ASTM D6305-08

Standard Practice for Calculating Bending Strength Design Adjustment Factors for Fire-Retardant-Treated Plywood Roof Sheathing

SIGNIFICANCE AND USE
This practice develops treatment factors that shall be used by fire retardant chemical manufacturers to adjust bending strength design values for untreated plywood to account for the fire-retardant treatment effects. This practice uses data from reference thermal-load cycles designed to simulate temperatures in sloped roofs of common design to evaluate products for 50 iterations.
This practice applies to material installed using construction practices recommended by the fire retardant chemical manufacturers that include avoiding exposure to precipitation, direct wetting, or regular condensation. This practice is not meant to apply to buildings with significantly different designs than those described in 1.3.
Test Method D 5516 caused thermally induced strength losses in laboratory simulations within a reasonably short period. The environmental conditions used in the laboratory-activated chemical reactions that are considered to be similar to those occurring in the field. This assumption is the fundamental basis of this practice.
SCOPE
1.1 This practice covers procedures for calculating bending strength design adjustment factors for fire-retardant-treated plywood roof sheathing. The methods utilize the results of strength testing after exposure at elevated temperatures and computer-generated thermal load profiles reflective of exposures encountered in normal service conditions in a wide variety of continental United States climates.
1.2 Necessarily, common laboratory practices were used to develop the methods herein. It is assumed that the procedures will be used for fire-retardant-treated plywood installed using appropriate construction practices recommended by the fire retardant chemical manufacturers, which include avoiding exposure to precipitation, direct wetting, or regular condensation.  
1.3 The heat gains, solar loads, roof slopes, ventilation rates, and other parameters used in this practice were chosen to reflect common sloped roof designs. This practice is applicable to roofs of 3 in 12 or steeper slopes, to roofs designed with vent areas and vent locations conforming to national standards of practice, and to designs in which the bottom side of the sheathing is exposed to ventilation air. These conditions may not apply to significantly different designs and therefore this practice may not apply to such designs.
1.4 Information and a brief discussion supporting the provisions of this practice are in the Commentary in the appendix. A large, more detailed, separate Commentary is also available from ASTM.  
1.5 The methodology in this practice is not meant to account for all reported instances of fire-retardant plywood undergoing premature heat degradation.
1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Jul-2008
• ICS: 91.060.20 - Roofs
• Technical Committee: D07 - Wood
• Drafting Committee: D07.07 - Fire Performance of Wood

Relations

• Replaces: ASTM D6305-02e1 - Standard Practice for Calculating Bending Strength Design Adjustment Factors for Fire-Retardant-Treated Plywood Roof Sheathing
• Effective Date: 01-Aug-2008
• Referred By: ASTM D7857-16 - Standard Test Method for Evaluating the Flexural Properties and Internal Bond Strength of Fire-Retarded Mat-Formed Wood Structural Composite Panels Exposed to Elevated Temperatures
• Effective Date: 01-Aug-2008
• Referred By: ASTM D6841-21 - Standard Practice for Calculating Design Value Treatment Adjustment Factors for Fire-Retardant-Treated Lumber
• Effective Date: 01-Aug-2008
• Referred By: ASTM D5516-18 - Standard Test Method for Evaluating the Flexural Properties of Fire-Retardant Treated Softwood Plywood Exposed to Elevated Temperatures
• Effective Date: 01-Aug-2008

