“SECRETARY OF LABOR,Complainant,v.KASTALON, INC.Respondent.OSHRC Docket No. 79-3561SECRETARY OF LABOR,Complainant,v.CONAP, INC.,Respondent.OSHRC Docket No. 79-5543_DECISION_Before: BUCKLEY, Chairman, RADER and WALL, Commissioners.BY THE COMMISSION:These consolidated cases are before the Occupational Safety and HealthReview Commission under 29 U.S.C. ? 661(j), section 12(j) of theOccupational Safety and Health Act of 1970, 29 U.S.C. ?? 651-678 (\”theAct\”). The Commission is an adjudicatory agency, independent of theDepartment of Labor and the Occupational Safety and HealthAdministration. It was established to resolve disputes arising out ofenforcement actions brought by the Secretary of Labor under the Act andhas no regulatory functions. See section 10(c) of the Act, 29 U.S.C. ?659(c).Kastalon, Inc., and Conap, Inc., manufacture polyurethane products.Among the chemicals they use in the manufacturing process is 4,4′-Methylene bis (2-chloroaniline), which is commonly called \”MOCA.\”[[1]]MOCA has been shown to cause cancer in laboratory animals. The Secretaryof Labor contends it must therefore be regarded as a cancer-causingagent (\”carcinogen\”) in humans and that exposure to it must be strictlycontrolled. The Secretary alleges that Kastalon and Conap violated theAct by failing to take adequate measures to protect their employees fromexposure to MOCA. In particular, the Secretary alleges that theemployers violated section 5(a)(1) of the Act, the so-called \”generalduty clause.\”[[2]] The Secretary also alleges that Conap violatedstandards governing the provision and use of personal protectiveequipment. For the reasons that follow, we conclude that the Secretarydid not prove that the employers violated the Act as alleged.IThe Act gives the Secretary two tools by which he can seek eliminationof workplace hazards. First, the Secretary can promulgate occupationalsafety and health standards and issue citations to employers who fail tocomply with those standards. 29 U.S.C. ? 655 (authority to promulgatestandards); 29 U.S.C. ? 654(a)(2) (employers are required to comply withstandards). Second, where no occupational safety or health standard isapplicable, the Secretary can attempt to obtain correction of aworkplace hazard through the general duty clause, which requires thatemployers provide workplaces free of recognized hazards that are causingor are likely to cause death or serious physical harm. The Act’slegislative history shows that Congress intended that the Secretarywould primarily rely on specific standards, rather than the broadmandate of the general duty clause, to seek the correction of workplacehazards. See S. Rept. No. 91-1282, 91st Cong., 2d Sess. (1970) at 9-10,reprinted in Senate Committee on Labor and Public Welfare, 92 Cong., 1stSess., Legislative History of the Occupational Safety and Health Act of1970, at 149-50 (Comm. Print, 1971); remarks of Rep. Steiger onconference bill, Id. at 1217 (\”general duty requirement should not beused set ad hoc standards.\”); Brisk Waterproofing Co., 73 OSAHRC 30\/E1,1 BNA OSHC 1263, 1264, 1973-74 CCH OSHD ? 16,345, p. 21,261 (No. 1046,1973). \”Reliance upon the general duty clause was discouraged because todo so would provide little advance warning of what specifically isrequired in order that employers could maintain a safe and healthfulworkplace.\” Id. Thus, the Commission has consistently held that theSecretary cannot rely on the general duty clause when a specificstandard applies to the facts. Id.; Daniel International, Inc., 82OSAHRC 23\/D3, 10 BNA OSHC 1556, 1982 CCH OSHD ? 26,033 (No. 78-4279, 1982).No occupational safety or health standard governs MOCA exposure. In1974, the Secretary did issue a detailed standard regulating workplaceuse of MOCA, but that standard was ruled invalid because the Secretaryhad not conformed to the Act’s requirements in promulgating it.Synthetic Organic Chemical Manufacturers Association v. Brennan, 503F.2d 1155 (3d Cir. 1974), cert. denied, 420 U.S. 973, reh’g denied, 423U.S. 886 (1975).[[3]] In early 1975,the Secretary again proposed thesame standard and held a hearing on the proposal. The polyurethaneindustry, through the Polyurethane Manufacturers Association, a tradeassociation that includes Kastalon and Conap among its members,participated in the hearing and urged the Secretary to adopt a morereasonable standard governing MOCA. However, the Secretary took noaction on the proposal. Beginning in 1976, the Secretary began to issuecitations alleging that employers were in violation of the general dutyclause for not taking adequate precautions against MOCA exposure.[[4]]The alleged violations in Kastalon’s and Conap’s workplaces occurred inlate 1978 and early 1979.The administrative law judges, James H. Alesia in Kastalon and Mary E.Cerbone in Conap, vacated the section 5(a)(1) citations primarilybecause they concluded that the Secretary was using the general dutyclause to circumvent both the court’s decision holding the original MOCAstandard invalid and the statutory requirements for promulgatingstandards. The judges noted that many of the abatement requirements theSecretary was seeking to have Kastalon and Conap implement were takendirectly from the invalid MOCA standard,[[5]] and they viewed thecitations as an attempt by the Secretary to enforce the invalid standardthrough the general duty clause.We are troubled, as were the judges, by the Secretary’s apparent attemptto enforce an invalidated standard through citations under the generalduty clause. As noted above, Congress contemplated that the Secretarywould place primary reliance on standards to achieve safe and healthfulworkplaces and envisioned that the general duty clause would be usedsparingly. Particularly in a situation like this, where a standard hasbeen proposed and rulemaking proceedings have been conducted, theSecretary’s failure to complete the rule-making, coupled with hisissuance of citations under the general duty clause, do not promote thegoals of \”fairness and mature consideration of rules of generalapplication\” that the Act’s rulemaking provisions were designed tofoster. See NLRB v. Wyman-Gordon Co., 394 U.S. 759, 764 (1969).On the other hand, the Secretary contends that he did not issue a MOCAstandard because he was simultaneously conducting a number of otherrulemaking proceedings that had higher priority. The Secretary alsomaintains that his failure to promulgate a standard should not denyemployees any protection that Congress intended them to have under thegeneral duty clause. We recognize that the Secretary has discretion totake into account other rulemaking proceedings in which he is engaged insetting a timetable for issuing a particular standard. Public CitizenHealth Research Group v. Auchter, 702 F.2d 1150, 1157-58 (D.C. Cir.1983). However, we question whether this discretion coupled with theSecretary’s aim of protecting employee health justifies the use of thegeneral duty clause in effect to side step the procedural requirementsof the Act and impose the requirements of the invalidated MOCA standardon employers. We need not, however, decide whether the Secretaryexceeded the limits of his discretion here. Assuming arguendo that thegeneral duty clause citations were properly issued, we conclude that theSecretary failed to prove that Kastalon and