KANSAS CITY POWER & LIGHT COMPANY, a corporation

OSHRC Docket No. 76-5255

Occupational Safety and Health Review Commission

March 15, 1982

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Before: ROWLAND, Chairman; CLEARY and COTTINE, Commissioners.  

COUNSEL:

Office of the Solicitor, USDOL

T. A. Housh, Jr., Regional Solicitor, U.S. Department of Labor

Pat Shannon and Lynn M. Snelgrove, Kansas City Power & Light Company, for the employer

OPINION:

DECISION

BY THE COMMISSION:

A decision of Administrative Law Judge Alan M. Weinman is before the Commission under section 12(j), 29 U.S.C. §   661(i), of the Occupational Safety and Health Act of 1970, 29 U.S.C. § §   651-678 ("the Act").   In his decision, Judge Weinman vacated a citation alleging that Respondent, Kansas City Power & Light Company, committed a serious violation of the "general duty clause," section 5(a)(1) of the Act, 29 U.S.C. §   654(a)(1). n1 In response, the Secretary of Labor ("the Secretary") filed a petition for discretionary review.   Commissioner Cleary then directed review of all of the issues raised by the Secretary's petition, including the principal issue of whether the judge erred in concluding that the Secretary failed to establish that the cited conditions constituted a "recognized hazard" within the meaning of section 5(a)(1).   For the reasons that follow, we reverse the judge's decision that he Secretary failed [*2]   to sustain this burden of proof and remand the case for further proceedings.

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n1 Section 5(a)(1) of the Act provides that "[e]ach employer . . . shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees."

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I

Respondent generates and sells electricity in Kansas City, Missouri.   On October 19, 1976, an explosion in the "F" coal pulverizer area of boiler unit 5 at Respondent's Hawthorn Road power plant injured 15 employees.   Occupational Safety and Health Administration ("OSHA") compliance officer Garvin Pyron investigated the accident on October 19 through 22, 1976.   Consequently, the Secretary issued to Respondent a citation alleging a serious violation of the Act for failure to comply with section 5(a)(1) in that:

the employer did install, or permit to be installed, tripping devices in the control circuits of the unit number 5 coal pulverizers in such a manner that it is   [*3]   possible for a failure of a raw fuel (coal) feeder to cause both a pulverizer and its associated exhaust to stop instantaneously without purging and while charged with heated partially pulverized coal, thereby increasing the chance of explosion.

To produce electricity at the cited facility, Respondent burns coal in a massive boiler to convert water to steam that is used to generate electricity.   The process begins when raw coal is fed by six feeder belts to six pulverizers, where the raw coal is simultaneously heated at 600 to 800 degrees Fahrenheit and ground by rollers to a fine powder.   Exhausters attached to each pulverizer carry the powdered coal to the boiler. The coal dust is then injected into the four corners of the boiler at six different levels in a tangential firing process.   Control room operators monitor the feeders, the pulverizers, and the boiler with a computer, sensing instruments, and electrical circuits designed to sustain or stop operation under particular conditions.

In this operation, Respondent uses electrical circuitry designed and installed by Combustion Engineering, Inc.   One feature of the circuitry, referred to at the hearing as the "adjacent mill trip,"   [*4]   electrically interconnects each coal pulverizer and its feeder belt with the feeders that supply adjacent pulverizers. As a result of this interconnection, the adjacent mill trip will stop a loaded pulverizer abruptly under certain conditions without purging or exhausting the pulverizer of coal or volatiles.   For example, if the feeder belt for F pulverizer trips or stops, the F pulverizer will stop automatically after a 3-second delay if the feeder belt for the adjacent E pulverizer drops to less than 50 percent of its operating speed. Moreover, when the F pulverizer stops under these circumstances, its exhauster also stops, thereby leaving any residual accumulations of partially pulverized coal dust confined within the pulverizer. Compliance officer Pyron, a former control operator at a coal-fired power plant, n2 surmised that this sequence of events preceded the explosion at issue.   In addition, a joint management-labor investigating committee concluded that the adjacent mill trip interlock caused the explosion.

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n2 Pyron had worked with the Tennessee Valley Authority ("TVA") as a control room operator at coal-fired generating plants for 12 years, from 1957 until 1969.   In addition, Pyron testified that he had experience with Combustion Engineering systems, including the type of pulverizers used by Respondent.   However, he admitted he had no operator experience since 1969 and he had no mill circuitry design experience.   Pyron also noted that he first heard about adjacent mill trip circuitry only during his investigation.

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Witnesses for both parties indicated that coal accumulations in pulverizers are subject to spontaneous combustion and explosion. For example, Pyron emphasized that pulverized coal is "at the very best dangerous," and that, even "under the very best of conditions and the closest control," there will be explosions.

Nevertheless, according to Pyron, the circuitry used by Respondent exacerbates the explosion hazard inherent in pulverizer shutdowns because the 3-second delay in the pulverizer trip does not allow sufficient time to exhaust coal dust and gases that accumulate in the pulverizer. Pyron stressed that a pulverizer should not be stopped if "there is any possibility of coal dust or volatile[s] remaining in it until it has been cooled down except in the most extreme circumstances." n3 Other control room operators who testified on behalf of the Secretary agreed that failing to exhaust a pulverizer before an automatic trip is a dangerous practice.

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n3 Before the hearing, the Secretary stipulated that instantaneous pulverizer trips are appropriate under the following conditions: (1) boiler trips, (2) loss of unit DC power, (3) manual operator control trips, (4) electrical faults in pulverizer drive motors, (5) loss of AC power, and (6) exhauster discharge gate closed.   However, in the Secretary's view, tripping a pulverizer under what he deems to be normal conditions, solely based on a reduction in adjacent feeder speed, is unnecessarily hazardous.

