1981 Fall M e e t i n g

T e c h n i c a l C o m m i t t e e D o c u m e n t a t i o n

TCD-81 -F

A Compilation of the Documented Action on Comments Received by the Technical Committees Whose Reports Have Been Published

Prior to Consideration at the NFPA Fall Meeting

Sheraton Centre Toronto, Ontario, Canada

November 16-19, 1981

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N F P A

Copyright© 1981

All Rights Reserved

National Fire Protection Association, Inc. Batterymarch Park, Quincy, MA 02269

11M-9-81-SM Printed in U.S.A.

SUPPLE~NTARY

Report of Committee on Chemicals and Explosives

Correlating Committee

Robert W. Van Dolah, Chairman Pittsburgh, PA

Robert P. Benedetti, Secretary National Fire Protection Assn.

( Non voti ng )

William H. Doyle, Simsbury, CT Thomas E. Duke, Fire Prevention & Engineering Bureau of Texas Howard F. Kampsell,. Exxon Research & Engineering Co. Richard Y. Le Vine. Olin Corp. Samuel J. Porter, Falls Church, VA William J. Wiswesser, L~ Department of Agriculture

Technical Committee on Chemistry Laboratories

Howard F. Kempsell, Chaiman Exxon Research & Engineering Co.

Robert P. Benedetti, Secretary National Fire Protection Assn.

(Nonvoting)

L. H. Bradley, Viking Fire Protection Assoc. Inc. Red. NAS& FCA

Harlan R. Bratvold, Underwriters Laboratories Inc. Murray Cappers, Allied Chemical Corp. Rep. Chemical Manufacturers Assn.

John F. Clemons, Harvard University, MA Vernon L. Duke, Sandia National Laboratories Rep. NFPA Industrial Fire Protection Section

J. Patrick Eaker, Kenosha, WI Rep. Campus Safety Assn.

Arden W. Forrey, Ph D, American Assn. for Clinical Chemistry Lawrence F. Gaff hey, US Environmental Protecti,on Agency John M. Galat, Schering-Plough Corp. Rep. National Safety Council

Leon D. Horowitz, American Mutual L iab i l i ty Insurance Co. Rep. Alliance of American Insurers

F. Owen Kubias, SCM Corp. Richard Y. Le Vine, Olin Corp. John R. Leach, National Insti tute of Health F. C. Loos, Houston Fire Oepartment,TX Rep. Fire Marshals Assn. of North America

Lawrence N. Nelson, Kewaunee Scientific Equipment Corp. David J. Pierce, NC Department of Labor D. L. Rhynard, Mobil Research & Developnent Center Rep. American PetrDleum Institute

Theodorus Ruys, Naramore, Bain, Brady & Johnson Rep. American Institute of Architects

Norman V. Steere, Norman V. Steere Assoc.

Alternates

John Fresina, Massachusetts Institute of Technology (Alternate to J. P. Eaker)

William D. Jordan, Harvard University, MA (Alternate to J. F Clemons)

William B. Meyer, Bendix Corp. (Alternate to V. Duke)

George F. Murphy, Kennecott Copper Co. (Alternate to National Safety Council)

Charles C. Randall, US Environmental Protection Agency (Alternate to L. Gaff hey)

Nonvoting

Ralph Berger, Skinner & Sherman Laboratories Inc.

Technical Committee on

Electrical Equipment in Chemical Atmospheres

Richard Y. Le Vine, Chairman Olin Corp.

Robert P. Benedetti, Secretary National Fire Protection Assn.

( Non voting)

F. D. Alroth, Underwriters Laboratories Inc. William Calder, The Foxboro Co. Rep. Instrument Society of America

John D. Campbell, Brown & Root Inc. Rep. IEEE

P. M. Fitzgerald, Factory Mutual Research Corp. Leland J. Hall, The Mill Mutuals Rep. NFPA National Electrical Code Committee

John T. Higgins, Dow Corning Corp. Rep. NFPA Industrial Fire Protection Section

Roger L. King, US Bureau of Mines William I. Morton, E. I. Dupont De Nemours & Co. Rep. Chemical Manufacturers Assn.

Frank E. Rademacher, Industrial Risk Insurers John E. Rogerson, Procter & Gamble Co. R. F. Schwab, Allied Chemical Corp. Walter A. Short, Crouse-Hinds Co. Rep. NEM~

George H. St. Onge, Exxon Research & Engineering Co. Rep. American Petroleum Insti tute

Alternates

Albert A. Bartkus, Underwriters Laboratories Inc. (Alternate to F. Alroth)

Bruce E. Ewers, Phillips Petroleum Co. (Alternate to G. St. Onge)

Frederick L. Maltby, Drexelbrook Engineering Co. (Alternate to W. Calder)

John Rennie, Factory Mutual Research Corp. (Alternate to P. M. Fitzgerald)

Thomas S. Staron Jr., Industrial Risk Insurers (Alternate to F. E. Rademacher)

This l is t represents the membership at the time the Committee was balloted on the ~ext of this edition. Since that time, changes in the membership may have occurred.

The Supplementary Report of the Committee on Chemicals and Explosives is presented in 2 parts.

Part I, prepared by the Technical Committee on Chemistry Laboratories, proposes for adoption a Supplementary Report which documents its action on the public comments received on its Report on NFPA45-1975, Standard on Fire Protection for Laboratories Using Chemicals, published in the Technical Committee Reports for the 1981 Fall Meeting.

Part I has been submitted to letter ballot of the Technical Committee on Chemistry Laboratories which consists of 20 voting members; al l of whom voted a f f i rmat i ve ly .

Part I has also been submitted to l e t t e r bal lo t of the Correlating Committee on Chemicals and Explosives, which consists of 7 voting members; all of whcm voted a f f i rmat ive ly .

Part I I , prepared by the Technical Committee on Electr ical Equipment in Chemical Atmosphere, proposes for adoption a SupplB~entary Report which documents i t s action on the public comments received on i t s Report on NFPA 496-1974, Standara on Purged and Pressurized Enclosures for Elect r ica l Equipment in Hazardous Locations, published in the Technical Committee Reports fo r the 1981 Fall Meeting.

Part I I has been submitted to l e t t e r bal lo t of the Technical Committee on Electr ical Equipment in CHemical Atmospheres which consists of 14 voting members; al l of whom voted a f f i rmat i ve ly .

Part I I has also been submitted to l e t t e r bal lot of the Correlat ing Committee on Chemicals and Explosives which consists of 7 votingmB~bers; al l of whom voted a f f i rmat i ve ly .

4~- i - (General): Reject SUBMITTER: Clayton Hathaway, Monsanto Company COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Recommend that the Committee review al l new p r o p f ~ s e ~ o n s for compliance with the new proposed scope and r~s t r i c t the standard to f i r e prevention. SUBSTANTIATION: Several sections stray beyond the scope of the standard as defined in Section i -2.1. Examples include Sections 5-5.3, 6-4.1, 6-4.2, 6-5.6, and 6-10. These and several other ~ections are more related to industr ia l hygiene or other concerns rather than f i r e safety for occupants or property. The proposal dwells nn condltions for hood use relevant to protection of personnel in normal use, not f i r e prevention. I t does so inadequately, ignoring the role of poor work practices. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: No substantive recommendations submitted. The ~ t ~ [ e e ~ t h a t the examples cited are very de f i n i t e l y related tn the scope of NFPA 45.

45- 2 - ( I - i and E~eption No. 1): Reject StIBMITTER: EreH J. Savaglio, Arizona Hospital Assoc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATINN: Change Exception No. 1 to read: Exception No. i : It does not apply to laboratory work areas associated with health related ins t i tu t ions and which are corered by NFPA 56C, Safety Standard for Laboratories in Health-Related Inst i tu t ions. SUBSTANTIATION: Not a l l laboratory work for Health-Related Inst i tu t ions is carried out in buildings in which patient care is provided. The health related laboratory work may be in a separate non-patient care building ei ther on the same campus as the patient care f a c i l i t y or at another o f f campus location. COMMITTEE ACTION: Reject.

Delete "in huildinqs in which patient care is provided" from Exception No. 1 of I -1.1. COMMITTEE COMMENT: The intent of NFPA 45 is to cover a l l laboratories not covered by NFPA 56C. The deletion made by the rommittee s lmpl i f ies the interpretat ion of the Exception.

45- 3 - (1-1.1, Exception No. 2 and 3, and i -4, Def in i t ions) : Reject SUBMITTER: D.W. Owen/O.M. Slye, Mobil Research & Development Corp. ~ E N T ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete Exception No. 2 and Exception No. 3 from Section 1-1.~i~and delete the def in i t ion of "P i lo t Plant" from Section 1.4. SUBSTANTIATION: There is r,o clear delineation between a laboratory and a small p i l o t plant or chemical manufacturing ~lant. The inclusion of these Exceptions causes confusion in application of the standard. A better de f in i t ion of a Laboratory Usinq Chemicals needs to be developed to more accurately define the scope of the standard. References to laboratories that are re~I ly p i lo t plants or manufacturing plants should be eliminated. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee attempted to devise a J is t inc t inn between laboratories and p i l o t plants and between laboratories and manufacturing operations. They were not successful. Io eliminate these two exceptlons would resul t in more confusion, rather than less, in determining the app l i cab i l i t y of NFPA 45.

45- ~ - ( i -> .2 ) : R~ject SUBMITTER: Ealph Schmidt, Los Alamos National Laboratory COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Appropriate section should be added. SUBSTANTIATION: To have an overal l standard, a l l areas of ~ a t o r y ac t i v i t i es should be considered not only related to f i r ~ and e×plnsion. COMMITTEE ~ETIDN: Reject. COMMITTEE COMMENT: No specif ic recommendations submitted.

45- 5 - (I-4 O~f in i t ions): Accept SHBMITFER: Robert E. Shreyer, Mason & Hanger-Silas Mason Co., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Apparatus. Furniture, laboratory hoods, ~entrifuges, re f r igera tors , and commercial or made-on-slte equipment used in a laboratory. SUJSTANTI~TION: It is bad prac t i ce to use the word being def ined in the de f in i t ion .