Conap violated section5(a)(1), and we vacate the citations on that basis.IIKastalon and Conap both use MOCA as a raw material in the manufacture ofpolyurethane products. Both companies purchase MOCA in the form of drypellets about the size of kernels of corn. To manufacture polyurethane,MOCA is first melted and then mixed in proper proportions with anotherchemical, referred to as a prepolymer, to form liquid polyurethane. Theliquid polyurethane is then molded into the shape of the part beingfabricated. Employee contact with MOCA can occur when the chemical isremoved from its shipping container, when it is heated in order to meltit, and when the molten MOCA is mixed with the prepolymer. Spills ofMOCA can also lead to employee contact.By the time of the alleged violations, Conap had eliminated humancontact with MOCA in most of its MOCA-handling operations. Most of thepolyurethane products Conap fabricated were made in the following way. Aclosed drum of MOCA was placed in an enclosed chamber, with access tothe MOCA provided through rubber gloves in one side of the the chamber. A worker would place his hands in the gloves, remove the top of the MOCAbarrel, and insert a vacuum tube. The dry MOCA would be sucked throughthe vacuum tube into a MOCA melter, from which it would be transferredwithout human contact to an automatic process control (\”APC\”) machine.The melted MOCA would be automatically mixed with the prepolymer in theAPC machine, which would then discharge the liquid polyurethane intomolds. Conap also used other processes in which the possibility ofemployee contact with MOCA was present, but it was in the process ofautomating some of these processes. The company also provided personalprotective equipment to minimize employee contact with MOCA.Kastalon used much less MOCA than did Conap, and its MOCA-handling wasnot automated, as was Conap’s. However, after the MOCA was transferredfrom its original shipping container, all handling of MOCA was doneunder a ventilated laboratory hood. Kastalon also provided personalprotective equipment to minimize employee contact with the chemical androtated the employees who handled MOCA, thus limiting the amount of MOCAto which any individual employee was exposed.Kastalon’s and Conap’s polyurethane manufacturing operations resulted inemployee exposure to MOCA. MOCA is readily absorbed through the skin,and the handling of MOCA in Kastalon’s and Conap’s plants resulted insome degree of employee skin contact with the chemical. Because it hasan extremely low vapor pressure, MOCA does not present a hazard ofairborne contamination except to the extent that MOCA dust is generatedand becomes airborne. The record indicates that certain operationsperformed in Kastalon’s and Conap’s plants did generate visiblequantities of airborne MOCA dust for brief periods of time. TheSecretary’s industrial hygienist measured the concentration of airborneMOCA to which two Kastalon employees were exposed. These measurementsshowed 8-hour time weighted average concentrations of 9.9 and 12micrograms per cubic meter. Wipe samples of surfaces in Kastalon’s plantshowed that MOCA was present on the surfaces in amounts ranging from 87to 1830 micrograms per 100 square centimeters of surface area. InConap’s plant, airborne samples, and wipe samples from employees’ skintaken during the inspection yielded no detectable amounts. However,measurements of the concentration of MOCA in the urine of certain ofConap’s employees showed that the employees were absorbing measurableamounts of MOCA. These measurements showed concentrations of MOCAranging from 100 to 620 micrograms per liter of urine.To prove that an employer violated section 5(a)(1), the Secretary mustshow (1) that a condition or activity in the employer’s workplacepresented a hazard to employees, (2) that the cited employer or theemployer’s industry recognized that hazard, (3) that the hazard waslikely to cause death or serious physical harm, and (4) that feasiblemeans existed to eliminate or materially reduce the hazard. PelronCorp., 86 OSAHRC ____, 12 BNA OSHC 1833, 1986 CCH OSHD ? 27,605 (No.82-388, 1986); Davey Tree Expert Co., 84 OSAHRC 11\/D11, 11 BNA OSHC1898, 1984 CCH OSHD ? 26,852 (No. 77-2350, 1984).The threshold question in this case is whether the Secretary proved thatKastalon’s and Conap’s employees were exposed to a hazard. The Secretaryargues that MOCA must be regarded as a human carcinogen based onexperiments in which cancer was induced in laboratory animals, and thatany amount of exposure to a carcinogen is hazardous. Although the recorddoes not support a finding that MOCA is a known human carcinogen, itdoes establish that MOCA may be carcinogenic in man and therefore itshould be considered a suspect human carcinogen. Expert witnesses forboth sides testified to that effect. The mere fact that a chemical is asuspect human carcinogen, however, does not establish that a hazardexists within the general duty clause of the Act. In order to establishthe existence of a hazard, the Secretary cannot simply show that asuspect human carcinogen is present in the workplace or that employeesare exposed to it in some detectable amounts. The Secretary must provethat the amount to which employees are exposed presents a significantrisk of harm.Our conclusion that the evidence must establish that a significant riskof harm exists at Kastalon’s and Conap’s workplaces rests on the SupremeCourt decision in Industrial Union Department, AFL-CIO v. AmericanPetroleum Institute, 448 U.S. 607 (1980) (\”the Benzene Case\”). In theBenzene Case, the Supreme Court concluded that an OSHA standardgoverning exposure to benzene was invalid. Benzene is a chemical thathas long been known to cause nonmalignant diseases in sufficiently largeexposures. In order to protect against these diseases, the Secretaryadopted a standard in 1971 limiting exposure over an 8-hour time periodto an average of 10 parts per million (\”ppm\”).[[6]] 448 U.S. at 617.In the 1970’s, evidence began to accumulate that benzene can causeleukemia as well as the nonmalignant diseases it had previously beenknown to cause. The Secretary thereupon initiated notice-and-commentrulemaking proceedings aimed at lowering the permissible exposure limit.He proposed, and ultimately adopted, a standard limiting employeeexposure to an 8-hour average of 1 ppm. In reducing the permissibleexposure by a factor of ten, the Secretary proceeded on the assumptionthat no safe limit for exposure to a carcinogen could be established. Hebelieved that the Act required him to establish as a permissibleexposure limit the lowest limit that industry could feasibly achieve inthe absence of evidence establishing that a higher limit was safe.Concluding that 1 ppm was a feasible limit, the Secretary establishedthat as the permissible exposure limit. 448 U.S. at 623-26.The Supreme Court concluded that the new standard was invalid becausethe Secretary had not justified reducing the permissible exposure limitfrom 10 ppm to 1 ppm. The Court primarily criticized the Secretary’sreasoning that the permissible exposure limit had to be set at thelowest feasible level if a safe level of exposure could not beestablished. The Court noted that Congress did not intend the Act tocreate risk-free workplaces and it therefore concluded that aprecondition to the adoption of a standard under section 6(b) of the Actwas a finding that workers were exposed to a significant risk of harmunder the conditions currently existing in the workplace. 