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The Secretary also submitted evidence, in the form of a list supplied by Respondent, that from March 11, 1971, to March 23, 1977, 19 coal pulverizer explosions at Hawthorn unit 5 had caused external damage.   According to this evidence five of these explosions occurred after the incident in question.   Although the record does not indicate the cause of these pulverizer explosions, Herbert C. Temme, Respondent's consulting engineer, admitted that the list "indicates more explosions than we would like and maybe than we should expect."

Pyron suggested that Respondent could abate the hazard by removing the adjacent mill trip or by installing a time delay to assure purging of the pulverizers before stopping. In addition, after the explosion at issue, the investigating committee of management and employee representatives recommended removal of the adjacent mill trip. According to Norbert Kurle, a control operator for Respondent and a member of the investigating committee, although management officials had agreed to follow this recommendation, Respondent did not remove the trip.

Respondent's engineering witnesses,   [*7]   Temme and Richard E. Drake II of Combustion Engineering, both opposed removal of the adjacent mill trip on the ground that its purpose was to increase safety by reducing the hazard of boiler explosions. They urged that the interlock is designed to prevent accumulations of coal dust in a boiler that may lack "ignition energy" or flame to consume the coal. Such accumulations of powdered coal exhausted from a tripped pulverizer could lead to a boiler explosion, according to both Temme and Drake.   Furthermore, Drake stressed that the Combustion Engineering equipment used by Respondent is specifically designed to comply with the National Fire Protection Association ("NFPA") provision at chapter 85-E, section 583, that in effect prohibits injection of coal into a boiler without flame.

Temme testified that Respondent normally exhausts and cools coal pulverlizers as part of its shut down procedure.   However, when activated by the tripping of one feeder and the reduced speed of an adjacent feeder, the adjacent mill trip will automatically stop a pulverizer to prevent injection of coal from that pulverizer into a boiler that may lack sufficient flame to consume the fuel, according to Temme.   [*8]  

The Secretary's witnesses disagreed with Temme's view that adjacent mill tripping is necessary because feeder speed somehow "proves" boiler ignition. Instead, they testified that feeder speed does not indicate the lack of boiler ignition or unstable flame and therefore does not warrant an instantaneous trip of a pulverizer and the concomitant risk of a pulverizer explosion. In addition, several operators testified that allowing a pulverizer with a failed feeder to operate until its coal is exhausted into the boiler does not endanger the pulverizer or the boiler. Furthermore, according to operator testimony, other instruments, aside from the feeder trip, are available to show boiler ignition. In addition, there was disagreement among the witnesses as to which alleged hazard, boiler explosions or pulverizer explosions, presented the greater danger to employees.

The Secretary's witnesses also indicated that the questioned circuitry interlock is not commonly used in the utility industry.   Compliance officer Pyron, who had 12 years of experience with the TVA as a control operator, testified generally that tripping a loadded pulverizer is not a common industry practice.   William Green,   [*9]   with 26 years of TVA experience, explained that TVA practice is to allow a pulverizer to run until it is exhausted once a feeder trips. Plants under his control had never had a pulverizer explosion when the pulverizer was shut down that way.   Earl Wayne Downs, a plant supervisor for South Mississippi Electric Power Association and a former test engineer with TVA experience, testified that, in every location where he had worked, a pulverizer had to be completely empty before it was shut off.   For example, Downs explained that the South Mississippi facility uses an interlock that is the opposite of Respondent's circuitry because it is designed to assure that the pulverizer is cleared of charged material before it shuts down.   Specifically, the circuitry prevents the pulverizer from being tripped manually for five minutes after its feeder stops.   Downs saw no reason for an immediate trip on the pulverizer here within 3 seconds after the feeder stops because, he suggested, exhausting the coal and volatiles from a pulverizer causes no damage to the pulverizer or the boiler. In view of the pulverizer explosion danger, Downs testified that he would not want adjacent mill tripping "in my [*10]   plant." In addition, both Pyron and Green had operated Combustion Engineering equipment that did not use an adjacent mill trip.

According to Respondent's consultant Temme, however, tripping a pulverizer without purging when a boiler lacks ignition is a common industry practice.   Temme named several companies that use an interlock like the adjacent mill trip. In addition, Drake testified that adjacent mill tripping is common to the Combustion Engineering system.   Drake also said that Combustion Engineering had installed 250 systems with adjacent mill trips, 150 of which were for coal-fired units.   Emphasizing a trend toward automation and away from operator control, Drake testified that the circuitry interlocks are used increasingly "to assist the operator so that he does not have to have the choice of making an incorrect decision." Drake also testified that the TVA had requested that Combustion Engineering submit a proposal for adjacent mill circuitry at a plant where two boiler explosions had occurred within a year.

In his post-hearing brief, the Secretary contended that stopping a pulverizer without exhausting coal and volatiles is a recognized hazard. The Secretary specifically [*11]   argued that NFPA Code provisions indicate that the utility industry "for years had recognized the hazards of residual coal charges in pulverizers." In his brief, the Secretary cited NFPA sections on coal-fired boilers and pulverized fuel systems that warn of an explosion danger from heated, pulverized coal accumulations and also detail purging procedures.   On the explosion hazard, the Secretary cited section 564, chapter 85-E, of the 1974 NFPA Code, which provides in pertinent part that:

Pulverizers will, on tripping, have a residual charge distributed primarily in the pulverizer, but also in burner piping and nozzles.   This accumulation in a hot pulverizer will generate volatiles that are combustible and explosive.

