” face=\”Arial\”>GLASS, MOLDERS, PLASTIC,POTTERY AND ALLIED WORKERS, LOCAL 208.Authorized Employee Representative.OSHRC Docket No. 88-0348DECISIONBefore: FOULKE, Chairman: WISEMAN and MONTOYA, Commissioners. BY THE COMMISSION:Industrial Glass, a subsidiary of Tropicana Products, Inc.,manufactures glass bottles at its workplace in Bradenton, Florida. In its manufacturingprocess, Industrial Glass melts sand and other ingredients at a temperature ofapproximately 2100 Fahrenheit, feeds the molten glass into molds, and then empties themolds onto a conveyor which carries them through stations where the bottles are inspectedand tempered. The Industrial Glass employees who operate and maintain the equipment usedto manufacture glass bottles in the forming department must work very near the tankscontaining the molten glass and the hot bottles on the conveyors, all of which radiate alarge amount of heat. The Secretary of Labor, acting through the Occupational Safety andHealth Administration (\”OSHA\”), issued a citation alleging that Industrial Glasshad violated section 5(a)(1) of the Occupational Safety and Health Act of 1970 (\”theAct\”), 29 U.S.C. ? 654(a)(1).[[1]] because these employees were required to work inexcessively high temperatures, exposing them to the hazard of heat stress and to otherheat-related conditions.Industrial Glass contested the citation, and a hearing was heldbefore former Commission Administrative Law Judge Joe D. Sparks. The judge found that,although it was clear that temperatures near the machines were very hot and that workingthere was uncomfortable, the Secretary had failed to prove that the working conditionsconstituted a hazard. The judge therefore vacated the citation. The judge’s decision wasdirected for review pursuant to section 12(j) of the Act, 29 U.S.C. ? 661(j). Havingfully reviewed the record in this case, we find that the judge did not err in vacating thecitation. We therefore affirm his decision.I. THE INDUSTRIAL GLASS OPERATIONThere are three bottle-making plants at the Industrial Glassfacility in Bradenton. Plants I and 2 are housed in the same structure. while Plant 3 isin another building. In each of the three plants there are four bottle-making machines or\”shops.\” Each of the machines, called \”independent section machines,\”is approximately eight feet high and twelve feet wide. There are eight-section machines,which produce 16 bottles at a time, and ten-section machines, which make 20 bottles at atime. A platform four feet deep runs across the front of the machines for the employees tostand on while they are working near the machines and the conveyor belts.The ingredients that go into the glass are melted in anoverhead tank at a temperature of approximately 2100 F. The molten glass is then led bygravity to each of the machines, where \”gobs\” of molten glass are fed into themolds. The machine puts two gobs into each mold to form a \”parason\” (a gob withan air bubble in the center). At this stage, the molten glass has cooled to approximately1200 F. Compressed air is fed into the mold to distribute the glass evenly inside the moldto form the bottle. Then the mold opens and the formed bottle is pushed onto a conveyor,which carries it through an inspection light, where the operator checks for defects. Thebottles come out of the molds onto the conveyor at a temperature of approximately 900 F.By the time the bottles reach the inspection light, the temperature has dropped to about725 F. From the inspection light, the conveyor carries the bottles to an oven called a\”lehr,\”where the bottles are \”annealed\” (alternately heated and cooledslowly to temper them). When the bottles enter the lehr, their temperature is about 600 F.The plants Operate twenty-four hours a day, seven days a week.With some exceptions, the employees involved in glassmaking work one shift for seven days,rotate to the next shift for seven days, work the third shift for seven days, and thenhave a week off. They therefore work twenty-one straight days. Seven hourly employees areassigned to each plant: four machine operators, one for each machine; two upkeepmechanics, each of whom is responsible for two machines; and one floor attendant, whoseduties are to clean up throughout the plant and to assist the operators and upkeepmechanics. There is also one supervisor, who may spend approximately a third to half ofhis time on the floor of the plant, but who is generally not involved in the physicaloperation and maintenance of the machines.The average tenure of the non-supervisory employees inIndustrial Glass’s forming department, which is also known as the \”hot end,\” isover ten years. When a vacancy does occur, the company sometimes hires a journeymanmachine operator who has experience working in another glass factory; but, more often, thecompany promotes from within. Employees who have worked in the \”cold end\” orpackaging department of the plant may bid for the job based on seniority. An employeeentering the forming department starts as a floor attendant, the job that takes the leasttraining and has least exposure to the intense heat near the machines. The floor attendantassists the operators and learns how to operate the machines on his own. After learningthis job, the floor attendant may be promoted to apprentice operator, then to journeymanoperator, and finally to upkeep mechanic.The operators’ duties include keeping the machines runningsmoothly, swabbing the molds with an oil-and-graphite lubricant to keep the bottles fromsticking to the molds, inspecting the bottles as they go through the inspection light,taking a number of the bottles off the conveyor for additional testing, and helping theupkeep mechanic when he is working on the machine. The employees’ activities varysubstantially from day to day and from machine to machine. Each employee receives a 15-minute break in the morning, a 20-minute lunch break, and a 15-minute break in theafternoon (or at corresponding times during other shifts). If there is a jam or a majorbreakdown, an employee may have to spend extended amounts of time at the hot machines andmay have to work through his break, although there is some dispute about how often thisoccurs.While the entire plant is hot, the heat varies from area toarea. The hottest area is near the machines because that is where the molten glass andnewly-made bottles are radiating the heat. Employees can, however, obtain relief from theintense heat nearest the machines. For example, the operator will frequently stand backseveral feet observing the entire machine operating and watching for malfunctions, apractice called \”troubleshooting.\” An operator who begins to feel that he isbeing affected by the heat can get the floor attendant or the upkeep mechanic to relievehim. There are large fans, five or six feet in height and width, throughout the plants,with at least one and sometimes two fans per-machine. In addition, there are waterfountains located nearby, and there are drinks available from vending machines in the air-conditioned break room.II. THE INSPECTION AND THE CITATIONOn August 26 and September 1, 1987, an OSHA industrialhygienist (\”the IH\”) inspected plants 1 and 2. During his initial visit, the IHtook readings at several different locations in the general area where the employeesworked to determine the Wet Bulb Globe Temperature (\”WBGT\”), which combines airtemperature, humidity, and air movement (which affects cooling by evaporation). It isconsidered a better indicator of the effects of heat on individuals than just the ambientair temperature, which can be measured by a household thermometer, known as a dry bulbthermometer [[2]]. The WBGT readings ranged from 83.4 to 101.2 F. The IH also took drybulb readings, which ranged from 91 to 115 F.The IH made his second visit to Industrial Glass in the lateafternoon because he had been told during his first visit that it was the hottest time ofday. He stayed about an hour and a half, during which time he took WBGT readings in thevicinity of three different machines. Again, his readings ranged from 83.4 to 101.2 F.During the two visits, he observed the employees’ activities and subsequently calculatedan estimate of how much energy was required to perform their duties.Heat stress is caused by a combination of environmental heatand metabolic heat. Environmental heat includes the air temperature, the humidity, the airflow, and the radiant heat emanating from any hot surfaces. Metabolic heat, the heatproduced within the body, is increased by physical activity. Because the IH believed afterthe inspection that some of the employees were exposed to a combination of metabolic andenvironmental heat that exceeded the threshold limit values (\”TLVs\”) recommendedby the American Conference of Governmental Industrial Hygienists (\”ACGIH\”), theSecretary issued a citation alleging a violation of section 5(a)(1) of the Act. Thecitation alleged:(a) Employees in the \”hot end\” of the glass plantwere exposed to the hazard of excessive heat stress during the performance of their dutiesoperating and maintaining the equipment used to manufacture glass bottles. Typically,during the operation of the equipment the worker rotates between his desk, the front endof the equipment and the back side of the equipment. (b) The Wet Bulb Globe Temperature Index (WBGT-IN) recorded during a survey on September1, 1987 from a low of 26.5 degrees Centigrade to a high of 38.4 degrees Centigrade. Suchexposures may lead to the development of serious heat induced illnesses such as: heatstroke, heat exhaustion, cramps and behavioral disorders, as correlated to guidelinesestablished by the American Conference of Governmental Industrial Hygienists and theNational Institute for Occupational Safety and Health.