448 U.S. at642. In issuing the new benzene standard, the Secretary had not made afinding that benzene posed a significant risk at the preexistingpermissible exposure limit of 10 ppm. Instead, the Secretary had foundthat the evidence presented in the rule-making record did not establishany level as safe, and therefore he presumed that exposure in any amountwas hazardous. This finding, under the Court’s reasoning, wasinsufficient to permit a new standard to be promulgated. Id. at 659.The Court’s observation that Congress did not intend for the Act tocreate risk-free workplaces applies equally to enforcement of thegeneral duty clause as well as to the Secretary’s authority to issuestandards. Congress intended that the general duty clause would provideprotection when no standard had yet been adopted, not provide protectionthat would go beyond what standards could permissibly provide. Indeed,the general duty clause is more restrictive than standards, for itapplies only to hazards that are recognized by an employer or theemployer’s industry and that are causing or are likely to cause death orserious physical harm. Thus, in order to prove the existence of a hazardwithin the meaning of the general duty clause, the Secretary cannotmerely show that there may be some degree of risk to employees. He mustshow, at a minimum, that employees are exposed to a significant risk ofharm. Cf. Anoplate Corp., 86 OSAHRC, _____,12 BNA OSHC 1678, 1681, 1986CCH OSHD ? 27,519, p. 35,680 (No. 80-4109, 1986) (Secretary must showsignificant risk when standard requires proof of a hazard as an elementof the alleged violation).[[7]]The Secretary contends that the concept of \”significant risk\” is alreadysubsumed in the general duty clause in the requirement that a hazard be\”recognized.\” He argues that the recognition requirement \”encompassesnotions of what workplace conditions reasonably prudent persons believeshould be guarded against,\” and thus assures that conditions that do notpresent a significant risk will not be subject to section 5(a)(1).Implicit in this argument is the suggestion that any precautionsemployers take to protect the health or safety of their employees mustbe directed at a significant risk of harm or the employers would nottake them. We do not believe this is a valid premise. Employers maydecide to limit the exposure of their employees to chemicals of unknowntoxicity or to take other precautions against injury or illness out ofan abundance of caution rather than a belief that the absence of suchprecautions would expose employees to a significant risk of harm. Themere fact that employers take certain precautions does not prove thatthose precautions are required by an occupational safety or healthstandard or by the general duty clause. The Commission and courts haveconsistently held that it would be inappropriate to base a finding thata hazard exists solely on evidence that an employer has taken certainprecautions because to do so would dissuade employers from takingvoluntary protective measures beyond those the law requires. GeneralMotors Corp., GM Parts Division, 84 OSAHRC 23\/A2, 11 BNA OSHC 2062,2066, 1984 CCH OSHD ? 26,961, p. 34,611 (No. 78-1443, 1984). aff’d, 764F.2d 32 (1st Cir. 1985); Cotter & Co. v. OSHRC, 598 F.2d 911, 915 (5thCir. 1979); Diebold, Inc. v. Marshall, 585 F.2d 1327, 1338 (6th Cir.1978); Cape & Vineyard Division v. OSHRC, 512 F.2d 1148, 1154 (1st Cir.1975). Accordingly, we reject the Secretary’s argument that the\”recognition\” element of section 5(a)(1) eliminates the need for him toshow that employees are exposed to a significant risk of harm in orderto show that a hazard exists within the meaning of the general dutyclause. We turn to whether the Secretary met his burden of proof in thiscase.IIIMOCA is a member of a family of chemicals referred to as aromaticamines. Several members of this group are known to cause cancer inhumans. To date, there is no evidence directly linking MOCA exposure tocancer in humans.[[8]] However, there is typically a long latencyperiod, often 30 to 40 years, between human exposure to a carcinogen andthe onset of cancer. Therefore, the absence of direct evidence that achemical is a human carcinogen, particularly as when here the chemicalhas not been in use for a long period of time, is inconclusive evidencethat the chemical is not a human carcinogen.Because of the long latency period between human exposure to acarcinogen and the onset of cancer, humans may be exposed to a chemicalfor many years before it can be definitively established that thechemical is carcinogenic. See, e.g., Society of the Plastics Industry v.OSHA, 509 F.2d 1301, 1305-06 (2d Cir. 1975) (vinyl chloride, which beganto be used in 1939, was found to be a carcinogen in the early 1970’s).In order to determine whether a chemical may be a human carcinogenbefore cases of cancer occur in humans, scientists perform experimentsin which they determine whether laboratory animals exposed to thechemical contract cancer. Their supposition is that chemicals thatinduce cancer in small mammals are also likely to be human carcinogens.MOCA has been the subject of several laboratory experiments in which thechemical induced cancer in three species of laboratory mammals: rats,mice, and beagles. The beagle study. performed by du Pont, demonstratedthat beagles who ingested MOCA contracted bladder cancer.[[9]] Expertwitnesses for both sides, Dr. John D. Scribner for the Secretary and Dr.George T. Bryan for the employers, agreed that the induction of bladdercancer in dogs strongly indicated that MOCA would also cause bladdercancer in humans. Dr. Scribner noted that other aromatic amines –benzidine, beta napthalamine, and 4 amilnobiphenyl — were known tocause bladder cancer in both dogs and humans. Dr. Bryan, a qualifiedexpert in carcinogenicity, had been engaged by the PolyurethaneManufacturers Association (\”PMA\”) to evaluate the available dataregarding MOCA, to advise its members on how to deal with MOCA, and toassist it in the rule-making proceedings initiated by the Secretary. Hebelieved that MOCA should be strictly regulated based on the studiesshowing that it induced cancer in laboratory animals. He stated that \”nolevel of exposure to a carcinogenic substance, however low it may be,can be scientifically established . . . to be a ‘safe level’ for humans.\”The Secretary contends that these statements by Dr. Bryan constituteevidence that an expert familiar with the polyurethane industryrecognized that MOCA is hazardous in any detectable exposure. Howeverwhether Dr. Bryan’s statements show that the polyurethane industry\”recognized\” a hazard is not our initial inquiry. The first question wemust address is whether the evidence shows any hazard at all; only thendoes the question of whether the hazard is \”recognized\” arise. Dr.Bryan’s statement that no level of exposure to a carcinogen can bescientifically established as \”safe\” does not prove that Kastalon’s andConap’s employees were exposed to a significant risk of harm under theconditions present in their workplaces.