In addition, this hazard is also mentioned in section 4214, chapter 60, of the 1975 NFPA Code:

Pulverizers tripped under load will have fuel remaining in the hot pulverizer, burner piping, and burners. These accumulations may cause spontaneous ignition of the fuel or an explosion.

Furthermore, the Secretary argued that purging of pulverizers is specifically required by sections 624 and 6243, chapter 60, 1975 NFPA Code, which provide:

624.   Clearing Procedures For   [*12]    Pulverizers Tripped Charged With Fuel. In order to minimize hazards caused by accumulations within the pulverized fuel system equipment, as discussed in section 616 [dealing with accumulations at the time of initial start up], the following procedure shall be used to clear fuel from the system as soon as possible after it has been tripped while containing a charge of fuel.

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6243.   Continue to operate the pulverizers until empty and in normal condition for shutdown.

Finally, the Secretary emphasized that the NFPA Code contains no provision that approves or provides for either adjacent mill tripping or, except under emergency conditions, stopping a loaded pulverizer without exhausting.

II

Judge Weinman vacated the citation based on his conclusion that the Secretary failed to prove that Respondent's pulverizer control circuitry was a "recognized hazard" under section 5(a)(1) of the Act.   In reaching this conclusion, the judge refused to consider the NFPA provisions advanced by the Secretary to support the citation because they were "advisory provisions of newly promulgated national consensus standards." The judge in effect reasoned that it would be inequitable to base a 5(a)(1)   [*13]   charge on the NFPA provisions when Respondent would have been exempt under a "grandfather clause" if the NFPA provisions had been adopted as OSHA standards.   However, the judge noted that "[a]dmittedly, Respondent made no effort to clear the pulverizer as recommended [in the NFPA Code]." The judge also found that the engineering testimony of Respondent's witnesses on "other coal-fired generating plants that incorporate adjacent mill tripping in their circuitry" rebutted the Secretary's evidence on industry practice.   The judge specifically relied on Drake's testimony that adjacent mill tripping is common to the Combustion Engineering system.   He concluded that "neither the collective force of their [the Secretary's witnesses'] opinions nor the history of explosions and injuries . . . is sufficient to establish the existence of a recognized hazard on October 19, 1976, in the face of unrebutted testimony that the disputed circuitry logic was commonly used in the industry."

The Secretary maintains that he established a recognized hazard based on both industry recognition and employer knowledge of an explosion hazard created by tripping a loaded pulverizer.

According to the Secretary,   [*14]   industry recognition is established by the testimony of the compliance officer and operators that (1) a loaded pulverizer should be tripped only in extreme situations and, even then, only if purged, and (2) common TVA practice is to purge pulverizers before they are stopped.   The Secretary further maintains that the 1974 and 1975 provisions of the NFPA Code, noted in his post-hearing brief, address the cited hazard and provide "unequivocal evidence" that an industry safety authority recognizes the hazard.

Furthermore, the Secretary contends that Respondent actually knew of the cited hazard. The Secretary notes that Respondent normally purges pulverizers before stopping them to avoid explosions. This "work rule," according to the Secretary, manifests Respondent's understanding of the hazard of allowing coal to remain in an inert pulverizer. In addition, the Secretary charges that Respondent had constructive knowledge of the cited hazard based on (1) evidence of nineteen explosions to six years at the cited facility, (2) testimony that each pulverizer had exploded at some time, and (3) the admission of Respondent's engineering consultant that "there were more pulverizer explosions [*15]   than we would like." In the Secretary's view, its history at least provided Respondent with notice that its method of pulverizing coal was hazardous.

Respondent contends that the Secretary failed to sustain his burden of proving that the adjacent mill trip is a recognized hazard. Respondent agrees with the judge that the Secretary failed to prove that the use of the adjacent mill trip is against common industry practice.   In this connection, it charges that the operator testimony including the testimony of the compliance officer, is unrepresentative, unreliable and limited because, among other things, these opinions are out-of-date or irrelevant to Respondent's equipment.   In contrast, Respondent urges the "wide" experience of its engineering witnesses who explained the circuitry logic and the dangers of not using a trip. Furthermore, Respondent notes testimony on other facilities with similar circuitry interlocks and the industry trend toward plant automation.

Respondent also contends that the judge correctly refused to consider NFPA provisions as evidence of a recognized hazard. Respondent asserts that the Secretary may not rely on an advisory, nonretroactive industry standard [*16]   not adopted by OSHA to establish a recognized hazard under section 5(a)(1).   To decide otherwise violates due process, Respondent reasons, because an employer is entitled to "more notice, more particularity, and more specificity" if the Secretary seeks to prove a general duty clause violation. n4 Respondent specifically urges that the Secretary must show that the provisions he relies on are actually directed to prevention of the cited hazard. According to Respondent, the provisions here are too ambiguous and general to establish a hazard. Furthermore, if the Commission permits the Secretary to rely on NFPA "advisory" provisions, Respondent urges that it should be allowed to submit evidence on the inapplicability of those standards to the cited facility.   Finally, Respondent maintains that none of the Secretary's witnesses testified that it had violated any specific provisions.   Respondent specifically notes that it objected to the Secretary's cross-examination on NFPA Code provisions on the ground that the Code was inapplicable to the advanced circuitry at the cited facility.

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n4 Nevertheless, despite these assertions, Respondent concedes that "[i]ndustrial operating codes, if established to be widely accepted in the particular industry and applicable to the situation or condition in issue, can be indicative of commonly accepted safety standards." Indeed, it further notes that the parties "have agreed that the National Fire Protection Association Pulverized Fuel Systems Code sets generally recognized industrial guidelines for the area of pulverized fuel systems."

