“UNITED STATES OF AMERICAOCCUPATIONAL SAFETY AND HEALTH REVIEW COMMISSION\u00a0 \u00a0 SECRETARY OF LABOR, \u00a0 ???????????????????????????????????????????? Complainant, \u00a0 ???????????????????????? v. OSHRC DOCKET NO. 13864 W. J. LAZYNSKI, INC., \u00a0 ????????????????????????????????????????????? Respondent. \u00a0 \u00a0December 27, 1979DECISIONBefore CLEARY, Chairman; BARNAKO and COTTINE,Commissioners.BARNAKO, Commissioner:??????????? A July15, 1976, decision of Administrative Law Judge George W. Otto is before theCommission for review pursuant to section 12(j) of the Occupational Safety andHealth Act of 1970,[1]29 U.S.C. ? 661(i). This proceeding involves two serious citations issued toRespondent (Lazynski) charging it with violations of the Secretary?sconstruction standards regulating tunnel and shaft safety. Judge Otto affirmedboth of the citations, which alleged violations of the Act for failure tocomply with the standards at 29 C.F.R. ?? 1926.800(c)(1)(i) and1926.800(c)(2)(i) and (v). He assessed an $800 penalty for each citation. Onreview Lazynski challenges the propriety of the judge?s findings regarding bothof these citations. For the following reasons, we affirm the judge?sdisposition.??????????? TheAlleged Violation Involving the Standard at 29 C.F.R. ? 1926.800(c)(1)(i).[2]??????????? Lazynski,a Wisconsin corporation, is a sewer tunnel contractor. On May 6, 1974, it beganthe construction of a tunnel beneath the Fox River in Green Bay, Wisconsin.After digging a 100 foot deep employee entrance and equipment shaft, Lazynskimined 600 feet of the horizontal tunnel. During this original phase of theconstruction process, its employees were working in ?free? or ?open? air.??????????? OnApril 9, 1975, Lazynski reached a silt pocket, and some water and materialbegan leaking into the tunnel. In order to keep these substances out, Lazynskiproduced a compressed air environment. Compressed air is under greater thanatmospheric pressure. It is normally used when tunneling under conditions ofhigh hydrostatic pressure?pressure which permits either water or soil with ahigh water content to seep into the tunnel. By sealing off a tunnel with an airlock, which equalizes and regulates air pressure, and using low air compressorswith air lines extending into the working chamber, it is possible to produce acompressed air environment. This environment has a stabilizing effect on thesoil, keeping water and gases dissolved in it from seeping into the tunnel.From April 9, 1975, until May 10, 1975, Lazynski operated under compressed airwhich was maintained at 12 pounds per square inch (psi).??????????? Aftermining 700 feet in a compressed air environment, Lazynski decided to decompressthe tunnel in order to return to free air. Lazynski decided to decompressbecause it had completed tunneling under water, where it felt it wouldencounter the worst ground conditions. Decompression took place over theweekend of May 10 to May 12, 1975. It was completed at 6:00 a.m. on May 12. Approximatelyone hour later, six of Lazynski?s eight first shift employees reentered thetunnel to resume its construction. An explosion took place killing fouremployees.??????????? Decompressionis a critical process. Because compressed air is being removed from the atmosphere,gases which are present in the sediment surrounding a tunnel wall are likely toseep in. Some of these gases may be flammable; others, toxic. In the case ofthe tunnel explosion killing four of Lazynski?s employees, subsequent testingrevealed the presence of methane gas.??????????? Methanegas is formed from the anaerobic decomposition[3] of organic matter. Woodchips, shells, and other organic debris of all kinds are a potential source ofmethane, as well as other flammable gases. These materials are found in soillocated under river or lake beds.??????????? Accordingto several witnesses for the Secretary, the Fox River area in which Lazynskiwas mining contains the potential for methane and other flammable gases. Basedon a review of 300 test borings taken in the area within the last eight to tenyears, these witnesses concluded that the presence of wood chips and sea shellsindicate a possible source of methane. A geologist in the area, Thomas Quigley,discovered that clay encapsulated the borings which he analyzed. If thesematerials were to decompose in an oxygen free environment, flammable gaseswould be released and trapped in the subsurface soils.??????????? Lazynski,however, failed to recognize a relationship between the soil environment at theFox River project and the presence of methane. Before commencing constructionof the sewer tunnel, Kenneth Peterson, the company?s president, and TheodoreBudd, the project manager, reviewed the reports of approximately 300 testborings taken in the area.[4] They did not find that anyof these borings indicated the presence of methane gas. Indeed, Theodore Buddsaw wood chips and sea shells in test borings that he studied, and he actuallyencountered some of these materials during construction of the tunnel. However,it did not occur to him that these organic substances might indicate thepresence of methane. Similarly, although he often discovered traces of organicmaterials while tunneling under rivers, Peterson never suspected that they werea potential source of methane gas. Because he had never come into contact witheither the gas or anyone who had encountered it in Wisconsin,[5] he did not analyze theorganic materials from this perspective. Neither Budd nor Peterson inquired ofanyone whether the various reports indicated the potential for flammable ortoxic gases. Instead, they were primarily concerned with the soil bearingcharacteristics or mineability of the tunnel.??????????? Thiswas also true of the independent consultants who took test borings forLazynski. Richard Brissette, a civil engineer, took several test borings forLazynski, and he examined the reports of several others. Although he found noindication of methane gas in his soil analysis, he did not study the boringswith this objective in mind. The company also retained William Perpich, thepresident of Soil Testing Service, to compile a report of the generalized soilconditions in the area of its project. Of the eighty soil borings evaluatedwithin a three-mile stretch, none indicated the presence of methane gas.??????????? Eventhough Lazynski was unaware of the potential for methane gas, it tested theatmosphere for flammable gases during all phases of the tunnel construction.The instruments Lazynski used to perform these tests varied. During theoriginal free air phase of the work Lazynski used instruments capable ofquantitatively testing the atmosphere for the presence of various toxic andflammable gases.[6]While working under compressed air, however, the only device it used to testthe air was a miner?s lamp, which gives no quantitative reading. This devicecontains a flame that flickers or rises when exposed to flammable gases andlowers when exposed to an oxygen deficient atmosphere. The record indicatesthat Lazynski continued to use only the miner?s lamp during decompression.[7] In particular, peroidicchecking of the atmosphere on May 12, while decompression was being completed,was performed with a miner?s lamp; no devices capable of quantitatively testingthe atmosphere were used on that date.