(c) Among other methods, one feasible and acceptable abatementmethod to correct this hazard is to provide shielding or barriers that areradiant-reflecting or heat-absorbing, between the heat source and the worker.(d) Another method would be to limit exposure time byimplementing a work-rest regimen which requires mandatory, regularly scheduled breaks foremployees in the \”hot end.\”(e) A water supplementation schedule presented in such a wayemployees are stimulated to drink five to seven ounces of liquid every fifteen to twentyminutes will serve to augment any control measures used.(f) Other considerations include physical fitness andacclimatization of employees, as well as the type of clothing worn when working in hotenvironmental conditions.(g) Training of employees in the recognition and treatment ofheat related illness and the effects of non-occupational factors such as: drugs, alcohol,and physical fitness is also recommended.Ill. THE SECRETARY’S BURDEN OF PROOFIn order to prove it violation of section 5(a)(1), theSecretary must establish that: (1) there was an activity or condition in the employer’sworkplace that constituted a hazard to employees: (2) either the cited employer or theemployer’s industry recognized that the activity or condition was hazardous; (3) thehazard was causing or likely to cause death or serious physical harm: and (4) there was afeasible means to eliminate the hazard or materially reduce it. Coleco Indus. Inc., 14 BNAOSHC 1961, 1963, 1991 CCH OSHD ? 29,200 p. 39.070(No. 84-546. 1991).IV. EVIDENCE AS TO THE EXISTENCE OF A HAZARDMuch of the hearing was devoted to expert testimony. Inaddition to the testimony of the IH, the Secretary presented Dr. Wilbur Spaul, aconsultant who holds a Ph.D. degree in public health and is a specialist in industrialhygiene, concentrating in heat stress. The company presented two expert witnesses of itsown. The three outside experts and the IH all agreed that heat stress is a combination ofenvironmental or ambient heat conditions (the heat in the air, the humidity, and the airvelocity) and the internal or metabolic heat Produced by the activity being performed(\”the workload\”), less the cooling effects of evaporation.A. THE SECRETARY’S EXPERT TESTIMONYIn addition to taking temperature measurements, the IH hadestimated the metabolic heat generated by the employees in performing their duties. To dothis, he observed the employees performing their jobs and estimated their energyexpenditure using tables in a booklet entitled Threshold Limit Values and BiologicalExposure Indices published by the ACGIH. The IH stated that he considered the work to belight to moderate and estimated the metabolic workload to he about 396 kilocalories(\”Kcals\”) per hour, which exceeded the limits for exposure to combinedenvironmental and metabolic heat contained in the ACGIH booklet. Although the IH statedthat he relied on his professional judgment and his previous experience in making thiskind of assessment, he admitted that he had no actual training in workload assessment andthat he had performed such an evaluation only once before, in a case that had not beenlitigated. After acknowledging that the employees had given him widely varying estimatesof the amounts of time spent performing various chores, he admitted that the figure hearrived at was simply his estimate of the energy being burned and that it may not be anaccurate reflection of the actual workload.The consultant retained by the Secretary, Dr. Spaul, testifiedthat he went to Industrial Glass’ plant and performed \”a very brief fieldevaluation,\” spending approximately an hour and a half in the forming department,during which time he took temperature readings of his own. His observations indicated thatthe operators divided their time approximately equally at the operator’s station, theoperator’s work bench, and at the machine, where they check, adjust, and swab the machine.Using a psychrometer to determine the WBGT, he took readings at these three locationsaround machine number 8, plus readings in front of the fan in that area. He also tookreadings at the same locations around machine number 7, as well as readings in the breakroom and in the shade outside the building. His measurements near the machines had aparticularly high globe reading, which indicates that there is a high radiant heat loademanating from the machines and the bottles.At the hearing, the expert presented an exhibit which displayedhis temperature measurements at these locations. That exhibit shows the air temperaturemeasured by a dry bulb, the air temperature measured by a wet bulb, the temperaturemeasured by the globe, air velocity, and the WBGT reading, which is calculated by addingseven tenths of the wet bulb reading to three tenths of the globe reading. His WBGTreadings ranged between 73.3 F in the break room to 104.4 F at the operator’s station nextto machine number 7. He stated, however, that there are many indexes that can be used todetermine the likelihood that heat stress will occur, and that he does not use WBGTreadings when he is retained by a company to evaluate the feasibility of engineeringcontrols in its plant because there are better indicators.As part of his analysis, Dr. Spaul also estimated the energybeing expended by the employees to do the work. Using the operations performed at thelocations where he took temperature readings. he calculated a time-weighted average of theenvironmental heat load and a one-hour time-weighted average of the metabolic workload.First he estimated the work-rest schedule of the operators, based on his observations ofthe employees’ activities during his visit to the plant and his subsequent telephoneconversations with the Industrial Glass safety director. He estimated that, in a typicalhour, the operators would spend twenty minutes at the work bench, twenty minutes at theoperator’s station, and twenty minutes at the machine. Relying on these estimates of thetime spent on each task, he created a 20-20-20 model and calculated the one-hourtime-weighted average WBGT readings for the areas around machine number 7 and machinenumber 8, using the WBGT temperatures he had taken around both machines. Based on hisestimate of the work activity, he calculated that the time-weighted average WBGT readingwas 98.1 F around machine number 7 and 95.4 F around machine number 8.After he had spoken to the Industrial Glass employees, Dr.Spaul checked with the safety managers of other glass manufacturing plants to confirm thatthe employees’ estimates of the time spent doing each task sounded reasonable. Based onthese conversations, he calculated three other one-hour time-weighted WBGT exposures formachine number 8, using different estimates of how long the operator spent at each of thethree locations measured. Two of these calculations included a provision for time spent bythe operator near the fan. In each of his four sets of calculations, the time estimatesare in multiples of five minutes.Using the three locations he had used in his calculations ofWBGT exposure, Dr. Spaul evaluated the tasks performed at each of the positions andestimated the workload for each task, performing two sets of calculations to account forthe different estimates of the time spent at each location doing the tasks performedthere. He also did two sets of workload calculations that allowed for time spent near thefan. His calculations produced a range of energy burned between 190.5 and 312.5 Kcals perhour. When he completed these calculations, Dr, Spaul had four