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Respondent also denies actual knowledge that its adjacent mill trip was a recognized hazard. Respondent urges that the Secretary "failed to present any credible proof that any explosion, including the one on October 19, 1976, was caused by the adjacent mill trip device. . ." It argues that evidence of past explosions is irrelevant because the Secretary failed to show that the earlier explosions were caused by the trip. In addition, Respondent notes that, before the explosion at issue, no request or recommendation was made to remove the trip.

III

To establish a section 5(a)(1) violation, the Secretary must show, among other things, that the cited employer failed to render its workplace free of a "recognized hazard." A recognized hazard is a condition or practice in a workplace that is known to be hazardous by either the industry in general or the employer in particular.   See, e.g., Beaird-Poulan, A Division of Emerson Electric Co., 79 OSAHRC 21/D11, 7 BNA OSHC 1225, 1979 CCH OSHD P23,493 (No. 12600, 1979).   The hazard, not the specific incident resulting in injury, is the relevant [*18]   consideration in determining the existence of a recognized hazard. See Brennan v. OSHRC (Vy Lactos Laboratories, Inc.), 494 F.2d 460 (8th Cir. 1974); Boeing Co., Wichita Division, 77 OSAHRC 188/D13, 5 BNA OSHC 2014, 1977-78 CCH OSHD P22,266 (No. 12879, 1977).   Moreover, the recognition element of an employer's duty under the general duty clause refers to knowledge of the hazard, not recognition of the means of abatement. General Dynamics Corp., Quincy Shipbuilding Division v. OSHRC, 599 F.2d 453 (1st Cir. 1979). Required abatement is determined by feasibility and an abatement order may prescribe practices of a higher standard than those an industry presently considers to be reasonable.   E.g., Williams Enterprises, Inc., 79 OSAHRC 24/A2, 7 BNA OSHC 1247, 1979 CCH OSHD P23,478 (No. 4533, 1979), aff'd, No. 79-1559 (D.C. Cir. June 9, 1980).

Applying these principles to the case before us, we conclude that the hazard was defined too narrowly when it was formulated in terms of whether use of the adjacent mill trip mechanism was recognized as a hazard. Indeed, both the judge and Respondent improperly define the hazard at issue in terms of the asserted cause [*19]   of the specific incident that led to injury and/or the suggested method of abatement, i.e., in terms of the use or nonuse of the adjacent mill trip. We conclude that the hazard here is the danger of pulverizer explosions resulting from accumulations of heated, pulverized coal. Removal or alteration of the adjacent mill trip device to prevent such accumulations is the suggested means of materially reducing this hazard. See Beaird-Poulan, a Division of Emerson Electric Co., supra. Accordingly, the judge erred in deciding that a recognized hazard finding is precluded in this case by Respondent's evidence that the disputed dircuitry was "common" to Combustion Engineering equipment and to the utility industry.

Furthermore, we conclude that the judge erred in refusing to consider NFPA Code provisions as evidence of industry recognition of this explosion hazard. Indeed, the courts and the Commission have looked to industry standards in determining industry recognition of a hazard. E.g., Bethlehem Steel Corp. v. OSHRC & Marshall, 607 F.2d 871 (3d Cir. 1979) (Respondent's safety officer admitted that advisory ANSI standard represented industry consensus); Titanium   [*20]    Metals Corp. of America v. Usery, 579 F.2d 536 (9th Cir. 1978) (recognition established by NFPA standard that Respondent helped draft); Betten Processing Corp., 75 OSAHRC 43/E2, 2 BNA OSHC 1724, 1974-75 CCH OSHD P19,481 (No. 2648, 1978) (judge erred in failing to consider ANSI standard as evidence of recognized hazard).   To the extent industry consensus standards reflect an industry's recognition of a hazard, they are relevant, probative evidence of a recognized hazard. n5 Consequently, the NFPA standards relied on by the Secretary are acceptable proof of industry recognition.   These provisions, as set forth above, caution that heated coal that is not exhausted from a pulverizer may explode and they recommend procedures for clearing loaded pulverizers to prevent such explosions. We conclude therefore that these industry standards establish industry recognition of an explosion hazard in pulverizers resulting from heated, pulverized coal accumulations. n6

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n5 The due process concerns of Respondent and the judge are based on a misconception of the role of advisory industry standards in section 5(a)(1) cases.   The Secretary does not seek in this case to use the NFPA provisions to define required or prohibited conduct under the general duty clause.   Instead, the Secretary properly submits the provisions as evidence of the utility industry's awareness or recognition of the hazard.

n6 We reject Respondent's argument that the NFPA Code does not apply to its facility.   Indeed, Respondent concedes that the Code applies generally to pulverized fuel systems and its engineering consultant admitted that the Code contains "a discussion of boilers in general and the order in which trips should work."

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In view of this evidence of industry recognition of the explosion hazard that allegedly existed at Respondent's worksite, we reverse the judge's conclusion that the Secretary failed to sustain his burden of proving the recognition element ("recognized hazard") of a section 5(a)(1) violation.   Because the judge made no findings or conclusions on the remaining elements of the alleged violation and because the record contains sharply conflicting testimony on certain elements, it is necessary to remand the case for further proceedings.

For these reasons, we reverse the judge's decision and remand the case to the judge for findings and conclusions on the remaining elements of the alleged section 5(a)(1) violation.

SO ORDERED.  