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D6305 − 08
StandardPractice for
Calculating Bending Strength Design Adjustment Factors
1
for Fire-Retardant-Treated Plywood Roof Sheathing
This standard is issued under the fixed designation D6305; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope conversions to SI units that are provided for information only
and are not considered standard.
1.1 This practice covers procedures for calculating bending
1.7 This standard does not purport to address all of the
strength design adjustment factors for fire-retardant-treated
safety concerns, if any, associated with its use. It is the
plywood roof sheathing. The methods utilize the results of
responsibility of the user of this standard to establish appro-
strength testing after exposure at elevated temperatures and
priate safety and health practices and determine the applica-
computer-generated thermal load profiles reflective of expo-
bility of regulatory limitations prior to use.
sures encountered in normal service conditions in a wide
variety of continental United States climates.
2. Referenced Documents
1.2 Necessarily, common laboratory practices were used to
3
2.1 ASTM Standards:
develop the methods herein. It is assumed that the procedures
D9Terminology Relating to Wood and Wood-Based Prod-
will be used for fire-retardant-treated plywood installed using
ucts
appropriate construction practices recommended by the fire
D5516TestMethodforEvaluatingtheFlexuralPropertiesof
retardant chemical manufacturers, which include avoiding
Fire-Retardant Treated Softwood Plywood Exposed to
exposure to precipitation, direct wetting, or regular condensa-
Elevated Temperatures
tion.
1.3 Theheatgains,solarloads,roofslopes,ventilationrates,
3. Terminology
and other parameters used in this practice were chosen to
3.1 Definitions:
reflectcommonslopedroofdesigns.Thispracticeisapplicable
3.1.1 Definitionsusedinthispracticeareinaccordancewith
toroofsof3in12orsteeperslopes,toroofsdesignedwithvent
Terminology D9.
areas and vent locations conforming to national standards of
3.2 Definitions of Terms Specific to This Standard:
practice, and to designs in which the bottom side of the
3.2.1 bin mean temperature—10°F (5.5°C) temperature
sheathing is exposed to ventilation air. These conditions may
ranges having mean temperatures of 105 (41), 115 (46), 125
not apply to significantly different designs and therefore this
(52),135(57),145(63),155(68),165(74),175(79),185(85),
practice may not apply to such designs.
195 (91), and >200°F (93°C).
1.4 Information and a brief discussion supporting the pro-
visionsofthispracticeareintheCommentaryintheappendix.
4. Summary of Practice
Alarge, more detailed, separate Commentary is also available
4.1 The test data determined by Test Method D5516 are
2
from ASTM.
usedtodevelopadjustmentfactorsforfire-retardanttreatments
1.5 Themethodologyinthispracticeisnotmeanttoaccount
to apply to untreated-plywood design values. The test data are
for all reported instances of fire-retardant plywood undergoing
used in conjunction with climate models and other factors and
premature heat degradation.
the practice thus extends laboratory strength data measured
after accelerated aging to design value recommendations.
1.6 Thevaluesstatedininch-poundunitsaretoberegarded
as standard. The values given in parentheses are mathematical
5. Significance and Use
5.1 This practice develops treatment factors that shall be
1 usedbyfireretardantchemicalmanufacturerstoadjustbending
This practice is under the jurisdiction ofASTM Committee D07 on Wood and
is the direct responsibility of Subcommittee D07.07 on Fire Performance of Wood.
Current edition approved Aug. 1, 2008. Published September 2008. Originally
ε1
3
approved in 1998. Last previous edition approved in 2002 as D6305–02 . DOI: For referenced ASTM standards, visit the ASTM website, www.astm.org, or
10.1520/D6305-08. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
2
Commentary on this practice is available from ASTM Headquarters. Request Standards volume information, refer to the standard’s Document Summary page on
File No. D07–1004. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D6305 − 08
strengthdesignvaluesforuntreatedplywoodtoaccountforthe where:
fire-retardant treatment effects. This practice uses data from
M = average maximum moment,
reference thermal-load cycles designed to simulate tempera-
D = number of days of elevated temperature exposure,
tu
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation:D6305–02 Designation: D 6305 – 08
Standard Practice for
Calculating Bending Strength Design Adjustment Factors
1
for Fire-Retardant-Treated Plywood Roof Sheathing
This standard is issued under the fixed designation D6305; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1
´ NOTE—The title for Table 6 was corrected from “One” to “Three Exposure Temperatures” in October 2002.
1. Scope
1.1 Thispracticecoversproceduresforcalculatingbendingstrengthdesignadjustmentfactorsforfire-retardant-treatedplywood
roof sheathing.The methods utilize the results of strength testing after exposure at elevated temperatures and computer-generated
thermalloadprofilesreflectiveofexposuresencounteredinnormalserviceconditionsinawidevarietyofcontinentalUnitedStates
climates.
1.2 Necessarily, common laboratory practices were used to develop the methods herein. It is assumed that the procedures will
be used for fire-retardant-treated plywood installed using appropriate construction practices recommended by the fire retardant
chemical manufacturers, which include avoiding exposure to precipitation, direct wetting, or regular condensation.
1.3 The heat gains, solar loads, roof slopes, ventilation rates, and other parameters used in this practice were chosen to reflect
common sloped roof designs. This practice is applicable to roofs of 3 in 12 or steeper slopes, to roofs designed with vent areas