Apparatus. Furnlture, laboratory hoods, centrifuges, re f r igera tors , and commercial or made-on-site apparatus, or equipment used in a laboratory. COMMITTEE ACTION: Accept.

PART I

45- 6 - (1-4 Def in i t ions) : Reject SUBMITTER: Robert E. Shroyer, Mason & Hanger-Silas Mason Co., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Safety Can. An approved sturdy container, of not more than f ive gal capacity, having a spring-closing l id and spout cover and so designed that i t w i l l safely re l ieve internal pressure when subjected to f i r e exposure. The spout shall be equipped with a screen that acts as a flame arrester and tends to prevent the propagation of f i r e and explosion back into the container. SUBSTANTIATION: The de f ln i t ion of safety can does not specify material of safety can construction or flame arrester in the spout.

Safety cans should be of sturdy cons t ruc t ion so they do not soften, deform or burn through when exposed to f i r e .

The flame arrester is needed to prevent the propagation of f i r e and explosion back into the safety can. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The def in i t ion of NFPA 45 is taken d i rec t l y from NFPA 30 which has ju r i sd i c t i on . Any suggested change to th is de f in i t ion must be submitted to the Committee on General Storage of Flammable Liquids.

45- 7 - (1-4 Def in i t ions) : Reject SUBMITTER: Ralph Schmidt, Los Alamos National Laboratory COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Unattended laboratory operations are permitted in special occasions. A wr i t ten approval is required by local authori ty having ju r i sd i c t i on . SUBSTANTIATION; Provisions should be made for unattended continuous operating permit. There are experiments that can be operated continuously with minimum potential hazard. There should be an i n i t i a l approval system. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The subject is adequately addressed in Chapter 9.

45- 8 - (3-1.6 and 3-1.7): Reject SUBMITTER: Dennis O. Kubicki, NASA COMMENT ON PROPOSAL NO.: 45-11 RECOMMENDATION: Section 3-1.7 should be revised as fol lows: 3-1.7 Al l f loor openings shall be sealed to prevent the passage of smoke and f i r e between f loors . Openings shall be curbed when the amount of flammables present in the laboratory work area excees _ _ gal. SUBSTAN~ON: While I take no exception with the need for sealing of f loor penetrations to prevent ver t i ca l f i r e and smoke spread, any requirement for curbing should take into account the amount of flammables present. Limited quantit ies do not warrant f loor curbing. COMMITTEE ACTION: Reject.

Revise 3-1.-'~-o read: " . . . . f i r e endurance rating and to prevenL the passage of smoke, f i r e , or vapors between f loors or through wai ls. (See 6-11.3.)"

Also, revise 3-1.7 to read: 3-1.7 Al l f l oo r openings shall be sealed or curbed to prevent l iquid leakage to lower f loors . COMMITTEE COMMENT: The Submitter has pointed out certain inadequacies and confusing wording in 3-1.6 and 3-1.7. The changes made should eliminate these problems. However, the Committee does not agree that a lower l im i t can be specified below which curbing or sealing is not needed.

45- 9 - (3-1.7 Exception (New)): Reject SUBMITTER: Carroll V. LovetL, Easton, CT COMMENT ON PROPOSAL NO.: 45-11 RECOMMENDATION: Add: Exception: Floor drains designed spec i f i ca l l y for spi l lage are acceptable to penetrate f i re - ra ted f l oo r / ce i l i ng and walls. SUBSTANTIATION" A f loo r drain could be considered as a f l oo r opening. ThT~ drain may be provided spec i f i ca l l y to carry o f f spi l lage.

An exception should be made or an additional statement made that f loor drains designed spec i f i car ly for spi l lage are acceptable. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: A f loo r drain, properly instal led and sealed to prevent leakage to lower f loors is considered to be a penetration, not an opening, and is therefore not prohibited by 3-1.7.

45- 10 - (3-3.1.1): Reject SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 4B-Not Applicable RECOMMENDATION: Add fol lowing: "Off ice buildings that contain laboratories may be required by the local authori ty having ju r i sd ic t ion to comply with the more res t r i c t i ve egress requirements of Chapter 13, Business Occupancies."

SUBSTANTIATION: To c l a r i f y intent, the exist ing paragraph addresses "Laboratory buildings" which are defined as "consisting wholly or p r inc ipa l l y of one or more laboratory uni ts . " The proposed paragraph cautions reader to check with local authori ty. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee's intent is adequately expressed and the def in i t ion of laboratory buildings addresses the concerns of the Submitter.

45- 11 - (3-3.2(a)): Accept in Pr inciple SUBMITTER: James L. Barnard, Mason & Hanger-Silas Mason Co., Inc. ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Revise 3-B.2(a) to:

(a) A laboratory work area contains an explosive hazard, and the provision of a second means of ex i t access would serve to reduce f a t a l i t i e s OF serious in jur ies to personnel within the laboratory work area in the event of an explosion. SUBSTANTIATION: The wording is unduly res t r i c t i ve in that i t would require a second means of access to an ex i t from an enclosed laboratory work area containing an explosive hazard, regardless of how small the room er the number of personnel with the room. COMMITTEE ACTION: Accept in Principle.

Revise 3-3.2(a) te read: (a) A laboratory work area contains an explosion hazard so

located that an incident would block escape from an access to the laboratory work area. COMMITTEE COMMENT: The above revised wording provides more de f in i t i ve guidelines.

45- 12 - (3-3.2(a)): Accept in Principle SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Dele-Te: (a) " . . .explosion hazard". SUBSTANTIATION: This broad requirement is not consistent with Chapter 5 or Appendix C philosophy. The need for a second ex i t depends upon the speci f ic hazard. A second ex i t is of no value in escaping a sudden explosion. In the case of an explosion hazard of low in tens i ty , simply stepping back a few ~teps may remove one from the hazard area. Rather than a second ex i t , shielding or other protection proposed in Appendix C is the appropriate solut ion. Adding a second ex i t is very cost ly in terms of f loor space and construction costs when the benefit is dubious. COMMITTEE ACTION: Accept in Pr inciple. COMMITTEE COMMENT: See Comment i i .

45- 13 - (3-3.2(a)) : Accept in Pr inciple SUBMITTER: A.J. Pryor, DOE COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Del~te subitem (a) on " . . .explosion hazard." SUBSTANTIATION: This broad requirement for a second ex i t from any laboratory containing an explosion hazard is an excessive and expensive requiremenL and one that w i l l not solve the problem. A second ex i t cannot be expected to be of value in protecting personnel from an explosion hazard. Other protect ive measures as proposed in Appendix C may be more appropriate. COMMITTEE ACTION: Accept in Pr incip le. COMMITTEE COMMENT: See Comment 11.

45- 14 - (3-3.2): Aocept in Principle SUBMITTER: George Courtis, Monsanto Research Corp. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: The cost of providing a second means of access to an ex i t to exist ing f a c i l i t i e s is un jus t i f iab le . In many cases the provision of a second ex i t is impossible due to the l oca l i t y of the laboratory unit and i ts re lat ion with other f a c i l i t i e s . An explosion w i l l be very rapid-making; therefore, the need of a second access to an ex i t is unnecessary. SUBSTANTIATION: A second means of access to an ex i t shall be provided from a laboratory work area i f a laboratory work area contains an explosion hazard. This is not feasible due to high cost and rap id i ty of an explosion. COMMITTEE ACTION: Accept in Pr inciple. COMMITTEE COMMENT: See Comment 11.

45- 15 - (3-3.2(e)) : Reject SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delet~ sub item (e) "Compressed Gas Cyl inders. . . " SUBSTANTIATION: The explosion event of the sudden rupture of a gas cyl inder would be over so rapid ly that a second ex i t would be useless. Our experience in using gas cylinders extensively throughout laboratories is excel lent. Sub item (e), (3) allows for using judgement, but an overzealous author i ty having ju r i sd ic t ion w i l l l i ke l y require a l l labs containing a gas cyl inder to have two exi ts.

COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Items ( i ) , (2) and (3) of 3-3.2(e) adequately r es t r i c t the application of the requirement for a second means of egress only to those cases where a severe r isk is presented. Al l three conditions must exist before the requirement applies, The Committee feels this is a reasonable requirement.

45- 16 - (3-3.2(e)) : Reject SUBMITTER: A.J. Pryor, DOE COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete sub item (e) on "compressed gas cyl inders." SUBSTANTIATION: The requirement for a second ex i t from a laboratory containlng a com~ressed gas cyl inder as specif ied is overly r es t r i c t i ve and unnecessary. The safety record in the use of compressed gas cylinders does not j u s t i f y th is very cost ly requirement. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment 15.

45- 17 - (3-3.2(e)): Reject SUBMITTER: George Courtis, Monsanto Research Corp. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: A second means of access to an ex i t shall not be provided from a laboratory work area i f a compressed gas cyl inder is in use. SUBSTANTIATION: The cost of providing a second means of access to an ex i t to exist ing f a c i l i t i e s is un jus t i f iab le . In many cases the provision of second ex i t is almost impossible due to the l oca l i t y of the laboratory unit and i ts re lat ion with other f a c i l i t i e s . Also a gas explosion w i l l be very rapid-making; therefore, the need of a second access to an ex i t is unnecessary. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment 15.

45- 18 - (3-3.2(e) and ( f ) ) : Reject SUBMITTER: Ralph Schmidt, Los Alamos National Laboratory COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Recommend delete lines 3-3.2(e) (1) and ( f ) . SUBSTANTIATION: Compressed gas cyl inder and cryogenic dewars that have DOT-OSHA approved r e l i e f devices and are properly secured minimize the hazard.

Inert gases He, Np etc. , should be excluded. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comments 15, 19 and 20.