DISSENTBY: ROWLAND

DISSENT:

ROWLAND, Chairman, Dissenting:

I dissent from the majority's decision to remand this case for further proceedings on the elements of proof of a violation of 29 U.S.C. §   654(a)(1).   In my view, Judge Wienman properly held that the Secretary had failed to demonstrate the existence of a recognized hazard in Respondent's worksite. n7 However, while I would affirm the judge's decision [*22]   to vacate the citation, I do not fully agree with the judge's reasoning in support of his conclusion that a recognized hazard was not shown.   Specifically, I share the majority's view that the judge did not properly define the recognized hazard at issue in this case, but I would apply a different definition of the hazard than does the majority.   I also do not agree with the majority that the judge erred in his treatment of the National Fire Protection Association (NFPA) codes.

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n7 Since the existence of a recognized hazard is the first element of proof in establishing a violation of section 654(a)(1), it is unnecessary to consider the remaining elements, such as proof of feasible abatement methods, when, as here, the Secretary has not shown that the employer failed to keep its workplace free from a recognized hazard. BASF Wyandotte Corp., 81 OSAHRC    , 10 BNA OSHC 1250, 1982 CCH OSHD P25,831 (No. 78-2316, 1981).

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As explained in more detail below, the basic question in this case is whether Respondent is justified [*23]   in its belief that the inherent and unavoidable hazard of a pulverizer explosion is preferable to an explosion in the boiler or furnace which potentially can have far more serious consequences.   While no one disputes that it is desirable where possible to purge pulverizers prior to stopping them, this procedure cannot be adopted in certain limited situations where in Respondent's considered judgment it cannot be certain that a safe level of ignition exists in the furnace.

Before proceeding to the merits of this case, however, I must address a preliminary matter regarding the proper definition of the recognized hazard to be applied.

I.

As the majority correctly observes, the judge adopted an extremely narrow definition in that he required the Secretary to prove that Respondent's pulverizer trip circuitry mechanisms are understood as hazardous either by Respondent or by its industry.   The majority rejects this definition in favor of an extremely broad definition which characterizes the hazard in generic terms as the hazard of explosion caused by the accumulation of coal in a heated pulverizer. As the majority itself notes, however, the Secretary alleged in his citation and argues [*24]   in his brief yet a third formulation of the hazard -- an increased likelihood of explosion resulting from Respondent's practice, in certain situations, of allowing a pulverizer to stop before it has been exhausted of coal and volatile gases.   For the reasons that follow, I conclude that the definition presented by the Secretary is the appropriate formulation of the hazard in the circumstances of this case.

The requirement stated in 29 U.S.C. §   654(a)(1) that an employer provide employment and a place of employment "free from recognized hazards" imposes a broad obligation on the employer which is analogous to that imposed by the Secretary's standards regarding personal protective equipment, which also require the employer to protect against "hazards." In order to avoid the problem of fair notice inherent in such broadly-worded standards, it is well settled that they must be defined and limited by objective criteria sufficient to apprise an employer of his obligations.   E.g., Ryder Truck Lines v. Brennan, 497 F.2d 230 (5th Cir. 1974); Voegele Co., 79 OSAHRC 76/A2, 7 BNA OSHC 1713, 1979 CCH OSHD P23,860 (No. 76-2199, 1979), aff'd, 625 F.2d 1075 (3d Cir. 1980);   [*25]   Owens-Corning Fiberglas Corp., 79 OSAHRC 26/D6, 7 BNA OSHC 1291, 1979 CCH OSHD P23,509 (No. 76-4990, 1979), aff'd, 659 F.2d 1285 (5th Cir. 1981). Similarly, with respect to 29 U.S.C. §   654(a)(1) the court in National Realty & Construction Co. v. OSHRC, 489 F.2d 1257 (D.C. Cir. 1973) held that Congress intended to impose an "achievable" duty by which employers would be required to eliminate only those hazards which experts familiar with the industry would consider preventable.   See Frank Briscoe Co., 76 OSAHRC 129/A2, 4 BNA OSHC 1729, 1976-77 CCH OSHD P21,162 (No. 7792, 1976).

In my view, to afford an employer adequate notice of the scope of its obligation under section 654(a)(1) to keep the workplace "free from recognized hazards," the alleged hazard should be defined in terms of work practices or processes involved in the workplace in question over which the employer can reasonably be expected to exercise control.   Otherwise, it cannot be said that the hazard would be preventable in the ordinary course so as to render the employer's duty the achievable one intended by Congress.   While the degree of specificity required will depend upon the circumstances of each [*26]   individual case, here the majority's broad, generic definition of the hazard -- coal dust explosions in pulverizers -- does not direct Respondent's attention to a hazard which it could reasonably consider to be preventable.

In this case, it is obvious that pulverizers are understood both by Respondent and by the electric utility industry to present the hazard of explosion due to accumulated coal dust. Indeed, the provisions of the NFPA codes demonstrate that the hazard of an explosion caused by accumulated coal dust within a pulverizer is understood by the industry to be a normal incident of operations.   Nothing in the provisions cited by the majority gives any indication that such accumulations are not normally anticipated to occur or that explosions from such accumulations are not to be expected. n8

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n8 Although as the majority notes, Respondent's engineer Temme testified to the effect that the explosions which had previously occurred in the facility exceeded in frequency what he would "like" and "maybe should expect," this opinion was only tentative.   Temme was responding to a question from the judge as to whether in his judgment "that record [the prior explosions] indicate that there is either some design or operating problem with respect to the No. 5 unit?" He prefaced his answer with the explanation that the question was "probably unfair" because he had not "had a chance to evaluate the operation of that unit in detail." There is also evidence that none of the other explosions had resulted in any injury to employees.   The record, therefore, is not sufficient to establish that Temme was on notice from the occurrence of other explosions of any deficiency in Respondent's operating procedures, or in the design and construction of its facility, nor does it demonstrate that any employer in Respondent's industry would consider these prior incidents to be excessive either in frequency or severity.