one-hour time-weightedaverages for metabolic and environmental heat, as shown in the table below: Operator’s Work Bench Machine Fan WBGT Kcall\/hr Station (F) 20 min (98.4) 20 min (92.4) 20 min (95.5) 95.4 210 – 290 15 min (98-4) 20 min (92.4) 25 min (95.5) — 95.2 212.5 – 312.5 15 min (98-4) 20 min (92.4) 20 min (95.5) 5 min (86.3) 94.4 201.5 – 242.5 15 min (98.4) 20 min (92.4) 15 min (95.5) 10 min (86.3) 93.7 190.5 – 250.5 Dr. Spaul then compared his environmental and metabolic heatquantities with those in the graph in the ACGIH booklet and determined that all hiscombined environmental and metabolic heat figures that he arrived at exceeded the limitson the ACGIH graph. He therefore concluded that the conditions at Industrial Glass exposedthe operators to the hazard of heat stress. Dr. Spaul testified that Occupational Exposureto Hot Environments, Revised Criteria for a Recommended Standard, 1986 edition, publishedby the National Institute of Occupational Safety and Health of the Department of Healthand Human Services (\”NIOSH\”), and the Engineering Field Reference Manualpublished by the American Industrial Hygiene Association (\”AIHA\”) alsoindicated, based on his figures, that the operators were exposed to the hazard of heatstress.On cross-examination by the company. Dr. Spaul agreed thatthere is a considerable amount of variation in the temperatures throughout the formingdepartment.\u00a0 Dr. Spaul testified that he did observe employees working at a number oflocations where he did not take temperature readings, including the water fountain, theweighing scale, and the catwalk behind the machine. As a result, he could not say whatlevels of hear the employees were exposed to at those locations. Dr. Spaul stated that the company must have known that itsemployees were exposed to a hazard because the employees complained to management aboutthe heat and because the company had provided certain controls to limit heat exposure,such as insulation on the furnaces and melting tanks, large fans, water fountains nearby,and electrolyte drinks available in the vending machine in the air-conditioned break room.In addition, electrolyte replacements tablets and drinks were available from the nursingstaff. Dr. Spaul expressed the view, however, that these efforts were inadequate.B. TESTIMONY BY THE COMPANY’S EXPERTSThe company presented two experts, Dr. Bertram Dinman and Dr.Stephen Horvath, both of whom were consultants on the panel that reviewed the NIOSHrecommended standard and were contributors to Patty’s Industrial Hygiene and Toxicology, awidely-used treatise in the field. Dr. Dinman is a physician who also holds a doctorate inoccupational medicine and has been a professor in the fields of public health,occupational medicine, and industrial hygiene. He was an advisor to the military onenvironmental hygiene, including heat stress, and for several years was medical director,then vice president for health and safety of Alcoa, which has many employees exposed tohigh temperatures in its aluminum smelting operation. Dr. Horvath holds a pH.D. degree inmedical science from Harvard, where he conducted research on human reactions toenvironmental stresses, including heat. He performed the same kind of research for themilitary during World War II, and he was subsequently on the faculties of a number ofmedical schools. He also worked for Alcoa, where he and Dr. Kinmon worked together on theproblems caused by hot environments.At Dr. Kinmon’s suggestion, Industrial Glass had one of itssenior industrial engineers conduct a time motion study of an operator’s activities. Heperformed an 8-hour study, covering four hours on two consecutive days, observing theoperator of machine number 8, the same machine observed by the Secretary’s expert, andvideotaping his activities. He identified fourteen specific tasks that were performedseveral times during the course of the study plus miscellaneous tasks that were notrepeated, all of which he pin into one category. Listing these activities, he then used astopwatch to measure how much time the operator spent during the 8-hour period performingeach task. He also determined how many times each task was performed during the study.Using this information, he was then able to determine the amount of time spent, on theaverage, on each task per day and per hour.The time motion study contains diagrams of the area where itwas conducted, identifying where each of the tasks was performed. It also contains abreakdown of how many minutes were spent on each of the tasks for each hour of the studyand two composite typical hours. one with and one without a break. The engineer admittedthat averaging the times would not give an accurate picture of the operator’s activities,because it eliminates the peaks and valleys of certain activities, but he stated that hedid not observe a great variance from hour to hour during the periods studied. Throughoutthe study, there were the sort of minor breakdowns and jams that occur routinely, and themachine did have a breakdown on one of the days, requiring more activity close to themachine, the source of the heat. In contrast to Dr. Spaul’s 20-20-20 model, the fourteenspecific tasks identified by Industrial Glass’ time\/motion study required between 20seconds and 3 minutes,10 seconds per occurrence. and required a total of between 3 minutesand 1 hour, 40 minutes over the course of an 8-hour shift.Both of the experts retained by Industrial Glass visited theplant. One of them, Dr. Dinman, observed the operation for between four and five hours,while the other, Dr. Horvath, observed the last three or four hours of one shift and thefirst two hours of the next shift. Both questioned the operators about their activitiesand satisfied themselves that the conditions they were observing were typical. Each ofthem studied the videotapes made during the time\/motion study to help them determine theprecise motions involved in the activities of the operator.Using the videotapes and the time\/motion study, the expertseach performed a workload analysis similar to the one performed by Dr. Spaul. Theyanalyzed each task, breaking it down into its various motions, determining the workloadfor each element of each task, then adding them to get the workload for the entire task.The Kcals for each task were multiplied by the minutes per hour spent performing thattask, and those products were then totaled. Dr. Dinman calculated the operator’s exertionsas ranging from 132 to 167 Kcals\/hour, while Dr. Horvath calculated them at 136 to 138Kcals\/hour. Based on these figures, the company’s experts both concluded that theoperator’s actual metabolic workload was substantially less than estimated by the IH andDr. Spaul. Both of them stated that, even if they accepted the Secretary’s temperaturemeasurements and calculations of the environmental heat load as correct. [[3]] theemployees were not exposed to a total heat load great enough to cause heat stress.Explaining how he reach his conclusion, the first expert, Dr.Dinman, stated that it is important to identify all locations where an employee would workduring the course of his job and to determine the temperatures at each of those locations.He explained that, if the temperatures vary from location to location, it is necessary todetermine how much time the employee spends in each location. Dr. Dinman testified thatthe time\/motion study was useful to determine the locations where the employees worked,the amounts of time spent in each location, and the metabolic heat generated by theemployee’s activities.The other expert, Dr. Horvath, stated that a person’s heartrate is an indicator of how much he is exerting himself. While he was at the IndustrialGlass plant, Dr. Horvath took the pulse of the operator on a number of occasions,comparing the rates after certain tasks with the resting rate. The difference was soslight that he concluded that the operator’s duties were not strenuous. Dr. Horvathreinforced this conclusion in the laboratory, where he and his staff copied the variousmotions involved in some of the operator’s tasks, measuring the carbon dioxide produced.Even though the lab had highly sophisticated equipment, he could not measure enough of anincrease to be considered significant.Dr. Horvath stated that he had been involved in numeroustime\/motion studies himself and could tell that the company’s in-house study had beencarefully done.\u00a0 Dr. Horvath noted that he considered the company’s study\”informative,\” but he knowledge that a longer study would likely have included awider range of conditions and tasks not performed frequently.