45- 19 - (3 -3 .2( f ) ) : Accept SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete sub item ( f ) . SUBSTANTIATION: The presence of a cryogenic l iquid does not j u s t i f y a second ex i t . We have had such operations for years and our experience does not j u s t i f y a second ex i t . COMMITTEE ACTION: Accept.

45- 20 - (3 -3 .2 ( f ) ) : Accept SUBMITTER: A.J. Pryor, DOE COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete sub item ( f ) f l u i ds . " on "cryogenic SUBSTANTIATION: The broad requirement for a second exi t in a l l laboratories containing cryogenic f lu ids is excessive and unnecessary. We know of no experience to j u s t i f y this expensive requirement. COMMITTEE ACTION: Accept.

45- 21 - (3 -3 .2 ( f ) ) : Accept in Principle SUBMITTER: James L. Barnard, Mason & Hanger-Silas Mason Co., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Revise 3-3.2( f ) to:

( f ) A laboratory work area contains cryogenic f lu ids which, with a single access to an ex i t would prevent safe egress in the event of accidental release. SUBSTANTIATION: The wording is unduly r es t r i c t i ve in that i t would require a second means of access to an ex i t from an enclosed laboratory work area which contains cryogenic f l u ids , regardless of the quantity, how they are control led, and how small the room. COMMITTEE ACTION: Accept in Principle.

See Comment 19. COMMITTEE COMMENT: The Committee agrees that 3-3.2( f ) is unduly r es t r i c t i ve .

45- 22 - (3 -3 .2 ( f ) ) : Accept in Pr inciple SUBMITTER: Stephen C. Sadler, Monsanto Research Corp. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Mandatory requirements are not feasible for small quantit ies of cryogenic materials. Standard should set speci f ic quantit ies at which level mandatory requirements would be e f fec t i ve . SUBSTANTIATION: Mandatory requirement fo r "second means of access" when cryogenic f lu ids are located in the area. This is not feasible when small quantit ies of cryogenic materials are in use. COMMITTEE ACTION: Accept in Pr inciple. COMMITTEE COMMENT: See Comment 19.

45- 27 - (5-1.2(e)) : Reject SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: At the end of the sentence in 5-I .2(e) add the fol lowing sentence: "Inside walls shall be of explosion-resistant construction." SUBSTANTIATION: This section makes no di rect mention of the need for inside walls to be explosion-resistant; yet i t is implied in Section 5-2. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The current wording of 5-1.2(e) implies that insu f f i c ien t explosion vent area w i l l necessitate explosion-resistant construction for in te r io r wal ls.

45- 23 - (4-2.1.1): Accept SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add words "by Table 3-1" fol lowing "may be required." SUBSTANTIATION: C la r i f y intent which is presented in Table 3-1; otherwise, i t may be interpreted "as required by local authori ty having j u r i sd i c t i on . " COMMITTEE ACTION: Accept.

45- 24 - (4-2.4): Accept in Principle SUBMITTER: Dennis J. Kubicki, NASA COMMENT ON PROPOSAL NO.: 45-21 RECOMMENDATION: Section 4-2.4 should be retained with a suggested revision as fol lows: 4-2.4 The discharge of an automatic f i r e extinguishing system shall activate the building f i r e alarm system. In the absence of a manual f i r e alarm, the extinguishing system shall act ivate an audible alarm capable of being heard throughout the premises. SUBSTANTIATION: The Technical Committee intends to delete Section 4-2.4. The j u s t i f i c a t i o n is that the alarm requirement is adequately covered by the referenced standards. However, not a l l of the standards require alarms (NFPA 15 and 69). In addition, NFPA 17 would accept an " indicator" in l ieu of an alarm, F ina l ly , a l l of the requirements for alarms would permit a local alarm at a control panel. This would, and has in the past, resulted in building occupants being unaware of a f i r e of su f f i c ien t magnitude to activate the extinguishing system. COMMITTEE ACTION: Accept in Pr inciple.

Reinsert or ig inal 4-2.4 to read: 4-2.4 The discharge of an automatic f i r e extinguishing system shall activate an audible alarm system on the premises. COMMITTEE COMMENT: While the Committee agrees with the need for a discharge alarm, they feel i ts purpose is to not i fy appropriate personnel in the area that the system has activated. The Committee does not agree with the need for an alarm audible throughout the premises. The Committee w i l l also no t i f y those Committees, ( i . e . , NFPA 15, 17, and 69) whose standards do not require a discharge alarm.

45- 25 - (4-5.2.1, through 4-5.2.1.3 (New)): Reject SUBMITTEP: Vic Humm, Vic Humm & Assoc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RLCUMMLN~ArLON: Add: 4-5.2.1 Any automatic or manual extinguishing system shall be monitored by the f i r e alarm or protect ive signaling system for alarm, trouble, and supervision signal. 4-5.2.1.1 A/arm signal shall mean the actuation of the extinguishing system. 4-5.2.1.2 Trouble signal shall mean monitoring an impairment or loss of e lec t r i ca l actuation c i rcu i ts or pathways. 4-5.2.1.3 Supervisory signal shall mean monitoring the status of system components that would cause the automatic or manual extinguishing system not to be funct ional . SUBSTANTIATION: When a f i r e alarm system is instal led and the premise has automatic f i r e extinguishing systems, each respective extinguishing system shall be monitored by the premise's f i r e alarm or protect ive signaling system. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The concerns of the submitter are not within the scope of NPPA 45. They should be directed to the Committees of the specif ic extinguishing systems.

45- 26 - (5-1.2(e)): Accept in Principle SUBMITTER: Carrol l V. Lovett, Easton, CT ~ N PROPOSAL NO.: 45-22 RECOMMENDATION: Add to e i ther (b) or (e): " . . . . s u f f i c i e n t explosion venting for the equipment which is vented safely to the outside." SUBSTANTIATION: No mention is made of providing explosion venting for the equipment (vented to the outside). COMMITTEE ACTION: Accept in Pr inciple.

Add to the parenthetical in 5-1.2(b): " . . . .exp los ion venting directed to a safe location; . . . . " COMMITTEE COMMENT: The Committee feels that the subject need only be covered in item (h).

45- 28 - (5-2): Accept in Principle SUBMITTER: Carrol l V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 45-22 RECOMMENDATION: Divide Explosion-Resistant Construction into two (2) subparts, one for building construction and one for equipment construction. SUBSTANTIATION: This section applies only to the building construction but explosion-resistant construction can also apply to the equipment, reactor, etc. COMMITTEE ACTION: Accept in Pr incip le.

Add: "equipment or" between the words "explosion-resistant" and "enclosures" in 5-1.2(b) COMMITTEE COMMENT: The concerns of the submitter are addressed in 5 - i .2 (b ) . Section 5-2 applies only to building construction.

45- 29 - (5-3(a)): Reject SUBMITTER: Carrol l V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 45-22 RECOMMENDATION: Revise 5-3(a): (a) "Fragments w i l l not cause in jury to occupants in other buildings or areas," SUBSTANTIATION: Section (a) is very r es t r i c t i ve . Is the Committee concerned about the fragments h i t t ing the occupied buildings or causing in jury to the occupants in the buildings or areas? What i f fragments h i t a sol id wall of an occupied building or due to distance the fragments h i t an occupied building with no ve loc i ty , is this of concern? COMMITTEE ACTION: Reject. COMMITTEE COMMENT: I t is not possible to pre-determine what fragments w i l l be produced or what the terminal ve loc i ty of the fragments w i l l be.

45- 30 - (5-5.3): Accept SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change Section 5-5.2 to 5-5.2* and put the wording of Section 5-5.3 in Appendix A as Section ~-5.2. SUBSTANTIATION: This Section is rea l l y an Appendix A item as is indicated by the use of the words "may be applied." I t applies to Section 5-5.2. COMMITTEE ACTION: Accept.

45- 31 - (6-4.2): Hold for Further Study SUBMITTER: A.J. Pryor, DOE COMMENT ON PROPOSAL NO,: 45-Not Applicable RECOMMENDATION: Delete Sub item 6-4.2. SUBSTANTIATION: This requirement is not j u s t i f i e d on the basis that the control of the use of hazardous chemicals can be and has been accomplished through several other methods. Experience with these other methods has been sat is factory . This proposed requirement is an extremely expensive one and is not j us t i f i ed on the basis of experience. COMMITTEE ACTION: Hold for Further Study. COMMITTEE COMMENT: The Committee, before i t changes this requirement, would l ike to receive information on the al ternat ive control methods suggested by the Submitter.

45- 32 - (6-4.2 Exception No. 2): Reject SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Revise Exception No. 2 to read "Class C laborator ies." SUBSTANTIATION: The exist ing Exception is too str ingent. In fac t , almost any room called a laboratory would have more than a l i t r e of flammable l iquid or 30 c u f t of flammable compressed gas. With energy conservation e f fo r ts necessitating shutting o f f hood exhausts when not used and night time curtailment of building vent i la t ion , i t is d i f f i c u l t to assure a negative pressure gradient from room to hallway. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: This subject has been discussed previously. The Committee feels this is the best cu t -o f f for this Exception that can be developed at this time.

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45- 33 - (6-4.2 Exception No. 2): Reject SUBMITTER: Ralph Schmidt, Los Alamos National Laboratory COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add to Exception No. 2: Does not apply to areas that use toxic gas or material . SUBSTANTIATION: This Exception should be modified to consider toxic material. Laboratories can comply with Exception No. 2 but s t i l l contain toxic gases or materials. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Exception No. 2 only applies to flammable l iquids or to flammable gases. The Exception already accomplishes what the submitter recommends.