[8]??????????? Thewitnesses disagreed as to whether quantitative testing devices could have beenused during all phases of the tunnel work. According to Lazynski?s president,Kenneth Peterson, there were no instruments capable of quantitative testingwhile under compressed air. Although he had investigated the possibility ofusing alternative devices for quantitative testing under a compressed airenvironment, he was not able to discover a more accurate instrument for thispurpose than the nonquantitative miner?s lamp. Peterson, however, did not explainwhether there was any point during decompression when the compressed airatmosphere was sufficiently altered so that the quantitative instruments couldhave been used. The compliance officer, on the other hand, stated thatquantitative instruments could be used during compression and specificallypointed to the W8, manufactured by MSA, as one such instrument.??????????? JudgeOtto concluded that ?respondent could not reasonably have expected to encountermethane gas.? He also agreed with the company that the record did not support afinding that any instrument other than the nonquantitative miner?s lamp couldbe used to test the atmosphere during compression. However, the administrativelaw judge still affirmed the serious section 1926.800(c)(1)(i) citation, but limitedthe period covered by the citation from about 7:00 p.m. on May 11, 1975 untilabout 7:00 a.m. on May 12, 1975.[9] See n. 7, supra. JudgeOtto emphasized the critical nature of the decompression process. He noted thatwhen returning to free air from a compressed air environment, gases trapped inthe surrounding soil, including flammable and toxic gases, could enter thetunnel opening. The judge also noted that during the final hours ofdecompression, ?the air was considered bad, a lamp flickered, a lamp went out.?He, therefore, concluded that ?the events and observations during the 12 hourperiod before the explosion made necessary the conducting of quantitativetesting by appropriate instruments to assure that the required quality andquantity of air was maintained.???????????? Onreview Lazynski argues that the judge erred in finding that the circumstancesknown to it within the final twelve hours prior to the explosion gave noticethat quantitative testing of the atmosphere was necessary. Pointing to JudgeOtto?s finding that the company could not have reasonably expected to encountermethane gas, Lazynski maintains that the judge erred in sustaining theviolation on the basis of last minute changes in the environmental conditionswhich two of its employees noticed but did not report. Lazynski also assertsthat since Judge Otto accepted the testimony that no quantitative instrumentsexist for testing during compression and that, therefore, a miner?s lamp is thebest device available, it was unreasonable for him to expect the tunnelcontractor to quantitatively test during decompression. Finally, Lazynskicontends that the administrative law judge applied an unconstitutionally broadtesting standard to it when it found that the company did not follow therequirement of section 1926.800(c)(1)(i) to test ?as frequently as necessary.?Relying on Cape and Vineyard Division of the New Bedford Gas and EdisonLight Co. v. OSHRC, 512 F.2d 1148 (1st Cir. 1975), Lazynski asserts that inorder for a generally worded standard to pass constitutional muster, it mustproscribe conduct which is considered ?unacceptable in the light of the commonunderstanding and experience of those working in the industry.? It argues thatthe only evidence in the record regarding testing procedures common to theindustry during either compression or decompression was that of the company?spresident Peterson, and that it was using the procedure to which Petersonreferred.??????????? Weconclude that Judge Otto properly found Lazynski in violation of the standardat section 1926.800(c)(1)(i), but limit our holding to a finding that Lazynskiviolated the standard when it failed to quantitatively test the atmosphereimmediately following the completion of decompression at 6:00 a.m. on May 12,1975. Accordingly, before sending its employees back into the free air tunnel,Lazynski should have conducted quantitative tests to assure that the requiredquality and quantity of air in the tunnel was maintained.??????????? Section1926.800(c)(1)(i) requires an employer engaged in tunnelling operations toquantitatively test the atmosphere in its work environment ?as frequently asnecessary to assure that the required quality and quantity of air ismaintained.?[10]The standard specifically mentions carbon monoxide, nitrogen dioxide, flammableor toxic gases, dusts, mists, and fumes as contaminants that may be present inthe air in tunnels and shafts, and places employers engaged in tunnellingoperations on notice that such hazards may be encountered. Thus, the standardrequires employers to anticipate the presence of hazardous gases, among otherthings, and places a general obligation upon them to test. The degree oftesting required is governed by the phrase ?as frequently as necessary toassure that the required quality and quantity of air is maintained.???????????? Lazynskihad tested the atmosphere quantitatively while initially in free air. Duringcompression, it used only a qualitative testing device: the miner?s lamp. Itdid not retest the atmosphere quantitatively before permitting its employees toreenter the free air environment after going off compressed air. The issue thusbecomes whether this state of facts satisfies Lazynski?s obligation to conductquantitative tests ?as frequently as necessary.? We find that it does not.??????????? Atthe outset we note that the phrase ?as frequently as necessary? provides littleif any concrete guidance as to when testing is to be performed. However, wedisagree with Lazynski that the phrase is limited to conduct which is shown tobe contrary to industry practice and custom. In support of its argumentLazynski relies upon the court decision in the Cape & Vineyard case.However, the court in Cape & Vineyard stated that industry practiceis not conclusive and that compliance with a broadly worded standard mayrequire methods of employee protection beyond those customarily used in theindustry. 512 F.2d at 1152. The Commission reached the same conclusion in S &H Riggers and Erectors, Inc., 79 OSAHRC 23\/A2, 7 BNA OSHC 1260, 1979 CCHOSHD ? 23,480 (No. 15855, 1979), appeal filed, No. 79?2358 (5th Cir.June 7, 1979).[11]That case involved the interpretation and application of 29 C.F.R. ?1926.28(a), a standard that requires the use of personal protective equipment,inter alia, ?in all operations where there is an exposure to hazardousconditions.? The Commission concluded that the proper test for determiningwhether a hazardous condition exists within the meaning of section 1926.28(a)is ?whether a reasonable person familiar with the factual circumstancessurrounding the allegedly hazardous condition, including any facts unique to aparticular industry, would recognize a hazard warranting the use of personalprotective equipment.? 