\u00a0 He did, however, havethe benefit of a 12-day time\/motion study performed by another glass company which hadretained him as a consultant.\u00a0 That company used the same kind of machinery asIndustrial Glass, and its employees’ activities were similar.\u00a0 He testified that hispreliminary analysis of that study produced a metabolic expenditure very close to thefigures he got in this case.Both of the experts presented by the company had worked forAlcoa, where there were high levels of heat radiated by large amounts (750 pounds) ofmolten aluminum.[[4]]\u00a0 The temperature of the bottles coming out of the molds isapproximately the same as that of the molten aluminum with which the two witnesses werefamiliar.\u00a0 Both of the company’s experts had served on the panel which had developedthe NIOSH recommendations and were familiar with the studies underlying the figures andthe process by which figures had been decided.\u00a0 Both were very critical of the seriesof compromises involved in developing the recommendations, asserting that there was littleor no scientific basis for some of the recommendations, particularly the conclusion,represented by the curve on the graph, that continuous work at an energy expenditure belowthe 200-Kcal level exposes employees to heat stress.C. THE NON-EXPERT EVIDENCEThe Secretary presented as witnesses a number of IndustrialGlass employees, who testified that they had experienced various ailments that theyattributed to the heat, including headaches, dizziness, nausea, muscle cramps, andproblems with their vision.\u00a0 For example, the union president testified that he hadfainted twice.\u00a0 The first occasion was approximately ten years before the hearing,when he felt hot, went to get a drink of water, and collapsed.\u00a0 The second incidentoccurred about a week before the hearing was held, while he was in the employees’ showerroom talking to some other employees.\u00a0 He felt weak and told the other employees thathe was going into the other room to lie down.\u00a0 As he started to go into the otherroom, he collapsed.\u00a0 On both occasion’s, the company’s nursing staff was called andtreated him.\u00a0 On the second occasion, the nurse called an ambulance for him, but herefused to go to the hospital. In general, the employees testified, they did not seektreatment from the company’s nursing staff or from a physician.\u00a0 In response to anOSHA subpoena, the nursing staff reviewed its records and found only seven reportedincidents in a 4 1\/2 year period which might be attributable to the heat.[[5]] Some of the employees testified that, when they or otheremployees had brought thermometers to the plant from home and had placed them around thework area, some of the thermometers had hit their maximum readings, and that one that wascalibrated up to 180 F reached 160 F. [[6]]\u00a0 There was also testimony that theclothing of some employees had caught fire from the heat.\u00a0 A witness for the company,who had been an operator himself, testified, however, that clothing cannot catch firesolely from the heat; it can happen only if the clothes come into contact with the hotglass when the bottles come out of the mold onto the conveyor.\u00a0 In his experiencethis occurs only rarely. [[7]]V. ANALYSISAs noted above, to prove a violation of section 5(a)(l), theSecretary must show that the employees were exposed to a hazard in the workplace. \u00a0The Secretary presented both expert and employee testimony addressing this element. \u00a0Having reviewed the record, we find that the Secretary has not established by apreponderance of the evidence that there was a hazard present in the Industrial Glassforming department.The citation identified the hazard as \”excessive heatstress\” (emphasis added), perhaps in recognition that at least some amount of heatstress is an inevitable part of this operation.\u00a0 In her subsequent complaint, theSecretary alleged: \”Respondent violated ? 5(a)(l) of the Act in that it allowed itsemployees in the ‘hot end’ of the glass plant to be exposed to excessive heat stress whileoperating and maintaining equipment used to manufacture glass bottles.\”\u00a0 Thebulk of the evidence the Secretary presented to prove that there was a hazard was theexpert testimony that the employees were exposed to a combination of environmental andmetabolic heat that was excessive because it exceeded the limits permitted under theNIOSH, ACGIH, and AlHA documents, while the company’s primary evidence that there was nohazard is the testimony of its two experts.\u00a0 All three expert witnesses were highlyqualified, and the opinions of the company’s experts are in direct conflict with thosepresented by the Secretary’s, making it difficult to evaluate the voluminous evidence inthis controversy.\u00a0 Had the company not presented such a strong rebuttal of theSecretary’s case, we might have found the testimony of the Secretary’s expert that theemployees were exposed to the hazard of heat stress to be persuasive.Two factors weigh heavily in our decision in favor of thecompany, however: the eminence of its experts; and the fact that their testimony was basedon a time\/motion study that identified four or five times as many tasks as were assumed inthe model relied on by the Secretary’s expert.\u00a0 In view of the company’s time\/motionstudy, we simply cannot give much weight to the portion of the Secretary’s evidence thatwas predicated on the assumption that the operators spent twenty minutes of each hour atone location performing one task, twenty minutes at another location performing anothertask, and twenty minutes in a third location doing a third task.It is clear from the record that the operator’s duties are muchmore varied than assumed by Dr. Spaul’s -20-20-20 model and that, contrary to theassumption by the Secretary’s expert, an operator spends far more time in locations thatare removed from the bottles and the machines, which are the source of the heat.\u00a0 AsDr. Dinman testified, a study which records the operator’s minute-by-minute activities andanalyzes them job component by job component will be more precise than the rough estimatesrelied on by the Secretary.[[8]]\u00a0 Because we have no heat measurements for theseother locations, some of which are several feet from the machines, we cannot determinewhat the temperatures are in those locations.\u00a0 Since we are not able to ascertain thelevels of the employees’ heat exposure at each work station, we cannot make anydetermination of their overall environmental heat exposure.Even if we assume arguendo that exceeding the exposure limitsset out in NIOSH’s recommended standard and in the ACGIH and AIHA publications would provethat there was a hazard within the meaning of section 5(a)(1) based on the information inthis record, we are unable to determine whether an employee’s total heat exposure would infact exceed those levels of heat exposure.\u00a0 Because the testimony of the Secretary’sexpert was based on temperature readings that did not accurately reflect the movements ofthe employees around the forming department, the Secretary has not carried her burden ofestablishing that the levels of environmental heat were excessive.We are also unable to give much weight to the calculations ofmetabolic heat by the Secretary’s expert, who testified that he frequently doesphysiological workload assessments of the sort performed by Dr. Horvath at the plant andin the laboratory, but conceded that he elected to use the tables in this case becausesuch assessments are time-consuming and tedious.\u00a0 Dr. Horvath testified that it wasit mistake for the Secretary to assume so few tasks.\u00a0 The company has argued that theSecretary’s calculations of the employees’ metabolic workload were based on inadequateinformation because they assumed only three or four activities.\u00a0 The judge agreedwith that argument and we do as well.\u00a0 The company’s experts, working separately,both arrived at significantly lower workload levels.\u00a0 Given the more detailedinformation on which their analyses were based and the more precise methods used to assessthe energy expenditure, we are inclined to give them more weight than the calculations ofthe Secretary’s expert.\u00a0 We note that Dr. Spaul and the IH both admitted that theemployees gave them widely varying estimates of they time they spent performing thedifferent tasks on which they based their metabolic heat estimates.\u00a0 We thereforeaccept the metabolic heat estimates of the company’s experts rather than those of theSecretary’s expert and the IH.The Secretary has emphasized that one of the company’s expertstestified that the work done by an operator was about twice as strenuous as driving a car.