1、Designation: E2749 10 (Reapproved 2014)E2749 15 An American National StandardStandard Practice forMeasuring the Uniformity of Furnace Exposure on TestSpecimens1This standard is issued under the fixed designation E2749; the number immediately following the designation indicates the year oforiginal ad
2、option or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This standard provides general principles for measuring the uniformity
3、 of the furnace exposure on specimens tested inaccordance with Test Methods E119, E814, E1529, E1725, E1966 and E2336.1.2 This practice specifies the materials and the construction requirements for a standardized test specimen used to provide amounting surface for the instrumentation that measures f
4、urnace exposure.1.3 The instrumentation records temperatures, pressure differentials and oxygen content near the surface of the test specimen.1.4 The values stated in SI units are to be regarded as the standard. The units given in parentheses are for information only.1.5 This standard is used to mea
5、sure and describe the response of materials, products, or assemblies to heat and flame undercontrolled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials,products, or assemblies under actual fire conditions.1.6 Fire testing is
6、 inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting thesetests.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate sa
7、fety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C1396/C1396M Specification for Gypsum BoardE119 Test Methods for Fire Tests of Building Construction and MaterialsE176 Terminology of Fire StandardsE814 Test Met
8、hod for Fire Tests of Penetration Firestop SystemsE1529 Test Methods for Determining Effects of Large Hydrocarbon Pool Fires on Structural Members and AssembliesE1725 Test Methods for Fire Tests of Fire-Resistive Barrier Systems for Electrical System ComponentsE1966 Test Method for Fire-Resistive Jo
9、int SystemsE2336 Test Methods for Fire Resistive Grease Duct Enclosure Systems2.2 ISO Technical Report:ISO/TR 834-2 Fire resistance tests Elements of building construction Part 2: Guide on measuring uniformity of furnaceexposure on test samples3. Terminology3.1 DefinitionsFor definitions of terms us
10、ed in this practice, refer to Terminology E176.3.2 Definitions of Terms Specific to This Standard:3.2.1 effective area of the furnace openingfurnace opening within the boundaries of the monitoring instrumentation.1 This practice is under the jurisdiction of ASTM Committee E05 on Fire Standards and i
11、s the direct responsibility of Subcommittee E05.11 on Fire Resistance.Current edition approved April 1, 2014Jan. 1, 2015. Published April 2014February 2015. Originally approved in 2010. Last previous edition approved in 2010 as E2749-10.DOI:10.1520/E2749-10R14.DOI:10.1520/E2749-15.2 For referencedAS
12、TM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user
13、of an ASTM standard an indication of what changes have been made to the previous version. Becauseit 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 versionof the standard as p
14、ublished by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Summary of Practice4.1 This practice consists of preparing a standardized test specimen to represent test specimens describe
15、d in Test Methods E119,E814, E1529, E1725, E1966 and E2336. The standardized test specimen provides a low cost, easily constructed supportingconstruction for the mounting of instrumentation that measures the exposure imposed by the furnace onto test specimens.4.2 The standardized test specimen consi
16、sts of two layers of 15.9 mm (58 in.) thick Type X gypsum board on the surface facingthe furnace chamber attached to steel channels and a single layer of structural panels (plywood or oriented strand board) attachedto the steel channels on the surface away from the furnace chamber. The gypsum board
17、provides a fire-resistive surface for themounting of the instrumentation. The structural panels provide stability for the steel support channels.4.3 Instrumentation to measure the thermal impact due to exposure to the furnace upon the standardized test specimen isinstalled at various locations on th
18、e exposed surface of the standardized test specimen. Probes used to gather air samples withinthe furnace chamber are also installed.4.4 The standardized test specimen is exposed to the time-temperature curve specified in referenced ASTM fire test standardsfor a time period of 45 min during which tim
19、e data are recorded by the instrumentation mounted on the standardized test specimen.4.5 The data provide a record of the conditions and uniformity of the furnace exposure upon standardized test specimens. Thearea bounded by the instrumentation installed on the standardized test specimen is designat
20、ed as the effective area of the furnaceopening.5. Significance and Use5.1 This practice describes a procedure to gather data intended to measure the uniformity of exposure conditions upon testspecimens for the fire test methods described in Test Methods E119, E814, E1529, E1725, E1966 and E2336. The
21、 collected datafrom furnaces are intended to form a basis for performance requirements for the furnaces described in the referenced standards.5.2 This practice does not include requirements for furnace performance.5.3 In this procedure, the standardized test specimen is subjected to one or more spec
22、ific sets of laboratory test conditions. Ifdifferent test conditions are substituted or the end-use conditions are changed, it is not always possible by or from this procedureto predict changes in the fire-test-response characteristics measured. Therefore, the results are valid only for the fire-tes
23、t-exposureconditions described in this procedure.5.4 The attention of all persons connected with the conduct of this practice is drawn to the fact that fire testing is hazardous andthat there is a possibility that harmful smoke and gases are developed during the test. There is also a possibility tha
24、t mechanicaland operational hazards develop during the construction of the test specimen and the disposal of the test residues. An assessmentof all potential hazards and risks to health shall be made and safety precautions shall be identified and provided. Written safetyinstructions shall be issued.