7 BNA OSHC at 1263, 1979 CCH OSHD at p. 28,436. TheCommission stated that industry custom and practice were useful referencepoints in determining whether such a reasonable person would recognize ahazard, but the Commission agreed with the court in Cape & Vineyardthat the standard of care commonly used in the industry was not conclusive.Because the frequency of testing requirement of section 800(c)(1)(i) is alsobroadly stated, it is appropriate to apply a similar ?reasonable person? testin determining how frequently testing is required under that standard.??????????? Lazynski?spresident testified that the company?s testing procedures were acceptable inlight of the common understanding and practice of the industry. However, he didnot explain the basis for this conclusion, and the record is devoid of evidencesupporting it. The record shows that Lazynski performed some quantitative testsduring the original free air phase of the work, and used only thenon-quantitative miner?s lamp during compression and decompression. There wasno testimony establishing the frequency with which Lazynski conductedquantitative tests in free air, or any evidence regarding when Lazynskiintended to renew quantitative testing after the completion of decompression. Furthermore,there is no evidence concerning the testing procedures that employers in thetunneling industry normally follow during and after decompression. Theunexplained assertion of Lazynski?s president that Lazynski?s testingprocedures were consistent with industry custom and practice sheds no light onwhether the company?s procedures corresponded to those a reasonable personfamiliar with the factual circumstances surrounding Lazynski?s tunnellingoperation would recognize as adequate. Other evidence, however, demonstratesthat a reasonable person familiar with the facts would have conducted, at aminimum, quantitative tests for harmful gases before sending its employees towork in the tunnel after decompression had been completed.??????????? Thecited standard places employers on notice that flammable or toxic gases andother harmful chemical substances may be present in tunnels under construction.Regardless of whether an employer can anticipate the presence of a particularair contaminant, a reasonable employer would understand that the standardrequires a program of regular quantitative testing, with the frequency oftesting depending on any circumstances that affect the likelihood of thepresence of harmful substances in the tunnel atmosphere.??????????? Therecord shows that decompression is a critical time in a tunnel environmentbecause, among other problems that may arise, gases present in the sedimentsurrounding a tunnel wall are likely to seep in. Lazynski?s presidentacknowledged this. Thus, the period following the completion of decompressionis uniquely one during which the tunnel may contain harmful gases. Whateverfrequency of testing the standard requires at other times, a reasonable personfamiliar with the fact that gases present in the soil can be released into thetunnel after decompression is completed would certainly understand that thestandard requires quantitative testing at that critical time. We thereforeconclude that Lazynski failed to comply with section 1926.800(c)(1)(i) by notconducting quantitative tests between the end of decompression and the time theemployees resumed work in the tunnel.??????????? Ourconclusion that Lazynski violated the standard does not depend upon theforeseeability of the accident as it actually occurred or the foreseeability ofthe presence of a dangerous concentration of methane. Moreover, our holdingdoes not depend upon any changes in the environmental conditions evidenced bythe flickering of the miner?s lamp.[12] And finally it is notinconsistent with Judge Otto?s credibility finding, which we accept,[13] that no quantitativetesting devices could be used during compression, and thus by implication, forat least part of the period of decompression.[14]??????????? Afterconsidering the penalty factors set out in section 17(j) of the Act, we agreewith the judge that an $800 penalty for this violation is appropriate. The Alleged Violation Involving theStandards at 29 C.F.R. ?? 1926.800(c)(2)(i) and (v)[15]??????????? Oneor two ?-inch high air lines provided the sole source of tunnel ventilation forLazynski?s employees during the one-hour period of free air before the fatalaccident on May 12. A high air line is commonly used in the tunneling industryto operate pneumatic equipment.[16] The high air lines ranalongside the tunnel and were loosely connected with nails to its wall.Depending on the particular phase or space of construction, they were locatedbetween 25 and 100 feet back from the face of the tunnel, that is, back fromthe forward wall on which excavation work was being accomplished.??????????? Themanifold valves controlling the air flow through the high air hoses were openedfrom ? to ? of full capacity. Powered by a 900 CFM Ingersoll Rand high aircompressor with a rated capacity of 125 pounds per square inch (psi), each ofthese hoses produced a maximum of 184.6 cubic feet of tunnel air per minute.Thus, the total amount of air supplied to the tunnel was 369.2 cubic feet perminute. The linear velocity of the airflow in the tunnel bore was substantiallyless than 30 feet per minute, and the direction of airflow was not reversible.??????????? Dr.Thomas Richard, a compliance officer for the state of Wisconsin and an expertwitness for the Secretary, testified that the proper mode of ventilation in afree air tunnel utilizes aboveground fans connected to underground ductwork. Inhis opinion, Lazynski should have already installed this system and been usingit to ventilate the tunnel before sending employees into the working chamberfollowing decompression. In such a permanent ventilation system, the ductworkextends vertically from a ground level bore hole, travels down through anaccess shaft, and turns at a right angle before extending into the workingface. Since the fan is reversible, it can either blow fresh air directly to theworking chamber or exhaust dust, fumes, and toxic gases from the tunnel face.Therefore, the system provides quality air for underground workers while itprotects them from dangerous flammable or combustible gases.??????????? Anothercompliance officer, Carlos Gonzales, also stated than an underground ductsystem should have been installed as the tunnel construction proceeded. Becausethe tunnel was short (1200 to 1800 feet), the duct lengths could have beentwenty-four inches in diameter, varying in length from thirty to forty feet.Both witnesses agreed that, without sophisticated purification, the airgenerated by a compressor is not safe for breathing purposes. They also concurredthat reversible fans and ductwork are generally recognized as the proper meansof tunnel ventilation. Even Lazynski?s foreman, Donald Brenton, admitted thatin his fifteen years with the company, he had never been in a tunnel thatrelied solely on high air for ventilation. Kenneth Peterson, Lazynski?spresident, conceded that while there were some filters on the compressor, therewere not enough to take out all impurities. Because of this, he would notrecommend relying on it for more than a few hours.??????????? Thecitation, which was limited to May 12, 1975, subsequent to the removal of airpressure in the tunnel, alleged that Lazynski?s ventilation system violated thestandard in three respects: the total amount of air supplied was less than 200cubic feet per minute for each employee working in the tunnel; the linearvelocity was less than 30 feet per minute; and the direction of air flow wasnot reversible. Judge Otto found that the facts supported all three aspects ofthe violation and affirmed the citation.??????????? Onreview, Lazynski concedes that the ventilation system was nonreversible, butargues that since that fact had nothing to do with the accident, it should notbe found in serious violation of the Act. The company also takes exception tothe other two aspects of the judge?s finding of a violation.??????????? Lazynskiargues that its temporary use of high air substantially complied with section1926.800(c)(2)(i) requiring ?mechanically induced primary ventilation in allwork areas.? Although there are OSHA regulations governing the ventilationprocedures to be used during both a compressed and a free air environment,Lazynski contends that none exists describing the techniques to be employedbetween decompression and the opening of a more complete or permanent ventilatingsystem. The company assumes that because no safety or health standardexplicitly prohibits the use of high air, the Occupational Safety and HealthAdministration tacitly approves of high air as a technique for tunnelventilation. In order to buttress its position that use of high air is arecognized form of ventilation in the tunnel industry, Lazynski points to itsrecent application in pipe jack mining.