andventlocationsconformingtonationalstandardsofpractice,andtodesignsinwhichthebottomsideofthesheathingisexposed
toventilationair.Theseconditionsmaynotapplytosignificantlydifferentdesignsandthereforethispracticemaynotapplytosuch
designs.
1.4 InformationandabriefdiscussionsupportingtheprovisionsofthispracticeareintheCommentaryintheappendix.Alarge,
2
more detailed, separate Commentary is also available from ASTM.
1.5 The methodology in this practice is not meant to account for all reported instances of fire-retardant plywood undergoing
premature heat degradation.
1.6This practice is written in inch-pound units with SI units provided in parentheses for information only.
1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
3
2.1 ASTM Standards:
D9 Terminology Relating to Wood Terminology Relating to Wood and Wood-Based Products
D5516 Test Method for Evaluating the Flexural Properties of Fire-Retardant Treated Softwood Plywood Exposed to Elevated
Temperatures
3. Terminology
3.1 Definitions:
3.1.1 Definitions used in this practice are in accordance with Terminology D9.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 bin mean temperature—10°F (5.5°C) temperature ranges having mean temperatures of 105 (41), 115 (46), 125 (52), 135
(57), 145 (63), 155 (68), 165 (74), 175 (79), 185 (85), 195 (91), and 175°F (79°C). >200°F (93°C).
1
This practice is under the jurisdiction of ASTM Committee D07 on Wood and is the direct responsibility of Subcommittee D07.07 on Fire Performance of Wood.
Current edition approved April 10, 2002. Published June 2002. Originally published as D6305-98. Last previous edition D6305-98
´1
Current edition approved Aug. 1, 2008. Published September 2008. Originally approved in 1998. Last previous edition approved in 2002 as D6305–02 .
2
Commentary on this practice is available from ASTM Headquarters. Request File No. D07–1004.
3
ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,[e-mail] Annual Book of ASTM Standards
, Vol 04.10.volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
D6305–08
4. Summary of Practice
4.1 ThetestdatadeterminedbyTestMethodD5516areusedtodevelopadjustmentfactorsforfire-retardanttreatmentstoapply
to un
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation:D6305–02 Designation: D 6305 – 08
Standard Practice for
Calculating Bending Strength Design Adjustment Factors
1
for Fire-Retardant-Treated Plywood Roof Sheathing
This standard is issued under the fixed designation D6305; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1
´ NOTE—The title for Table 6 was corrected from “One” to “Three Exposure Temperatures” in October 2002.
1. Scope
1.1 Thispracticecoversproceduresforcalculatingbendingstrengthdesignadjustmentfactorsforfire-retardant-treatedplywood
roof sheathing.The methods utilize the results of strength testing after exposure at elevated temperatures and computer-generated
thermalloadprofilesreflectiveofexposuresencounteredinnormalserviceconditionsinawidevarietyofcontinentalUnitedStates
climates.
1.2 Necessarily, common laboratory practices were used to develop the methods herein. It is assumed that the procedures will
be used for fire-retardant-treated plywood installed using appropriate construction practices recommended by the fire retardant
chemical manufacturers, which include avoiding exposure to precipitation, direct wetting, or regular condensation.
1.3 The heat gains, solar loads, roof slopes, ventilation rates, and other parameters used in this practice were chosen to reflect
common sloped roof designs. This practice is applicable to roofs of 3 in 12 or steeper slopes, to roofs designed with vent areas
andventlocationsconformingtonationalstandardsofpractice,andtodesignsinwhichthebottomsideofthesheathingisexposed
toventilationair.Theseconditionsmaynotapplytosignificantlydifferentdesignsandthereforethispracticemaynotapplytosuch
designs.
1.4 InformationandabriefdiscussionsupportingtheprovisionsofthispracticeareintheCommentaryintheappendix.Alarge,
2
more detailed, separate Commentary is also available from ASTM.
1.5 The methodology in this practice is not meant to account for all reported instances of fire-retardant plywood undergoing
premature heat degradation.
1.6This practice is written in inch-pound units with SI units provided in parentheses for information only.
1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
3
2.1 ASTM Standards:
D9Terminology Relating to Wood Terminology Relating to Wood and Wood-Based Products
D5516 Test Method for Evaluating the Flexural Properties of Fire-Retardant Treated Softwood Plywood Exposed to Elevated
Temperatures
3. Terminology
3.1 Definitions:
3.1.1 Definitions used in this practice are in accordance with Terminology D9.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 bin mean temperature—10°F (5.5°C) temperature ranges having mean temperatures of 105 (41), 115 (46), 125 (52), 135
(57), 145 (63), 155 (68), 165 (74), 175 (79), 185 (85), 195 (91), and 175°F (79°C). >200°F (93°C).
1
This practice is under the jurisdiction of ASTM Committee D07 on Wood and is the direct responsibility of Subcommittee D07.07 on Fire Performance of Wood.
Current edition approved April 10, 2002. Published June 2002. Originally published as D6305-98. Last previous edition D6305-98
´1
Current edition approved Aug. 1, 2008. Published September 2008. Originally approved in 1998. Last previous edition approved in 2002 as D6305–02 .
2
Commentary on this practice is available from ASTM Headquarters. Request File No. D07–1004.
3
ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,[e-mail] Annual Book of ASTM Standards
, Vol 04.10.volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
D6305–08
4. Summary of Practice
4.1 ThetestdatadeterminedbyTestMethodD5516areusedtodevelopadjustmentfactorsforfire-retardanttreatmentstoapply
to unt
...