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<br /> ASTM E119 Testing Method FIGURE 1:
<br /> According to Section 4.2 of ASTM E119-18,the fire test Code Path for Exposed Wood Fire-Resistance Calculations
<br /> Ledure is intended to do the following: "- ra
<br /> e test exposes a test specimen to a standard fire se
<br /> 73 'T4( t c 6,
<br /> controlled to achieve specified temperatures throughout " rKYstarlea k^
<br /> apreSWi Ie — 72" ,r alit' t
<br /> a specified time period. When required, the fire exposure �.,rt 3 �, ff
<br /> is followed by the application of a specified standard fire Fife dg;w,taeece des ` �Sources
<br /> hose stream applied in accordance with Practice E2226. f ^ -
<br /> The test provides a relative measure of the fire-test- • Engineenray one eompe(json ya��
<br /> response of comparable building elements under these fire •Alta '?tl 'o meThedsak . 104y,
<br /> ie , fr
<br /> exposure fire condti The seexposure
<br /> io not representative lad'
<br /> of al!fire conditions because conditions vary with changes
<br /> in the amount nature and distribution of fire loading,
<br /> ventilation, compartment size and configuration,and heat ii, s J j. Ill
<br /> sink characteristics of the compartment. Variation from the 722' ,11, i „k,
<br /> test conditions or test specimen construction, such as size, Calculated Aa na a t ,,
<br /> roc
<br /> materials, method of assembly,also affects the fire-test- "Itrehatutidith foe rstanca: wood' TF
<br /> response. For these reasons, evaluation of the variation i `arrA Woolf• �t1e ` ad
<br /> Is required for applcaoon to construction in the field. In aeeadence IS ofANSV(AgVC
<br /> Na i „e,., - don a ti lsoi,
<br /> Successful fire tests have been completed on numerous Coo o NMI s.
<br /> mass timber elements and assemblies,achieving fire-
<br /> resistance ratings of 3 hours or more.Additional tests
<br /> by manufacturers and others are ongoing. Most tests ,a. ''
<br /> are conducted according to ASTM E119 or its Canadian .
<br /> equivalent, ULC S101. Both utilize the same time- MS Chapter f8 ,!1 5 7
<br /> temperature curve and performance criteria and,as such, Fro of 1" "
<br /> C 5101 fire tests are usually acceptable to U.S. building ^i nl - `
<br /> • um to 6 krara mg fire reflstancel§yta 26e5Yts 'rr
<br /> ials. However,each projects building official should eptli s s a r'
<br /> consulted if choosing this design route. "'Sear ire-re variesp�ed elk rue ' V
<br /> Qe,fire-resistance t Wee and
<br /> To help building designers compare options,WoodWorks has 12mnatiorttleckneer. ns and tables are
<br /> Ia f compiled a web-based inventory of completed mass timber ploeafed: hil i $,
<br /> O fire tests.The Inventory of Fire Resistance-Tested ><TRItka ested Mass NDS r op � 01 I t il$ e•
<br /> �
<br /> Timber Assemblies& Penetrations is updated as new tests fi''4,110Prereeneng permitted fe Is. .ns.,
<br /> become available,and can be found at http://billy/2FRwAPG.
<br /> Calculation-Based Method
<br /> As referenced in IBC Section 722.1, NDS Chapter 16 can
<br /> be used to calculate the structural fire-resistance rating of
<br /> various wood products, including solid sawn,glulam, SCL, Average member strength properties are approximated
<br /> and CLT. from existing accepted procedures used to calculate design
<br /> properties. Finally, wood members are designed using
<br /> As noted by Douglas and Smart in Structure magazine,' engineering accepted en
<br /> "The design procedure allows calculation of the capacity p g 9 procedures found in NDS for allowable
<br /> stress design."
<br /> of exposed wood members using basic wood engineering
<br /> mechanics.Actual mechanical and physical properties The American Wood Council's(AWC's) Technical Report
<br /> of the wood are used,and member capacity is directly 10-Calculating the Fire Resistance of Wood Members and
<br /> calculated for a given period of time—up to 2 hours. Assemblies(TR 10) provides an in-depth explanation of the
<br /> Section properties are computed using an effective char concepts and background associated with exposed wood
<br /> depth,see,at a given time,t. Reductions of strength and fire design.This document also includes a number of design
<br /> stiffness of wood directly adjacent to the char kayer are examples for exposed structural wood members utilizing the
<br /> addressed by accelerating the char rate by 20 percent provisions of NDS Chapter 16.
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