[17]??????????? Lazynskialso contends that the requirement of section 1926.800(c)(2)(v) to provide 200cubic feet of air per minute for each employee underground ?defies logicalexplanation.? Pointing to the 30 cubic feet requirement in the compressed airstandard at 29 C.F.R. ? 1926.803(i)(1),[18]it asserts that there isno rational basis for the discrepancy between the two tunnel sections. Thecompany admits that a volume of 200 cubic feet might be necessary in large andopen coal mines, but it does not believe that it is warranted in a confinedtunnel area. In any event, Lazynski contends that it was in compliance with thestandard?s volume requirement on the day of the accident. Followingdecompression, the tunnel was literally ?full? of air. At the same time, highair hoses were pumping in additional air. Considering the fact that only a fewminutes lapsed between the entry of first shift employees and the fatalexplosion, there was certainly enough air in the tunnel to satisfy the 200cubic feet mandate.??????????? Finally,Lazynski maintains that the linear velocity requirement of 30 feet per minuteonly applies ?in those tunnels where blasting or rock drilling is conducted orwhere there are other conditions that are likely to produce dusts, fumes,vapors, or gases in harmful quantities.? It argues that Judge Otto made nofinding of gas producing conditions in its tunnel other than to note arelatively insignificant stone drilling which took place approximately twoweeks before the explosion.[19] The company reiteratesits argument made before the judge that this use of a ? pound charge some twoweeks before the explosion for minor drilling purposes was not the 100 poundblasting contemplated by the standard for rock tunnels.??????????? Lazynski?sargument that there are no OSHA regulations describing the ventilation systemto be used between decompression and the opening of a more complete ventilationsystem is without merit. The requirement of section 1926.800(c)(2)(i) thattunnels be provided with mechanically induced primary ventilation in all workareas does not create any lapse in coverage for employees during the period towhich Lazynski refers. Although it is clear that the company could not employ apermanent ventilation system during the periods of compression anddecompression, the record supports Dr. Richard?s opinion that such a systemcould and should have been ready for immediate use subsequent to Lazynski?scompletion of decompression and prior to its employees? reentry into thetunnel. Furthermore, Lazynski?s argument that the standard does not prohibitthe use of high air for ventilation is inapposite. Lazynski violated thestandard, not because it used high air, but because the air flow wasinsufficient.[20]Moreover, the fact that it may be industry practice to use high air during pipejack mining does not affect our conclusion that Lazynski violated the standardhere. The company was not using this mining technique at the Fox River Project.Furthermore, the fact that an industry uses a particular technique does notestablish that its use complies with a specific standard. Lazynski?s evidencethat high air is used during pipe jack mining may mean that employers in thetunneling industry routinely violate the cited standard, not that such aprocedure is adequate. We also note that Peterson stated that high air is usedduring pipe jack mining because it is the only feasible method of ventilationthat can be used in such work. Lazynski does not contend, however, that aventilation system in compliance with the standard could not have been used inthe circumstances of this case. Indeed, the record supports the judge?s findingthat a proper mode of ventilation in a free air tunnel is aboveground fansconnected to underground ductwork.??????????? Thestandard at section 1926.800(c)(2)(v) unconditionally requires a fresh airsupply of at least 200 cubic feet per minute for each employee. On reviewLazynski does not challenge Judge Otto?s finding that the maximum quantity ofair entering the tunnel through each high air hose was 184.6 cubic feet.Therefore, the company?s ventilation system did not meet the quantityrequirement of the standard.??????????? Lazynski?scontention that it complied with this requirement because the tunnel was ?fullof air? before the employees began work lacks merit. The standard is entitled?Ventilation,? and obviously contemplates that it is hazardous for employeesworking in tunnels to simply breathe the ambient air. Thus, in speaking of a?supply of fresh air,? the standard requires that 200 cubic feet per minute peremployee be provided from a source external to the tunnel itself.[21]??????????? Furthermore,the company?s arguments that such a supply was not necessary to assure that itsemployees had adequate air to breathe, and that the standard is illogical inrequiring a greater supply than another standard requires under differentcircumstances, question the wisdom of the standard in establishing the 200cubic feet per minute requirement. The Commission has no authority, however, todecide that the requirement of the standard is too stringent or unnecessary. VanRaalte Co., 76 OSAHRC 48\/B8, 4 BNA OSHC 1151, 1975?76 CCH OSHD ?\u00a020,633(No. 5007, 1976).??????????? Incontrast to the standard?s absolute requirement that 200 cubic feet per minuteper employee be supplied, the standard requires that a linear velocity of 30feet per minute be maintained only when certain conditions are present: whereblasting or rock drilling is conducted or where other conditions are likely toproduce dusts, fumes, vapors, or gases in harmful quantities. Lazynskiinterprets Judge Otto?s decision to find that it violated this requirementbecause of the drilling and blasting it had done before the time of the allegedviolation. It is not clear whether this was, indeed, the judge?s rationale; butin any event, we agree with Lazynski that it was not performing drilling orblasting at the time of the alleged violation. Therefore, a violation of thestandard?s velocity requirement cannot be predicated on such activities.Nevertheless, for the reasons stated below, we conclude that Lazynski violatedthe velocity requirement of the standard.??????????? Thepurpose of the 30 feet per minute velocity requirement is to provide asufficient air flow to dissipate contaminants that would otherwise accumulatein harmful quantities. Unlike the 200 cubic feet per minute volume requirement,which seeks to assure that employees have sufficient fresh air to breathe atall times, the velocity requirement only comes into play when there is anunusual condition that increases the likelihood that dangerous quantities ofair contaminants will be present, and seeks to prevent such contaminants fromaccumulating in quantities that would be harmful. The standard does not requirethe actual presence of a harmful quantity of a contaminant before the requiredventilation velocity must be maintained. See Westinghouse Electric Corp.,79 OSAHRC 28\/B8, 7 BNA OSHC 1318, 1323, n. 13, 1979 CCH OSHD ? 