25、 Appropriate training shall be provided to relevant personnel. Laboratory personnel shall ensure thatthey follow written safety instructions at all times.6. Apparatus6.1 The furnace(s) and restraining frame(s) used to conduct tests in accordance with Test Methods E119, E814, E1529, E1725,E1966 and E
26、2336 shall be used.6.2 Standardized Test Specimen:6.2.1 MaterialsThe materials used to construct the standardized test specimen shall consist of the following: gypsum board,structural panels, cold-formed steel supports and fasteners.6.2.1.1 The gypsum board shall be minimum 15.9 mm (58 in.) thick co
27、mplying with the requirements of Type X as defined inSpecification C1396/C1396M.6.2.1.2 The structural panels shall be minimum 18 mm (nominal 34 in.) thick. Typical materials include plywood and orientedstrand boards.6.2.1.3 The cold-formed steel joists for horizontal specimens shall be fabricated f
28、rom minimum 1.4 mm thick (0.055 in.) steel.The cold formed steel joists shall be “C” shaped having a minimum depth of 240 mm (912 in.), a minimum flange width of 40mm (158 in.) and a minimum lip length of 12 mm (12 in.).6.2.1.4 The cold-formed steel wall studs for vertical specimens shall be fabrica
29、ted from minimum 0.9 mm thick (0.035 in.) steel.The cold-formed steel wall studs shall be “C” shaped having a minimum depth of 90 mm (312 in.), a minimum flange width of30 mm (114 in.) and a minimum folded back return flange legs of 5 mm (14 in.).6.2.1.5 The cold-formed steel track channels for the
30、horizontal and vertical specimens shall be “C” shaped having a depthcompatible with the joists or wall studs being used.6.2.1.6 Steel fasteners used to attach the gypsum board to the studs shall be designed for the attachment of gypsum board tosteel supports. Typical screws have a thread diameter of
31、 5 mm (14 in.) and a head diameter of 8 mm (38 in.). The steel fastenersused to attach the inner layer shall have a minimum length of 25 mm (1 in.). The steel fasteners used to attach the exposed layershall have a minimum length of 40 mm (158 in.).E2749 1526.2.1.7 Fasteners used to attach the struct
32、ural panels to the studs shall be designed for the attachment of the panels to steelsupports.6.2.2 Construction MethodStandardized horizontal test specimen.6.2.2.1 The construction details with respect to the location of the joists, track channels, gypsum board and the structural panelsare shown in
33、Figs. 1-3. The construction details assume a furnace opening of 4.2 by 4.2 m (13 ft 938 in. by 13 ft 938 in.).Modifications to dimensions are necessary for other furnace openings.6.2.2.2 The steel joists shall be spaced 300 to 450 mm (1178 in. to 1734 in.) on center. The joists are inserted into the
34、 trackchannels. The use of steel clip angles are permissible to facilitate the attachment of the joists to the track channels.6.2.2.3 The inner layer of gypsum board shall be attached to the joists with the steel screws spaced a maximum of 200 mm (778in.) on center along each joist. A distance of 10
35、 to 15 mm (38 to 58 in.) shall be provided between the screws and the edges of thegypsum board.NOTE 1The inner layer, or base layer, of gypsum board is in contact with the joists.6.2.2.4 The exposed layer of gypsum board shall be attached to the joists with steel screws spaced a maximum 200 mm (778i
36、n.) on center along each joist and shall be spaced 100 mm (4 in.) from the screws used to attach the inner layer. A distance of10 to 15 mm (38 to 58 in.) shall be provided between the screws and the edges of the gypsum board.NOTE 2The exposed layer, or outside layer, of gypsum board is in contact wi
37、th the inner layer of gypsum board.6.2.2.5 The structural panels shall be attached to the joists with steel screws spaced a maximum of 150 mm (578 in.) on centeralong each joist. A distance of 10 to 15 mm (38 to 58 in.) shall be provided between the screws and the edges of the structuralpanels. Hole