[[10]] The central point of theBenzene Case is that a significant risk at any level of exposure cannotbe presumed simply because a \”safe\” level of exposure cannot beestablished. 448 U.S. at 652-53. The Court rejected the Secretary’spolicy that, \”in the absence of definitive proof of a safe level, itmust be assumed that any level above zero presents some increased riskof cancer.\” Id. at 635-36 (emphasis by the Court, footnotes omitted).The Secretary cannot impose this discredited policy on an industry underthe general duty clause simply by finding an expert familiar with theindustry to testify that a safe level cannot be established for acarcinogen used by the industry. The absence of a \”safe\” level does notmean that there is a \”significant risk\” of harm at any particular level.As the Court made plain, risk-free workplaces are not required by the Act.The Secretary also argues that industry recognition of a hazard shouldbe predicated on advice given by Dr. Bryan to the PMA that its membersshould \”insure\” that employees are not exposed to detectable quantitiesof MOCA. This is simply the \”no safe level\” argument in another guise.Moreover, we do not agree with the Secretary’s interpretation of thecontents of the letter Dr. Bryan wrote to the PMA. The relevant portionof the letter states:Tumors of the bladder frequently are produced in animals fed chemicalsof the class called aromatic amines. Representative chemicals of thisclass are 2-naphthylamine, 4-aminobiphenyl, and benzidine. Each of thesechemicals are recognized as human urinary bladder carcinogens, and eachhas caused urinary tract tumors in dogs when fed. These tumors arequalitatively similar to those produced by MOCA in dogs. Finally, MOCAis a member of the aromatic amine class of chemicals.I believe that these data will have a substantial impact on the MOCAregulation proceeding. They demonstrate that MOCA possesses the samecarcinogenic potential as other recognized human carcinogens. Theinference that most will draw is that individuals working with MOCA areat definite risk of developing cancer. This inference might be bluntedsomewhat by a demonstration that under conditions of working with MOCApotentially exposed persons do not incorporate MOCA into their bodies,or excrete it or any of its metabolites into body fluids in detectablequantities. Additional evidence desirable in support of the view thatMOCA does not represent an actual hazard would be a demonstration thatno detectable quantities of MOCA are present in the work environmentunder conditions of usual usage. If these are not possible or feasible,then MOCA must be dealt with as a known animal carcinogen and as apotential human carcinogen.This letter reiterates Dr. Bryan’s consistently expressed view that MOCAshould be regarded as a suspect human carcinogen based on itscarcinogenic activity in animals. Although it says that a showing thatemployees are not exposed to detectable quantities of MOCA would negateany inference that a hazard exists, Dr. Bryan did not state that ahazard exists whenever there are detectable levels of MOCA. Also,contrary to the Secretary’s argument, the letter does not adviseemployers that employees should not be exposed to any detectablequantity of MOCA.The Secretary also argues that industry recognition of a hazard wasshown because industry generally recognized the need to take precautionsagainst MOCA exposure. He particularly relies on recommended precautionsfor MOCA handling published by du Pont, which was then the chemical’sprimary manufacturer. Du Pont included with each barrel of MOCA it solda booklet entitled \”Safe Handling of MOCA Urethane Curative.\” Thisbooklet recommended that MOCA users take certain precautions theSecretary alleges Kastalon and Conap failed to take. The Secretary alsopoints out that the polyurethane industry, through the PolyurethaneManufacturers Association, was urging both the federal government andthe State of California to adopt MOCA standards and was informing itsmembers, through semiannual meetings and in publications, of the need tocontrol MOCA exposures. These PMA activities, the Secretary argues, showthat the polyurethane manufacturing industry recognized the need forcontrolling exposure to MOCA. The Secretary further argues that hazardrecognition is shown by evidence that individual companies in thepolyurethane industry took certain precautions when handling MOCA.The Secretary’s argument demonstrates that the evidence of MOCA’scarcinogenicity is sufficiently compelling that reasonable peoplerecognize it is necessary to handle the chemical carefully. Thatevidence does not, however, show that the levels of MOCA to whichKastalon’s and Conap’s employees were exposed presented a significantrisk of harm. An industry’s general recognition that a chemical may becarcinogenic in man and that exposure to it should be controlled doesnot eliminate the need for the Secretary to prove that a particularemployer’s employees are exposed to dangerous levels in order to prove aviolation of the general duty clause.[[11]]IVIn order to establish a significant risk in a section 5(a)(1) caseinvolving a carcinogen, the Secretary must show the probability thatemployees will contract cancer under the conditions present in theworkplace. This is consistent with the Supreme Court decision in theBenzene Case. There the Court ruled that the Secretary must establish asignificant risk exists through a body of reputable scientific thought.It noted that animal studies, epidemiological evidence and workermortality rates could be used to establish the existence of asignificant risk. 448 U.S. at 656 & n. 64.The only evidence in the record which tends to show the probability ofemployees contracting cancer from exposure to MOCA is a quantitativerisk assessment prepared by Dr. John D. Scribner, an expert in chemicalcarcinogenesis. A quantitative risk assessment is an estimate of theprobability that humans will contract a disease. It is often based onevidence gathered from animal tests.[[12]]Dr. Scribner’s quantitative risk assessment relied heavily on evidencegathered in the du Pont study that showed MOCA induced cancerous tumorsin beagles. In that study, six dogs were fed MOCA in their daily diet inan amount equal to 14 milligrams per kilogram of body weight. One dogdied early in the study. The remaining five contracted lower urinarytract cancers–four bladder tumors and one tumor of the ureter–after 8to 9 years. Of a group of six control dogs, none contracted cancerwithin that same time span. Dr. Scribner calculated that each exposeddog had received a total lifetime dose of 14 grams of MOCA per kilogramof body weight, and he observed that this dose produced a 100% chance ofcontracting cancer, as all the exposed dogs had done so.Dr. Scribner then attempted to correlate this information with evidenceof human exposures. He noted that a MOCA rat study at the NationalInstitute for Occupational Safety and Health showed that the ratsexcreted in their urine about 0.03% of the MOCA they consumed, and thatthis was approximately the same as the percentage of benzidine that ahuman excreted when benzidine was applied to his skin. Dr. Scribnertherefore estimated that the total amount of MOCA to which a person wasexposed in a day would be about 3000 times the amount the personexcreted in his urine that day. Assuming that a worker