\u00a0 For a number of reasons we are not certain exactly what that testimony means or howmuch weight to give.First, the witness also testified hat the figure given fordriving a car in the ASGIH booklet seemed much too high to him.[[9]]\u00a0 In addition,both parties presented evidence that there was a base figure for a body at complete rest,although the figures presented by the Parties differ.\u00a0 Neither party, has explainedwhether \”twice as strenuous\” is calculated by subtracting this base numberfirst.\u00a0 Then doubling the remainder, of by doubling the actual figure for driving acar. The Secretary’s reply brief simply doubles the figure given in the ACGIH booklet, butit is not at all clear to us that doubling is the proper way to make the calculation.\u00a0 The calculations in the NIOSH recommendation suggest that the basal metabolismremains constant and that additions are made to that figure depending on the activity andthe position in which the activity is performed.\u00a0 The ACGIH document is not so clear,however, We therefore do not know whether the calculation in the Secretary’s brief iscorrect.\u00a0 Because we cannot determine on this record exactly what \”twice asstrenuous\” means, we do not know how much weight to accord that statement.The Secretary has argued that one of the company’s supervisorstestified that the work in the forming department was comparable to heavy construction,which he had previously done.\u00a0 A review of that testimony, however, reveals that thewitness was not referring to how strenuous the work was.\u00a0 What he said was that theheat was comparable to being on a metal roof in the summer.\u00a0 His testimony thereforedoes not contradict that of the company’s experts.The Secretary has further asserted that the NIOSH, ACGIH, andAIHA documents establish a maximum WBGT level of 86 F for employees performing continuouslight work at a level below 200 Kcals per hour.\u00a0 We find, however, that, even if weassume that exceeding this recommended limit would he a hazard, the Secretary has notestablished that the cited employees were performing \”continuous work\”. \u00a0Although the Secretary’s expert testified that it was his impression that the employeeswere under a continuous workload, the testimony of the employees shows that, to thecontrary, they do rest between activities, and they can get away from the source of theheat even while they are performing their duties.\u00a0 The Secretary’s expert may havebelieved that the operators’ activities placed them in the \”continuous work\”category, but the record makes it clear that working without taking an official breakwithin the meaning of the employment contract is not the same as working without pause orrest.\u00a0 The employees did not engage in constant action but took brief breaks betweentasks and even rested momentarily during a task.\u00a0 We therefore find that IndustrialGlass’s employees did not fall within the \”continuous work\” category as theSecretary claims.We must note that we would be hesitant to hold that exceedingthose levels is, in and of itself, proof of exposure to a hazard.\u00a0 The Secretaryasserts that they are the dominant guidelines on heat stress and are followed by allprofessional industrial hygienists.\u00a0 Dr. Spaul, the Secretary’s own expert witness,testified, however, that all three documents were essentially copied from each other andthat they all contained a substantial safety margin.\u00a0 While it would be veryappropriate for the Secretary to include a safety margin in an OSHA standard, the presenceof a safety margin in the documents she relied on to prove a hazard here gives usreservations as to whether evidence that the limits in the NIOSH document were exceededwould, in fact, prove that there was a hazard.[[10]]\u00a0 Furthermore, Dr. Horvathtestified that some of the work on which the NIOSH curves were based had subsequently beendiscredited to a large extent, and both of the company’s experts testified that there wasinadequate scientific information to support some of the assumptions shown on the graphsin these documents.\u00a0 We therefore have considerable reservations about basing aviolation of section 5(a)(l) or those guidelines.\u00a0 Because we are deciding this casebased on the insufficiency of the Secretary’s evidence, however, we need not decidewhether a violation of section 5(a)(l) would have been established if the Secretary hadproved that the limits in the documents had been exceeded. [[11]]Having concluded that the Secretary failed to establish thepresence of a hazard by expert testimony, we must examine the other evidence presented bythe Secretary, namely the testimony of the employees.\u00a0 While the employee testimonyregarding the difficulties they experienced because of the hot working conditions troublesus because it clearly shows that this is an uncomfortable working environment and thatemployees do suffer from the effects of the heat, [[12]] the citation’s identification ofthe hazard as excessive heat stress suggests that the Secretary recognizes that somedegree of discomfort is inherent in the job.\u00a0 The testimony as to headaches,dizziness, nausea, fatigue, muscle cramps, and even the two instances of fainting must bebalanced against the fact that many of the abatement measures sought by the Secretary werealready in place to one degree or another.We note that Congress intended that an employer’s duty to freeits workplace of hazards under section 5(a)(l) to be an achievable one.\u00a0 Nat’l Realty& Constr. Co. v. OSHRC, 489 F.2d 1257, 1265-66 (D.C. Cir. 1973).\u00a0 Here,Industrial Glass had installed insulation on the melting tanks.\u00a0 Near every machine,there was at least one large blower and a water cooler.\u00a0 The company had moved themachines farther apart, which reduced the concentration of heat.\u00a0 There wereelectrolyte drinks available to the employees, both through the nursing staff and in itvending machine in the break room, which was air conditioned.\u00a0 The nurses also hadelectrolyte tablets available for any employee who suffered from the effects of the heat.\u00a0 Before a new employee was hired for the forming department, the nursing staff tooka medical history and performed an assessment of the individual’s medical fitness to workin a hot environment.\u00a0 If they did not find that the candidate was medicallysuitable, they informed the personnel department.\u00a0 There was also a de factoacclimatization by virtue of the one-week orientation that was part of a new employee’straining.\u00a0 There wits already established a \”buddy system\” among theemployees of watching out for each other and relieving, an employee who began to beaffected by the heat. Also, there was testimony that, on at least one occasion the foremansent an employee home when he had difficulty with the heat rather than allow him to beexposed to excessive heat.\u00a0 We realize that these measures do not absolutelyguarantee that an employee will never suffer from exposure to the heat, but the recordshows that it is virtually impossible to eliminate all exposure to high temperatures inthis Job.[[13]]We recognize, as the secretary apparently did, that the workingconditions in the forming department are, to some extent, an inevitable part of this kindof work.\u00a0 The employees who testified appear to have considered the conditions to beuncomfortable rather than hazardous. The employees who testified that they sufferedvarious ailments from the heat admitted that they did not seek any medical help, and theunion officer who fainted twice refused to go to the hospital even though an ambulance hadbeen called for him.\u00a0 It therefore appears that the employees considered the heatconditions to be more of a discomfort than a health hazard.[[14]]\u00a0 As noted above,the jobs in the forming department, which involve higher pay, are considered desirable andare highly sought after by Industrial Glass employees who work in the packagingdepartment.\u00a0 They are filled on the basis of seniority unless an experiencedglassmaker is hired.Accordingly, based on the expect testimony and the measurespresent in the forming department to reduce employee exposure to heat and to alleviate itseffects, we conclude that the Secretary has failed to prove by a preponderance of theevidence that the working conditions in the forming department presented a hazard withinthe meaning of section 5(a)(1) of the Act.VI. CONCLUSIONWe recognize that excessive exposure to heat can be a hazard,but the record in this case shows that the company has made an effort to alleviate theeffects of the hot working conditions in the forming department.