Report of the Committee on

Building Construction

PeterJ. Gore Willse, Chair HSB Industrial Risk Insurers, CT [I]

Robert M. Berhinig, Underwriters Laboratories Inc., IL [RT] Brenda L Bronson, U.S. General Services Administration, CO [U] Richard J. Corcoviios, West Virginia state Fire Marshal, WV [E]

Rep. Fire Marshals Assn. of North America Richard J° Davis, Factory Mutual Research Corp., MA [I] Alan J. Dopart, Willis Corroou Corp., NJ [I] Bruce A. Edwards, Wansau HPR Engr, MA [I]

Rep. The Alliance of American Insurers Sam W. Francis, American Forest & Paper Assn., PA [M] Daniel F. Gemeny, RolfJensen & Assoc., Inc., CA [SE] Richard G. Gewain, Hughes Assoc., Inc., MD [SE] Karl D. Houser, Gypsum Assn., DC [M] Harlan C. Ihlenfeldt, Kemper Nat'l. Insurance Cos., IL [I] Gerald KeUiher, Westinghouse Savannah River Co., SC [LI] TimothyJ. Matey, Entergy Operations Inc., LA [U] Joseph J. Messersmith, Jr., Portland Cement Axsn., VA [M] John D. Nicholas, ARCON Int'l, Inc., GA [SE] Brad Schiller, Brad Schiffer/Taxis, Inc., FL [SE] Raymond S. Szczucki, CIGNA Loss Control Services, PA [I]

Rep. American Insurance Services Group, Inc Lyndon Welch, Ann Arbor, MI [SE] Robert J. Wills, American Iron & Steel Inst., AL [M]

Alternates

J e s ~ J . Beitel, Hughes Assoc., Inc., MD [SE] (Alt. to R. G. Gewaln)

Kenneth E. Bland, American Forest & Paper Assn., DC [M] (Alt. to S. W. Francis)

David W. Frable, U.S. General Services Administration, IL [U] (Alt. to B. L. Bronson)

Alfred J. Hogan, Reedy Creek Improvement District, FL [E] (Alt. to R.J. Corcovilos)

Robert Martinelli, Kemper Nat'l Insurance Cos., MA [I] (Alt. to H. C. lhlerffeldt)

Todd E. Schumann, HSB Industrial Risk Insurers, IL [I] (Alt. to P . J .G . Willse)

Stephen V. Skalko, Portland Cement Assn., GA [M] (Alt. to J. J. Messersmith, Jr.)

staff Liaison: Robert E. Solomon

Committee Scope: This Committee shall have primary responsibility for documents on the design, installation, and maintenance of building construction features not covered by other NF~A committees. This Committee does not cover building code requirements, exits, protection at openings, vaults, air conditioning, blower systems, etc., which are handled by other committees.

This list represents the rm.'mbership at the t~nw the Committ,~'e was balloted on the text of this edition. Since that tirlw, changea in tl, membership may have occurred. A ke~ to class~ficatio'ns is jo~znd at th~ ]font of this book.

The Report of tbe Technical Committee on Building Construction is presented for adoption.

This Report was prepared by the Technical Committee on Building Construction mad proposes for adoption amendments to NFPA 220-1995, Standard on Types of Building Construction. NFPA 220-1995 is published in Volume 5 of the 1998 National Fire Codes and in separate pamphlet form.

This Report has been submitted to letter ballot of the Technical Committee on Building Construction, which consists of 20 voting members. The results of the balloting, after circulation of any negative votes, can be found in the report.

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N ~ A 2 2 0 1 A 9 9 R O P

(Log #1) 220- 1 - (Chapter 1): Reject Note: Tiffs Proposal appeared as Conunent 220-1 which was held

from the Annual 95 ROC on Proposal 220-10. SUBMITTER: Dick Davis, Factory Mutual Research RECOMMENDATION: A. Add the following alternative definition to Chapter 1 for Limited-Combustible Material:

" o r , 2. The average peak rate of heat release shall not exceed 60

kW/m 2 and the average total heat release shall not exceed 20 m J / m 2, when tested in accordance with NFPA 264,1, Standard Method of Test for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen Consumption Calorimeter."

Add the following alternative definition to Chapter 1 for Noncombustible Material:

"or~ 2. The average peak rate of heat release shall not exceed 45

kW/m 2 and the average total heat release shall not exceed 15 m J / m 2 when tested in accordance with NFPA 2641. Sustained flaming on or over the surface of the specimen shall be less than 4 sec. Mass loss of ,all specimens shall be less than 50 percent."

B. Add the following footnote to the end of Chapter 1: "Footnote 1: Tbe following test criteria shall be incorporated

when using NFPA 264 to classify a material: (a) Ignition shall be piloted. (b) The effective area (As) used to determine the heat release

rate shall be 0.0088 m2. (c) The exposure heat flux shall be 60 kW/m2. (d) The data recording interval shall be 2 sec. (e) For variable thicknesses _< 2 in., the min imum and

maximum thickness shall be tested. (f) The duradon of the test shall be 15 min plus the length of

the instrument delay time. (g) The exposed surface of the test samples shall be blackened

use a single layer coating with a min imum absorptivity of 0.95. (h) NFPA 264 shall not be used to classify multi-layer products

composed of dissimilar materials." C. Add the following to the Appendix: A-1 The Peak Rate of Heat Release (PRHR) may be plotted

versus the respective Exposure Heat Flux (EHF) to estimate the potential for a self-propagating fire with a material. The slope of the best fit line is defined as the Heat Release Parameter (HRP). The material may be considered to be of limited-combustibility when HRP does not exceed 4. The following equation summarizes this for materials of limited - combustibility:

HRP = ~PRHR _< 4 AEHF

SUBSTANTIATION: A. Alternative test methods are needed to classify material in light of the limitations of existing listed tests. NFPA 264 is believed to be tile most realistic small scale test for this purpose.

B. Blackening of tile specimen surface in file NFPA 264 test allows for standardization and consistency of the test. Other criteria is not currently covered in NFPA 264 either and is necessary to aclfieve realistic and consistent test results. The current value o fA s (0.01 m 2 does not reflect die 94 by 94 mm opening widtiu the non-insulating edge ti'ame.

C. Studies by Factory Mutual Research Corporation confirm the above. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: While die proposal attempts to update some methods that are being considered for further defining and describing a set of specific values for defining non- combustible and limited combustible materials, the committee does not want to move forward with those changes at this timeo Tile concerns are:

- There does not appear to be widespread agreement to state emphatically that the cone calorimeter is the most accurate apparatus for this procedure.

- A change at this point i spremature . While work continue in this area, nothing has been finalized with respect to the best or preferred method of determining the pass-fail criteria, nor the accuracy of file apparatus used to evaluate the materials.

- The sample preparation t edmique to allow for blackening of the material surface is difficult to reproduce. Using a stove paint is difficult since tile paint incorporates some flammable liquid component . This results in some flaming and burning which can cause an error in the final analysis. Using a carbon black

substance is difficult since it is likely to disperse while tile sample is being moved from the preparation area to the test apparatus. This also may lead to a sensitivity from the product nl~umfacnn-et being concerned with the physical change to die surface of the material being tested.

