ASTM F955-15(R2021) pdf free download

ASTM F955-15(R2021) pdf free download.Standard Test Method for Evaluating Heat Transfer Through Materials for Protective Clothing Upon Contact with Molten Substances
1. Scope
1.1 This test method covers the evaluation of materials’ thermal resistance to heat transfer when exposed to a molten substance pour. 1.1.1 This test method was validated using molten sub- stances of aluminum, brass, and iron. The test shall be permitted to be adapted for use with other substances. 1.2 This test method is applicable to materials from which finished primary protective apparel articles are made. 1.3 This test method does not measure the flammability of materials, nor is it intended for use in evaluating materials exposed to any other thermal exposure. 1.4 Use this test method to measure and describe the properties of materials, products, or assemblies in response to molten substance pour under controlled laboratory conditions and shall not be used to describe or appraise the thermal hazard or fire risk of materials, products, or assemblies under actual conditions. However, it is acceptable to use results of this test as elements of a thermal risk assessment which takes into account all the factors that are pertinent to an assessment ofthe thermal hazard of a particular end use. 1.5 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 appro- priate safety, health, and environmental practices and deter- mine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 8. 1.6 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
6. Apparatus
6.1 The test apparatus consists of four major components as follows: 6.1.1 An inclined specimen mounting and exposure board with two copper slug calorimeter thermal sensors and supports, 6.1.2 A pouring crucible and pouring mechanism, 6.1.3 A furnace for melting the test metal, and 6.1.4 Instruments for measuring test conditions and test results. 6.2 Sensor Construction: 6.2.1 Each copper slug calorimeter shall be 18 6 1 g, 40 mm diameter and 1.6 mm thick, and shall be constructed from electrical grade copper with a single 30 gage, iron/ constantan thermocouple wire and shall be installed as identi- fied in Fig. 1. 6.2.2 The exposed surface of each copper slug calorimeter shall be painted with a thin coating of a flat black high- temperature spray paint with an emissivity of 0.9. The painted sensor shall be dried before use and present a uniformly applied coating (no visible thick spots or surface irregularities). Note that an external heat source, for example, an external heat lamp, has been used to completely drive off any remaining organic carriers on a freshly painted surface. 6.3 Specimen/Sensor Board: 6.3.1 The specimen/sensor board shall be nominally 250 mm by 406 mm [10 in. by 16 in.] and fabricated ofa flame and heat resistant material with a thermal conductivity value of ≤0.15 W/m·K, high temperature stability, and resistance to thermal shock. The board shall be nominally 13 mm [0.5 in.] or greater in thickness. 6.3.2 The copper slug calorimeters shall be located in the centerline of the sensor board and mounted as shown in Fig. 1. The calorimeters shall be located 101 mm and 203 mm [4 in. and 8 in.] respectively, from the top of the board to the calorimeter centers as indicated in Fig. 2. 6.3.3 An attachment method shall be provided that affixes the test specimen to the board such that it covers both sensors and extends at least 25 mm [1 in.] beyond all edges. 6.3.4 The sensor board shall be inclined at an angle of 70° from horizontal. 6.3.5 The sensor board shall be located so that it meets the pour geometry illustrated in Fig. 2, where the molten substance is introduced at the centerline of the board. 6.4 Pouring Crucible—The pouring crucible shall be suit- able for the substance being poured and for handling tempera- tures up to at least 56 °C [100 °F] above the pouring tempera- ture. Crucible sizes appropriate for specific substances are shown in Table 1. The crucible shall be attached to a tilting mechanism capable of turning the ladle at the rate of one revolution per 4.7 6 0.2 s. The crucible shall be pivoted at a point 25 mm [1 in.] below the top of the crucible on the vertical. When tilted, the tilted action shall be stopped me- chanically after a rotation of10 6 5° from the vertical (Fig. 2). See also Annex A2.