to 3 percent of all cases of emphysema are due to AAT deficiency.

The destruction of elastin that occurs in emphysema is believed to result from an imbalance between two proteins in the lung—an enzyme called elastase which breaks down elastin, and AAT which inhibits elastase. In the normal individual, there is enough AAT to protect elastin so that abnormal elastin destruction does not occur. However, when there is a genetic deficiency of AAT, the activity of the elastase is not inhibited and elastin degradation occurs unchecked. If individuals with a severe genetic deficiency of alpha-1-protease inhibitor smoke, they usually have symptoms of COPD by the time they reach early middle age. Deficiency of alpha-1-protease inhibitor can be detected by blood tests available through hospital laboratories. People from families in which relatives have developed emphysema in their thirties and forties should be tested for AAT deficiency. If a deficiency is found, it is critical for these people not to smoke.

Some scientists believe that nonfamilial emphysema, usually called “smoker’s emphysema,” also results from an imbalance between elastin-degrading enzymes and their inhibitors. The elastase-AAT imbalance is thought to be a result of the effects of smoking, rather than inherited as in familial emphysema. Some evidence for this theory comes from studies on the effect of tobacco smoke on lung cells. These studies showed that tobacco smoke stimulates excess release of elastase from cells normally found in the lung. The inhaled smoke also stimulates more elastase-producing cells to migrate to the lung which in turn causes the release of even more elastase. To make matters worse, oxidants found in cigarette smoke inactivate a significant portion of the elastase inhibitors that are present, thereby decreasing the amount of active antielastase available for protecting the lung and further upsetting the elastase-antielastase balance.

Scientists believe that, in addition to smoking-related processes, there must be other factors that cause emphysema in the general population since only 15 to 20 percent of smokers develop emphysema. The nature and role of these other factors in smokers’ emphysema are not yet clear.

[Id. at 2-4 (emphasis omitted).]
    Although “[c]igarette smoking is the most important risk factor for COPD . . . [o]ther risk factors include age, heredity, exposure to air pollution at work and in the environment . . . .” Id. at 1 (emphasis added). That means the National Institutes of Health has recognized that exposure to air pollutants at work can cause both chronic bronchitis and emphysema. Furthermore, “[s]cientists believe that, in addition to smoke-related processes, there must be other factors that cause emphysema in the general population since only 15 to 20 percent of smokers develop emphysema.” Id. at 4.
    Not only is it well known that industrial pollutants at work can cause or contribute to the development of emphysema, courts in New Jersey have awarded workers’ compensation for emphysema since the current general definition of occupational diseases became effective January 1, 1950. The first set of such cases was Masko v. Barnett Foundry & Mach. Co., 53 N.J. Super. 414, 423 (App. Div.), certif. denied, 29 N.J. 464 (1959), and Bucuk v. Edward A. Zusi Brass Foundry, 49 N.J. Super. 187, 193 (App. Div.), certif. denied, 27 N.J. 398 (1958), awarding compensation for emphysema and silicosis caused by pulmonary irritants.
    That same trend was continued into the next three decades. In Ort v. Taylor-Wharton Co., 47 N.J. 198, 201 (1966), the petitioner was awarded thirty percent of total permanent disability for pneumoconiosis and emphysema caused by exposure to foundry dust. Thereafter, he returned to work for the same employer in the same industrial environment that caused the pneumoconiosis to render him totally and permanently disabled. Id. at 202. In Taylor by Taylor v. Engelhard Indus., 230 N.J. Super. 245, 247 (App. Div. 1989), Solomon Taylor “was awarded [fifty-five percent] of total permanent disability for chronic bronchitis and pulmonary emphysema.” Those conditions were caused by the petitioner’s “expos[ure] to smoke, dust, fumes and other pulmonary irritants.” Ibid. In Gierman v. M & H
Mach. Co., 213 N.J. Super. 105, 107 (App. Div. 1986), Howard Gierman was awarded total and permanent compensation “as the result of his occupational exposure to pulmonary irritants while working for respondent. The disability was characterized as chronic, obstructive pulmonary disease including emphysema.” Ibid. In Brooks v. Bethlehem Steel Co., 66 N.J. Super. 135, 137 (App. Div.), certif. denied, 36 N.J. 29 (1961), compensation was awarded based on the petitioner’s exposure to smoke and fumes caused by his job as a burner-welder at the steel yard. Finally, another case finding emphysema related to an undescribed employment i