The committee believes that this change would be prematnrt- at tiffs point. If accepted, NFPA 220 may be back to reverdtJg to 1995 text, or referencing another test method in the next edition. This would be unfair to authorities having jurisdiction, manufacturers and designers who would have to refer to another set of pass-fail criteria. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITI'EE ACTION:

AFFIRMATIVE: 18 NOT RETURNED: 2 Matey, Nicholas

(Log #CPI) 220- 2 - (1-2): Accept SUBMITI'ER: Technical Committee on Building Construction RECOMMENDATION: Add a new paragraph to indicate the allowance for equivalency methods and approaches in NFPA 220 as follows:

1-2 Purpose. 1-2.2 This standard provides definitions for standard types of

building construction. 1-2.2 Nothing in this standard is intended to prevent the use of

alternate mater-ials or devices, provided sufficient technical data is submitted to the authoritv havin~ Jurisdiction to demonstrate that the alternate method of construction or device nrovides equivalent stren~,th mid fire resistance. SUBSTANTIATION: The addition of tile equivalency sKtteineut will permit other options to be used when trying to sadsfy die provisions of NFPA 220. Other methods and test standards can now be utilized and accepted if they achieve the same end resuh that is contemplated by NFPA 220. COMMI3ffrEE ACTION: Accept. NUMBER OF COMMITrEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 18 NOT RETURNED: 2 Matey, Nicholas

(Log #CP3) 220- 3 - (l-S): Accept SUBMITTER: Technical Committee on Building Construction RECOMMENDATION: Revise file text of Section 1-3 ,as shown below:

1-3 Guide to Classification of Types of Building Construction. The types of construction include five basic types designated by Roman numerals as Type I, Type II, Type III, Type IV, and Type V. This system of designating types of construction also includes a specific breakdown of the types of construction through the use of Arabic numbers. These numbers follow the Roman numeral notation where identifying a t~qge of construction (e.g., Type 1-443, Type II-111, Type III-200).

rcq'dlrcmcn'~ for ccr'^..2n :'~--act'.:ral clemcnt~ ~ f~!Ic:'.~: / - - \ E ~ . _ . . A o ~ k : _ K t . . _ _ k ^ _ . 1~ . . . . . : - - " "~- :~g ;vall¢. [t.~ c . . . . .~ A..k:~ Number: Ca!u..'~.nc, . . . . . . . , ~ . . . . . . ,

. . . . - . . . . . , o~vv . . . . . . e, . . . . . . . r:, . . . . . . , . . . . . . . . . . , or ...... g from

Specific fire resistance requirements are found in Table 3-1. Add die strike througb text to a new appendix section :Ls follows: A-l-3. The .Arabic numbers followin~ each basic tvoe of

construction (e.g.. Tvoe I. Tvoe II) indicate the fire resistance ratin~ reauirements for cert,ain structural elements as follows:

(a) First Arabic Number: Exterior bearing walls. fb/ Second Arabic Number: Columns. beams, eirders, trusses

and arches, support in~ bearing walls, columns, or loads from more than one floor.

(c) Third Arabic Number: Floor construction. SUBSTANTIATION: Some users of NFPA 220 have found the text in Section 1-3 to be somewhat confusing and difficult to enforce. As an example, fire item (b) text has lead some to interpret this as meaning that no other ratings, other than what is shown in the second row of NFPA 220, Table 3-1 are permitted for

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N F P A 2 2 0 - - A 9 9 R O P

a given construct ion type. This was never the in ten t of this langnage. Dur ing a review of this section, the commi t tee has de t e rmined tha t the text which is now being placed in the append ix is really instruct ional informat ion and shon ld not be in the main body of the s tandard. COMMITTEE ACTION: Accept . , , NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITT E E ACTION:

AFFIRMATIVE: 18 NOT RETURNED: 2 Matey, Nicholas

(Log #2) 220- 4 - (Chapter 2): Reject Note: Th i s Proposal appea red as C o m m e n t 220-6 which was he ld

f rom the Annua l 95 ROC on Proposal 220-10. SUBMITTER: Rick Thornberry , W.R. Grace RECOMMENDATION: Accept the proposal as modif ied in accordance with tile following:

Limited-Combust ib le Material. A bui ld ing construct ion material not complying with the defini t ion of noncombus t ib le material that, in tile form in which it is used, is a material that conforms to artS, eifller one of the following conditions:

1. Has a potential hea t value no t exceeding 3,500 Btu per Ib (8141 kJ/Kg), when tested in accordance with NFPA 259, Standard Test Method for Potential Heat of Bnildlng Materials, and complies with one of tile following paragraphs (a) or (b).

(a) Materials having a structural base of noncombus t ib le material; with a snrfacing no t exceeding a thickness of 1 / 8 in. (3.2 mm) that has a f lame spread rating not greater than 50.

(b) Materials, in the form and thickness nsed, t r i te r tban as described in (a), having ne i ther a f lame spread rat ing greater than 25 nor evidence of con t inued progressive combus t ion and of such composi t ion that surfaces tha t would be exposed by cut t ing th rough tile material on any plane would have ne i ther a f lame spread rating greater than 25 nor evidence of cont inued progressive combus t ion .

2. Has an average peak rate of hea t release not exceeding ~2-~89_0

k W / m 2 and an average total hea t release not exceeding 20 m J / m 2 when tested in accordance with NFPA 264, Standard Method of Tes t for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen C o n s u m p t i o n Calorimeter , l~;rizc,~t:;l o:'~enmt!o~ at a hea t ing flux of 75 ~ k W / m 2 for a dura t ion o f / O 1 5 rain after the delay t ime of tile apparatus. Susut ined f laming shall no t occur and tile mass loss shall no t e ~ e c d 50 percent .

Materials subject to increase in combustibil i ty or f lame spread rat ing beyond the limits here in established th rough the effects of age, moisture , or o ther a tmospher ic condi t ion shall no t be def ined as l imited combust ible . S U B S T A N T I A T I O N : Based on o n g o i n g studies by tile CABO Board for Coord ina t ion of tile Model Codes (BCMC) and tile NFPA 220 Noncombus t ib l e /L imi t ed -Combus t ib l e Task Force, addit ional informat ion and data have been developed which tend to indicate tha t this proposal as modif ied Should be an acceptable :dternate me thodo logy for de t e rmin ing tile l imited-combustibili ty of bui ld ing construct ion materials. The decrease indicated for the peak rate of hea t release is i n t ended to be more conservative yet still allow T e c t u m (a wood f i b e r / c e m e n t composi te material) to qualify as l imited-combnst ible .

This proposal is based on tile a s sumpt ion that the following test condi t ions will be inc lnded in the proposed 1995 edit ion of NFPA 264 which is being processed s imul taneously with this s tandard:

1. a spark igniter will be used, 2. the edge f rame spec imen holder will be used with an exposed

spec imen area of 0.0088 m 2, and 3. the data recording interval will no t exceed 2 sec. If these revisions are no t made to NFPA 264, then they mus t be

incorpora ted into this proposal should it be accepted by the Commit tee . COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See the Commit tee Action on 220-1 (Log #1). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 18 NOT RETURNED: 2 Matey, Nicholas

(Log #3) 220- 5 - (Chapter 2): Reject Note: This Proposal appea red as C o m m e n t 220-7 which was held

f rom the Annua l 95 ROC on Proposal 220-13. SUBMITTER: Rick Thornber ry , W.tL Grace RECOMMENDATION: Accept the proposal as modif ied in accordance with the following:

Noncombus t ib le Material. A bui ld ing cons t ruc t ion material that, in the form in which it is used and u n d e r the condit ions anticipated, will no t ignite, bnrn, snppor t combus t ion , or release f lammable vapors, when subjected to fire or heat. Materials that conform to e i ther one of the following test condi t ions shall be cons idered noncombus t ib l e materials:

1. Materials repor ted as passing ASTM E136, S tandard Test . Method for Behavior of Materials in a Vertical Tube Furnace at 750°C, o.._r,r

2. Materials having an average peak rate of heat release not exceeding -1-~ 20 k W / m 2 and an average total hea t release not

exceeding ~10 m J / m 2 when tested in accordance with NFPA 264, S tandard Method of Test for Heat and Visible Smoke Release Rates for Materials and Products Using an ()xygen Consumpt ion Calorimeter, ".:~ing t!~'c !:~r:.z'~:;m, t -~ri,c:~tz:tk,;:: at a beating flux ot not less than 75 k W / m 2 _+-6 for a durat ion of 4-9- j..55 rain :diet the delay t ime of the apparatus . Sustained f laming shall not ~c~ut ~u~d the mass loss shall no~ exceed 50 nercent .