45- 34 - (6-4.3" and A-6-4.3 (New)): Hold fo r Further Study SUBMITTER: Gerhard W. Knutson, Industr ial Health Engineering Assoc., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Replace present 6-4.3 with the fol lowing wording and add Appendix A-6-4.3: 6-4.3* Care shall be exercised in the selection and placement of the air supply fixtures to ensure that the throw from the fixtures at the face of the hood (the velocity of air emanating from the supply fixtures and measured at the face of the hood without the hood exhaust system on) shall be less than one-half the face velocity of the hood. A-6-4.3 Inadequate selection and/or placement of supply air fixtures can destroy the efficiency of the laboratory fume hood. SUBSTANTIATION: The warning that the selection and placement of air supply diffusion devices requires some care to avoid air currents that would adversely affect the performance of the fume hood is clearly indicated. However, as we discussed in our research project for ASHRAE (RP-70), the effect of the supply air fixtures may be mo,~e significant than the face velocity of the hood. Consequently, Section 6-4.3 as presently worded seems to be a substantial understatement of the caution required. Therefore, we suggest the above wording. COMMITTEE ACTION: Hold for Further Study. COMMITTEE COMMENT: The Committee has not reviewed the research report cited by the submitter. The Committee further feels that the report wi l l require considerable study. The Committee would appreciate receiving a copy of this report for discussion at their next meeting.

45- 35 - (6-5.3): Reject SUBMITTER: Vernon L. Duke, Sandia National Laboratories ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete or revise to add "except above cei l ing return a i r plenums are permissible within laboratory uni ts." SUBSTANTIATION: This would preclude using above cei l ing spaces as building HVAC system return air plenums. COMMITTEE ACTION; Reject. COMMITTEE COMMENT: The Committee feels that the proposed Exception would decrease the level of safety provided by 6-5.3.

45- 36 - (6-5.3): Reject SUBMITTER: A.J. Pryor, DOE COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete 6-5.3. SUBSTANTIATION: This requirement prohibi ts the use of ce i l ing plenums as return routes for HVAC systems. This would be an exceedingly expensive res t r i c t ion which is not j u s t i f i e d on the basis of experience. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment 22.

45- 38 - (6-5.5): Reject SUBMITTER: Ralph Schmidt, Los Alamos National Laboratory COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Reference to OSHA Standard 29 CFR 1910.94. SUBSTANTIATION: OSHA Laws have requirements on face ve loc i t ies . COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The cited OSHA reference is not f i r e protection related.

45- 39 - (6-6.1): Reject SUBMITTER: Gerhard W. Knutson, Industr ial Health Engineering Assoc., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add to present Section 6-6.1 the following clause: ", and shall conform with SMACNA duct construction standards." SUBSTANTIATION: The section on duct construction is somewhat inadequate. Although this section is quite appropriate for a NFPA standard, it may also be appropriate to reference SMACNA standards. This would admit that there is more in the design and selection of adequate ductwork than a concern about the f lammabil i ty of the duct construction. At the same time, i t would emphasize that aspect of the duct construction that this standard mosty appropriately addresses. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The referenced SMACNA standards are referenced in NFPA 90A, which is referenced in NFPA 45.

45- 40 - (6-6.3 Exception (New)): Reject SUBMITTER: Carrol l V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add: Exception: The flame spread index for ducts and duct l inings does not apply i f automatic sprinklers are instal led in a l l areas where the ducts pass and for ducts without l inings i f automatic sprinklers are instal led inside the ducts. Note: Special provisions may be required to protect the sprinklers from corrosion, etc. located inside the ducts. SUBSTANTIATION: This section is over r es t r i c t i ve i f automatic sprinklers are instal led over and in ducts.

NFPA 101 28-3.3.2 has "no occupancy requirements" for in te r io r f in ish . Class A, B or C materials may be used even in nonsprinklered buildings, Class 8 in te r io r f in ishes are permitted in ex i t enclosures. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The unique f i r e hazards of combustible ducts require this addit ional level of protection.

45- 41 - (6-8.4): Reject SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change "flammable vapors" to "flammable vapor-air mixtures" "Combustible dusts" to "Combustible dust-air suspensions" and change "are passed through..." to "may be passed through." SUBSTANTIATION: To c l a r i f y intent. I f only traces of flammable vapors or combustible dusts pass up an exhaust system, then non-ferrous fan materials are not necessary, I t is only when the probab i l i t y exists that a flammable gas-air mixture or combustible dust-a i r suspension may at some time exist that such precaution is warranted. COMMITTEE ACTION: Reject. COMMITTEE COMME--#T: The current wording represents the level of safety deemed acceptable by the Committee.

45- 37 - (6-5.4): Reject SUBMITTER: Gerhard W. Knutson, Industr ial Health Engineering ASSOC., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add as the second sentence of 6-5.4 the fol lowing: "To ensure the negative pressure in the duct, the exhaust fan shall be located outside of the building or in a remote penthouse, and the ductwork downstream of the exhaust fan shall not pass through occupied spaces. SUBSTANTIATION: The intent of this Section is c lear ly to prevent leakage of contaminated a i r from the seams oF the exhaust pipe. Although i t does not say so, this section implies that the exhaust fan or blower should be located outside or in a remote penthouse. Since many chemists who order laboratory fume hoods and supervise the i r ins ta l la t ion have had no background in design of vent i la t ion systems, i t seems important to state e x p l i c i t l y that the fan should be outside or in a remote penthouse. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee feels that 6-5.4 adequately expresses the performance required.

45- 42 - (6-9.1.3 and A-6-9.1.3): Accept in Principle SUBMITTER: Clayton Hathaway, Monsanto Company COMMENT ON PROPOSAL NO.: 45-1 RECOMMENDATION: Add the fol lowing: "A l ternat ive ly , a pan or t ray may be used to contain flammable l iquid in the event of a sp i l l (see Section 9-1.2.2)." SUBSTANTIATION: Proposed is speci f icat ion, not performance standard. Trays, pans and the l ike provide reasonable al ternat ives as directed in Section 9-1.2.2. COMMITTEE ACTION: Accept in Pr inciple.

Revise 6-9.1.3 to read: "Laboratory hoods shall be provided with a means of containing minor sp i l l s . "

Revise A-6-9.1.3 to read: "The means of containing minor sp i l l s may consist of a 1/4 in. recess in the work surface, use of pans or trays, or creation of a recess by ins ta l l lng a curb across the f ront of the hood and sealing the jo in ts between the work surface and the sides, back, and curb of the hood." COMMITTEE COMMENT: The Committee feels that the wording above adequately expresses the performance c r i t e r i a suggested by the Submitter.

45- 43 - (6-9.3 and A-6-9.3 (New)): Reject SUBMITTER: Gerhard W. Knutson, Industr ial Health Engineering Assoc., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add to Section 6-9.3 the fol lowing sentence: "Whenever a hood is provided with a sl id ing sash, the hood shall be provided with a bypass opening designed so that the face ve loc i ty at a l l sash posit ions w i l l be no more than three times the design face ve loc i ty .

Add: A-6-9.3 I t is necessary to provide a bypass to prevent such great increases in face ve loc i ty by closing of sashes that materials in the hood are blown out of the hood or that experimental apparatus operation is compromised. SUBSTANTIATION: Section 6-9.3 prohibi ts " l ine of sight" openings but is not clear as to whether i t requires a bypass. In an e f f o r t to provide addit ional protection and reduce the a i r f low in a room, a ve r t i ca l l y - s l i d i ng sash is frequently lowered during the course of work in a laboratory fume hood. As this sash is lowered, i f there is no bypass for a i r , the face ve loc i ty of the hood increases s ign i f i can t l y . At some point, the face ve loc i ty could become su f f i c ien t to cause an experiment within the hood to be upset and toxic and/or flammable material to s p i l l . Consequently, i t may be advantageous to require a l l laboratory fume hoods with s l id ing sashes to be equipped with a bypass capabi l i ty . I f required, some qua l i f i ca t ion of the bypass capacity would be necessary, such as requiring the bypass to be designed so that the face ve loc i ty , at a l l sash posit ions, shall not be more than three times the design face veloc i ty . COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The recommended revision would not provide any ~ d i t i o n a l f i re--safety.

45- 47 - (6-9.5.1): Reject SUBMITTER: Clayton Hathaway, Monsanto Company COMMENT ON PROPOSAL NO.: 45-5 RECOMMENDATION: Delete "and the i r " so that i t reads "service controls shall be . . . " SUBSTANTIATION: There is no demonstrated need for the services to be located external to the hood. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment 17.

45- 48 - (6-9.6): Reject SUBMITTER: Gerhard W. Knutson, Industr ial Health Engineering Assoc., Inc. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add to Section 6-9.6 the fol lowing sentence:

The aux i l ia ry a i r hood shall be designed so that under normal operating conditions the aux i l ia ry a i r shall be e f f i c i e n t l y captured by the fume hood and not disrupt the heating and a i r conditioning system in the room with the sash posit ion ei ther f u l l open or f u l l closed and with the aux i l i a ry a i r supplied to the room 20OF warmer than the room temperature. SUBSTANTIATION: A major concern about aux i l i a ry a i r fume hoods is the fact that they can, and in many cases do, upset the a i r condi t ioning balance in the laboratory f a c i l i t y . Enclosed 7s a copy of a paper on aux i l i a ry a i r fume hoods by Knowlton Caplan of Industr ial Health Engineering Associates, Inc., which describes this concern. We believe Section 6-9.6 should be revised to add appropriate requirements. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The recommendation would not provide any additional f i r esa fe ty .

45- 44 - (6-9.4.1 and Exception (New)): Reject SUBMITTER: Carrol l V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add: Exception: This does not apply to e lec t r i ca l services and controls spec i f i ca l l y designed for the hazards to be used in the hood. SUBSTANTIATION: This is over r es t r i c t i ve for e lec t r i ca l services and controls designed for the hazard to be excluded from inside the hood. COMMITTEE ACTION: Reject.

Revise 6-9.4,1 to read: " . . . f i x e d e lec t r i ca l services and the i r con t ro l s . . . " COMMITTEE COMMENT: The requirement in question does not apply to ~ e c t r i c a l u t i l i za t i on equipment used in the hood.