\u00a0 We find here thatthe Secretary has failed to establish by a preponderance of the evidence that the workingconditions in the forming department constituted a hazard that was likely to cause seriousharm to the health of the employees.\u00a0 For these reasons, we conclude, as the judgedid, that the Secretary has failed to prove that Industrial Glass committed a violation ofsection 5(a)(1) of the Act by exposing its employees to the hazard of heat stress.We therefore hold that the Secretary has failed to carry herburden of proving that there was a heat stress hazard in the Industrial Glass formingdepartment.\u00a0 Accordingly, we affirm the judge’s decision vacating the citation.Edwin G. Foulke. Jr. ChairmanDonald G. Wiseman CommissionerVelma Montoya CommissionerDated: April 21, 1992SECRETARY OF LABOR, Complainant,v.INDUSTRIAL GLASS, Respondent, andGLASS, MOLDERS, PLASTIC, POTTERY AND ALLIED WORKERS, LOCAL 208,Authorized Employee Representative.OSHRC Docket No. 88-348APPEARANCES: Stephen J. Simko, Jr., Esquire, Office of the Solicitor, U. S.Department of Labor, Atlanta, Georgia, on behalf of complainant.William B. deMeza, Esquire, Holland and Knight, Tampa, Florida,on behalf of respondent.Mr. John Ward, President, Glass Molders, Plastic, Pottery and Allied Workers, Local 208,Bradenton, Florida, on behalf of the authorized employee representative.DECISION AND ORDERSPARKS, Judge:\u00a0\u00a0\u00a0\u00a0 Respondent, Industrial Glass, contests a citationfor the serious violation of section 5(a) (1) [[1]] of the Occupational Safety and HealthAct (\”Act\”) for allowing its employees in the Forming Department to be exposedto excessive heat stress while operating and maintaining equipment used to manufactureglass bottles. The case was ably tried and briefed by counsel, and extensive testimony anddocumentary evidence were received into the record.I.Industrial Glass is a division of Tropicana Products, Inc.,which operates several facilities located on 214 acres of land in Bradenton, Florida.Industrial Glass manufactures glass bottles in various sizes in three glass plants inBradenton, where approximately 400 glass unit workers are employed (Tr. 28- 29).The Forming Department in Plant 2 contains four independentsections (\”I.S.\”) glass making machines called \”5 Shop,\” \”6Shop,\” \”7 Shop,\” and \”8 Shop\” (Tr. 97-98, 773).\u00a0 Employeesin the Forming Department work seven-day rotating shifts. They work one shift sevenstraight days and then rotate to another shift or off duty. Industrial Glass runs threeshifts each day, seven days a week. Shifts are 8:00 a.m. to 4:00 p.m., 4:00 p.m. to 12:00a.m., and 12:00 a.m. to 9:00 a.m. Plant 2 employs seven hourly employees per shift: fouroperators, two upkeep mechanics, and one floor attendant (Tr. 26-27, 783, 824-825).Plant 2 shops produce between 100 and 294 bottles per minute(Tr. 39). To produce the glass bottles, the raw sand batch and glass cullet mixture ismelted in the tank above the I.S. machine. The glass at that point is between 2000 and2100 degrees Fahrenheit. The molten glass drops down and is sheared into gobs through thefeeder into the molds. Two gobs drop into each mold. The gob is formed into a parason, agob with a bubble in it, and a finish, the part of the bottle where the bottle where thecap is attached. The bottle is now upside down. Air is blown on the outside to form andcool the glass. The glass is then inverted into the mold. The mold closes around it andcompressed air is blown into the bottle to form it. The mold then opens and the bottle ispushed onto the conveyor and proceeds down the inspection light and the lehr. The lehrperforms annealing, a gradual cooling of the glass. The glass is molded at about 1200degrees Fahrenheit. When it is placed on the conveyor, its temperature is between 700 and900 degrees Fahrenheit. The smaller bottles are cooler. The largest bottle made on thesemachines is a 1.75-liter liquor bottle. The temperature of this bottle is about 850degrees Fahrenheit coming onto the conveyor. At the inspection light, the temperature ofthe bottle drops to 725 degrees Fahrenheit; and, when entering the lehr, the bottletemperature is 600 degrees Fahrenheit (Tr. 775-783, 800-801). The operators’ duties include observation of the operation ofthe glass making machine, quality control checks by testing bottles, swabbing the moldswith graphite oil front and back (doping), assisting on clearing jam ups and helping theupkeep men to change molds and repair machines if needed. Operators usually work 1.5 to 5feet from the molds (Tr. 40-46).The upkeepmen’s duties include working on and repairing machinebreakdowns, changing molds, fixing defects in the glass, working on the tanks that meltthe glass, repairing and maintaining the feeders and relieving operators for breaks. Eachupkeep person is responsible for two machines. Duties require these employees to be nextto the machines (T. 59-61, 259-260).The floor attendants’ duties are to clean glass from underneaththe machines, keep glass off of the floor, keep the barrels dumped out, and see to theneeds of the operators and upkeep people. Their work often requires the floor attendantsto work close to the machines (Tr. 287-288).Forming Department employees receive two 15-minute breaks and a20-minute lunch break during each eight-hour shift (Tr. 107).The break room is airconditioned (Tr. 104).Industrial Glass employs four registered nurses who work on theplant premises. The nurses do not work the 12:00 a.m. to 8:00 a.m. shift or any weekendshifts (Tr. 26-27). Industrial Glass does not have physicians on the premises but usesdoctors on call in the community for medical conditions and accidents or injuries (Tr.149).OSHA Industrial Hygienist Byron Blanke began his inspection ofIndustrial Glass’ facilities on August 26, 1987, pursuant to a complaint received in hisoffice (Tr. 368). Blanke took temperature measurements at several locations throughout thefacilities. He returned to the facilities on September 1, 1987, and took additionalreadings (Tr. 368-371). As a result of Blank’s inspection, Industrial Glass was issued acitation for the violation of ? 5(a)(1) on January 13, 1988. II.In order to establish a section 5(a)(1) violation, theSecretary must prove: (1) the employer failed to render its workplace free of a hazard,(2) the hazard was recognized either by the cited employer or generally within theemployer’s industry, (3) the hazard was causing or was likely to cause death or seriousphysical harm, and (4) there was a feasible means by which the employer could haveeliminated or materially reduced the hazard.The Duriron Co., 83 OSAHRC 22\/A2, 11 BNA OSHC 1405, 1407, 1983CCH OSHD ? 26,527 (No. 77-2874, 1983), affirmed 750 F.2d 28 (6th Cir. 1984).The Secretary alleges that Industrial Glass failed to renderPlant 2 free of excessive heat in the Forming Department, where operators, upkeepmechanics, and floor attendants were exposed. Industrial Glass contends that whileconditions in the Forming Department may have been uncomfortable, they did not rise to thelevel of a recognized hazard likely to cause death or serious injury. If excessive heatexposure did exist, Industrial Glass’ employees were put at a significant risk.Exposure to excessive heat can result in heat exhaustion andheat stroke. At high temperatures, the body circulates great amounts of blood to the skinin an effort to eliminate heat through perspiration. As a result, less blood is circulatedto the body’s vital organs, including the brain. Heat exhaustion can lead to dizziness,nausea, and eventual collapse. If not treated promptly, a person suffering from neatexhaustion could suffer brain damage.Beyond heat exhaustion is heat stroke…. [D]uring heat strokethe body stops sweating, making it impossible to eliminate heat. The body temperature mayrise to a dangerously high level and cause death.Id. at 1406.Several Industrial Glass employees testified as to theconditions in the Forming Department. They established that, although their union contractsince 1983 had called for a heat relief break in addition to the morning, lunch, andafternoon break, operators did not start receiving a heat relief break until one and ahalf months before the August, 1988, hearing. Upkeep mechanics and floor attendants werestill not receiving heat relief breaks at the time of the hearing (Ex. C-1, C-2; Tr. 64,187, 215, 317). The employees also testified that at one time the employees in the FormingDepartment started bringing in various home thermometers, including baking and poolthermometers, and