Materials subject to increase in combustibili ty beyond the limiLs here in established th rough the effects of age, moisture, or other a tmospher ic condi t ion shall no t be considered noncombus t ib le materials. S U B S T A N T I A T I O N : Based on o n g o i n g studies by the (2ABO Board for Coord ina t ion of tile Model (;odes (BCMC) and the NFPA 220 Noncombus t i b l e /L imi t ed -Combus t i b l e Task Force, addit ional in format ion and data have been developed which tend to indicate that this proposal as modif ied should be an acceptable al ternate me thodo logy for de t e rmin ing the noncombust ibi l i ty of bui lding construct ion materials. The increase indicated for the peak rate of beat release is in tended to accommoda te in s t rumen t "noise" and exper imenta l variability at snch a low value. The increase indicated for the total hea t release also reflects a 50 percent increase in the dura t ion of the test.

This proposal is based on the assumpt ion that the following test condi t ions will be inc luded in the p roposed 1995 edit ion of NFPA 264 which is being processed s imul taneous ly with this s tandard:

1. a spark igniter will be nsed, 2. the edge f rame spec imen holder will be nsed with an exposed

spec imen area of 0.0088 m 2, and B. tile data recording interval will no t exceed 2 sec. If these revisions are no t made to NFPA 264, then they m u s t be

incorpora ted into this proposal should it be accepted by the Commit tee . COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See the Commit tee Action on 220-1 (Log #1). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 2O VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 18 NOT RETURNED: 2 Matey, Nicholas

(Log #4) 220- 6 - (Chapter 2): Accept in Principle Note: This Proposal appeared ,as C o m m e n t 220-8 which was held

f rom the Annual 95 ROC on Proposal 220-10. SUBMITTER: Frederic B. Clarke, E.I. du Pont de Ne m o u r s & Co, Inc. RECOMMENDATION: Delete proposed changes; text to remain as in NFPA 220-1992. S U B S T A N T I A T I O N : The use of NFPA 264, the cone calorimeter , as an al ternate m e t h o d of def in ing the term "limited combust ible" would be a potential redtlction in the level of protect ion afforded by the s tandard. There are three reasons wby this is so.

1. Tile existing test provides an uppe r limit of hea t produced; the proposed new test does not. The test on which the defini t ion of l imited combust ib le is now based, NFPA 259, S tandard Method for the Potential Heat of Building Materials, measures the total a m o n n t of heat a given quant i ty can produce on burn ing . The p roposed al ternate, NFPA 264, measures bu t a fract ion of this total. Of part icular concern is tha t the measured fraction is no t a cons tant but varies accord ing to the material (see Exhibit 1). Since NFPA 264 does not s imulate the most severe physical (see reason #2 below) or thermal condi t ions to which the material can

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N F P A 2 2 0 - - A 9 9 R O P

be exposed,- in practice one has no way of knowing whether it will release more heat , less heat, or the same a m o u n t in an actual fire. By contrast, we know tha t materials tested by NFPA 259 will p roduce no more , and usually less, hea t u n d e r fire condi t ions than in the test. This is the more conservative and, in my view, the more appropr ia te posture .

Since the potential hea t de t e rmi ned by NFPA 259 is essentially a t he rmodynamic quant i ty it is very difficult to envision env i ronmenta l condi t ions u n d e r which it would increase due to die effects of age, mois ture or a tmospher i c condit ions. Hence a "limited combust ible" u n d e r the cu r ren t test virtually canno t become "combust ible" material ,after is installed. This is no t the case with materials tested u n d e r NFPA 264, where fire retardants, for example , can effect both the hea t release rate and the total hea t released. Subsequen t env i ronmenta l leaching or segregat ion of the fire re ta rdant can result in a substantially different, and considerably more combust ible , material . In such cases, NFPA 259 would no t have permi t ted use of the FR material in the first place, so any t rans ient effects FR are a moo t point.

2. Samples which char or exhibi t similar protective surface effects can do m u c h better in the proposed test t han in a fire. NFPA 264 calls for the m e a s u r e m e n t of hea t release f rom a horizontal ly-supported, und i s tu rbed sample° Radiant energy is supplies f rom above. In this configurat ion, any protective effects f rom the sample ' s surface, such as refractory behavior or the insulat ion of u n b u r n e d sample by char or ash, are fully realized. In actual use, the sample may be installed vertically, or even facing downward, and du r i ng the course of a fire it is likely to be physically disturbed. All of these are th ings can reduce the efficacy of surface protective effects. Hence , adopt ion o f NFPA 264 as an al ternate to NFPA 259 reduces one 's conf idence tha t test results reflect, or at least consti tute the bounda ry of, real behavior°

3. The p roposed new test is no t readily applicable to materials without a f ixed surface-to-thickness ratio. For example , a bed of wire or cable (c.f. NFPA 90A) may pass the p roposed limit if it is one wire deep, as is the normal test conf igurat ion for NFPA 264, but beds two or more wires deep, which are more typical of actual bui ld ing installations, would fail to mee t the l imitation on total hea t release. The same difficulty applies to some degree to odter products , such as applied-in-place nnsulatlon, where die installed thickness is not , and canno t be, closely controlled. COMMITTEE ACTION: Accept in Principle.

No fur ther change to the text is needed. COMMITTEE STATEMENT: The text originally proposed for the 1995 edi t ion of NFPA 220 with respect to limited combust ible materials did not change. While research and work in this a rea cont inues and is underway, the commi t tee is no t of the opin ion that the status of this work is at the point where addit ional changes to NFPA 220 are in order. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 17 ABSTENTION: 1 NOT RETURNED: 2 Matey, Nicholas

EXPLANATION OF ABSTENTION: HOUSER: I did no t have the benefi t of the Commit tee ' s

discussion per ta in ing to Dr. Clarke's compar i son of the effective hea t of combus t ion obta ined by NFPA 264 (the cone calorimeter) and potential hea t values derived f rom NFPA 259 (the oxygen b o m b calor imeter ) .

(Log #5) 220- 7 - (Chapter 2): Reject Note: This Proposal appea red as C o m m e n t 220-9 which was held

f rom the Annua l 95 ROC on Proposal 220-1g. SUBMITTER: Frederic B. Clarke, E.I. du Pont de Nem o u r s & Co, Inc. RECOMMENDATION: Accept the submit ter ' s language for defini t ion of Noncombus t ib le material t h rough paragraph "1"~

In place of submit ter ' s paragraph "2", subst i tute new text: ~. has a notential hea t value not exceedin~ 860 Btu her Ib (2000

k_I/kg), when tested in accordance with NFPA 259. Standard Test Method for Potential Heat of Building Materials.

Accept the submit ter ' s language for the third paragraph. S U B S T A N T I A T I O N : This proposal allows use of the same me thod , but with different criteria, for both noncombus t ib les and l imited combustibles, The choice of 860 B t u / l b reflects the in tent of ASTM 136 to classify as noncombus t ib l e materials having up to abou t 3 p e r c e n t of combust ib le content . The reasons against us ing NFPA 264 to def ine noncombust ib i l i ty are the same as those detai led in my c o m m e n t on proposal 220-10. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: The commit tee is of the opinion that the sample size used in NFPA 259 is no t representat ive of what the commit tee expects would replicate how the material would behave in an actual fire. A material tha t had a potential heat value as low as 860 B t u / l b would likely no t even be a candidate for this test.