excreted 50micrograms of MOCA per day in his urine and worked 250 days per year,Dr. Scribner calculated that the worker would receive a total dose of 14grams per kilogram of body weight after 39 years. As this was the totaldose at which the beagle dogs exhibited a 100% incidence of tumors, Dr.Scribner postulated that the worker would be at a 100% risk ofcontracting cancer after 39 years. To buttress his estimate, Dr.Scribner noted that MOCA and benzidine were about equally potent atproducing cancer in dogs, and that a study had shown that 50% of workershad contracted bladder cancer after a total exposure to benzidine of 5grams per kilogram of body weight. Assuming that MOCA and benzidineproved to be equally potent in humans, as they were in dogs, the humanexperience with benzidine demonstrated that workers exposed to similaramounts of MOCA as benzidine would experience a significant risk ofcontracting cancer.The employers’ expert, Dr. Bryan, criticized the central assumptionunderlying Dr. Scribner’s risk assessment; that the quantitativeresponse of humans and dogs to MOCA would be equal. Dr. Bryan believedthat quantitative estimates of the risk to humans from animal responsesto a carcinogen could not be made with any reasonable degree ofscientific certainty. He noted that it was difficult to obtain the samequantitative response even in different experiments with animals of thesame species due to the many variables that enter into such experiments.It was even more difficult to extrapolate from laboratory animals tohumans. Dr. Bryan stated, for example, that the animals used in cancerexperiments are genetically similar (homogeneous) while a typical groupof exposed workers would be genetically mixed (heterogeneous). Becausean animal’s or human’s genetic structure greatly affects its response toa carcinogen, one cannot assume that a heterogeneous group of humanswill respond quantitatively in the same manner as a homogeneous group oflaboratory animals.Dr. Bryan was also critical of Dr. Scribner’s assumptions that thecarcinogenic potential of MOCA in humans could be equated to that ofbenzidine. Dr. Bryan noted that humans are typically exposed to avariety of substances while laboratory tests on animals attempt toisolate the effect only one chemical produces in the animal. Hepostulated that the workers who had contracted bladder cancer afterexposure to benzidine had also been exposed to a number of otherchemicals and that the high incidence of bladder cancer should beattributed to the mixture of exposures and not solely to benzidineexposure. Furthermore, if MOCA was as potent a carcinogen as benzidine,Dr. Bryan was of the opinion that human cases of bladder cancer wouldalready have begun to appear among MOCA workers. The absence of any suchcancers, as shown by the study of du Pont workers in which no adversehealth effects attributable to MOCA were found, indicated that Dr.Scribner had overestimated the risk of bladder cancer in humans from MOCA.Dr. Bryan’s reasons for believing that extrapolations from animalexperiments to estimate human risks were not valid within a reasonabledegree of scientific certainty largely correspond to the reasonsexpressed by the Secretary for rejecting quantitative risk assessment ina rulemaking directed at developing a general policy for regulatingcarcinogens. That policy, which the Secretary issued on January 22,1980, examined the considerations relevant to the regulation ofcarcinogens. \”Identification, Classification and Regulation of PotentialOccupational Carcinogens,\” 45 Fed. Reg. 5002 (1980). One of theprincipal issues considered in the rulemaking was whether a substance’scarcinogenic potency should be considered in establishing a permissibleexposure level, i.e., whether quantitative risk assessment couldreliably estimate the risk presented to workers by a carcinogen. Afterreceiving numerous expert opinions on both sides of the question, theSecretary rejected such an approach, saying:Extrapolation from animal data to predict risks in humans introducesmany additional uncertainties. These include selection of appropriatescaling factors for size, lifespan, and metabolic rate; differences inroutes of exposure, duration and schedule of exposure, absorption,metabolism, and pharmacokinetics; differences in intrinsicsusceptibility and repair capabilities; intra-population variation insusceptibility; and exposure to other carcinogens and intrinsic andextrinsic modifying factors. At least theoretically, these factors canaffect the relative response of humans and animals by many orders ofmagnitude.[[13]]Id. at 5200. Thus, the Secretary has concluded that quantitativeextrapolations from animal data are too speculative to provide usefulestimations of human risk.The number of assumptions made by Dr. Scribner to extrapolate human riskfrom the animal studies on which he relied renders Dr. Scribner’sconclusions too speculative for purposes of section 5(a)(1). Moreover,some of the studies relied upon in making the quantitative riskassessment involved exposure to benzidine rather than MOCA. Dr. Bryan’stestimony demonstrates that conclusions as to the carcinogenicity of onechemical cannot readily be drawn from experience with a differentchemical. Dr. Scribner’s risk assessment was based on the assumptionthat the exposed workers would excrete 50 micrograms of MOCA a day for250 days per year. However, this assumption is based on the urine testsof only a few Conap employees on a single day. As to Kastalon, therecord is silent on the amount of MOCA in the employees’ urine. We aretherefore unable to correlate Dr. Scribner’s risk assessment to thelevels of MOCA to which the workers were exposed. Nor did Dr. Scribnertake into consideration the information obtained from the du Pont studywhich showed no increase in the incidence of bladder cancer to du Pontworkers exposed to MOCA. We therefore conclude that the quantitativerisk assessment presented by the Secretary is too speculative toestablish that Kastalon’s and Conap’s employees were exposed to asignificant risk of harm within the meaning of section 5(a)(1) of theAct. Accordingly, we vacate the citations issued to Kastalon and Conapalleging violations of the general duty clause.Because we conclude that the Secretary failed to prove that Kastalon’sand Conap’s employees were exposed to a hazard, we need not and do notdecide whether the Secretary proved the remaining elements of a generalduty clause violation.VWe now turn to the Secretary’s allegations that Conap violated standardsgoverning the provision and use of personal protective equipment.As noted above, the primary means by which MOCA can enter the body isthrough skin absorption. MOCA is only present as an air contaminant ifhandling of the chemical generates airborne dust. In the personalprotective equipment citations issued to Conap, the Secretary allegesthat the company did not provide and\/or require employees to useequipment that would minimize skin contact and inhalation of MOCA. Thestandards cited by the Secretary, 29 C.F.R. ?? 1910.132(a) and1910.134(a)(2), provide as follows:? 1910.132 General requirements.