hung them around the work area. The thermometers were eventually takendown by supervisory personnel, but not before the employees observed readings of 140 to160 F. (Tr. 118, 190-191, 219-225, 269).Several employees related instances where they experienceddiscomfort which they attributed to the excessive heat. John Ward, an upkeep mechanic andunion representative, testified that just two weeks prior to the hearing, he fainted dueto the heat after working six and a half to seven hours in front of the machines (Tr.73-74):I was talking to several of my committee members in the showerroom. I had a bad headache, I was sweating, I was burning up, I got severe pains in theback of my head, and I told them I was going to lay down. I started into the other room inthe shower room to lay down and I couldn’t see. And I ended up on the floor.Ward was treated by a staff nurse. He did not consult aphysician regarding this incident so there was no confirmation that his distress wasattributable to excessive heat in the workplace (Tr. 124-125).Ronald Sykes worked as a floor attendant for Industrial Glassfor six months, including the summer of 1987. He described the conditions as follows (Tr.189):Well, especially this time of year, it’s real hot. Once in awhile, you’d have a kind of dizzy spell. Like, you know, it would be so hot, you wouldjust have to back away and just stop for a while . . .\u00a0 You were always soaked withsweat or something in there . . . . Once in a while maybe, .you know, depending on, Iguess, the humidity or whatever, just different things, dizziness, stuff like that.Sykes never went to the staff nurses or sought medicaltreatment with regard to any of the symptoms he mentioned (Tr. 192). The company providedwater, fans and an air conditioned break room, but the environment near the machines wasextremely hot.The testimony of the employees establishes that the heat in theForming Department at times was oppressive but standing alone, does not prove that theheat was so excessive as to excessive injury. The thermometers that the employees broughtin were for home use and not calibrated to the degree of accuracy necessary to establishtheir readings. Helen Heatherington, a staff nurse for Industrial Glass for eight years,testified that employees from the Forming Department sought treatment from the nursingstaff less frequently than employees from other departments (Tr. 175). A medical recordreview prepared by the head nurse, Edna Davis, for the period from January 1984 to June1988, disclosed that a total of five employees came to) the nurses a total of seven timescomplaining of symptoms that may have been heat related (Ex. C- 12). None of theseemployees ever consulted a physician with regards to their complaints, and no medicalevidence exists that could support the employees contentions that their complaints werecaused by excessive heat. As Industrial Glass pointed out at the hearing and in itsposthearing brief, symptoms of heat stress are similar to symptoms of other ailments,including the flu and hangovers.Turning from the employee witnesses’ testimony, then, it isnecessary to evaluate the testimony of the expert witnesses, who sought to calculate theamount of heat stress present in the Forming Department. The standard instrument fortesting heat stress is the Wet Bulb Globe Thermometer (\”WBGT\”). The WBGT takesinto account humidity and air movement (the natural wet bulb reading (\”NWB\”)),and air velocity and air temperature (the black globe reading (\”GLOBE\”)] (Ex.C-6, pp. 3,150; Tr. 464). The calculation for WBGT for indoors is (Ex. C-22, p.5):WBGT = 0.7 NWB + 0.3 GLOBEOn September 1, 1987, Compliance Officer Blanke took eightmeasurements in the Forming Department, which ranged from a low of 83.4 F. to a high of101.2 F. for WBGT (Ex. C-15). Dr. Wilbur Spaul, the Secretary’s expert witness, who holdsa Ph.D. in Environmental Health Sciences, visited Plant 2 on June 15, 1988, and took hisown WBGT measurements (Tr.469). Dr. Spaul was knowledgeable, conscientious and convincing.His testimony was defective only in that he did not make or was not allowed to make, thedetailed investigative findings as was respondent’s expert witnesses. Spaul calculatedthat the average ‘WBGT for machine No. 8 was 4 F. based on a one-hour time-weightedaverage (Tr. 507, 510)Dr. Spaul spoke with Steven Looby, the safety manager forIndustrial Glass, who informed Spaul that during an average hour, operators spent 20minutes at the operators’ work station on the platform, 20 minutes at the test stand, andanother 20 minutes in the general area of the machine (Tr. 506). Based upon Looby’sestimate and his conversations with employees, Dr. Spaul concluded that operators wereunder a continuous workload (Tr. 490). Dr. Spaul also called several glass plants andspoke with the safety managers to get their estimates of their operators’ work\/restschedules (Tr. 493). Although information from these sources was helpful, it is notafforded the weight given to the time and motion studies offered by respondent and reliedupon by its expert witnesses.Dr. Spaul used three guidelines in making his calculationsafter ascertaining the WBGT; (1) the American Conference of Governmental IndustrialHygienists (\”ACGIH\”), Threshold Limit Values and Biological Indices for1986-1987 (Ex. C-4); (2) National Association for Occupational Safety and Health(\”NIOSH\”), \”Criteria for a Recommended Standard . . . Occupational Exposureto Hot Environments: Revised Criteria 1986\” (Ex. C-6); and (3) American IndustrialHygiene Association (\”AIHA\”), \”Engineering Field Reference Manual\”(Ex. R-9: Tr. 473-479). Respondent’s expert witnesses questioned the reliability of theguidelines, contending there were inadequate studies to support the conclusions but noreasonable alternative was suggested. They are endorsed by the leading organizations inthe field.Dr.Spaul testified that heat stress is calculated by addingmetabolic heat to environmental heat, then subtracting the heat lost through evaporation(Tr. 471- 473). Metabolic workload is calculated in kilocalories per hour(\”Kcal\/hr\”). AIHA, ACGIH, and NIOSH define light work as work up to 200 Kcal\/hr(Ex. C-4, p. 70). Dr. Spaul determined that the average level of energy required toperform the operators’ job was 200 Kcal\/hr (Tr. 518-525). His actual readings ranged from190 Kcal\/hr to over 300 Kcal\/hr (Ex. C-22, p. 13; Tr. 490, 492, 495, 510, 519).ACGIH and NIOSH have established the maximum WBGT to whichemployees may safely be exposed at any metabolic workload above 200 Kcal\/hr. The maximumWBGT for a continuous workload of 200 Kcal\/hr is 86 F. (Ex. C-4, p. 72, figure 1). Basedupon his calculations of the WBGT and the metabolic workload, Dr. Spaul concluded that theoperators in Industrial Glass’ Forming Department were exposed to excessive heat (Tr.469). The weakness in Dr. Spaul’s conclusions results from the underlying determinationthat employees were under a continuous light workload requiring energy use of 200 Kcal\/hr.Industrial Glass presented two expert witnesses, Dr. BertramDinman, a Clinical Professor of occupational Medicine, and Dr. Stephen Horvath, aProfessor of biomedical Engineering (Tr. 673, 840).. Both men have had and distinguishedcareers and are highly regarded in the field of heat effects on the human work capacity.They separately evaluated unimpeached time and motion studies which had been made onemployees in the Forming Department (Tr. 857). They observed two shifts for four or fivehours on two different shifts (Tr. 696). They also reviewed a videotape of an employeeoperating an I.S. machine (Ex. R-2; Tr. 693, 696-697, 765). Dinman and Horvath calculateda total hour-by-hour metabolic workload by determining that an operator performs 15separate tasks in his or her job, and assessing the metabolic workload for each of the 15tasks. The individual workload components were time-weighted and totaled (Tr. 695-702).The greater weight given to the testimony of Drs. Dinman and Horvath is directlyattributable to the greater probativeness of the evidence upon which they based theirconclusions.Dr. Dinman found that the operators’ metabolic workload rangedfrom 132 to 167 Kcal\/hr. Dr. Horvath calculated the workload to be 136 to 138 Kcal\/hr.Both concluded that the metabolic workload was mild (Tr. 857). Dinman and Horvathconcluded that employees in the Forming Department were not exposed to excessive heat.Industrial Glass attacks Dr. Spaul’s calculations as invalidand inaccurate. Industrial Glass notes that Inspector Blanke and Dr. Spaul measuredtemperatures only at selected points around the I.S. machines, and that