Indeed, section 5311 of NFPA No. 60, the Standard for Installation and Operation of Pulverized Fuel Systems, emphasizes that pulverizers are designed with the expectation that explosions will occur: "All equipment of the pulverized fuel system which may contain pulverized fuel laden air . . . shall be designed . . . for containment of a possible internal explosion . . . ." This code also prescribes specific strength requirements for the construction of various parts of the pulverizer, but not including ductwork.   See section 53112.   The record shows that the explosion which resulted in the inspection in this case as well as the other explosions caused damage to ductwork but not to the pulverizers themselves.

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Accordingly, the majority's definition of the hazard as an explosion from accumulated coal dust within a heated pulverizer is inadequate under 29 U.S.C. §   654(a)(1), because Respondent would not regard the duty imposed upon it by this definition to be achievable.   Plainly, the reasonable employer in Respondent's industry would not consider the hazard of an explosion in a pulverizer to be preventable. n9

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n9 In a case analogous to this, the Second Circuit held that the Commission erred in defining the hazard presented by a facility used for the storage of both acids and cyanides as the formation of hydrogen cyanide (HCN), a lethal gas.   Pratt & Whitney Aircraft v. Secretary of Labor, 649 F.2d 96 (2d Cir. 1981). Noting that there is no dispute that uncontrolled formation of HCN at a place of employment would be recognized as a hazard, but further observing that no evidence showed that HCN had ever been formed at the employer's facility, the court held that the hazard could not properly be defined as uncontrolled formation of HCN, but rather "must have been a condition that might result in the generation of that lethal gas." Specifically, the court concluded that the Secretary was required to demonstrate that the manner in which Pratt & Whitney stored its chemicals was known as hazardous. The court found such proof based on the undisputed evidence that the industry generally stored acids and cyanides separately with separate drains so as to protect against the formation of HCN in storage areas.   649 F.2d at 101.

This case is distinguishable from Pratt & Whitney in that coal dust explosions do occur whereas in Pratt & Whitney the hazard alleged by the Secretary and found by the Commission -- formation of a lethal gas -- had not been known to have occurred previously in the employer's facility.   Nevertheless, Pratt & Whitney does stand for the proposition that the hazard must be defined in sufficiently specific terms to give the employer notice of its obligations under 29 U.S.C. §   654(a)(1).

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In this case as the majority notes the citation alleged, and the compliance officer testified to, a hazard predicated on a particular operating practice of Respondent -- that under certain conditions a heated pulverizer containing accumulated coal could be stopped without being purged.   Furthermore, the citation allegation, which is reiterated in the Secretary's complaint, makes it clear that the Secretary's concern is not the inherent possibility of explosion in pulverizer operations, but rather a hazard which would be considered preventable because it is created by a particular operating procedure.   I would accept the Secretary's definition of the hazard as sufficient to give Respondent notice of its duty in the circumstances of this case. n10

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n10 Although the majority acknowledges that the Secretary described the hazard - in both his brief before the judge and his brief before the Commission - in terms of stopping a pulverizer before it is purged, the majority states no reason for adopting a different formulation other than its belief that it is improper to define the recognized hazard in terms of the means of abatement sought by the Secretary.   The majority does not even give consideration to the Secretary's definition of the hazard despite the fact that the Secretary's definition is not addressed to a specific abatement method.   Although the citations and complaint refer to Respondent's tripping mechanisms, it is clear that the gravamen of the Secretary's charge is the failure to purge heated, charged pulverizers prior to stopping them.

Since I find the Secretary's formulation adequate, I need not consider at this time whether it is improper to define the hazard in terms of the specific abatement method.   Furthermore, since, as discussed infra, I would vacate for failure of the Secretary to prove his allegation, I need not now consider whether the majority is correct in its additional conclusion that in entering an abatement order for a violation of 29 U.S.C. §   654(a)(1) the Commission can require an employer to institute measures which exceed those presently understood as reasonable in the employer's industry.

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II.

As the majority properly observes, a hazard alleged to be recognized under 29 U.S.C. §   654(a)(1) must be known as hazardous by either the industry in general or the employer in particular.   In my view, the Secretary failed to establish that either Respondent or the industry as a whole recognize that it is hazardous to stop a heated, charged pulverizer under the conditions at issue in this case.

The Secretary presented the testimony of a number of employees as well as the compliance officer to the effect that pulverizers should not be stopped under such conditions.   However, neither the compliance officer nor the employee witnesses had any experience or training in the design or engineering of coal-fired boiler systems, and in particular in the design of pulverizer circuitry. As the majority notes, compliance officer Pyron also had no operator experience since 1969.   According to Drake, who had been employed for 12 years as a systems engineer for Combustion Engineering, the manufacturer of Respondent's boiler control system, the design of these systems has become far more sophisticated since the [*30]   1960's, consistent with a trend in the utility industry to automate the control operations as much as possible.   Drake specifically testified that Pyron had not worked at any facility having the type of burner control system which Combustion Engineering had installed at Respondent's plant. According to Drake, it is a basic principle of operation of coal-fired furnaces to insure that boilers contain a sufficient level of ignition to maintain combustion of the amount of fuel, in this instance coal, being introduced into the boiler. He indicated that this principle is embodied in the NFPA codes, n11 and he gave his opinion that discharging a pulverizer into the boiler without establishing an adequate level of ignition would not comply with the NFPA code.