23,542 at p.28,521, n. 13 (No. 13955, 1979), appeal filed, No. 79?1556 (7th Cir. May24, 1979).??????????? Asdiscussed above, in relation to the violation of section 1926.800(c)(1)(i),decompression is a critical time in a tunnel environment, for gases present inthe surrounding soil will be released into the tunnel atmosphere as the excesspressure in the tunnel is removed. Thus, decompression increases the likelihoodof dangerous air contaminants being present in the tunnel, and is a type ofunusual condition that can lead to the presence of harmful quantities of anycontaminant unless a sufficient ventilation velocity is present. We therefore concludethat Lazynski violated the 30 feet per minute requirement of section1926.800(c)(2)(v) by failing to provide this ventilation velocity while itsemployees worked in the tunnel cavity following decompression.??????????? Insummary, we conclude that following the completion of decompression on themorning of May 12, 1975, Lazynski failed to provide each of its six undergroundemployees with 200 cubic feet per minute of reversible primary ventilation at alinear velocity of 30 feet per minute. Therefore, the company committed aserious violation of sections 1926.800(c)(2)(i) and (v). We agree with thejudge that an $800 penalty for this violation is appropriate.??????????? Accordingly,it is ORDERED that the judge?s decision be affirmed.?FOR THE COMMISSION:?Ray H. Darling, Jr.Executive SecretaryDATED: DEC 27, 1979\u00a0\u00a0UNITED STATES OF AMERICAOCCUPATIONAL SAFETY AND HEALTH REVIEW COMMISSION\u00a0 \u00a0 SECRETARY OF LABOR, \u00a0 ???????????????????????????????????????????? Complainant, \u00a0 ???????????????????????? v. OSHRC DOCKET NO. 13864 W. J. LAZYNSKI, INC., \u00a0 ????????????????????????????????????????????? Respondent. \u00a0 \u00a0July 15, 1976DECISION AND ORDERAppearances:Richard J. Fiore, Esq., and Edward J.Moran, Esq., for Complainant\u00a0Robert P. Buellesbach, Esq., for Respondent\u00a0George W. Otto, Judge??????????? Thisis a proceeding pursuant to section 10 of the Occupational Safety and HealthAct of 1970 (29 U.S.C. 651 et seq. hereafter called the Act). On May 12, 1975an explosion in respondent?s tunnel killed four employees and injured others.Following investigation complainant issued citations June 3, 1975 chargingrespondent with serious violation of section 5(a)(2) of the Act by failure tocomply with occupational safety and health standards 29 CFR 1926.800(c)(1)(i)and 29 CFR 1926.800(c)(2)(i)(v), with a proposed penalty of $800 for eachalleged violation. Respondent contests the citation allegations and disputesthe proposed penalty.STIPULATED FACTS??????????? Theparties stipulated that respondent was a corporation with an office and placeof business in Milwaukee, Wisconsin, was engaged in subsurface construction andrelated activities and had a workplace at and about 1496 Bylsby Avenue, GreenBay, Wisconsin, where it was engaged in the construction of a sanitary districtsewer tunnel under contract with the Green Bay Metropolitan Sanitary District.The tunnel was 100[22] feet below the surfaceand traveled horizontally in excess of 1,500 feet, with much of the horizontaldistance constructed directly below the Fox River. There were three shifts,varying between six to eighteen employees, with work duties including mining,concrete form setting and stripping, concrete pouring, cleanup or generalhousekeeping. The foremen were William Alvey, first shift?Wilfred DeGrove,first shift before May 12, 1975?Larry Anderson, second shift?Donald Brenton,third shift.??????????? Respondentbegan the sewer construction activities May 6, 1974 and continued under acompressed air environment from April 9, 1975 until May 10, 1975. Thecompressed air environment was maintained at 121apounds per square inch (psi) during this period.Respondent began decompression May 10, 1975 at 81b psiand completed decompression at 6:00 a.m.on May 12, 1975. About 6:00 a.m. on May 12 the solesource of mechanically induced air was by means of a 900 CFM Ingersoll-Rand portablehigh air compressor; this source was temporary in nature and was not intendedby respondent as a permanent system of ventilation. On May 12 miner?s lamptesting was the sole testing utilized by respondent to test its undergroundatmosphere. At 6:15 a.m.1c on May 12 miner?slamp testing was performed by Donald Brenton, third shift foreman, and AlZalewski, employee. No other tests were conducted at that time. Respondentforemen were responsible for conducting miner?s lamp testing and routinemaintenance of the testing instruments. At 7:00 a.m.1d on May 12 firstshift employees entered the tunnel. At approximately 7:00 a.m. on that date anexplosion occurred within respondent?s tunnel workplace. Subsequent testing byboth parties revealed the presence of methane gas in harmful quantities(Transcript pages 23?30: T 23?30).STANDARDS AND CITATION DESCRIPTIONS29 CFR 1926.800?Tunnels and Shafts2 (c)?Air quality and ventilation(1)?Air quality and quantity(i) Instruments shall be provided to testthe atmosphere quantitatively for carbon monoxide, nitrogen dioxide, flammableor toxic gases, dusts, mists, and fumes that occur in the tunnel or shaft.Tests shall be conducted as frequently as necessary to assure that the requiredquality and quantity of air is maintained. A record of all tests shall bemaintained. and be kept available.?Description?Employer failed to providethat tests be conducted as frequently as necessary to assure that requiredquality and quantity of air is maintained, and that a record of all tests bemaintained and kept available; e.g., Fox River Tunnel, Contract #23 for theGreen Bay Wisconsin Metropolitan Sewerage District. Instruments for conductingsuch tests were available (including flammable gases, carbon monoxide, carbondioxide, oxygen deficiency, etc), but were not utilized as required on orbefore May 12, 1975.29 CFR 1926.800(c)(2)?Ventilation(i) Tunnels shall be provided withmechanically induced primary ventilation in all work areas. The direction ofairflow shall be reversible.?(v) The supply of fresh air shall not beless than 200 cubic feet per minute for each employee underground. The linearvelocity of the air flow in the tunnel bore shall not be less than 30 feet per minutein those tunnels where blasting or rock drilling is conducted or where thereare other conditions that are likely to produce dusts, fumes, vapors, or gasesin harmful quantities.?Description?Employer failed to provide atunnel with mechanically induced primary ventilation in all work areas, thedirection of which ventilation shall be reversible. The supply of fresh airshall not be less than 200 cubic feet per minute for each employee underground.The linear velocity of the air flow in the tunnel bore shall not be less than30 feet per minute in those tunnels where blasting or rock drilling isconducted, or where there are other conditions that are likely to producedusts, fumes, vapors, or gases in harmful quantities; e.g., Fox River Tunnel,Contract #23 for the Green Bay, Wisconsin Metropolitan Sewerage District. Therewas no primary ventilation provided in the tunnel on May 12, 1975, subsequentto the removal of air pressure, other than that provided by partially open highair lines, which were not reversible.?DISCUSSION??????????? 