Spaul onlyCalculated the metabolic workload for operators, ignoring the exposures of upkeepmechanics and floor attendants. Industrial Glass also points out that Dr. Spaul calculatedhis time-weighted averages based on rough estimates given by Looby, safety managers atother glass plants, with no showing that their I.S. machines or employee tasks are similarto those of Industrial Glass. While Dinman and Horvath identified 15 separate tasksperformed by the operators, Spaul broke down the operators’ tasks into only threecategories (Ex. -22, pp. 9-11). However, it is concluded that Dr. Spaul’s testimony is notconvincing only because the facts upon which he relied were inferior in quality andquantity than those available to respondent’s experts.There is much evidence that employees suffered severe heatdiscomfort, especially during the summertime. Although heat is necessary in the glassmaking industry, evidence is lacking that respondent did everything possible to alleviatethose conditions. But the Secretary has not carried her burden of proof on the essentialelement that a hazard did in fact exist. Looked at together, it is evident that IndustrialGlass’ expert testimony was much more specific and comprehensive; and, therefore, moreaccurate and creditable, than that of the Secretary. The Secretary did not prove thatemployees in Industrial Glass’ Forming Department were exposed to excessive heat so as toestablish a hazard under section 5(a)(l). Industrial Glass was, therefore, not inviolation of section 5 (a) (l).The foregoing constitutes the findings of fact in this case.CONCLUSIONS OF LAW1. Respondent is subject to the Act and this proceeding.2. Respondent did not violate section 5(a)(l) of the Act.ORDERThe citation and complaint are dismissed. Dated this 29th day of March, 1989.JOE D. SPARKSJudgeFOOTNOTES: [[1]] Section 5(a)(1) provides \”Each employer shallfurnish to each of his employees employment and a place of employment which are free fromrecognized hazards that are causing or likely to cause death or serious physical harm tohis employees.\”[[2]] In contrast to a household, or dry bulb thermometer, awet bulb thermometer has a bulb that is covered by a saturated cloth. This reading isaffected by the rate of evaporation, which is determined by humidity and air velocity.Another type of device, the global thermometer, is set in a matte black metal sphere andmeasures radiant heat. All the global temperatures taken by the IH and the Secretary’sexpert were higher than the other readings at the same locations, indicating that there isa great deal of radiant heat in the forming department.[[3]] They did, however, question the Secretary estimates ofthe employees exposure to environmental heat because the time motion study showed that theemployees were not limited to three or four locations.[[4]] Dr. Horvath noted that one of the difficulties in makingan accurate measurement of an individual’s heat exposure in a situation like this with ahigh level of radiant heat is that one side of the person may be exposed to a low level ofheat while the other side is exposed to a great deal of heat radiating from the source.[[5]] Both of the incidents involving the union president felloutside the period surveyed by the nursing staff.[[6]] Dr. Horvath cast doubt on these readings, however,because he stated that the thermometers should be shielded from radiant heat sources inorder to get an accurate reading of the air temperature. He testified that, depending onwhere the thermometer was placed, heat radiating at it from all sides could give anartificially high reading.[[7]] The citation alleged the hazard of heat stress. It doesnot mention burns. While there is some evidence that in employee is more likely to beinattentive and bring his clothing into contact with the bottles if he is suffering theeffects of the heat, we cannot say that the citation covers the situation described.[[8]]The Secretary has argued that a time motion study based onfour hours per day over two days is hardly likely to give an accurate reflection of allthe conditions under which an operator will work. We agree. All of the experts were inagreement that a study covering a much longer period would have been more desirable. Thecompany’s. time motion study is, however, the best evidence we have. It is certainly moreaccurate than the estimates relied on by the Secretary’s consultant who admitted that hewould prefer to base his evaluation on observation of the operator’s activities for aminimum of five days rather than on his observation for only 1 1\/2-hours.[[ 9]] In the table of energy expenditure, a substantial rangeis given for activities such as lying at ease, sitting at ease, and casual walking, but asingle figure is given for driving a car. It seems to us, however, that the level ofenergy expended driving an automobile can vary greatly, depending on the type ofautomobile and the road. For example, it seems unlikely that the same amount of energywould he required to drive a car with automatic transmission and cruise control along astraight, flat interstate highway as would he required to drive a standard shift car alonga windy mountain road or in city traffic during rush hour. Given these potentially largedifferences in the amount of energy required to operate different automobiles underdifferent conditions, we cannot say with any confidence that the parties were talkingabout the same activity. We also note that, on the table of energy expenditures in theAIHA Engineering Field Reference Manual, on which the Secretary relies. The value givenfor sitting at ease is substantially higher than the values given for both mechanicaltyping and electrical typing Because we do not understand this seeming incongruity, we donot know how much authority we can attribute to the contents of this table.[10] In 1972, NIOSH recommended that OSHA adopt a standardgoverning exposure to heat, and a panel appointed by OSHA endorsed that recommendation in1974. Nevertheless, OSHA has not adopted a heat stress regulation but has relied here onthe NIOSH criteria and on guidelines issued by two private organizations of industrialhygienists. The essence of the Secretary’s allegation is that the heat exposure limits setout in those documents were exceeded and that the employees were therefore exposed to thehazard of heat stress. The NIOSH standard, however, does not have the force and effect oflaw; failure to comply with it is not in and of itself illegal.[[11]] Contrary to the Secretary’s assertion, the Commission’sdecision in The Duriron Co., 11 BNA OSHC 1405, 1407 n. 2. 1983-84 CCH OSHR 26,527, p.33,798 n. 2 (No. 77-2847.1983), aff’d, 750 F.2d 28 (6th Cir. 1984) does not require adifference result. In that case the Commission found the existence of a hazard based uponevidence other than exceeding the limits, in the NIOSH document and was careful to statethat the document was considered only for the purpose of establishing that the employersindustry had recognized that heat stress was a hazard. Here, the Secretary has attemptedto prove that exceeding the limits set in the documents constituted a hazard.[[12]] The company presented evidence that the effects ofheat-related conditions resemble symptoms caused by the flu, viruses, or other ailments.We are inclined, however, to believe that the employees’ complaints are more likely thannot the result of their very hot working conditions.[[13]]One of the abatement measure proposed by the Secretary inthe citation was a required drinking program for employees in which they would drink waterevery fifteen to twenty minutes. We note that the company’s time motion study shows thatthe employee studied went to the water fountain to get a drink three times an hour inhours he did not get a break and twice an hour when he did have a break during the hour.It would therefore appear that this measure is in effect already in place.[[14]]Although this evidence is not controlling it doesconstitute evidence from the individuals who are most familiar with and most affected bythe cited working conditions. See General Motors Corp. 11 BNA OSHC 2062.2066 1984-x5 CCHOSHD 26.961 pp 34.611-12 (No. 78-1443.1984). aff’d. 764 f.2d 32 (1st Cir. 1985). Wetherefore accord these views some weight and consider them together with the otherevidence on the question of whether the Secretary proved that there was a hazard.[[1]] Section 5(a)(1) of the Act, 29 U.S.C. 654(a)(1),provides:Each employer shall furnish to each of his employees employmentand a place of employment which are free from recognized hazards that are causing or arelikely to cause death or serious physical harm to his employees.”