(a) Application. Protective equipment, including personal protectiveequipment for eyes, face, head, and extremities, protective clothing,respiratory devices, and protective shields and barriers, shall beprovided, used, and maintained in a sanitary and reliable conditionwherever it is necessary by reason of hazards of processes orenvironment, chemical hazards, radiological hazards, or mechanicalirritants encountered in a manner capable of causing injury orimpairment in the function of any part of the body through absorption,inhalation or physical contact.? 1910.134 Respiratory protection.(a) Permissible practice.* * *(2) Respirators shall be provided by the employer when such equipment isnecessary to protect the health of the employee. The employer shallprovide the respirators which are applicable and suitable for thepurpose intended. The employer shall be responsible for theestablishment and maintenance of a respiratory protective program whichshall include the requirements outlined in paragraph (b) of this section.The Secretary alleges that Conap violated these standards becauseemployees in various areas of the plant were not using imperviousgloves, impervious suits, shoe covers, goggles, head coverings, andappropriate respirators. One of the citation items also alleges thatConap violated section 1910.132(a) because MOCA was present on surfacesof a piece of equipment. In the Secretary’s view, that means theequipment was not maintained in a sanitary or reliable condition, as thestandard requires.We vacate these citation items for the same reason we vacate the generalduty clause citations: the Secretary failed to prove that Conap’semployees were exposed to a hazard. Section 1910.132(a) requires thatpersonal protective equipment be provided and used \”wherever it isnecessary by reason of hazards of processes or environment,\” and section1910.134(a)(2) mandates that employers provide respirators \”when suchequipment is necessary to protect the health of the employee.\” Thus,like the general duty clause, the Secretary must show that a significantrisk to employees is present as a necessary element of proof that anemployer violated either standard. See Donovan v. General Motors Corp.,764 F.2d 32 (1st Cir. 1985) (significant risk test for proof of a hazardapplies under section 1910.132(a)); Modern Drop Forge Co. v. Secretaryof Labor, 683 F.2d 1105, 1114-15 (7th Cir. 1982) (significant risk testapplies where standard does not presume existence of a hazard); AnoplateCorp., 12 BNA OSHC at 1681, 1986 CCH OSHD at p. 35,680 (where standardrequires proof of a hazard, Secretary must show a significant risk toemployees exists). As the Secretary failed to prove that MOCA presenteda significant risk to employees at the exposure levels present inConap’s plant, it follows that he failed to prove that Conap violatedthe personal protective equipment and respirator standards.Although we vacate these items due to lack of proof of a hazard, we alsonote that there are other deficiencies in the Secretary’s evidence as tocertain items. In item 8 of the citation, the Secretary alleged that oneemployee wore an unapproved respirator and another wore no respirator atall. However, none of the measurements made by the Secretary showed anydetectable levels of airborne MOCA, so even assuming that exposure tosome amount of MOCA is hazardous, the Secretary failed to prove the needfor respirators.[[14]]Conap also provided various items of protective equipment to minimizeskin contact with MOCA, including polyethylene gloves, full-bodyimpervious paper uniforms, and paper hats. Use of this equipment wasleft to the discretion of employees. The Secretary alleged in items7(b), (d), and (e) of the citation that Conap violated section1910.132(a) by not requiring that the equipment be used in various areasof the plant. The Secretary also alleged in items 7(a) and (c) thatConap violated section 1910.132(a) because employees were not usinggoggles or other eye protection and were not wearing shoe covers toprevent spilled MOCA from being tracked throughout the plant.Some of these allegations involve employees who were not exposed toMOCA. For example, in subitems 7(b)(3), (c)(2), and (e)(2), theSecretary alleged that employees in the room containing the AutomaticProcess Control machines (\”the APC room\”) were not wearing imperviousgloves, shoe covers, and impervious clothing. However, employees did nothandle MOCA in the APC room. The MOCA was mixed with the prepolymer inthe APC machine before the mixture was discharged from the machines.Employees could contact the mixture after it came out of the machines,but there is no evidence that this would be harmful. To the contrary,Robert Turkington, an industrial hygienist who testified for theSecretary, stated that employees could not absorb MOCA by contacting themixture of MOCA and prepolymer. Thus, the Secretary failed to show thatthere was any possibility of employee absorption of MOCA in the APC room.The Secretary also alleged in item 7(b)(1) a violation of section1910.132(a) because employees in the belts room did not wear gloves allthe time. Employees weighed and melted MOCA in the belt room, but theyalso performed other operations there.[[15]] Although the record showsthat employees in the room did not wear gloves all the time, that doesnot prove that employees failed to wear gloves when they handled MOCA.The Secretary alleged in item 7(a) that employees did not wear eyeprotection in two areas where MOCA was handled. However, there is noevidence that MOCA presented any special danger to the eye. Theprecautions recommended by du Pont, on which the Secretary places somuch emphasis, do not mention the need for eye protection. Thus, theSecretary failed to show any hazard necessitating eye protection.The Secretary alleged in item 7(c) that Conap violated section1910.132(a) because employees did not wear shoe covers in the plantareas where MOCA was used. According to the Secretary, employees shouldhave worn shoe covers in rooms where MOCA was used and should havediscarded them before leaving the room, thus preventing MOCA from beingtracked into areas of the plant where MOCA was not used. The Secretarydid not show, however, that such a practice would significantly reduceemployee exposure to MOCA. There is no evidence that MOCA was in factbeing tracked throughout Conap’s plant. Also, we assume that allemployees wore shoes, so even if MOCA was present on the floors, therewould appear to be little, if any chance, it could be absorbed throughthe skin of employees. Even under the Secretary’s argument that anymeasurable exposure to MOCA presents a hazard, the Secretary failed toprove the need for shoe covers.The Secretary alleged in item 6 that Conap failed to maintain a glovebox in a sanitary and reliable condition. As described earlier, theglove box is one of the devices Conap used to minimize employee contactwith MOCA. It is an enclosed chamber into which a closed container ofMOCA is placed and manipulated through rubber gloves installed on theside of the chamber. Wipe samples taken during the inspection of Conap’splant revealed 3.6 micrograms of MOCA inside one glove, 9.9 microgramsinside the other. and 460 micrograms on top of the glove box. TheSecretary argues that these measurements show that the glove box was notmaintained in a sanitary condition. We do not agree. The drums of MOCAused by Conap each contained 132 pounds of the chemical. Translated intomicrograms, each drum contained approximately 60 billionmicrograms.