ASTM D8211-18

5.1 The autoignition temperature (AIT) of a gas mixture is the minimum temperature at which a gas mixture spontaneously ignites without an external ignition source. AIT is typically determined at atmospheric pressure, using small test vessels open to the atmosphere where gas is quickly injected into the test vessel and heated for a pre-determined time observing ignition or non-ignition (Test Method E659). AIT is often not directly applicable to real world conditions. Therefore, there is need for a test that determines if a gas or liquefied gas ignites or does not ignite when released onto a hot surface in a more unconstrained environment.

1.1 This test method covers a means for the discrimination between gases, which will ignite or not ignite when impinged on a hot surface when that surface is heated to 800 °C ± 5 °C (1472 °F) for a period of 2 min in a non-confined environment.

1.2 This test method may be applied to any non-pyrophoric substance that is a gas or liquefied gas at ambient temperature and pressure.

1.3 This test method should be used subject to the limitations that no single fire hazard property such as flash point, auto-ignition temperature (AIT), or the performance under the conditions of the present method shall be used to describe or appraise the fire hazard or fire risk of a material, product, assembly, or system under actual fire conditions. Fire hazard properties measured under controlled laboratory conditions may nevertheless be employed to describe properly the response of materials, products, assemblies, or systems under said controlled conditions. Properties measured under controlled laboratory conditions may be used as elements of hazard or risk assessment only when such assessments takes into account all of the factors that are pertinent to the evolution of the fire hazard of a given situation.

1.4 This standard is used to provide a quantitative measure of a gas’s or liquefied gas’s realistic surface ignition temperature in a non-quiescent environment.

1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.

1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.