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n11 He referred to section 573 of NFPA No. 85E, which is entitled "Standard for Prevention of Furnace Explosions in Pulverized Coal-Fired Multiple Burner Boiler-Furnaces." This section provides in pertinent part,

A Common emergency may arise due to a raw coal hangup or threatened unstable flame conditions due to wet coal or change in coal quality. . . .   If coal feed to an offending pulverizer subsystem can be restored or adequate ignition energy can be supplied before main burner ignition is lost, the subsystem may be continued in service provided the flame is stable.   However, if the main burner flame on any burner of any pulverizer subsystem is extinguished . . . then that burner or subsystem shall be shut down in a way that will prevent coal being reintroduced to the furnace in a random manner.

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Temme, Respondent's consulting engineer with 26 years experience in the design, construction, and operation of electric utilities, gave similar testimony.   In his view, it is essential to insure that the furnace has sufficient ignition energy to consume immediately the fuel being injected into it in order to avoid an explosion caused by accumulation of raw fuel. He considered a furnace explosion to have far more serious consequences than an explosion in a pulverizer. When asked whether, as the Secretary's witnesses contended, it is improper to shut down a pulverizer on the basis of a certain feeder speed before the pulverizer is purged of its fuel and volatile gases, Temme replied candidly that "there are real, honest differences of opinion on how best to handle the mill [pulverizer] under that circumstance." He expressed his opinion that "there is nothing wrong and probably very good judgment" to stop the pulverizer "when we get in a situation that we do not have ignition energy proved." He based this opinion on his belief and on his observations that when an operator is losing or has lost fuel output [*32]   from a pulverizer, the operator is more concerned with bringing other pulverizers on line to sustain ignition in the furnace than with the status of the pulverizer which has lost output, and consequently the operator may not have time to shut down that pulverizer through the normal purging procedure.   While acknowledging that other opinions may exist and that the recommended practices may vary among manufacturers, Temme concluded that the procedure he described, and which Respondent instituted, "is a commonly used technique."

In evaluating the weight to be given to opinion testimony, the Commission must consider a number of factors, including the knowledge and experience of the witness in the subject matter of his testimony and the reasoning with which his opinion is supported.   Air-Kare Corp., 81 OSAHRC    , 10 BNA OSHC 1146, 1981 CCH OSHD P25,758 (No. 77-1133, 1981) (dissenting opinion).   In this case, Respondent's witnesses are more qualified to testify with respect to the design of Respondent's facility and in particular with respect to the philosophy and logic on which the mill trip in question here is based.   Furthermore, both Temme and Drake specified in some detail the [*33]   basis for their opinions in terms of their observations and the factors which they indicated were taken into consideration in the circuitry design.   On the other hand, the opinions of the Secretary's employee witnesses were not based on any assessment of design philosophy, nor did the employees state any basis for their opinion other than their unsubstantiated belief that the speed of an adjacent feeder is not as reliable an indicator of the level of ignition in the furnace as is an operator's judgment.   Temme, who as indicated has greater familiarity with matters of design, testified without rebuttal that the control system incorporates a signal which indicates whether there is weight on the feeder belt and that the feeder cannot operate at a 50 percent speed unless it has a load on the belt.   On this basis, Temme stated that the correlation between a feeder speed of 50 percent or better and any actual coal feed of the same magnitude is "very high." This opinion was corroborated by Drake, who said that in Combustion Engineering's design the operation of an adjacent pulverizer feeder is a reliable indication of the level of ignition in the furnace. Accordingly, the Secretary has   [*34]   not shown by a preponderance of the evidence that Respondent had actual knowledge that under the circumstances presented in its operation a shutdown of a pulverizer prior to purge is hazardous. n12

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n12 The history of prior explosions does not show the contrary.   An unspecified number of these explosions had occurred while pulverizers were being purged in the manner advocated by the Secretary, that is, before the pulverizers were shut down.

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Nor does the record show that the industry as a whole recognizes that it is hazardous to stop a pulverizer prior to purging. At best, the testimony is conflicting regarding industry custom and practice.   Although Pyron possessed operating experience with other facilities using Combustion Engineering equipment which did not apply an immediate pulverizer trip, his operating experience was limited to a period of time prior to the fundamental change in the theory of boiler control circuitry design on which the shutdown without purge is based.   While witness Green did have current [*35]   operating (but not design) experience with Combustion Engineering equipment at TVA, his testimony regarding the practice in TVA facilities is not persuasive in view of Drake's unrebutted statement that in 1976 one TVA facility, Widow's Creek, requested that Combustion Engineering install a burner control system similar to that of Respondent's plant after two explosions in the furnace had occurred.   As the majority indicates, Combustion Engineering has installed 250 such control systems, most of which are used in coal-fired units.   The widespread use of control circuitry of the type installed in Respondent's facility represents at least some consensus in the industry that the circuitry design is capable of properly detecting an inadequate ignition level and that it is acceptable to stop a pulverizer prior to purging when an inadequate ignition level in the furnace does not exist.

Nor do the provisions of the NFPA standards require an opposite conclusion.   The cases cited by the majority support the proposition that proprietary standards of private organizations, such as the NFPA, are relevant but not dispositive on the question of industry recognition.   For example, in Bethlehem   [*36]    Steel Corp. v. OSHRC, 607 F.2d 871 (3d Cir. 1979), the court noted both the employer's concession that the standard represented an industry consensus and the compliance officer's testimony regarding the practices of other employers.   In Titanium Metals Corp. of America, v. Usery, 579 F.2d 536 (9th Cir. 1978) the totality of the evidence consisted of the employer's own experience, employee complaints, and adoption of a safety program as well as the provisions of the NFPA code.