In addit ion, the commit tee does no t see how a result derived with NFPA 259 for this de te rmina t ion would be different e n o u g h f rom an ASTM E-136 test result. Both test protocols would produce similar or parallel informat ion. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 18 N O T RETURNED: 2 Matey, Nicholas

(Log #CP2) 220- 8 - (2-1 Approved, Author i ty Having Jurisdict ion, Listed, Shall, Should) : Accept SUBMITTER: Technica l Commi t t ee on Building Cnnsu-ucnion~ RECOMMENDATION: Add tile following definitions, includin~ related append ix informat ion to section 2-1:

Approved.* Acceptable to die author i ty having jurisdict ion. A-2-1. Approved. The National Fire Protection Association does

not approve, inspect, or certify any installations, procedures . equ ipment , or materials; nor does it approve or evahmte testing laboratories. In de t e rmin ing the acceptability of installations, procedures , equ ipmen t , or materials, the author i ty having jur isdic t ion may base acceptance on compl iance with NFPA or o ther appropr ia te s tandards. In the absence of such standards, said author i ty may require evidence of p roper installation, procedure , or use. The author i ty having jur isdic t ion may also refer to the listings or labeling practices of an organizat ion that is conce rned with p roduc t evaluations and is thus in a posit ion to de t e rmine compl iance with appropr ia te s tandards for the cur rent p roduc t ion of listed items.

Author i ty Having Jurisdict ion.* The organization, office, or individual responsible for approving equ ipment , an installation, or a procedure .

Exhibit 1 Comparison of Total Heat Released~'), As Measured by NFPA 264 and NFPA 259

PhSTM E1354 (NFPA 264 Effective Heat of Combus t ion ISO 1716 (NFPA 259)

Flux 25 k W / m z 35 k W / m ~ 50 k W / m ~ 75 k W / m ~ Potential Heat Sample Descr ipt ion ~b! H e (kJ/g) H e (kJ/g) H~ (kJ/g) H c (kJ/g) H (kJ/g)

Sample A NI N1 3.4 3.6 6.0 Sample B 10.4 12.2 13.8 12.6 25.0 Sample C / D NI NI NI NI 16.1 Sample E N1 6.0 5.2 5.9 15.0 Sample F 9.9 11.I 10.1 9.7 23.1 Sample G NI 4.0 5.8 8.4 17.6

~ 'Average Values of 6 tests us ing cone calorimeter; and 5 tests us ing ISO-1716. Cb~Samples were commerc ia l Unsh ie lded Twisted Pair (UTP), 4 pair j acke ted c o m m u n i c a t i o n cables con ta in ing no mineral fillers. NI: Sample did no t ignite u n d e r test protocol°

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. A-?-I. Authority Having Jurisdiction. The phrase "anthority having jurisdiction" is used in NFPA'documents in a broad. manner, sinc..e jurisdictious and approval agencies vary, as do their responslbihties. Where public safety is primary, the authority havingjurisdiction may be a federal, state, local, or other regional department or individiial such as a fire chief; fire marshal; chief of a tire prevention bureau, labor department, or health department;

l building official; electrical inspector;, or others having statutory anthority. For insurance purposes, an insurance inspection uepartment, rating bureau, or other insurance company representative may be the authority having jurisdiction. In many circumstances, theproperty owner or his or her designated agent assumes the role of the authority having jurisdiction; at go ve.m.ment,inst,?llatious, the commanding officer or departmental orqclal may ne me aumority having jurisdiction. Listed.* Equipment, materials, or services included in a list

published by an organization that is acceptable to the anthority having jurisdiction and concerned with evaluation of products or services, that maintains periodic inspection of production of listed equipment or materials or periodic evaluation of services, and whose listing states that either the equipment, material, or service meets identified standards or has been tested and found suitable for a specified purpose. A-2-1. Listed. The means for identifying listed equipment may

vary for each organization concerned with product evaluation; some organizations do not recognize equipment as listed unless it is also labeled. The authority having jurisdiction should utilize the system employed bythe listing organization to identify a listed product. Shall. Indicates a mandatory requirement. Should. Indicates a recommendation or that which is advised but

not required, SUBSTANTIATION., The terms being added are standard, NFPA definitions. They assist those who may not be familiar with the intended use of these words in an NFPA document. Adding them to NFPA 220 will clarify what riley mean in tile context of this document. COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: VOTE ON COMMITrEE ACTION: AFFIRMATIVE: 18 NOT RETURNED: 2 Matey, Nicholas

(Log #10) 220- 9 - (2-1 Limited - Combustible (LC) (New)): Accept in Principle SUBMrITER: RichardJ. Davis, Factory Mutual Research Corp. RECOMMENDATION: Add the following to the definition of "Limited - Combustible" (LC):

"Materials which have a notential heat value exceedin~ 3500 BTU/Ib (8141 Ku/k~ shall nass a large scale test " SUBSTANTIATION] A separate apl~endix item proposal elaborates on this. The current definition of LC does not allow for the use of materials which have been proven to be non p ropaga t ingbased on a large scale t e s t . COMMITTEE ACTION: Accept in Principle:

Revise Section 2-1, to read as follow:. Limited-Combustible. A building construction material not

complying with the definition of noncombust ible material that, in the xorm m which it is used, has a potential heat value not exceeding 3500 Btu/Ib (8141 kJ/kg), where tested in accordance with NFPA 259, Standard Test Method for Potential Heat of Building Materials. ~ Non load bearing wa l l and ceilin~, assembly materials which have nassed the large scale test nrocedure of any of the following:

FMRC 4411: 9r FMRC 4480: 9r UBC Standard 20-3: or UBC Standard 26-5: or

shall also be cons ide red as beine limited combustible. In a~] cases, materials m~l~l~ ~-~m~l~e~f, on~lp_l£.with (a) or (b) below. Materials subject to increase in combustibility or flame spread index beyond the limits herein established through the effects of age, moisture, or o ther a tmospheric condit ion shall be considered combust ible .

(a) Materials having a structural base of noncombust ib le material; with a surfacing not exceeding a thickness of 1 /8 in. (3.2 ram) that has a flame spread index not greater than 50.

.(b) Materials, in the form and thickness used, other than ,as described in (a), having ne i ther a flame spread index greater than 25 nor evidence of cont inued progressive combustion and of such composit ion that surfaces that would be exposed by cutting througil tile material on any plane would have nei ther a flame spread index greater than 25 nor evidence of cont inued progressive combust ion .

Add the newly in t roduced refer lmced documents to Chapter 4. COMMITI'EE STATEMENT: The revised language for this section offers a second option for de termining if a given mater ia l could be classified as l imited combustible by means of a second test option-namely a large scale test. In addition, this also reiterates the need to maintain supplemental information for enhancing the test method by verifying compliance with the item (a) and (b) criteria of the original text. N U M B E R OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 12 NEGATIVE: 5 ABSTENTION: 1 NOT RETURNED: 2 Matey, Nicholas

EXPLANATION OF NEGATIVE: BERHINIG: We have voted negative on this proposal because: 1 . .UBC Standard 26-5 is no t an appropriate standard to measure

combustibility. UBC Standard 26-5 is a test me thod to measure the density of smoke f rom the burn ing or decomposi t ion of plastic maten"als. Also, UBC Standard 26-5 does not ' inc lude any condit ions of acceptance.

2. The scope of [SO 97-5 is unknown to us. We have searched several places and have been unable to locate [SO 97,5.

Note: Support ing material is available for review at NFPA Headquarters .

DAVIS: There are two typos - UBC Standard 26-5 should be changed to 26-4. ISO 97-5 should be changed to [SO 9705.

The following text should be added to the proposed text: ~Where limited combustible material which has n~L~ed a large

scale test as def ined above is used on walls, its height shal[ Ipe limited to the lesser o f its listed height or 75 ft above the lowest level of fire dena r tmen t access."

Substantiation: See the proposed changes for Log #11. GEWAIN: The test me t hods re fe renced are not developed in

accordance with consensus procedures. Until that is done. they are no t appropria te for inclusion in NFPA 220.