[[16]] To find a violation based on the presence of a fewmicrograms, or even a few hundred micrograms, would impose on employersthe duty to eliminate all traces of a chemical from all surfacesemployees may contact. Such a requirement is simply unrealistic. Thepurpose of the glove box was to minimize employee contact with MOCA, andthe fact it did not eliminate such contact entirely does not show it wasnot maintained in a sanitary condition.VIThe evidence in these cases strongly suggests that MOCA is a humancarcinogen. Certainly it would be preferable not to be exposed to acarcinogen than to be exposed to even a small amount. However, manysubstances to which people are exposed daily are known carcinogens, andthe Benzene Case recognizes that human activity cannot be guided by thesole objective of totally removing exposure to carcinogens. Instead, areasoned judgment must be made as to whether the amounts to which peopleare exposed present a significant risk of harm. In these cases, theSecretary alleges that Kastalon and Conap violated the general dutyclause and certain general standards because their employees wereexposed to MOCA. The Secretary has not, however, proven by apreponderance of the evidence of record that the amounts of MOCA towhich Kastalon’s and Conap’s employees were exposed were hazardous. Weare therefore compelled to conclude that the Secretary has failed tosustain his burden of proof and to vacate the citations.From a broader perspective, to find violations here would be beyond thelimited adjudicatory role of the Commission. We would effectively beestablishing a permissible exposure limit through the adjudicatoryprocess without regulated industries having the opportunity for inputunder the Act’s notice and comment rulemaking procedures. While this maybe appropriate where appropriate exposure limits have been firmly andscientifically established, see, e.g., American Smelting and RefiningCo. v. OSHRC, 501 F.2d 504 (8th Cir. 1974), it is not desirable where itrequires \”findings . . . on the frontiers of scientific knowledge.\”Benzene Case, 448 U.S. at 656. Such findings are uniquely suited torulemaking, in which the Secretary can \”make a policy judgment as towhether a specific risk of health impairment is significant in terms ofthe policy objectives of the statute.\” Id. at 663 (Burger, C.J.,concurring). Moreover, in a rulemaking proceeding, all interestedpersons have the opportunity to be heard, and a rule gives employersnotice of what they must do to provide safe and healthful workplaces. Ifthe Secretary believes that MOCA presents a significant risk in theworkplace, he retains the authority under section 6(b) of the Act tocomplete the rulemaking he has already started.Finally, we note that Kastalon contends that the costs it would incur ifthe Secretary’s abatement order is enforced would render ituncompetitive within its industry and thus put it out of business.Although it is not necessary to reach the merits of this contention, wemention it here because it reinforces the importance of proceedingthrough rulemaking instead of the general duty clause where a decisioncan be expected to have broad impact within an industry or industries.As the Court of Appeals for the District of Columbia observed:[I]f adoption of the precaution would clearly threaten the economicviability of the employer, the Secretary should propose the precautionby way of promulgated regulations, subject to advance industry comment,rather than through adventurous enforcement of the general duty clause.National Realty & Construction Co. v. OSHRC, 489 F.2d 1257, 1266 n.37(D.C. Cir. 1973).The judges’ decisions are affirmed and the citations are vacated. FORTHE COMMISSION Executive SecretaryDATED: JUL 23 1985————————————————————————The Administrative Law Judge decision in this matter is unavailable inthis format. To obtain a copy of this document, please request one fromour Public Information Office by e-mail ( [email protected] ), telephone (202-606-5398), fax(202-606-5050), or TTY (202-606-5386). FOOTNOTES:[[1]] \”MOCA\” is a registered trade name of E.I. du Pont de Nemours &Co., Inc., which at one time was the chemical’s primary manufacturer. DuPont no longer manufactures MOCA.[[2]] Section 5(a)(1), 29 U.S.C. ? 654(a)(1), provides:Each employer shall furnish to each of his employees employment and aplace of employment which are free from recognized hazards that arecausing or are likely to cause death or serious physical harm to hisemployees.[[3]] Section 6(b) of the Act, 29 U.S.C. ? 655(b), provides that theSecretary may promulgate occupational safety and health standardsfollowing rulemaking proceedings in which interested persons are givennotice of the proposed rule and an opportunity to be heard. Thesenotice-and-comment rulemaking provisions are similar to those in 5U.S.C. ? 553, section 4 of the Administrative Procedure Act, 5 U.S.C. ?551 et seq. (\”the APA\”), but impose additional requirements not found inthe APA. Among those additional requirements are provisions governingthe use of advisory committees. The Secretary may convene such acommittee to advise him regarding a standard under consideration. Wherehe does so, he must publish a proposed standard within 60 days ofreceiving the committee’s recommendations. Interested persons are given30 days to submit comments and request a hearing. In the case of theMOCA standard, the Secretary published the proposed standard beforereceiving the advisory committee’s recommendations, and he held ahearing on the standard less than 30 days after receiving therecommendations. The court held that this procedure did not conform tothe statutory requirements because it did not give interested persons anadequate opportunity to review the committee’s recommendations beforesubmitting comments on the standard and participating in the hearing.[[4]] The record indicates that two companies in addition to Kastalonand Conap were cited. A 1976 citation issued to Roadway Tire & RubberCompany was resolved in a settlement agreement. A citation issued in1979 to Nazar Rubber Company was vacated by an administrative law judge,and the Secretary did not seek review of that decision. Nazar RubberCo., 81 OSAHRC 52\/D13, 9 BNA OSHC 1960, 1981 CCH OSHC ? 25,437 (No.79-4005, 1981).[[5]] This was particularly true in Kastalon, where the abatementrequirements listed by the Secretary were largely taken verbatim fromthe invalidated MOCA standard.[[6]] The Secretary adopted this standard under section 6(a) of the Act,29 U.S.C. ? 655(a), which required him to summarily promulgate nationalconsensus standards and established federal standards as occupationalsafety and health standards within two years of the Act’s effective datewithout notice-and-comment rulemaking proceedings. The OSHA standard wasoriginally adopted as a standard by the American National StandardsInstitute in 1969.