45- 45 - (6-9.5.1): Accept SUBMITTER: Laurence N. Nelson, Kewaunee Sc ient i f i c Equipment Corp. ~ N PROPOSAL NO.: 45-39 RECOMMENDATION: Revise Section to read: 5-9.5.1 For new ins ta l la t ions or modifications of exist ing ins ta l la t ions , controls for laboratory hood services (gas, a i r , water, etc.) shall be located external to the hood and within easy reach. SUBSTANTIATION: This section as now wr i t ten would require the plumbing f i x tu re and i ts control to be outside the hood. This would require the rubber hoses leading from the f i x tu re out let to be run into the hood through the face opening. Hoses in this area would present a serious safety hazard. Hoses could be pulled o f f the serrated hose end of the f i x tu re by the lowering of the sash or personnel working in the hood, or the equipment to which the hoses are attached could be tipped over. For safe operation, the f i x tu re out let should be inside the hood; but, the controls should be outside the hood and within easy reach. COMMITTEE ACTION: Accept.

45- 45 - (6-9.5.1 Exception (New)): Reject SUBMITTER: Carrol l V. Lovett, Easton, CT ~ E N T ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add:--

This Hoes not apply i f controls are located outside the hood within easy reach. SUBSTANTIATION: This is over res t r i c t i ve for laboratory hood services located in the hood but the controls are located outside the hood within easy reach. There are several recorded incidents where gas services located in a hood prevented an accident/explosion that would not have been prevented i f i t were located outside the hood. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment 17.

45- 49 - (6-10.2): Accept in Part SUBMITTER: Clayton Hathaway, Monsanto Company COMMENT ON PROPOSAL NO.: 45-3 RECOMMENDATION: Delete reference to high t r a f f i c areas, Change exist ing to "shall not be located adjacent to single primary means of ex i t . " SUBSTANTIATION: This section combines concerns over location of a hood in an ex i t way and location by a source of turbulence. The proposed solution to the f i r s t concern f a i l s to recognize the existence of a secondary ex i t . Location near a main laboratory access door has not been demonstrated to increase r isk from f i r e . COMMITTEE ACTION: Accept in Part.

Revise 6-I0.2 to read: 6-10.2 For new ins ta l la t ions, laboratory hoods shall not be located adjacent to a single means of access to an ex i t or high t r a f f i c areas. COMMITTEE COMMENT: The inclusion of "high t r a f f i c areas" minimizes personnel exposure to the hazards within the hood.

45- 50 - (6-13.2(c) and 6-14.1(d)): Reject SUBMITTER: Clayton Hathaway, Monsanto Company COMMENT ON PROPOSAL NO.: 45-2 RECOMMENDATION: Add to 6-13.2(c) and 6-14.1(d) the fol lowing: "exhaust air f low rate or performance index" and add de f in i t ion as fol lows:

"Performance Index. A measure of the a b i l i t y of a laboratory hood to contain a material released in a hood under defined test condit ions." SUBSTANTIATION: These are speci f icat ion rather than performance standards. Alternat ives such as measurement of exhaust air f low rate (see Section 6-14.3) or performance testing by release of a tracer material within a hood are technical ly acceptable. Performance testing is a more val id measurement of effectiveness than face ve loc i ty . Face ve loc i ty has been shown in several recent reports to be an inadequate measurement of effect iveness. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The recommended procedures are not readi ly accepted test methods at this time.

45- 51 - (6-14.1): Reject SUBMITTER: john M. Galat, West Caldwell, NJ COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Expand Section 6-14.1 to include item "g" to read:

(g) HEPA f i l t r a t i o n systems for biological safety cabinets shall be tested for leak tightness using diocty l phthaIate (POP) or equivalent method.

Add Appendix item A-6-~4.1 to read: A-6-14.1 Leakage of HEPA f i l t r a t i o n system on biological safety cabinets could expose f i r e f ighters to airborne infectious micro-organisms. SUBSTANTIATION: Inspection, test ing and maintenance of hoods and vent i la t ion systems should include requirements for leak testing of HEPA f i l t r a t i o n systems on biological safety cabinets. F i l t e r leakage could expose f i r e f ighters to airborne infect ious micro-organisms.

6

COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The recommended change would exceed the scope of the standard because ( i ) normal leak tightness testing would not be applicable to emergency conditions; (2) under f i r e emergency conditions the biological r isk would be either substantially eliminated by elevated temperatures or of secondary concern.

45- 52 - (7-2.2.7 through 7-2.2.7.4 (New)): Reject SUBMITTER: John M. Galat, West Caldwell, NJ C--O-M--MENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add Section 7-2.2.7 to read: 7-2.2.7 Transfer rooms for Class I liquid~ from containers larger than f ive gal. 7-2.2.7.1 Transfer of Class I liquids from containers larger than f ive gal shall be carried out in a separate inside storage area as described in NFPA 30, or in an outside storage area. 7-2.2.7.2 Electrical wiring and equipment located in rooms used for transfer of C"ass I liquids from containers larger than f ive

l al shall be suitable for Class I, Division I classif ied locations see NFPA 70).

7-2.2.7.3 A grounding system shall be provided for rooms in which Class I liquids are transferred from containers larger than f ive gal (see NFPA 70). The maximum impedance of the grounding system shall not exceed six ohms. 7-2.2.7.4 Class I and II liquids shall be drawn from containers larger than f ive gal by means of an approved pump or other device drawing through an opening in the top of the container, or by gravity through an approved self-closing valve or self-closing faucet. SUBSTANTIATION: Section 7-2.2 includes definit ion of areas used for transfer of Class I liquids from bulk stock containers into smaller containers, but does not include specifications for "transfer rooms." Specifications for transfer rooms are also not included in NFPA 30. I t is suggested these be added for transferring from containers larger than f ive gal. COMMITTEE ACTION: Reject.

Revise 7-2.2.5 to read: 7-2.2.5 Transfer of Class I liquids to smaller containers from bulk stock containers not exceeding f ive gal in capacity inside a laboratory building or laboratory work area shall be made:

(a) in a laboratory hood; or (b) in an area provided with venti lat ion adequate to prevent

accumulations of flammable vapor/air mixtures exceeding 25 percent of the lower flammable l imi t ; or

(c) in a separate inside storage area, as described in NFPA 30, Flammable and Combustible Liquids Code. COMMITTEE COMMENT: The amendment to 7-2.2.5 c la r i f i es what the Committee intends. The submitter's proposed revision would conf l ic t with NFPA 30.

45- 53 - (7-2.2.7, 7-2.2.7.1" and A-7-2.2.7.1 (New)): Accept in Principle SUBMITTER: Norman V. Steere, Minneapolis, MN ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add Section 7-2.2.7 to read as follows: 7-2.2.7 Transfer rooms for Class I liquids from containers larger than f ive gal. 7-2.2.7.1" Transfer of Class I liquids from containers larger than f ive gal shall be carried out in a separate area outside of the building or in a separate inside area which shall be provided with f i r e protection appropriate to the quantities stored for transfer operations in the inside area. The f i r e protection requirements for inside transfer rooms shall be those described in NFPA 30 for inside storage rooms.

Add Appendix item A-7-2.2.7.1: A-7-2.2.7.1 I t is recommended that transfer operations not be carried out in inside storage rooms or cutoff storage areas because of the exposure of greater quantities to the hazards of transfer operation~. SUBSTANTIATION: NFPA 45 and other NFPA standards seem to lack adequate specifications for transfer of flammable liquids inside of laboratory buildings and laboratories. COMMITTEE ACTION: Accept in Principle.

Add new 7-2.2.6* to read: 7-2.2.6* Transfer of Class I liquids from containers of f ive gal or more capacity shall be carried out in:

(a) a separate area outside the building; or (b) in a separate area inside the building which meets the

requirements of NFPA 30, Flammable and Combustible Liquids Code, for inside storage areas.

Add Appendix A-7-2.2.6 to read: A-7-2.2.6 Where practicable, transfer operations should be separated from the storage of flammable and combustible liquids because of the exposure of greater quantities to the hazards of transfer operations. COMMITTEE COMMENT: The Committee's revision of the submitter's comment c ]ar i f ies the intent and does not conf l ic t with NFPA 30.

45- 54 - (7-2.2.6): Accept in Part SUBMITTER: Norman V. Steere, Minneapolis, MN COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Substitute for present Section 7-2.2.6 the following and add Appendix item: 7-2.2.6* Class I liquids shall not be transferred between metal containers unless the containers are e lec t r ica l ly interconnected by direct bonding, or by indirect bonding through a common grounding system in the room. The maximum impedance of the bonding shall not exceed six ohms. Metal containers larger than f ive gal in capacity shall be grounded during transfer operations.

Add to A-7-2.2.6 the following: "Metal containers of Class I liquids that are f ive gal in size should be grounded during transfer operations to minimize accumulation of static e lec t r i c i t y from the atmosphere." SUBSTANTIATION: Present wording of Section 7-2.2.6 does not require bonding between metal containers i f grounding of the dispensing containers alone is permitted, and the requirement would be clearer i f or ig inal ly proposed language was used. Also, the requirements for grounding are not clearly spelled out. COMMITTEE ACTION: Accept in Part.

Accept the f i r s t two sentences as new 7-2.2.7. Reject the third sentence and the Appendix item COMMITTEE COMMENT: The rejected parts would conf l ic t with NFPA 3U.

45- 55 - (8-1.3 and Exception): Accept in Principle SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change "or" to "and" in 8-3.1.

Under Exception, add before "is not required" the phrase "at the supply end." Add another sentence to read: " I f the distance between the supply valve point and use point does not exceea 20 f t , a valve at the use point is not required." SUBSTANTIATION: 8-1.3 Use of "and" for c la r i t y of intent. Exception. Change is intended to permit use of only the cylinder valve to control supply to a gas chroniotigraph, for example. Adding valves with inherent vent piping which is not reasonable i f distances are short. COMMITTEE ACTION: Accept In Principle.