Furthermore, in this case the NFPA provisions indicate that the industry as a whole does not regard Respondent's practice as hazardous. In particular, section 624 of NFPA No. 60, quoted in part in the majority opinion, on its face assumes that pulverizers will be tripped under a load condition in normal operations.   Additional provisions of the clearance procedure, which the majority fails to quote, indicate that the requirement that the pulverizer remain in operation contemplates a restart of the pulverizer after it has been tripped, rather than, as the majority erroneously suggests, that the pulverizer cannot be tripped until it is purged.   Also, no time period is prescribed for the clearance procedure [*37]   other than a provision that the fuel load be cleared "as soon as possible." Section 565 of NFPA No. 85E imposes an essentially similar sequence of clearance steps, n13 but does not contain the "as soon as possible." requirement. n14

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n13 These provisions provide in full as follows:

NFPA No. 60-1973

624.   Clearing Procedures for Pulverizers Tripped Charged with Fuel. In order to minimize hazards caused by accumulations within the pulverized fuel system equipment, as discussed in Section 616, the following procedure shall be used to clear fuel from the system as soon as possible after it has been tripped while containing a charge of fuel.

6241.   Isolate all shutdown or tripped pulverizers as recommended by manufacturer.

6242.   Start up one pulverizer in accordance with the principles and sequences listed in Section 621(a) through (f).

6243.   Continue to operate the pulverizer until empty, and in normal condition for shutdown. When the operating pulverizer is empty of fuel, proceed to another pulverizer and repeat the procedure until all are cleared of fuel.

NFPA No. 85E-1974

565.   Clearing Procedure for Pulverizers and Fuel Burning Equipment

In order to minimize hazards caused by accumulations within the pulverizer, as discussed in 564, the following procedure shall be used to clear coal from the pulverizing and fuel burning equipment after a master fuel trip or a trip of individual pulverizers.

(a) Isolate all non-operating or tripped pulverizers from the furnace.

(b) Purge the furnace and start up in accordance with 522(a) through (i) following a boiler fuel trip.

(c) Light the igniters on all burners of the pulverizer to be cleared.   After making sure that the igniters are lighted and are providing appropriate ignition energy for the main burner, start the pulverizing equipment following the equipment manufacturer's recommendation.

(d) Continue to operate the pulverizer until empty, and in a normal condition for shutdown. If boiler conditions will permit a firing rate greater than the capacity of one pulverizer operating within its normal operating range, the first pulverizer should be kept in operation in accordance with 564.   If the first pulverizer cannot be left in service, shut it down in the prescribed manner leaving it cool and as free of coal as practical.

(e) Repeat the procedure for all other pulverizers that had been tripped charged with coal. The procedure and operating principles outlined in Section 55 and 564 should be followed.

(Emphasis added.)

n14 In his brief the Secretary argues that section 624 of what he identifies as the "1975" edition of NFPA No. 60 contains the same provisions as the 1974 edition of NFPA No. 85E.   I have not been able to locate an edition of NFPA No. 60 dated 1975.   There is, however, an edition dated 1973, the provisions of which are identical to those quoted by the Secretary.   I will assume that the Secretary while referring to NFPA No. 60-1973 inadvertently misidentified that code as a 1975 edition.   Contrary to the Secretary's assertion, the provisions of the two codes, NFPA No. 60 and NFPA No. 85E, are not the same in that the phrase "as soon as possible" appears in the 1973 edition of NFPA No. 60 but not in the later, 1974, edition of NFPA No. 85E.   The deletion of this language suggests that the industry no longer makes any recommendation regarding the period of time for restarting a pulverized which has been tripped while containing an accumulation of heated coal. This significant change in the requirements of the NFPA codes over a short period of time further supports the conclusion that the NFPA standards should not be used as dispositive proof of industry recognition of a hazard. Indeed, both codes expressly caution that their requirements must be tailored to both changes in technology and the particular circumstances of individual plants. Section 12 of NFPA No. 60 states:

No standard can be promulgated which will guarantee the elimination of pulverized fuel system explosions. Technology in this area is under constant development which will be reflected in revisions to this Standard.   The user of this Standard must recognize the complexity of pulverized coal firing as to the types of equipment and the characteristics of the fuel. Implementation of this Standard depends upon the judgment of the designer and the operator to suit the specific conditions under his responsibility (emphasis added).

The foreword to NFPA No. 85E contains similar language with respect to furnace explosions.

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In any event as Judge Wienman properly determined, the NFPA codes are advisory insofar as they exempt pre-existing installations such as Respondent's.   Under Commission precedent, therefore, the NFPA codes cannot be used to establish recognition of a hazard under 29 U.S.C. §   654(a)(1).   A. Prokosch & Sons Sheet Metal, Inc., 80 OSAHRC 96/A2, 8 BNA OSHC 2077, 1980 CCH OSHD P24,840 (No. 76-406, 1980). n15

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n15 Contrary to footnote 5 of the lead opinion, the advisory nature of the NFPA standards extends to the conduct at issue in this case because, as I have explained, the hazard of which recognition must be shown involves a specific work practice of the employer.   Since the majority errs in its definition of the hazard in broad, generic terms, its conclusion that the NFPA codes can be used for showing recognition of this hazard is misplaced.

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For these reasons, I would affirm the judge's decision to vacate the citation.