MESSERSMITH: It appears that the Committee 's revisions to the original proposal have gone beyond the intent o f the original sub .mittal .wi).ich sought to add the requi rement for a large scale test m adctmon to the potential hea t test already required. I do not unders tand the connect ion between limiting potential heat and limiting flame propagation. The concept oi~ hmiting the potential heat o f a material (i.e., a l imited combustible material) is to limit the total amount of heat that will be l iberated if the material is consumed by fire. The proposal will waive the potential heat test for nonioad bearing wall and ceiling assemblies in favor of measuring the potential for fire to propagate over the surface as de te rmined i n a large-scale test. I should point otit that I am not familiar with most of the new test procedures being proposed for inclusion; however, the substantiation submit ted with Log #10 implies that these are large scale tests to measure the potential of flame propagation. Is that true in every case?

I would be in favor of retaining the existing definition of limited combustible material or accepting Log #10 as originally submitted.

WILLS: This proposal provides the wrong approach to address the proponents concern. The definition of limited combustible is in tended to establish a limit for the potent ial heat of component building construction materials i n d e p e n d e n t of their appJic~ation or use within the building. The existing definition only measures one attribute and the definition is not in tended to be application specific. Code sections that address specific conditions in the building should use the limited combnstible definition if it is deemed necessary along with o ther tests ~aad limitations that should apply. These specific code sections should also include exceptions where tile exceptions are justified for tile specific ap~, hcation.

This proposal introduces large scale tests that measure performance and propert ies o ther than potential heat . Tliese proposed tests are designed to address specific applications Of building construction. Where these tests are necessary, they should be included in the code as requirements or exception for their specific application. They should not be included in the definit ion of l imited combustible.

The wording of tile proposal would allow any of the five tests to be applied for either nonloadbear ing wall assemblies or for ceiling assemblies. I doub t that the scope statements for each of these

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tests would provide for both these applications, however, this is difficult to ascertain since none of the tests were provided to die committee for review.

In summary, the limited combustible definition is the wrong place to include testing requirements that are more appropriately addressed as exceptions to the exterior wall requirements. EXPLANATION OF ABSTENTION:

HOUSER: I did not have the benefit of d!e discussion pertaining to Mr. [)avis' proposal to utilize large-scale tests as an alternate metbod to classify nonload-bearing walls and ceilings as "limited- combustibles"

(Log #8) 220- 10- (2-1 Limited-Combustible): Reject SUBMITTER: Rick Thornberry, W.R. Grace RECOMMENDATION: Revise text as follows:

Limited-Combustible ~ . A bnilding construction material not complying with the definition of noncombustible material that. in the form in wlfich it is used, is a material that conforms to eitber one of tile following, conditions:

L has a potential heat value not exceeding 3,500 Btu per lb (8141 kJ/Kg), when tested in accordance with NFPA 259, Standard Test Method for Potential Heat of Building Materials, and complies with one of the following paragraphs (a) or (b)..M.atefia!2 z'.z'bjeet

limi+~ kcrcin czmb!i;ked t!:r.~'.:'g!= "d=c cffcctz c.f agz, mc2:t'.=rc, ".:r other a+~:~zp!:cr!c cond!t!~:: zka!l :=31 ~c dcfi=cd a: !!mired .co ;:I t~:='3*! ~ ! co

(a) Materials having a structural base of noncombustible material, with a surfacing not exceeding a thickness of 1/8 in. (3,2 into) that bas a flame spread rating not greater than 50.

(b) Materials, in the form and thickness used, other than as described in (a), having neither a flame spread rating greater fllan 25 nor evidence of continued progressive combustion and of" such composition tbat surfaces that would be exposed by cutting through the material on any plane would have neither a flame spread rating greater than 25 nor evidence of continued progressive combustion.

~. has a maximum 60 second average rate of heat release not

exceeding 75 kW/m 2 and an averaee total heat release not

exceedin~ 25 m l / m 2 wllen tested in accordance with NFPA 264, Standard Metllod of Test for Heat and Visible Smoke Release Rates for Materials and products Using an Oxygen Consumotion Calorimeter, using the retainer frame and the spark igniter at a

beatin~ flux of not less than 75 kW/m 2 for a duration of 15 minutes ,after the delay time of the annaratus. Sustained flaming shall not occur and Ore mass loss shali not exceed 50 percent.

Materials subject to increase in combustibility or flame st)read ratin~ bey0qd tbe limits llerein established througdl the effects of age, moisture, or other atmospheric condition shall not be defined as limited combustible.

Also, add NFPA 264-1995 to Section 4-1.1 NFPA Publications. SUBSTANTIATION: Tbe suggested maximum values tot the average maximum t50 second rate of heat release and tile average total heat release are based on a report by the BCMC Task group on Noncombustibility and Degrees of Combustibility Subcommittee on Data Analysis for a Class 1 degree of Combustibility wbere Class 0 is considered to be the equivalent of a noncombust ible material. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See the Committee Statement on 220-1 (Log #1). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 18 NOT RETLIRNED: 2 Matey, Nicholas

(Log #7) 220- 11 - (2-1 Noncombustible Material): Reject SUBMITTER: Rick Thornberry, W.IL Grace RECOMMENDATION: Revise text as follows:

Noncombustible Material. A buildin~ construction material that, in the form in which it is used and under the conditions anticipated, will not ignite, burn, suppor t combustion, or release flammable vapors, when subjected to fire or heat. Materials that

conform to either one of the followin~ test conditions shall be c o . s i t , r e d noncombust ib le materials:

1. Materials tha.t-a~ reported as passing ASTM E136, Standard Test Method for Behavior of Materials in a Vertical Tube Furnace at 750°C, _t.^u i. . . . . . :.~_^.~ . . . . . . t....~:t.t . . . . . .a-^l. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . o r

~. Materials havin~ a maximum 60 second average rate of heat

release not exceeding 25 kW/m 2 and an average total heat release

not e~ceeding 10 m l / m 2 when tested in acqordance with NFPA ~64, Standard method of Test for Heat and Visible Smoke Release Rates for Materi~ls alld Products Using an Oxygen Consumption Calori~qeter, usin~ the retainer frame and snark i~niter at a beatin~

flux of not less than 75 kW/m 2 for a duration of 15 minutes after the delay time of the apparatus. Sustained flaming shall not occur and the mass loss shall not exceed 50 nercent.

Materials subject to increase in combustibilitv beyond tile limits laerein established throutzb the effects of nee. moisture, or other atmosplleric condition shall riot be considered noncombustible

Also, add NFPA 254-1995 to Section 4-1.1 NFPA Publi,~ttiotLs SUBSTANTIATION: The suggested maximunl values tor the average maximum 60 second rate of heat release and tile average total heat release are based on a report by tile BCMC Task Group on Noncombustibility and Degrees of Combustibility Subcommittee on Data Analysis for a Class 0 degree of combustibility where Class 0 is considered to be tile equivalent of a noncombust ible material. COMMITTEE ACTION: Reject. COMMITTEE STATEMENT: See tile Committee Statement on 220-1 (Log #1). NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATWE: 18 -NOT RETURNED: 2 Matey, Nicbolas

(Log #9) 220- 12 - (2-1 Noncombustible Material): Acce~t in Principle SUBMITTER; Marcelo M. Hirscbler, GBH In t l RECOMMENDATION- Do not alter the test method that is used in the standard now for assessing tile requirements for noncombustible materials, wbicb is based on ASTM E136. SUBSTANTIATION: The oxygen bomb calorimeter has insufficient accuracy and precision at low values of heat of combustion to be an adequate metho-d for assessing noncombustlbility. NFPA 259 (which is a version of tile oxygen bomb calorimeter) shows tbe precision of the test method to be as follows: 465 kJ/kg (200 BTU/Ib) in repeatability and 1160 kJ/kg (500 BTU/Ib) in interlaboratory reproducibility.