In 8-1.3, replace "or use" with "and at al l points of use." Add an Exception to read: "A valve at the point of use is not required i f there is a supply shut-off valve within immediate reach of the point of use." COMMITTEE COMMENT: The revision and the Exception more clearly expresses the intent of the Submitter.

45- 56 - (8-2, Table 8-2 and Notes 2 and 3): Accept SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not App l icab le RECOMMENDATION: Change Note 2 as fo l l ows :

Zln a l l other cases twen t y - f i ve 2 in. x 12 in . cy l inders . . . . sha l l be permi t ted.

Change Note 3 as fo l l ows : 3NS = Non-Spr inklered Space; AS = Spr ink lered Space.

SUBSTANTIATION: Note 2 states: " In a l l cases twen ty - f i ve 2 in. x 12 in . c y l i n d e r s . . . s h a l l be permi t ted. This is a con t rad i c t i on of the previous sentence which states . . . . " ten 2 in . x 12 in. cy l i nde rs .

Note 3 states: "NS : Non-Spr inklered Area; AS = Sp r ink le red . " A s p r i n k l e r covers a space not an area. COMMITTEE ACTION: Accept. COMMITTEE COMMENT: Change to Note 3 withdrawn by Submit ter .

45- 67 - (9-1.5): Accept SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change Section 9-1.5 to agree with the wording of Section 9-1.4 and use the phrase "flammable or combustible materials" in both phrases in this section. SUBSTANTIATION: Confusion could develop when reading Section 9-1.4 and 9-1.5 because of slight word differences namely -- 9-1.4 uses the phrase "flammable or combustible materials"; 9-1.5 uses the phrases "flammable and combustible materials" as well as "combustible dusts and flammable solvents." Also by the use of the word "and" i t tends to imply that both types of hazardous materials need to be present at the same time. This is not true. COMMITTEE ACTION: Accept.

45- 58 - (9-1.6.1): Accept SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Correct the sentence in parentheses at the end of Section 9-1.6.1 to read: "(See Chapter 5 and 9-2.6.3)". SUBSTANTIATION: The reference made at the end of Section g - l .b . l is incorrect and does not agree with the Committee's Draft 3 Text. COMMITTEE ACTION: Accept.

45- 59 - (9-2.3): Hold fo r Further Study SUBMITTER: John M. Galat, West Caldwell, NJ COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add Section 9-2.3.5 to read: 9-2.3.5 Heating equipment used to heat, store or test flammable l iquids or aerosols containing flammable gases shall be designed or modified as fol lows:

(a) Any e lec t r i ca l equipment located within the outer shel l , within the storage compartment, on the door, or on the door frame shaIl meet the requirements for Class I, Division I locations, as described in Ar t i c le 501 of NFPA 70, NATIONAL ELECTRICAL CODE.

(b) Because of hazardous vapors transmitted due to leakage and opening of the storage compartment door, e lec t r i ca l equipment mounted on the outside of the storage compartment shall be ei ther:

( I ) suitable for Class I , Division 2 locations, or (2) instal led above the storage compartment, or (3) instal led on the outside surface of the equipment where

exposure to hazardous concentrations of vapors w i l l be minimal. SUBSTANTIATION: Heating equipment is used for s t a b i l i t y testing of products containing flammable l iquids and aerosols containing flammable gases as propellants. The controls applied to re f r igera t ion and cooling equipment used for storage of flammable l iquids should be applied to heating equipment used for the same purpose. COMMITTEE ACTION: Hold for Further Study. COMMITTEE COMMENT: This proposed revision w i l l require considerable study, Furthermore, i t constitutes new material .

45- 60 - (9-2.3.1): Accept SUBMITTER: Vernon L. Duke, Sandia National Laboratories ~ O N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Before "...overtemperature l imi t swi tch . . . " add mmanual reset." SUBSTANTIATION: Overtemperature l im i t switches should be of manual reset type so that the operators are aware that a temperature excursion occurred. COMMITTEE ACTION: Accept.

45- 61 - (A-3-5.2): Accept SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete Appendix item A-3-5.2. SUBSTANTIATION: This w i l l lead author i t ies having ju r i sd ic t ion to require explosion proof e lec t r i ca l equipment within a certain distance of the f loor in al l chemical labs to be explosion proof, This is not necessary. COMMITTEE ACTION: Accept.

45- 62 - (A-3-5.2): Accept SUBMITTER: George Courtis, Monsanto Research Corp. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: The amounts of flammable l iquids used in laboratory areas and/or units are often very small to require explosion proof e lec t r i ca l equipment near f loor . Also these flammable l iquids are frequently stored in flammable cabinets and they are used under venti Iated areas <hoods, etc). SUBSTANTIATION: No need for explosion-proof e lec t r ica l equipment n e a r - - l a b o r a t o r i e s . COMMITTEE ACTION: Accept. COMMITTEE COMMENT: See Comment 61.

45- 63 - (A-7-2.3.2): Reject SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete A-7-2.3.2. SUBSTANTIATI~: Keeping glass containers of flammable l iquids in metal pai ls is impractical in most laboratories. COMMITTEE ACTION: Reject.

Delete "in metal pai ls or o ther . . . " COMMITTEE COMMENT: The Committee feels that container breakage protection is desireable. The deletion allows more f l e x i b i l i t y in meeting the recommendation, including use of plastic-coated reagent bott les.

45- 64 - (A-7-2.3,2): Reject SUBMITTER: A.J. Pryor, DOE COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete A-7-2.3.2. SUBSTANTIATION: Keeping glass containers of flammable l iquids in metal pails is not considered to be a viable solution to the problem. There are several other far more pract ical and workable solutions to the problem such as protect ive bot t le jackets and p last ic f i lms. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment 63.

45- 65 - (9-2.2 and A-9-2.2): Accept SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change the asterisk from Section 9-2.2 to 9-2.2.2 and change the Section number in Appendix to read "A-9-2.2.2." SUBSTANTIATION: References to this section are not consistent. Section 1-4 Refrigerating Equipment refers to A-9-2.Z; Section 9-2.2* is the asterisked section when i t should have been Section 9-2.2.2* and Appendix A now l i s ts A-g-2.2 d i f f e r ing from the Committee's Draft ~3. COMMITTEE ACTION: Accept.

45- 66 - (A-9-2.2): Accept SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change the words in Section A-9-2.2 to read: "a l l within or exposed to the refr igerated storage compartment."

Change the word " re f r igera t ion" in paragraph 2 of A-9-2.2 to " re f r ige ra to rs . "

Change the number "500" in paragraph 3 of A-g-2.2 to "501," SUBSTANTIATION: The wording in this paragraph that reads "a l l within or exposing the refr igerated storage compartment" is confusing.

Also in the second paragraph of A-9-2.2 the term "laboratory re f r igera t ion" is used where i t more correct ly should be " laboratory re f r ige ra to rs , "

F ina l ly , in the third paragraph of A-9-2.2 the reference to A r t i c le 500 is not as useful as reference to Ar t i c le 501 would be. COMMITTEE ACTION: Accept.

45- b7 - (A-IO-I): Accept SUBMITTER: Noward F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change the last sentence in A-IO-I to read: "Such information should be kept current." SUBSTANTIATION: Appendix items are advisory in nature and therefore word connoting a mandatory requirement should not be used. Section A-IO-I states: "Such information must be kept current." COMMITTEE ACTION: Accept.

45- 68 - (C-2, C-2.2, C-2.3, C-2.4): Accept in Principle SUBMITTER: Vernon L. Duke, Sandia National Laboratories ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: C-2 An explosion is 1) a v io lent bursting, as of a pressurized vessel; or 2) an extremely rapid chemical reaction with the associated production of noise, heat and violent expansion of gasses. Reactive explosions are fur ther categorized as deflagrat ions, detonations and thermal explosions. C-2.2 A def lagrat ion is a rapid combustion or decomposition reaction in which the reaction zone progresses below the speed of sound through the unburned medium. The reaction rate is proportional to the increasing pressure of the reaction. A def lagrat ion may under same conditions accelerate and build into a detonation. The def lagrat ion-to-detonat ion t ransi t ion (D-D-T) is influenced by confinement that allows compression waves to advance and create higher pressures which continue to increase the deflagrat ion rates, This is commonly called "pressure p i l i ng . " C-2.3 A detonation is a rapid combustion reaction which takes place at or above the speed of sound in the unburned medium. A detonation w i l l cause a high pressure shock wave to propogate outwardly, through the a i r , in a l l direct ions at supersonic ve loc i t ies . C-2.a A thermal explosion is a sel f -accelerat ing exothermic decomposition which occurs throughout the ent i re mass (usually solids) with no separate, d is t inc t reaction zone when the rate of energy gain from the decomposition exceeds the energy loss (cooling) from the mass. A thermal explosion may accelerate into a detonation.

The peak pressure and rate of pressure rise in a thermal explosion are d i rec t l y proportional to the amount of material undergoing reaction per unit volume of the container. This is quite unlike gas or vapor explosions, where the loading density is normally f ixed by the combustible mixture at one atmosphere. The Frank-Kamenetsky theory is useful in evaluating the c r i t i c a l mass in the thermal explosion of sol ids. SUBSTANTIATION: To c l a r i f y the def in i t ions. To include in the def in i t ion of explosion reactive explosions that are not enclosed. COMMITTEE ACTION: Accept in Principle.

( I ) Accept verbatim C-2. (2) C-2.2, add "(flame f ron t ) " af ter the words "reaction

zone". Also, the second through last sentences should be designated C-2.2.1.

(3) C-2.3, second sentence should be designated C-2,3.1 arld should read: ".. . through the surrounding environment at ve loc i t ies above the speed of sound."

(4) Revise C-2.4 to read: "A thermal explosion is a sel f -accelerat ing exothermic decomposition which occurs throughout the ent i re mass with no separate, d is t inc t reaction zone." The second sentence w i l l be designated C-2.4.1. The f ina l f u l l paragraph w i l l be designated C-2.4.2. COMMITTEE COMMENT: The changes made are for technical accuracy.