29CFR 1926.800(c)(1)(i):??????????? Throughoutthe tunnel construction until May 12 respondent used the miner?s safety lamp(lamp) continuously. In operation this lamp contains a flame that flickers orrises when exposed to flammable gas and lowers when exposed to oxygendeficiencies. If the lamp is properly maintained, when the flame goes out,there is an indication of insufficient oxygen to sustain human life. The lampgives no percentage reading. It is not an instrument capable of quantitativetesting of the atmosphere. It permits continuous monitoring and serves to alerta knowledgeable employee to any change in the working environment sufficient tosuggest testing, or to impel evacuation (T 152, 185, 192, 203, 246, 331, 444,445, 792).??????????? Thelamp was the only testing instrument used in the tunnel from April 9, 1975until May 10, 1975, the period of operation under 121e psi.Kenneth Peterson, president, testified respondent researched the problem oftesting while under compressed air and was told there was no accurate testingequipment, that respondent buys thousands of dollars? worth of safetyequipment, that its tunnels have been inspected frequently by State inspectorsand inspectors for owners and no other equipment has been suggested (T 709,710, 711). The record is not sufficient to support complainant?s suggestion ordesignation of a specified device other than the lamp for this purpose (T 710).Respondent has made reasonable attempts to determine whether quantitative instrumentshave been available for compressed air environment testing, and has found none.??????????? Respondenthad instruments on the work site to test the atmosphere quantitatively asrequired by the cited standard. These included Universal testing units fornitrogen dioxide, MSA oxygen analyzer, combustible gas meter or indicator,oxygen meter (T 133, 134, 135, 149, 150, 591).??????????? LarryAnderson, foreman, tested with the lamp and ?with the tubes;? about 7:00 p.m.the night before the accident he had taken a combustible gas indicator airsample (T 573, 574). He had not logged the air sampling for the weekend priorto the accident (T 573, 574).??????????? Thestipulated period of decompression was from May 10 to 6:00 a.m.1fon May 12, 1975. The period of decompression is critical. Returning to free airfrom a compressed air environment permits surrounding soil airs to enter thetunnel. Pressure is released off the entire tunnel. Whenever oxygen entersanaerobic2soil,the oxygen may be converted immediately into carbon dioxide, which may enterthe workplace. Hydrogen sulfide may enter also. Flammable gases may come in (T450, 451). Mr. Zalewski and Foreman Brenton worked in the tunnel the nightbefore the accident; shortly before morning the lamp flickered several times;the tunnel air was bad and got worse toward morning, in the morning as theywere leaving the tunnel, one of the lamps went out because it was out of fuel;it was refueled and hung on the elevator door (T 575, 576), Zalewski toldDeGrove before he went down that he thought the air was pretty bad (T 576,577). There is no indication any quantitative testing instrument was used afterforeman Anderson?s sampling at 7:00 p.m. on May 11. Yet during a period ofabout twelve hours prior to the explosion, it appears the air was consideredbad, a lamp flickered, a lamp went out (T 192, 388, 463, 576, 577, 596, 597).??????????? Followingthe explosion, tests at various tunnel locations produced zero to two percent methane,oxygen about 20.5 or 20.9 percent, with no trace of carbon monoxide, carbondioxide or nitrogen dioxide. High air3was flowing in up near the face. There had been tremendous concussion,extensive damage and combustible gas (T 567, 568).??????????? Complainantcontends respondent should have been aware of a methane gas potential, basedupon geologic history and preconstruction subsurface investigation findings.The geologic history and content of eastern Wisconsin, including the Fox Riverand Green Bay areas, is detailed in the record. (T 56, 61?71, 478, 487?492,499, 500, 503, 516, 521, 524?531, 541, 542, C?12). Despite the extensivetestimony upon this subject, the fact remains that the May 12, 1975 explosionwas the first recorded in Wisconsin construction history related to methanegas. No report, map, record of hundreds of borings, or other preconstructioninvestigative material mentions methane gas. A report of generalized soilconditions in the project area included reference to 80 soil borings; nonereported a possibility of methane. Of about 300 test borings in the last 8 or10 years in the Green Bay area, none produced methane gas. (T 40?50, 52?64,74?82). Respondent has constructed approximately 70 miles of tunnel in theMilwaukee, Wisconsin area, with one job in Madison, Wisconsin; most of theMilwaukee jobs followed water courses and it was not uncommon to encountertraces of organic materials (which may produce or release flammable gas); thebiggest gas problem has been carbon dioxide. In 21 years with respondent, Mr.Peterson has never encountered methane gas, and has never heard of anyone elsereporting this gas in Wisconsin tunnel projects (T 663, 665?671). Beforebidding the job, respondent took customary steps necessary to understand theproject, including consideration of reports and tests of underground content,soils and formations (T 675?681, 686?689, C?2, C?3, C?4, C?4a, C?5, C?6, C?7).Prior to May 12 there had been extensive subsurface construction by othercontractors within the immediate area (T 697). In addition, respondent hadcompleted approximately 4,000 feet of tunnel as a subcontractor for others (T691?693), plus 1,2001gfeet of the subject tunnel (R?1). No contractor or consulting engineer hadencountered methane gas or had suggested its possibility.??????????? Respondentcould not reasonably have expected to encounter methane gas, but thiscircumstance does not serve to suspend the application of the cited standard.Methane gas is not specifically stated in the standard but it is not excluded.There is no occupational safety and health standard specifically and solelyapplicable to a subsurface tunnel environment during depressurization. However,the cited standard applies continuously during tunnel construction. It does notrequire continuous quantitative testing, unless the circumstances of the tunnelenvironment deem it advisable. The events and observations during the 12 hourperiod before the explosion made necessary the conducting of quantitativetesting by appropriate instruments to assure that the required quality andquantity of air was maintained. This was not done and a violation resulted. Theviolation was serious within the meaning of the Act.4??????????? Complainant?srequirement of immediate abatement is confirmed. Respondent has been engaged inthe construction of open-cut and underground sewers for approximately 40 years.This employer has received a substantially better than average industrialrating for workmen?s compensation premium purposes from the Wisconsin RatingBureau, effecting a saving to the Green Bay owner of almost $40,000, since theworkmen?s compensation rate was a bid item. This is indicative of a generallysatisfactory safety record and program. However, considering the gravity of theviolation, a penalty of $800 is assessed.20 CFR 1926.800(c)(2)(i)(v):??????????? ByMay 12, 1975 the tunnel construction had progressed to 6001g feetaway from the shaft (T 126). For about one hour immediately before theexplosion the tunnel was not functioning under a compressed air environment andduring that interval, air was supplied to the tunnel employees through two 3\/4inch high air line hoses, one of which extended to about 25 feet from themining machine and a greater distance from the face of the tunnel (T 127, 409,410, 597). This high air was produced by a compressor with a rated capacity of125 psi. The manifold valve controlling the air flow through the hose wasopened from one-fourth to one-half of full capacity (T 597). The maximumquantity of air entering the tunnel was 184.6 cubic feet per minute per hose?