38、s are permissible in the structural panels to facilitate the installation of the instrumentation.6.2.3 Construction MethodVertical Standardized Test Specimen:6.2.3.1 The construction details with respect to the location of the wall studs, track channels, gypsum board and the structuralpanels are sho
39、wn in Figs. 4-6. The construction details assume a furnace opening of 3.1 by 3.1 m (10 ft. 2 in. by 10 ft. 2 in.).Modifications to dimensions are necessary for other furnace openings.6.2.3.2 The wall studs shall be spaced 300 to 450 mm (1178 to 1734 in.) on center. The studs are inserted into track
40、channels.The use of steel clip angles are permissible to facilitate the attachment of the studs to the track channels.6.2.3.3 The inner layer of gypsum board shall be attached to the studs with the steel screws spaced a maximum of 200 mm (778in.) on center along each stud. A distance of 10 to 15 mm
41、(38 to 58 in.) shall be provided between the screws and the edges of thegypsum board.NOTE 3The inner layer, or base layer, of gypsum board is in contact with the studs.NOTE 1Dimensions in millimetres.Dimensions in millimetres.FIG. 1 Horizontal Standardized Test Specimen, Location of Joists and Track
42、 ChannelsE2749 1536.2.3.4 The exposed layer of gypsum board shall be attached to the studs with steel screws spaced a maximum 200 mm (778in.) on center along each stud and shall be spaced 100 mm (4 in.) from the screws used to attach the inner layer. A distance of 10to 15 mm (38 to 58 in.) shall be
43、provided between the screws and the edges of the gypsum board.NOTE 4The exposed layer, or outside layer, of gypsum board is in contact with the inner layer of gypsum board.6.2.3.5 The structural panels shall be attached to the support channels with steel screws spaced a maximum of 150 mm (578in.) on
44、 center along each support channel. A distance of 10 to 15 mm (38 to 58 in.) shall be provided between the screws and theedges of the structural panels. Holes are permissible in the structural panels to facilitate the installation of the instrumentation.NOTE 1Dimensions in millimetres.Dimensions in
45、millimetres.FIG. 2 Horizontal Standardized Test Specimen, Location of Inner Layer of Gypsum Board and Structural PanelsNOTE 1Dimensions in millimetres.Dimensions in millimetres.FIG. 3 Horizontal Standardized Test Specimen, Location of Outer Layer of Gypsum BoardE2749 1546.3 Furnace LimitationsFurnac
46、es with dedicated applications, such as testing of ceiling assemblies, typically have specifichorizontal or vertical assemblies for this purpose and therefore do not include open restraining frames.6.3.1 It is permissible to modify the standardized test specimen to account for these limitations.6.4
47、InstrumentationThe instrumentation installed on the standardized test specimen shall include plate thermometers, adirectional flame thermometer, bi-directional probes, Type K thermocouples and air sampling probes.6.4.1 The plate thermometers (1)3 shall be constructed as shown in Fig. 7.6.4.1.1 The p
48、late part of the plate thermometer shall be constructed from 150 61 mm long by 100 6 1 mm wide by 0.7 6 0.1mm thick nickel alloy plate strips folded to the design shown in Fig. 7.6.4.1.2 A Type K ungrounded Inconel4 sheathed thermocouple having a maximum diameter of 1 mm shall be fixed to thegeometr
49、ic center of the plate in the position shown in Fig. 7 by a steel strip made from the same material as the plate. The steelstrip shall be welded or screwed to the plate. The strip shall be 18 6 1 mm by 6 6 1 mm when it is spot welded to the plate (Fig.7) and 25 6 1 mm by 6 6 1 mm when it is to be screwed to the plate. The screw shall be a maximum 2 mm in diameter.6.4.1.3 The assembly of the plate and thermocouple shall be fitted with a pad of inorganic insulation material 97 6 1 mm by97 6 1 mm by 10 6 1 mm thick. The density