8

45- 69 - (Table C-3.1(b)): Accept SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Change Table C-3.1(b) t i t l e to read: "Criteria for Estimating Missile In jur ies." SUBSTANTIATION: THe t i t l e of this Table gives an indication that the injuries listec wi l l always occur as opposed to the poss ib i l i ty that tF~e injury l isted wi l l occur. COMMITTEE ACTION: Accept.

45- 70 - (C-4.1): Accept SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: A review of the explosion hazard analysis at an appropriate level c f management is recommended. SUBSTANTIATION: Management review of the explosion hazard analysis is recommended. COMMITTEE ACTION: Accept.

45- 71 - (C-4.4): Accept SUBMITTER: Carroll V. Lovett, Easton, CT ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add: " . . . a b i l i t y of the building or room or equipment to withstand the explosion and the cost to restore the f a c i l i t y and equipment..." SUBSTANTIATION: No mention is made about equipment, only f a c i l i t i e s . COMMITTEE ACTION: Accept.

45- 72 - (C-4.5 and C-4.5.3): Accept in Part SUBMITTER: Carrol l V. Lovett, Easton, CT ~ N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Delete the word "recommendations" and insert "items." SUBSTANTIATION: Appendix C is stated as "supplementary information," not recommendations. COMMITTEE ACTION: Accept in Part.

Make change to C-4.5 only COMMITTEE COMMENT: The intent of C-4.5.3 is indeed to o f fe r recommendations.

45- 73 - (C-5.3): Reject SUBMITTER: Howard F. Kempsell, Exxon Research & Engineering Co. COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Elimi~ate Section C-5.3(a) through (g) completely as being redundant.

Add items (h) and ( i ) from C-5.3 to section 5-1.2. Renumber subsequent Sections in Appendix C.

SUBSTANTIATION: Items (a) through (g) are already stated in the body of the standard in section 5-1.2 a lbei t in s l i gh t l y d i f fe ren t order.

Items (h) and ( i ) are not given in the text of 5-1.2. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Appendix C is a supplementary discourse on explosion protect ion. I t is not connected d i rec t l y with 5-1.2.

45- 74 - (C-5-3): Accept in Pr inciple SUBMITTER: Carrol l V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add: "providing explosion venting on equipment." SUBSTANTIATION: No mention is made of explosion venting of equipment. COMMITTEE ACTION: Accept in Pr inciple.

Add to the parenthetical in C-5.3(a): "explosion venting directed to a safe locat ion." COMMITTEE COMMENT: This change para l le ls a simi lar change in 5-1.2(b).

45- 75 - (C-5.4.2): Accept in Principle SUBMITTER: Carrol l V. Lovett, Easton, CT 7~E-N-~-~N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Use another more appropriate term than "non-transparent." SUBSTANTIATION: Corrugated (cardboard) paper, f o i l , etc. are non-transparent and I hope not preferred for explosion shields. Some transparent pl~st ics and glass are designed for high ve loc i ty impacts. The term "non-transparent" is not proper in this context. The next section C-5.4.3 states "Transparent shields are desireable for shields." This is also in con f l i c t with C-5.4.2. COMMITTEE ACTION: Accept in Pr inciple.

Delete f i r s t sentence of C-5.4.2. Revise f i r s t sentence of C-5.4.3 to read: "l~hen transparent shields are necessary fo r viewing purposes, the most common mater ia ls . . . " COMMITTEE COMMENT: The above changes w i l l meet the intent of the Submitter.

45- 76 - (C-5.4.4): Accept SUBMITTER: Vernon L. Duke, Sandia National Laboratories COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Add fol lowing under new heading of C-5.4.4 commercially avai lable explosion shields should be evaluated for the speci f ic hazard. SUBSTANTIATION: None. COMMITTEE ACTION: Accept.

I Designate this new subsection as C-5.4.2 and insert the phrase "against the c r i t e r i a of C-5.4.1" af ter the word "evaluated." COMMITTEE COMMENT: The changes made w i l l enhance the app l i cab i l i t y of the recommendation and provide guidance on evaluation c r i t e r i a .

45- 77 - (C-5.5.1): Accept in Principle SUBMITTER: Carrol l V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Appendix F was not included in the TCR-FSI. SUBSTANTIATION: I could not f ind Appendix F that l i s t s references. How can these be reviewed before voting on this standard? COMMITTEE ACTION: Accept in Principle. COMMITTEE COMMENT: Appendix F is only a l i s t of references included in the text . I t w i l l be a part of the pamphlet edit ion.

45- 78 - (C-5.6.1): Accept in Part SUBMITTER: Carrol l V. Lovett, Easton, CT "C~-I~rE'N-T---~N PROPOSAL NO.: 45-Not Applicable RECOMMENDATION: Revise "Explosion vents should be designed and located so that fragments w i l l not injure occupants in other buildings or areas where personnel may be located." SUBSTANTIATION: How can "must" a mandatory type statement be used in an Appendix? Why is i t a problem i f fragments s t r ike an occupied building without an impact ve loc i ty or does not injure the building occupants. What i f fragments h i t a sol id wall of an occupied building and do no damage. Is this a problem? COMMITTEE ACTION: Accept in Part.

Change "must" to "should." COMMITTEE COMMENT: See Comment 2g.

Correction of Error

An error was discovered in the complete revision of NFPA 45, Standard on Fire Protection for Laboratories Using Chemicals. The fol lowing changes should be made to 8-1.1 of NFPA 45, as printed on page 13 of the 1981 Fall Meeting Technical Committee Reports.

(1) Add an asterisk (*) a f ter 8-1.1. (2) Delete "Compressed Gas Association (CGA)." (3) Delete items (g) and (k); renumber accordingly. (4) Add Appendix item A-8-1.1 to read: "For additional

information, see Compressed Gas Association Pamphlet P-l , Safe Handling of Compressed Gases in Containers, and National Safety Council Data Sheet 1-688-80, Cryogenic Fluid in the Laboratory."

PART 11

496- 1 - (1-1.1): Accept in Principle SUBMITTER: Charles G. Heisig, Sybron-Taylor Instrument Co. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Change the wording of 1-1.1 to: "This standard shall apply to the design of purged enclosures for e lec t r i ca l equipment which do not contain an internal source of flammable gases or vapors and which are" located in areas c lass i f ied by a r t i c l e 500 of NFPA 70, NATIONAL ELECTRICAL CODE. (This w i l l l im i t the use of NFPA 496 to si tuations in which i t w i l l be safe.) SUBSTANTIATION: The standard as wri t ten w i l l not prevent formation of flammable mixture inside of an enclosure i f the enclosure is separated from process f lu id (flammable) by a single (leaking) seal. This is especial ly true for process analyzers operating on l iquid hydrocarbon streams. The pressure of the process f lu id w i l l almost always exceed 0 . i in. W.G, and therefore w i l l leak into the enclosure. This is the si tuat ion exist ing under the last paragraph of NFPA 70 500-4(b). This problem is being addressed by IEC 79-2 draf t now being circulated. COMMITTEE ACTION: Accept in Pr inciple.

Add I-1.3 to read: "This standard shall not apply to enclosures in which a flammable material is introduced, such as gas chromatographs or gas analyzers." COMMITTEE COMMENT: The proposed addition w i l l more c lear ly state where 496 does not apply. The si tuat ion described by the Submitter has not yet been considered by the Technical Committee, but w i l l be discussed at the i r next meeting.

9

496- 2 - (1-5): Accept SUBMITTER: Bruce D. Gibson, Taylor Instrument Co. COMMENT ON PROPOSAL NO.: 496-i RECOMMENDATION: Change "Ar t ic le 500-2(a)" to read: "Ar t ic le 500-4(a)." SUBSTANTIATION: Last sentence (Parenthetical Note) of de f in i t ion of Class 1 Division I Location refers to the wrong Ar t i c le of NFPA 70, NATIONAL ELECTRICAL CODE. COMMITTEE ACTION: Accept.

496- 3 - (1-5): Accept SUBMITTER: Charles G. Heisig, Sybron-Taylor Instrument Co. COMMENT ON PROPOSAL NO.: 496-Not Applicable. RECOMMENDATION: Use f u l l text of NFPA 70, Section 500-4(b).

Al ternat ive. A more re l iab le method of having def in i t ions on NFPA 496 agree with NFPA 70 is simply to d i rec t l y reference the la t te r without attempting to include the entire text . SUBSTANTIATION: The ent i re last paragraph of NFPA 70 500-4(b) is missing from def in i t ion of Class I , Division 2.

Electr ical conduits and thei r associated enclosures separated from process f lu ids by a single seal or barr ier shall be classed as a Division 2 location i f the outside of the conduit and enclosures is a nonhazardous location. COMMITTEE ACTION: Accept.

496- 4 - (2-2.1.2 (New)): Accept SUBMITTER: Charles G. Heisig, Sybron-Taylor Instrument Co. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Add wording of 5-2.1.2 to Chapter 2 as 2-2.1.2. SUBSTANTIATION: Spark Suppressors are required in Class I I locations: Section 5-2.1.2 but not in Class I locations. This does not seem logical .

The fol lowing non-USA codes recommend or require spark suppressors in Class I locations:

EN50016 / BS 5501 pt. 3 (1977) IEC 7g-2 (1975) Draft IEC 79-2

COMMITTEE ACTION: Accept.

496- 5 - (2-2.3): Reject SUBMITTER: L l l i o t Rappaport, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Delete Section 2-2.3. SUBSTANTIATION: According to the Scope (1-1.2), th is is a design standard. Therefore, th is standard cannot require speci f ic operating procedures af ter the equipment is insta l led. I f the indicated procedure is necessary, then the design should include specif ic sensing and/or interlocks that would insure the indicated procedure. COMMITTEE ACTION: Reject.

Delete "the design at" in i - I . I . Also, add "and the necessary associated safety measures" af ter the word "enclosures" in l ine two of 1-2. COMMITTEE COMMENT: The changes made c l a r i f y the intent of the ~ e that ~ 6 address i n i t i a l design and subsequent operation.