(C?18)5. Six employees were in the tunnel atthe time of explosion (T 566).??????????? Thehigh air hoses were in the tunnel to provide power to pneumatic drills. When arock was encountered, a 1?1\/4 inch hole was drilled, generally to a depth of 12to 21 inches, with the greater number around 15 inches. A small explosive wasused. There were 70 drilling and blasting entries between February 17 and April29, 1975; the next entry was September 3 (C?9). This activity representedblasting and\/or rock drilling within the meaning of the cited standard.Respondent contends that air tools were not being used near the face and thatthe hoses were used primarily to get air into the front (T 217, 218). However,the hoses did not add air to the tunnel sufficient to meet the required minimumof not less than 200 cubic feet per minute for each employee underground.Whatever the linear velocity of the air flow in the tunnel bore may have been,it was substantially less than 30 feet per minute. The high air hoses did notprovide mechanically induced primary ventilation in all work areas in thetunnel. The direction of air flow, if any, was not reversible.??????????? Theair coming out of the hoses had no overall ventilating effect. It caused someair movement but probably fell off after a few feet (T 396, 421, 430, 431). Inthe absence of suitable purifying devices on the compressor, the air comingthrough the high air line hoses was not fresh air6 (T 433,434, 435). Fresh air is not necessarily ?pure? air, whatever that might be.?Fresh air? within the meaning of the cited standard means air sufficient inquality to sustain human life.??????????? Therewas no adequate ventilating system. No fan was in use. A fresh air tunnel, asdistinguished from a compressed air tunnel, normally is ventilated by use ofabove-ground fans connected to duct work, extending vertically down a shaft orbore hole and turning at angle to extend to the working face. The fan should bereversible to either exhaust toxic flammable gases from the face, or to blowfresh air directly to the working chambers (T 378).??????????? Respondentfailed to comply with the cited standard. The violation is serious within themeaning of the Act4a.Immediate abatement was reasonable. Fans and a duct system could have beeninstalled. Respondent was planning to install a ventilating system; a vent ordown hole had been dropped near the face area and fans were on the site but notinstalled (T 117, R?1:10.01). Respondent believes the tunnel would notaccommodate a 24 inch duct, considering the numerous temporary installations inthe tunnel7,including car tracks; also, such ventilating system would impede employee movementin the tunnel and make rapid egress difficult. A proper ventilation system,however, would have provided the exposed employees to reasonably safe andhealthful working conditions, as contrasted to the tunnel environmentprevailing on and about May 12, 1975.?Based upon the gravity of the violation, a penalty of$800 is assessed.FINDINGS OF FACT??????????? 1. W.J. Lazynski, Inc., respondent, is a corporation with an office and place ofbusiness at 4445 North 124th Street, Milwaukee, Wisconsin, and is engaged insubsurface construction and related activities.??????????? 2. OnMay 12, 1975 respondent had a workplace at the Fox River Tunnel, 1496 BylsbyAvenue, Green Bay, Wisconsin, where it was engaged in the construction of asanitary district sewer tunnel under contract for the Green Bay MetropolitanSanitary District.??????????? 3.Respondent commenced work activities for the Fox River Tunnel on or about May6, 1974 by excavating a shaft of 24 foot diameter and 100 foot depth and onFebruary 17, 1975 began horizontal construction of the tunnel.??????????? 4.There were three work shifts, each having from six to eighteen employees.??????????? 5. OnApril 9, 1975 respondent changed the tunnel atmosphere from free air to achamber pressurized at about 12 psi.??????????? 6.Tunnel construction continued under the pressurized air system at about 12 psiuntil May 10, 1975.??????????? 7.Respondent began to depressurize the tunnel on May 10, 1975 and completeddepressurization at approximately 6:00 a.m. on May 12, 1975.??????????? 8. Atabout 7:00 a.m., six of respondent?s eight first shift employees entered thetunnel.??????????? 9. OnMay 12, 1975 and prior thereto respondent had instruments at the work site totest the atmosphere quantitatively for carbon monoxide, nitrogen dioxide,flammable or toxic gases, dusts, mists and fumes that might occur in the tunnelor shaft. During the period from about 7:00 p.m. on May 11, 1975 until about7:00 a.m. on May 12, 1975, respondent failed to require the use of suchinstruments in the tunnel to test the atmosphere quantitatively.??????????? 10.During the period set forth in Finding of Fact 9, no tests were conducted toassure that the required quality and quantity of air was maintained.??????????? 11.Test records were destroyed on May 12, 1975.??????????? 12.On May 12, 1975 and prior thereto miner?s safety lamps were used in the tunnelto check the atmosphere. The miner?s safety lamp is not an instrument capableof testing the tunnel atmosphere quantitatively.??????????? 13.On May 12, 1975 the sole source of air provided respondent?s employees, otherthan the air existing in the tunnel, was by means of two 3\/4 inch high airhoses, with compression provided by a 900 CFM Ingersoll-Rand portable high aircompressor with a rated capacity of 125 psi.??????????? 14.The high air hoses were in the tunnel primarily for operation of power toolsbut were used by respondent on May 12, 1975 as a temporary means ofventilation.??????????? 15.The maximum quantity of air entering the tunnel through each high air hose, setforth in Findings of Fact 13 and 14, was 184.6 cubic feet per minute.??????????? 16.The 3\/4 inch high airline system was incapable of reversing the direction ofairflow.??????????? 17.On May 12, 1975 the supply of additional air to the tunnel was less than 200cubic feet per minute for each employee underground.??????????? 18.Blasting or rock drilling operations were conducted in the tunnel until April29, 1975 and resumed September 3, 1975.??????????? 19.The linear velocity of the airflow in the tunnel bore was less than 30 feet perminute on May 12, 1975.??????????? 20.At about 7:00 a.m. on May 12, 1975 after first-shift employees entered thetunnel, an explosion occurred within the tunnel, killing four employees andinjuring others.??????????? 21.Following the explosion, methane gas was found in the tunnel in harmfulquantities.CONCLUSIONS OF LAW??????????? 1.The Review Commission has jurisdiction of the parties and of the subject matterherein.??????????? 2. OnMay 12, 1975 respondent failed to comply with occupational safety and healthstandard 29 CFR 1926.800(c)(1)(i) as required by section 654(5)(a)(2) of theAct.??????????? 3. OnMay 12, 1975 respondent failed to comply with occupational safety and healthstandard 29 CFR 1926.800(c)(2)(i)(v) as required by section 654(5)(a)(2) of theAct.ORDER??????????? It istherefore ORDERED that the above citations be and the same are hereby affirmed.Penalty is assessed in the sum of $1,600.?George W. OttoJudge, OSHRCDated: July 15, 1976\u00a0[1] 29 U.S.C. ??651?678, hereinafter ?the Act.?[2] The standard at29 C.F.R. ? 1926.800(c)(1)(i) provides:?1926.800 Funnels and shafts.(c)Air Quality and Ventilation.(1)Air quality and quantity.(i)Instruments shall be provided to test the atmosphere quantitatively for carbonmonoxide, nitrogen dioxide, flammable or toxic gases, dusts, mists, and fumesthat occur in the tunnel or shaft. Tests shall be conducted as frequently asnecessary to assure that the required quality and quantity of air ismaintained. A record of all tests shall be maintained and be kept available.[3] This process canbe defined as the decomposition of organic material by microorganisms andbiochemical processes in the absence of oxygen.[4] These were thesame borings that were examined by the Secretary?s witnesses.[5] Peterson statedthat in his twenty-one years of mining experience in Wisconsin, he had neverencountered methane. In addition, there was no record of any previous explosionin Wisconsin history related to methane gas.[6] Some of thequantitative testing devices present included: Universal Testing Units fornitrogen dioxide; an MSA oxygen analyzer or cyl which was used in conjunctionwith a miner?s safety lamp to test the oxygen in the tunnel, and a generalcombustible gas indicator or explosimeter.