Tile following discussion sllows the problems with accul aty ,d tile test method. The oxygen bomb calorimeter is ,t method h,I determining the theoretical (or complete or absolute) ~ah,iti, energy (or heat of combustion), as opposed to the eflective (of practical) values. The reason such instruments are used is tl~ e n s u r e that die c o r r e c t v a l u e is c h o s e u . As such they i ep l - eSe i l [ [ b e following chemical equations for combustible fuels conutiniug only carbon, hydrogen, and oxygen:

C + 0 2 = CO 2

4 H + 0 2 = 2 H 2 0

For hydrocarbon fuels: - C H 2 - + 0 2 = CO 2 + H 2 0

However, when building materials are more complex, because they contain other elements, there is a certain inconsistency in tile equation and in the energy calculated.

1. e l : Thus, for example, wben PVC is burnt in an oxygen bomb, depending on the fraction of bydrogen atoms present, there will be different proport ions of the following two equations:

(C2HBCI)n + 2 - 5 n O 2 = 2 n C O 2 + n H 2 0 + n HC1

(C2H3C1)n + 2 . 7 5 n O 2 = 2 n C O 2+1 .5 n H 2 0 + 0 . S n C I 2

where the two equa fons differ by $80 kJ/kg.

2. S: Combustion of materials containing sulfur also depends oil the final product. Typically the combustion bomb generates

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sulfuric acid as the final sulfur conta in ing product , while fu rnace combus t ion genera tes sulfur dioxide (with the sulfur less fully oxidized). There fore , the convent ion in b o m b calorimetry is to de t e rmine values of calorific value o f fuels ( inc luding coal), by referr ing to the quanti tat ive conversion to sulfur dioxide, and ignor ing the conversion to sulfuric acid (or sulfur trioxide) that occurs, by us ing a conversion factor based on the sulfur content . Interestingly, gypsum (which is calcium sulfate dehydra te) , is a bui ld ing material conta in ing sulfur. T he typical fuel conta in ing sulfur is coal. The difference between conversion to sulfur dioxide and sulfuric acid is 9410 kJ/kg.

3. N: Combus t ion of materials conta in ing n i t rogen also has a convention: the hea t of convent ion is normally calculated a s suming that all the n i t rogen is conver ted into molecular ni trogen. However, tha t is no t what h a p p e n s in oxygen b o m b calorimetry, where n i t rogen oxides and nitric acid are actually formed. Thus , a correct ion is applied to account for the following equat ion:

HNO 3 = 0.5 H 2 0 + 0.5 N 2 + 1.25 0 2, with a ne t hea t of reaction of 1017 kJ/kg.

4. F: Combus t ion o f materials con ta in ing f luorine is generally represen ted as e n d i n g in the format ion of carbon tetrafluoride (CF4) and of hydrogen f luoride (HF), in varying proport ions. The equa t ion is as follows:

C a H b O c F e + (a+b /4 -c /2 -e /4 ) 0 2 + ( n + l / 2 ) * e * ( 1 - x ) - b / 2 ) H 2 0 = (a-ex/4) CO 2 + e x / 4 CF 4 + e(1-x) (HF) + e(1-x) n H 2 0

where x is the fraction o f f luor ine .a toms converted to CF 4 as opposed to converted to HF. The energy of the conversion of CF 4 to HF is approximate ly 192 kJ/kg. Moreover, f iuorine materials will attack the walls o f the b o m b calorimeter .

5. Si: C o m p o u n d s conta in in~ silicon are impossible to convert complete ly to their final oxidat ion product , witich is silica ( S i t 2), by convent ional m e a n s because as bu rn i ng proceeds, the material becomes covered by a layer of silica which prevents access of oxygen and leads to the format ion of a residue. T he only way to obtain a reliable result of hea t of combus t ion o f materials con ta in ing silicon (such as silicones) is by a m e t h o d which combines the material with an organic f luorine c o m p o u n d (the value of which has been accurately assessed in advance) in rotat ing b o m b conta in ing also water and aqueous HF. This converts all the Si into fluorosilicic acid, and the results can t hen be calculated back.

6. P: C o m p o u n d s conta in ing phospho rus are exceedingly difficult to assess by oxygen b o m b combus t ion calorimetry. There are four major problems: (1) various phospho rus acids with different energies of di lut ion are fo rmed in various concent ra t ions t h r o u g h o u t the oxygen bomb; (2) the combus t ion products conta in di f ferent types of p h o s p h o r u s oxyacids, each one o f which has a different hea t of format ion; (3) the bu rn i ng c o m p o u n d gets covered by p h o s p h o r u s oxides and acids, which inhibi t fu r ther combust ion; and (4) the b o m b calor imeter walls are at tacked and metal phospha t e s are formed, so tha t the r e c o m m e n d e d wall materials shou ld be c o r u n d u m or gold, s ince pyrex glass, quartz, stainless steel t i tanium, porcelain, a n d p la t inum all suffered heavy weight losses. For example, d e p e n d i n g on whe the r a rotat ing bomb or a static b o m b is used, the fraction o f pyrophospbor ic acid fo rmed varied f rom 10 to 18% and tha t of t r iphosphor ic acid f rom 1 to 3%.

7. Auxiliary combus t ion material: W hen an auxiliary material is used for assessing the hea t of combust ion , a 1% error in the assessment of the hea t of combus t ion of the auxiliary material (such as benzoic acid), which is typically used in the order of 20% energy loading, cor responds to a 5% error in the total e n e r g y / b e a t measured . Thus , at a value of 1500 kJ /kg tha t would be an error of 75 kJ/kg, and this would be a systematic er ror for that series of exper iments .

8. Moisture content : T he mois ture con ten t of the bui ld ing material is critical, because the combus t ion reaction considered in the oxygen b o m b is that to convert to gaseous water. Thus , if a material contains water, the water will have react ion to vaporize the water content . Thus , results mus t be expressed as a func t ion of the original mois ture con ten t for t h e m to be valid. This matters, of course, for materials tha t absorb mois ture when exposed to the a tmosphere .

This clearly indicates that the accuracy o f the oxygen bomb calor imeter is poor at values of very low hea t of combust ion , which is no t what this test m e t h o d was in t ended for. Its in tent is to "

measure hea t con ten t of materials, such as fossil fuels, with ltigb beats of combus t ion .

In conclusion, any r e c o m m e n d e d cut-off value close to the precision limit of the test m e t h o d (i.e., 1160 kJ/kg) , such as a value of 1365 kJ/kg, is dangerous ly close to the values of the i nhe ren t errors of oxygen bomb calorimetry us ing couunon materials.

Refe ren ces: * Mansson, Margret, "Determinat ion of Calorific Values of

Building Materials - A Guide," SP Nordtest Report Project 871-90, Swedish National Tes t ing and Research Institute, Boras, Sweden, 1991.

* Head, Ar thur J, and Good, William D., "Combus t ion of Liquid /Sol id C o m p o u n d s with Nonmetal l ic Hetero Atoms," Chapter 9 in "Combust ion Calorimetry," "Volume 1, Exper imenta l Chemical thermodynamics , " Eds. Stig S u n n e r & Margre t M. Mansson) , Pe rgamon Press, Oxford, UK (for Int. Un ion Pure & Applied Chemistry, IUPAC), 1979.

*Mansson, Margret and Hubbard , Ward N., "Strategies in the Calculation of Standard-State Energies of Combus t ion f rom die Experimental ly De te rmined Quantit ies," Chapte r 5 in "Combust ion Calorimetry," "Volume 1, Exper imenta l Chemical thermodynamics , " Eds. Sfig S u n n e r & Margret M. Mansson) , Pe rgamon Press, Oxford, UK (for Int. Un ion Pure & Applied Chemistry, IUPAC), 1979.

*Hu, Andrew T., Sinke, G.C., Mansson, Margret and Ringner , Birgitta, "Test Substances for Bomb Combus t ion Calorimetry, p- Chlorobenzoic Acid." J. Chem. The rmodynamics , 4, 283-99 (1972).

*Mansson, Margret, "Thermochemis t ry - Some Recent Lines of Development ," Pure & Applied Chemistry, ~ 417-26 (1983).