496- 6 - (2-2.3.1): Reject SUBMITTER: E l l i o t Rappaport, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Delete the f i r s t part of the f i r s t sentence to the comma. The paragraph should read: "Posit ive pressure shall be maintained within the enclosure. No speci f ic f low rate need be maintained." SUBSTANTIATION: This is a design standard and therefore should not require specif ic operating procedures af ter the equipment is insta l led. The requirement for posi t ive pressure and flow rate is independent of a previous fa i l u re . COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The current wording emphasizes the proper sequence of actions.

496- 7 - (2-2.4): Reject SUBMITTER: Charles G. Heisig, Sybron-Taylor Instrument Co. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Add the fol lowing as 2-2.4.1: 2-2.4.1 Each e lec t r i ca l conduit attached to the purged enclosure shall be subject to the fol lowing conditions:

(a) The internal free volume of the conduit between conduit seal and the purged enclosure shall not exceed I percent of the net (minimum) free volume of the enclosure.

(b) No normally operating igni t ion sources shall be in close proximlty to the conduit opening.

(c) The purge vent shall be remote from the conduit opening.

SUBSTANTIATION: The volume of the e lec t r i ca l conduit between i ts point of attachment to the enclosure and the conduit seal cannot be treated as required by 2-2.4. Some l im i t should be placed on the length of this conduit.

The approved explosion proof conduit seals, commonly used to retain the purge pressure within the enclosure, are only rare ly leak t ight so the volume of the conduit is e f fec t i ve l y purged in actual operation. Limiting the net volume of the conduit between the purged enclosure and the seal should prevent the formation of any s ign i f icant amount of flammable mixture inside of the enclosure even i f the conduit stub has been f i l l e d with IOU percent flammable gas/vapor.

Isolat ing the conduit opening from any normally operating igni t ion sources and purge vent minimize the probabi l i ty of igni t ion of any flammable mixture that might form at the conduit opening and fur ther minimize the propagation of any igni t ion outside of the enclosure. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Conduit seals are sometimes used so that the conduit can be u t i l i zed as a means of leading purge gas to the enclosure. I f a seal is used, the conduit w i l l be pressurizea on the enclosure side of the seal. I f not used, the conduit w i l l have to be pressurized anyway.

496- 8 - (2-3.3.1): Reject SUBMITTER: E l l i o t Rappaport, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Change to read: "The alarm shall be located at a constantly attended locat ion." SUBSTANTIATION: For safe operation, i t is desirable that any abnormal operation be ident i f ied before the condition escalates to a hazardous condition. The above is cer ta in ly true for Type X purging and may also be true for Type Z purging where the abnormal operation is a result of a condition that also introduces igni table concentrations of flammable gases or vapors into the enclosure. Use of an alarm that is readi ly seen or heard does not imply that i t w i l l be ident i f ied since there may not be anyone around to hear or see the alarm. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee feels that 2-3.3.1 adequately addresses the issue.

496- 9 - (2-3.4. 2-3.4.1, 2-5.7, 2-5.7.1, 4-2.8, 4-2.8.1): Hold for Further Study SUBMITTER: Charles G. Heisig, Sybron-Taylor Instrument Co. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Insert the fol lowing af ter 2-2.3.1 as 2-2.4 and renumber present 2-2.4 and fol lowing items: 2-2.4 A caution label shall be permanently attached to the enclosure so that i t is v is ib le before the enclosure can be opened. 2-2.4.1 The purge conditions necessary to pass at least four enclosure volumes of purge gas through the enclosure shall be determined. 2-2.4.2 The caution label shall contain the fol lowing or equivalent statement: "Caution: Enclosure shall not be opened unless the area is known to be nonhazardous or al l devices within have been de-energized. Power shall not be applied unt i l the enclosure has been properly closed and purged for minutes at SCFH."

E ~ a t e 2-3.4, 2-3.4.1, 2-5.7, 2-5.7.1; 4-2.8, 4-2.8.1 and renumber remainder. SUBSTANTIATION: 1. The text of 2-3.4, 2-3.4.1 are repeated as 2-5.7, 2-5.7.1 and 4-2.8, 4-2.8.1.

2. Purge conditions are time of purging and purge gas flow rate. 3. No purpose is served i f these are merely calculated. The

conditions must be on the label attached to the equipment. 4. The label does not require the operator to close the door of

the equipment before purging, etc. 5. I n i t i a l start-up is not covered by the wording of the label

of 2-3.4 etc. COMMITTEE ACTION: Hold for Further Study.

Change 2-3.4.1 and 2-5.7.1 to read: "The manufacturer shall recommend purge conditions and f low rate necessary to pass at least four enclosure volumes of purge gas in the time period specif ied on the label ."

Change 4-2.8.1 to read: "The manufacture shall recommend purge conditions and f low rate necessary to pass at least 10 enclosure volumes of purge gas in the time period specif ied on the label. COMMITTEE COMMENT: The changes made actual ly revert back to the intent of the 1974 edi t ion. This c l a r i f i e s that the necessary purge conditions are determined by the manufacturer. Any fur ther changes are not warranted unt i l the subject is reviewed by the f u l l Committee.

496- 10 - (2-4.2.3): Reject SOBMITTER: E l l i o t Rappapert, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Reword last sentence to read: "Such precautions shall include overcurrent and ground fau l t protection for such wiring in conjunction with enclosure thickness and mater ia l . "

10

SUBSTANTIATION: lhe hazard of a fau l t is that an arc w i l l occur rather than a solid fau l t connection. A solid fau l t (short c i r cu i t ) to grounc should produce su f f i c ien t fau l t current ( i f grounded properly) to open the overcurrent device. An arcing fau l t may cause extensive damage, raise the internal temperature to near arc temperature, and yet not result in su f f i c ien t current to open the overcLrrent device. The only protection for this hazard is a grounc fau l t protect ive device. The hazard on 277 vol t to ground systems is especial ly great because the arc voltage of approximately 100 volts does not extinguish the arc. On 120 vo l t to ground systems, the arc may be se l f extinguishing. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The wording of 2-4.2.3 does not mandate any par t icu lar means cf compliance. The intent was to maintain f l e x i b i l i t y . The Submitter's proposal would allow only one means of compliance and i t is uncertain i t would accomplish the object ive. The Technical Committee w i l l discuss this issue in detai l for the next edi t ion.

496-. 16 - (A-1-1.1): Hold for Further Study SUBMITTER: Charles G. Heisig, Sybron-Taylor Instrument Co.

ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Add fol lowing sentence to A-1-1.1: "Refer to draf t of new IEC 79-2 proposed standard for guidance for purging enclosures containing internal sources of flammable gases and vapors." SUBSTANTIATION: Restr ict ing app l i cab i l i t y of NFPA 496 to enclosures not containing an internal source of flammable gases/vapors eliminates a l l standards, guidelines, etc. for purging equipment such as process analyzers which include such sources. COMMITTEE ACTION: Hold for Further Study. COMMITTEE COMMENT: The Committee feels that i t would be premature to reference a document which has not had fu l l committee review.

496- 11 - (2-4.3): Reject SUBMITTER: E l l i o t Rappaport, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: [elete 2-4.3. SUBSTANTIATION: lhe wording of the paragraph is such that i f 2-4.2 is met, UL listing of equipment meeting Division 2 requirements is nct necessary. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Subsection 2-4.3 does not require UL listing. There is no intent to require UL listing in any NFPA standard.

496- 12 - (3-2 (New)): Reject SUBMITTER: E l l i o t Rappaport, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: A ~ w Section 3-2.3. 3-2.3 Where flammable gases or vapors at pressures in excess of 25 Pascals are contained in the control room in any manner, an instrument that detects gas concentration shall be insta l led. The detection device shall provide an audible alarm in a constantly attended location. SUBSTANTIATION: Provision of a posi t ive pressure in a control room is not su f f i c ien t to insure non-hazardous operation especial ly i f piping or equipment containing or carrying flammable gases or vapors at pressures in excess of 25 Pascals are present in the control room. A means of detecting the presence of an ignitable concentration is v i t a l in that case. COMMITTEE ACTION: Reject. COMMITTEE COMNENT: This is outside the scope of NFPA 496. See Comment 1.

496- 13 - (3-3.3): Reject SUBMITTER: E l l i o t Rappaport, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Ac]~-a-a-{ter "a i r system" the fol lowing: "or gas concentration detection alarm." SUBSTANTIATION: See discussion for new Section 3-2.3. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment 1.

496- 14 - (3-3.4): Reject SUBMITTER: E l l i o t Rappaport, Smith, Hinchman & Gryl ls Associates, Inc. COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: AcT~-~tween "failure" and "shall" the following: "or gas concentration detection alarm." SUBSTANTIATION: See discussion for new Section 3-2.3. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Comment I.

496- 15 - (4-2.5, 3-3.8, and 2-4.2.3, 2-5.5.2): Accept SUBMITTER: George H. St. Onge, American Petroleum Ins t i tu te COMMENT ON PROPOSAL NO.: 496-Not Applicable RECOMMENDATION: Add fol lowing introductory phrases: 4-2.5 "For Type Z purg ing, . . . " 4-3.8 "For equipment in Division 2 loca t ions . . . " SUBSTANTIATION: 4-2.5 and 4-3.8 contain an exception which permits surface or egress a i r temperature above 80 percent of the auto- igni t ion temperature of the gas or vapor involved i f tests show that the excess temperature w i l l not ignite the gas or vapor involved. No l imi ta t ion is placed on the type purging (X, Y, or Z) or i f the equipment venti lated is in a Division I location.

This does not seem to be consistent with 2-4.2.3 and 2-5.5.2 which permit no exception on enclosure surface temperatures in Division I locations (Types Y and Z) or with the pr inc ip le contained in NFPA 70 Section 501-8(a). COMMITTEE ACTION: Accept.

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