[[7]] We note that the United States Court of Appeals for the FifthCircuit has held that the significant risk test should not be applied inenforcing the general duty clause. Kelly Springfield Tire Co. v.Donovan, 729 F.2d 317, 323-24 (5th Cir. 1984). We respectfully disagreewith that court’s conclusion. The Fifth Circuit reasoned that theBenzene Case dealt with the promulgation of standards and was thereforeof limited relevance in the different context of the general dutyclause. We believe, however, that the Supreme Court’s conclusion thatthe Act was not intended to create risk-free workplaces applies equallyto the enforcement of the general duty clause as to the promulgation ofstandards. As we have stated, Congress did not intend for the generalduty clause to provide broader protection than could be achieved throughthe promulgation of standards. Thus, a limitation on the Secretary’sauthority to issue standards necessarily also limits the scope of thegeneral duty clause.[[8]] The only record evidence regarding a specific study of humanexposure to MOCA involves a study by du Pont. Du Pont began developmentwork with MOCA in 1954 and commenced full-scale commercial production in1962. Between 1967 and 1971, Du Pont studied the medical records of allits employees who had been involved with MOCA and found no adversehealth effects attributable to MOCA.[[9]] In the du Pont study, six dogs were fed MOCA in their daily diet.One died early in the experiment from unrelated causes, and theremaining five all ultimately contracted cancer. None of the six dogs inthe control group contracted cancer, indicating that MOCA had inducedthe cancers in the exposed group. See note 12 infra.[[10]] The Secretary cites National Realty & Construction Co. v. OSHRC,489 F.2d 1257, 1265 n. 32 (D.C. Cir. 1973), for the proposition that ahazard is recognized within the meaning of the general duty clause if\”safety experts who are familiar with the circumstances of the industryor activity in question\” would have recognized the existence of ahazard. The court made this statement in the context of holding that thegeneral duty imposed on employers by section 5(a)(1) was an achievableone, and that the test for recognition of the hazard was therefore anobjective one. The court stated, in full, \”The standard would be thecommon knowledge of safety experts who are familiar with thecircumstances of the industry or activity in question.\” Id.In this case, it is very doubtful whether Dr. Bryan’s opinions can besaid to represent the \”common knowledge\” of the polyurethane industry.Dr. Bryan did not work in the industry, but was retained by thePolyurethane Manufacturers Association to provide it with expertise theindustry did not possess. In general, we think it would be unrealisticto hold an industry to the standard of knowledge of an outside expert itengages to provide it with specialized expertise. However, because weconclude that the evidence does not establish the existence of a hazard,we need not decide whether Dr. Bryan’s recognition of a hazard would besufficient to find that the polyurethane industry recognized the hazard.[[11]] We also note that the general knowledge that a chemical is asuspect human carcinogen and should be controlled does not equate withrecognition that exposure to any amount of the chemical is hazardouswithin the meaning of the general duty clause. We, therefore, do notagree with the Secretary that the polyurethane manufacturing industryrecognized the existence of a hazard at any detectable level of MOCA.Additionally, we note that Kastalon and Conap took considerable steps toreduce the exposure of their employees to MOCA. No employees had beenknown to suffer ill effects from working with MOCA. There is no evidencethat Kastalon and Conap believed the measures they took were inadequateor that they recognized that a hazard existed at their worksites.[[12]] In a typical animal experiment, a certain number of laboratoryanimals are exposed to a measured quantity of a chemical while a controlgroup of similar animals is maintained in a similar fashion but is notexposed to the chemical. If a larger number of exposed animals thancontrol animals contract a disease and the disparity is statisticallysignificant, it can be concluded that the chemical causes the disease.The statistical probability that an animal will contract the disease atthe exposure level used in the experiment can also be calculated. If theexperiment is conducted with different groups of animals exposed atseveral different levels, the degree to which the probability ofcontracting the disease varies with the exposure level — the\”dose-response curve\” — can be obtained. In order to extrapolate thisquantitative animal data to determine the risk the chemical presents tohumans, a number of assumptions must be made. First some assumption mustbe made about the relative sensitivity to the chemical exhibited byhumans and the experimental animals. Assumptions must also be made aboutdifferences in conditions under which humans and laboratory animals areexposed. For example, the experiment may involve animal ingestion of thesubstance, but human exposure may typically be through inhalation. Insuch a situation, an assumption must be made about the relative riskposed by the different exposure routes. Also, animal experiments ofteninvolve exposure levels that are much higher than humans typicallyencounter in the workplace. In order to estimate the risk to humans fromthe data gathered in such experiments, assumptions must be made aboutthe relative risk at high and low dosages. One possible assumption, forexample, is that the risk is directly proportional to the dosage–intechnical terms, that the \”dose-response curve\” is a straight line.Experience shows, however, that it is extremely difficult to predict therisk to humans at low dosages from the results of information gatheredat high dosages, for substances that are toxic at high dosages are oftenrelatively less harmful or even completely safe at the typical dosagesworkers receive.[[13]] The Secretary noted that estimates of the probability that humanscould develop cancer from saccharin ingestion calculated by differentscientists assuming different models for cancer induction varied byseven orders of magnitude, i.e., by a factor of ten million. (One orderof magnitude represents a tenfold difference in the estimated risk; twoorders of magnitude represents a hundredfold difference). 45 Fed. Reg.at 5196-5200.[[14]] The Secretary also alleged in item 9 that Conap did not establishand maintain a respiratory protection program because it did not trainemployees in the use of respirators and did not have written respiratorinstructions. However, absent evidence of a hazard requiring the use ofrespirators, an employer cannot be found in violation for failing toimplement a respirator program. Gulf Oil Corp., 83 OSAHRC 21\/A2, 11 BNAOSHC 1476, 1480, 1983 CCH OSHD ? 26,529, p. 33,819 (No. 76-5014, 1983).[[15]] Much of the Secretary’s evidence pertaining to the belt room wasdirected at an operation in which the liquid mixture of MOCA andprepolymer was poured over a mandrel on a lathe to form polyurethanebelts. The evidence establishes that this was a \”very sloppy\” processand resulted in considerable spillage. However, as noted above, theevidence shows that there was no hazard of MOCA contact once the MOCAwas mixed with the prepolymer. Thus, the evidence of the sloppiness ofthe belt-forming operation is irrelevant to whether there was a hazardof MOCA exposure in the belt room.[[16]] One pound equals 454 grams. Each gram contains one millionmicrograms. Thus, the number of micrograms in a drum is 132 multipliedby 454 multiplied by one million.”