*Mausson, Margret, "A 4.5 cm $ Bomb Combus t ion Calor imeter ,and an Ampou le Tecbn ique for 5 to 10 m g S a m p l e s widr Vapour Pressures Below Approximate ly 3 kPa (20Tor r ) , " J. Chem. The rmodynamics , 5_, 7232 (1973).

*NFPA 259, S tandard Tes t Method for Potential Heat of Building Materials. COMMITTEE ACTION: Accept in Principle. COMMITTEE STATEMENT: No specific action is needed for this proposal. The commi t tee did not make any changes to the defini t ion of non-combus t ib le no r were ,any changes accepted to revise how the non-combust ib le at t r ibute of a material would be de te rmined . The text as shown in the 1995 edition for dais

ticular i tem will remain as shown. BER O F C O M M I T T E E MEMBERS ELIGIBLE T O V O T E : 20

VOTE ON COMMITTEE A C T I O N : AFFIRMATIVE: 17 ABSTENTION: 1 NOT RETURNED: 2 Matey, Nicholas

EXPLANATION OF ABSTENTION: HOUSER: I did no t have the benefi t of the Commit tee ' s

discussion per ta in ing to Dr. Hirschler 's proposal to retain only the vertical tube furnace (ASTM E 136) as the test me thod to de t e rmine "noncombust ib le" materials. A l though 1 am speaking nei ther for nor against the proposal, it is worth not ing tha t the oxygen b o m b is simply a test me thod . The b o m b appara tus is used, in conjunct ion with the muff le furnace , to reasonably extract a substantial por t ion o f the potential hea t tha t the spec imen contains. Like any o ther me thod , NFPA 259 has l imitations and Dr. Hirschler has poin ted some of those l imitations out. However, I do no t believe that the oxygen b o m b was in t ended to be a cross-check of the theoretical t he rmochemica l results that complex materials emi t as they u n d e r g o fractional or comple te decomposi t ion . It should also be no ted thar gypsum does not typically contain e lementa l sulfur. The a tom of sulfur is chemically b o u n d in e sulfate radical.

(Log #CP5) 220- 13 - (3-4.1 Exception (New)): Accept S U B M I T T E R : Technica l Commi t t ee on Building Construct ion RECOMMENDATION: Add a new Exception to Section 3-4.1 as follows:

"Exterior walls grea ter than 30 ft (9.1m) f rom the property line shall be permi t ted to be of heavy t imber const ruct ion provided the 2-hour rat ing as requi red by Table 3-1 is ma in ta ined and sucb walls conta in no combust ib le concealed spaces."

Make this Exception No. 1 and r e n u m b e r the other Exceptions as needed . Revised text will read:

3-4.1 Type IV construct ion shall be that type in which exterior and inter ior walls and structural m e m b e r s that are port ions of such walls are of approved noncombus t ib l e or limited-

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combust ib le materials. O t he r inter ior s tructural members , inc luding columns, beams, girders, trusses, arches, floors, arid roofs, shall be of solid or l amina ted wood wi thout concea led spaces and shall comply with the provisions of 3-4.2 t h rough 3-4.6. In addit ion, s tructural m e m b e r s shall have fire resistance ratings not less than those specified in Table 3-1.

Excention No. 1: I~gterior walls grea ter titan 30 ft (9.1m) fr0nl the orooertv line shall be oermi t ted to be of h e a w t imber construct ion orovided t h e 2 - h o u r rat ine as reuui red by Table 3-1 is ma in ta ined and sucb walls con ta in no combust ib le concealed

Exception No. 2: Interior columns, arches, beams, girders, and trnsses of approved materials odaer t han wood shall be permit ted, provided they are protected to provide a fire resistance rating of not less than 1 hr.

Exception No. 3: Certain concealed spaces shall be permi t ted by the exception to 3-4.4. S U B S T A N T I A T I O N : T he use of heavy t imber construct ion for exter ior wall assemblies would current ly be restricted by NFPA 220, Table 3-1 for all c ircumstances. If an adequate set-back (30 ft or greater) is main ta ined , exterior walls of heavy t imber const ruct ion shou ld be acceptable provided they have demons t r a t ed the 2-hr fire e n d u r a n c e criteria and provided there are no concealed spaces of combust ib le cons t rucnon . COMMITTEE ACTION: Accept. NUMBER OF COMMITTEE MEMBERS ELIGIBLE TO VOTE: 20 VOTE ON C O M M I T r E E ACTION:

AFFIRMATIVE: 15 NEGATIVE: 3 NOT RETURNED: 2 Matey, Nicholas

EXPLANATION OF NEGATIVE: HOUSER: 1 did not have d ie full benefi t of die Commit tee ' s

discussion on dais proposal to permi t combust ib le exter ior walls in Type IV (heavy t imber ) const ruct ion and do no t feel tha t the snbstant ia t ion is persuasive e n o u g b to enter ta in t h e p r o p o s e d change at this point in t ime. Some of the previous Commi t tee del iberat ions have drawn a t tent ion to an restrictive inclusion of "log cabin" styles of cons t ruc t ion as Type V (wood f ramed) . However, I believe dlat a s t raight forward except ion for full d imens ion natural t imbers in NFPA 220 or a r e c o m m e n d a t i o n to tbe Commi t t ee on Safety to Life to permi t an increase in allowable bui ld ing areas based on the probable or actual i nhe ren t fire resistance of these s t ructures would be more in order than a blanket except ion for all "heavy t imber" exterior walls. Fur tber ques t ions inc lude the following:

(a) Should there be a he igh t limitation for heavy t imber exterior walls.

(b) Is a thirty-foot setback adequate to reasonably retard radiant hea t t ransfer to and f rom the walls.

(c) What is the potential affect of the collapse of the exterior wall as a f imct ion of bui ld ing he igb t - we have little or no historical in format ion on tiffs p h e n o m e n a for these walls.

(d) Wbat is the ,affect on fire pe r fo rmance if light combust ib le claddings are a t tached to the walls.

(e) How will these provisions apply to built-up, eng ineered , adhered , or laminated wood members?

(f) Unlike lightweight, d imens iona l wood f raming, is d ie fire resistance of heavy t imber const ruct ion d e p e n d e n t on species, grade, and "growth" (old growth versus juveni le) .

(g) Are fire pe r fo rmance characteristics of heavy t imber m e m b e r s affected by tempera ture , humidi ty , or long-term weather exposure .

MESSERSMITH: Type IV, or heavy t imber construct ion is a special category of Type III construct ion. In both types of const ruct ion exter ior walls mus t be built of "approved noncombus t i b l e or l imited combust ib le materials." Tbis change will create an inconsis tency in the s tandard between these two types of construct ion. More impor tant ly f rom a fire protect ion point of view, cons t ruc t ing the exterior walls of heavy t imber will add fire loading to the bui ld ing since a combnst ib le material will now be allowed where previously it was not.

WILLS: Heavy t imber const ruct ion is recognized by all the U.S. Model Codes with appropr ia te he igh t and area limitations. The permit ted applicat ions o f this type of construct ion has been just i f ied by a long track record of pe r fo rmance . However, all die mode l codes require noncombus t ib l e exterior wall cons t ruc t ion i n d e p e n d e n t of the dis tance f rom die properly line. The pe r fo rmance track record is based on noncombus t ib l e exterior wall construct ion. Heavy t imber const ruct ion with combust ib le exterior walls is permit ted by the codes only as a different type of construct ion with more restrictive applications. Similarly, heavy t imber const ruct ion with combust ib le exterior walls is present ly allowed by NFPA 220 as Type V (111). Code users unde r s t and the

basic construct ion types and recognize the relat ionship between the construct ion type and the uses permi t ted for that construction. Major changes to a const ruct ion type m u s t be just l f ied by documen ta t i on tha t addresses the impact on the permi t ted uses and limitations. No documen ta t i on was provided to the commit tee to justify this relaxation in e basic type of construct ion requ i rements . C O M M E N T ON AFFIRMATIVE:

FRANCIS: ! would like to change my ballot based on negatives received on the most recent NFPA 220 commit tee actions. Specifically change my ballot to Affirmative on Log #CP5.