[7] Lazynskipresented no evidence that it conducted quantitative tests duringdecompression. However, one of the Secretary?s compliance officers, who hadinvestigated the accident, testified that Lazynski?s second shift foreman,Anderson, told the compliance officer that He had conducted quantitative testsat 7:00 p.m. on May 11, 1975, the evening before the accident, but had notlogged in the results of those tests, as he normally did. Based on thisevidence, Judge Otto found that Lazynski had conducted quantitative tests at7:00 p.m. on May 11, and for that reason he limited his finding of a violationto the period between 7:00 on May 11 and the explosion on May 12.We do not accept the judge?sfinding that Lazynski conducted quantitative tests at 7:00 on May 11. Althoughwe have no reason to doubt that the compliance officer accurately reported whatAnderson told him, Anderson?s statement, coming during the investigation of a tragicaccident, would tend to exculpate Anderson from any fault in the accident, andmust be regarded as inherently suspect for that reason. Further doubt is castby Anderson?s failure to follow the normal practice of logging in the resultsof the purported tests. Moreover, Anderson was not called to testify, so therewas no opportunity for either party to question him on the truth of hisstatement.If Lazynski had in fact conductedquantitative tests on the evening of May 11, we would expect Lazyaski to relyon such evidence as an indication that it had in fact complied with thestandard. Instead, Lazynski has not contended that it conducted quantitativetests during compression or decompression, but, to the contrary, has contendedthat at least during compression, quantitative tests could not be conducted.This sheds further doubt on the accuracy of Anderson?s statement.We do not reject Anderson?sstatement simply because of its hearsay nature. Hearsay is admissible in ourproceedings and may be used as probative evidence. Hurlock Roofing Co., OSHRCDocket No. 14907 (October 31, 1979). In this case, however, Anderson?sstatement is inconsistent with other evidence and the circumstances under whichit was made cast serious doubt on its reliability. Standing alone, hisstatement is insufficient evidence on which to base a finding that Lazynskiconducted quantitative tests on the evening of May 11.[8] At 6:15 a.m. onMay 12, the lamp flickered somewhat. However, the employees attributed itsinconsistency to either a draft in the tunnel or the result of going off ofcompressed air. Compliance Officer Randall Sherman testified that Zalewski toldhim the air in the tunnel had been ?bad? or ?dead? all night and that ?it gotworse toward morning.? As they were leaving the tunnel at the end of the thirdshift, one of the lamps went out. However, the men assumed that this was due toa lack of fuel.[9] The citationspecified that quantitative instruments were ?not utilized as required on orbefore May 12, 1975.?[10] Other standardsin the same subsection expand on this requirement. Thus, ? 1926.800(c)(1)(iv)prohibits the exposure of employees to airborne contaminants in excess of thelimits established in the 1970 edition of ?Threshold Limit Values of AirborneContaminants,? as adopted by the American Conference of Government IndustrialHygienists. Subsection 1926.800(c)(2)(vi) requires that employees be withdrawnfrom an underground location from which the air returning through theventilation system contains a concentration of 1.5 percent or higher offlammable gas, and prohibits their return until the concentration of such gasis reduced to 1 percent or less.[11] See also GeneralDynamics Corp., Quincy Shipbuilding Div. v. OSHRC, 599 F.2d 453, 464 (1stCir. 1979).[12] We need nottherefore address Lazynski?s argument that the failure of Brenton and Zalewskito report their observations constituted unpreventable employee misconduct.[13] See C.Kaufman, Inc., 78 OSAHRC 3\/C1, 6 BNA OSHC 1295, 1977?78 CCH OSHD?\u00a022,481, (No. 14249, 1978).[14] Because therecord is unclear as to the exact point during decompression that quantitativedevices could again be used, we cannot determine the frequency with which areasonable person would have conducted quantitative tests during decompression,and therefore do not find a violation based on Lazynski?s failure to testduring decompression.[15] The standards at29 C.F.R. ?? 800(c)(2)(i) and (v) provide:(2)Ventilation.(i)Tunnels shall be provided with mechanically induced primary ventilation in allwork areas. The direction of airflow shall be reversible.(v)The supply of fresh air shall not be less than 200 cubic feet per minute foreach employee underground. The linear velocity of air flow in the tunnel boreshall not be less than 30 feet per minute in those tunnels where blasting orrock drilling is conducted or where there are other conditions that are likelyto produce dusts, fumes, vapors, or gases in harmful quantities.[16] 29 C.F.R. ?1926.804(e) contains the following definition:(e)?High air??Air pressure used to supply power to pneumatic tools and devices.[17] Pipe jack mining,a relatively new concept in tunnel mining, is accomplished by pushing concretepipes into the shaft by hydraulic jacks.[18] The standard at29 C.F.R. ? 1926.803(i)(1) provides in pertinent parts:(i)Ventilation and air quality(1). . . Ventilating air shall be not less than 30 cubic feet per minute.[19] Lazynski keeps apneumatic drill in its tunnel which is powered by the two high air lines. Whenthe company encounters a boulder that is too cumbersome for its mining machineto handle, it drills a small hole in the rock and places a ? pound charge init. Between February 17 and April 29, 1975, several drilling and blastingentries took place. After the May 12 methane explosion, blasting did not resumeuntil September 3, 1975.[20] The standardspeaks of a supply of ?fresh air,? and there is evidence in the recordindicating that high air may contain impurities. There is also evidence that itis, or may be, possible to filter out these impurities. Inasmuch as Lazynskiwas not cited for failing to provide ?fresh? air, we need not decide whetherfiltered high air would qualify as ?fresh air? under the standard.[21] The argument thatthe tunnel was ?full of air? following decompression is also inconsistent withthe testimony of Lazynski?s president, who stated that ?in numerous jobs,numerous times, we have run into a condition where we have had an oxygendeficiency in the tunnel.? The witness explained that the oxygen deficiencywould arise from carbon dioxide replacing the oxygen in the air. He furtherstated that they had to be alert for oxygen deficiency during decompression,when carbon dioxide from the soil could enter the tunnel atmosphere. Thistestimony indicates that an adequate supply of fresh air from an externalsource is particularly important following decompression.[22] The statedmeasurement, dimension or time is approximate.1a See fn.1.1b See fn.1.1c See fn.1.1d See fn. 1.1e See fn.1.1f See fn.1.2 devoid of air. 3 29 CFR 1926.804 contains the followingdefinitions:(e)?high air??air pressure used to supply power to pneumatic tools and devices.(f)?low air??air supplied to pressurize working chambers and locks.1g See fn.1.4 29 U.S.C. ? 666(j).1g See fn.1.5 C-18:Maximumamount of air possible to pass through a 3\/8 inch orifice (1\/2 of 3)???????? 284 CFMAdjustmentfactor for sharp-edged orifice????????????????????????????????????????????????????? .65Maximumamount, net?????????????????????????????????????????????????????????????????????????????????? 184.6CFM\u00a06 Complainant has supplied adictionary definition of ?fresh air? as ?uncontaminated outdoor air.?? It appears likely that as so defined, freshair is nonexistent.4a See fn.4.7 The tunnel was excavated to102 inches, with a finished diameter of 72 inches.”