Reason: The policy of NFPA is to move to pe r fo rmance based requ i rements wherever possible. The negatives received on tltis issue cite traditional satisfactory pe r fo rmance and increased fire load, a m o n g o ther things, ,as the reason for main ta in ing the cnr ren t language regarding Heavy T imber Construct ion. The

~ roposal s imply recognizes tile well known characteristics of Heaw imer and puts it into a more pe r fo rmance or iented category.

This is in keeping with the above m e n t i o n e d polio/'.

(Log #11 ) 220- 14 - (A-2-1 Limited - Combust ib le (LC) (New)): Accept in Principle SUBMITTER: Ricbard J. Davis, Factory Mutual Research Corp. R E C O M M E N D A T I O N : Add the following Append ix item:

A-2.1 Limited Combustible. Materials wltich do no t meet the criteria for l imited combust ib le (LC) in Section 2.1 can be considered to be LG if it passes a large scale test such as the Factory Mutual Research Cornora t ion (FMRC) Standard 4411. FMl~G$tandard 4880 or the Un i fo rm Building Code (UBC) $~nOrd 26-4 (formerly 17-6). The Flame Spree0 Index (FSI) should no t be used bv itself to classify bui ldin~ materials that are plastic. Large scale tests, such as the FMRC C o m e r Tes t (Standard 4880) have shown tha t some olastic materials with a FSI not exceedine 25 can exoer ience a seff-orooazatin~ fire. S U B S T A N T I A T I O N : This proposal e-lal3orates on acceptable large scale tests tha t can be used to categorize LC materials whicl~ do no t mee t the existing defini t ions in Section 2.1. COMMITTEE ACTION: Accept in Principle.

Add append ix text for A-2-1 to read as follows: A-2-1 Limited - Combust ible . Some materials which have a

notential hea t value that exceeds 3500 Btu / Ib (8141 kl /k~) as de t e rmined by NFPA 259. S tandard Tes t Method for Potential Heat of Building Materials.have successfully passed large scale tests such as the FMRG Corne r Test. I'FMRC 4411 .... and FMRC 4880...). The 171Bll0e Spread Index (FSI) shou ld not be used by itself to Cl~sifs' bu i ld ing materials. Laree scale tests, sucl~ ,as the FMRC, Corner Test (Standard 4880) have shown that some materials with a FSI not; exceeding 25 can exner ience a self-propa~',tting fire. COMMITTEE STATEMENT: Tile commit tee has incorpora ted informat ion to make the user aware of the fact dlat odler testing opt ions should be made available to de te rmine if a material can also be d e t e r m i n e d to be l imited - combust ible . This Commi t tee Action and append ix text will correlate with die Commi t tee Action on 220-9 (Log #10). NUMBER O F COMMITTEE MEMBERS ELIGIBLE T O VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 13 NEGATIVE: 5 NOT RETURNED: 2 Matey, Nicholas

EXPLANATION OF NEGATIVE: BERHINIG: We have voted negative on this proposal to modify

die append ix material for Section 2-1 since we have voted negative on the proposal to Section 2-1.

A sugges ted wording for A-2-1 is: Limited Combust ible . Some materials which have a potential

hea t value tha t exceeds 3,500 b tu / Ib (8,141 kJ/kg) as de t e rmined by NFPA 259, S tandard Tes t Method for Potential Heat of Building Materials, have successfully passed large scale tests.

DAVIS: Add the following text to the end of A-2-1: "The te rm "limited combust ible" h ~ been def ined b ~ e d on

pe r fo rmance tests, however, conceptual ly it is mean t to describe materials tha t will no t exner ience a serf-propagating fire. I tems that are used on walls and are c 'onsidered l imited combust ible based on one of the large scale tests no ted in S ~ t i o n 2-1 may hav~ be ieh t limitations imoosed by the testin~ a~encv ~[enending ofl the snecific test details. While these materials should result in a self- p ropagat ing fire of themselves wben used according to listin~

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reou i rements they may allow fire nrooa~at ion for a sufficient dis tance ( that is ~reater than that of products whicl~ mee t the criteria of the o ther def ini t ions of l imited combust ible) tha t it may allow wickin~ vertically to windows above, making_ their use orl exterior walls ex tendin~ above the fire depa r tmen t ' s rt~ach undes i rab le . "

Substantiat ion: T he p roposed change allows for the use of l imited-combust ible materials based on large scale testing, bowever, it limits tbe usage he igh t of those materials used on walls to help prevent vertical fire spread in high-rise buildings. Due to the impor tance of a high-rise bui ld ing and its complexi ty with regard to fire safety, minimal fire spread on exterior walls may not be tolerable as cons t ruc t ion details shou ld allow for con t ingen t protect ion should sprinklers be ou t of service.

GEWAIN: See my Explanat ion of Negative on Proposal 220-9 (Log #10).

MESSERSMITH: See my Explanat ion of Negative on Proposal 220-9 (Log #10).

WILLS: See my Explanat ion of Negadve on Proposal 220-9 (Log #10).

(Log #6) 220- 16 - (Appendix D (New)): Reject Note: Tiffs Proposal appea red as C o m m e n t 220-18 which was

he ld f rom the Annua l 95 ROC on Proposal 220-28. SUBMITTER: Rick Thomber ry , W.I~ Grace R E C O M M E N D A T I O N : Add a new Append ix D as indicated in the original proposal . S U B S T A N T I A T I O N : This is a c o m p a n i o n c o m m e n t to our c o m m e n t s on proposals no. 220-10 and 220-13. If e i ther of those c o m m e n t s are accepted in some form by the Commit tee , it would be appropr ia te to accept this c o m m e n t in order to provide a source of reference materials for the users of this s tandard. COMMITTEE ACTION: Reject. C O M M I T r E E STATEMENT: See the Commi t tee Action on 220-4 (Log #2). NUMBER OF COMMITTEE MEMBERS ELIGIBLE T O VOTE: 20 VOTE ON COMMITTEE ACTION:

AFFIRMATIVE: 18 NOT RETURNED: 2 Matey, Nicholas

(Log #CP4) 220- 15 - (Table C-l): Accept SUBMrrTER: Teclmical Commi t t ee on Building Const ruc t ion R E C O M M E N D A T I O N : Identify the Table in Append ix C as Table C-1. Delete the entry 'Roof insulat ion board ' in I tem 3.c. Tha t por t ion of the Table tha t is affected is shown below.

3. Insulat ion a. Glass fiber, semirigid,

no vapor barrier 1 3.0 3040 b. Rock wool batt ing,

paper enc losure 3 2.4 1050

c.d:. Cork (reconst i tuted cork sheet) 1/4 14.8 I lA10

d.e~Cellulose minera l board 2 47.8 2250

S U B S T A N T I A T I O N : The commit tee is of the opinion that ' roof insulat ion board ' is too broad. Given the wide range of this material and the composi te materials available, the commi t tee does no t believe tha t a one size fits all descr ipt ion and value is of benefi t for dais Table. C O M M I T T E E ACTION: Accept. NUMBER OF. COMMITTEE MEMBERS ELIGIBLE T O VOTE: 20 VOTE ON COMMIT T E E ACTION:

AFFIRMATIVE: 17 ABSTENTION: 1 NOT RETURNED: 2 Matey, Nicholas

EXPLANATION OF' ABSTENTION: HOUSEI~ I agree that the descr ipt ion is too broad; however, I

,assume tha t s o m e o n e reviewed the old NBS data to see if "roof insulat ion board" was better def ined in the original repor t before suggest ing that the entry in Table C-1 be deleted.

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