Approved. For the purpose of this part, means equipment that has been listed or approved by a nationally recognized testing laboratory such as Factory Mutual Engineering Corp., or Underwriters' Laboratories, Inc., federal agencies such as United States Mine Safety and Health Administration or United States Coast Guard, which issue approvals for such equipment, or the department of labor and industries.

Closed container. A container so sealed by means of a lid or other device that neither liquid nor vapor will escape from it at ordinary temperatures.

Combustion. Any chemical process that involves oxidation sufficient to produce light or heat.

Fire brigade. An organized group of employees that are knowledgeable, trained, and skilled in the safe evacuation of employees during emergency situations and in assisting in firefighting operations.

Fire resistance. So resistant to fire that, for specified time and under conditions of a standard heat intensity, it will not fail structurally and will not permit the side away from the fire to become hotter than a specified temperature. For purposes of this part, fire resistance must be determined by the Standard Methods of Fire Tests of Building Construction and Materials, NFPA 251-72.

Flammable. Capable of being easily ignited, burning intensely or having a rapid rate of flame spread.

Flammable liquid. Any liquid having a flashpoint at or below 199.4°F (93°C). Flammable liquids are divided into 4 categories as follows:

(a) Category 1 includes liquids having flashpoints below 73.4°F (23°C) and having a boiling point at or below 95°F (35°C).

(b) Category 2 includes liquids having flashpoints below 73.4°F (23°C) and having a boiling point above 95°F (35°C).

(c) Category 3 includes liquids having flashpoints at or above 73.4°F (23°C) and at or below 140°F (60°C). When a Category 3 liquid with a flashpoint at or above 100°F (37.8°C) is heated for use to within 30°F (16.7°C) of its flashpoint, it must be handled in accordance with the requirements for a Category 3 liquid with a flashpoint below 100°F (37.8°C).

(d) Category 4 includes liquids having flashpoints above 140°F (60°C) and at or below 199.4°F (93°C). When a Category 4 flammable liquid is heated for use to within 30°F (16.7°C) of its flashpoint, it must be handled in accordance with the requirements for a Category 3 liquid with a flashpoint at or above 100°F (37.8°C).

(e) When liquid with a flashpoint greater than 199.4°F (93°C) is heated for use to within 30°F (16.7°C) of its flashpoint, it must be handled in accordance with the requirements for a Category 4 flammable liquid.

Flashpoint. The minimum temperature at which a liquid gives off vapor within a test vessel in sufficient concentration to form an ignitable mixture with air near the surface of the liquid, and must be determined as follows:

(a) The flashpoint of liquids having a viscosity less than 45 Saybolt Universal Second(s) at 100°F (37.8°C) and a flashpoint below 175°F (79.4°C) must be determined in accordance with the Standard Method of Test for Flash Point by the Tag Closed Tester, ASTM D-56-69, or an equivalent method as defined by WAC 296-901-14024, Appendix B-Physical hazard criteria.

(b) The flashpoints of liquids having a viscosity of 45 Saybolt Universal Second(s) or more at 175°F (79.4°C) or higher must be determined in accordance with the Standard Method of Test for Flash Point by the Pensky Martens Closed Tester, ASTM D-93-69, or an equivalent method as defined by WAC 296-901-14024, Appendix B-Physical hazard criteria.

Liquified petroleum gases, LPG, and LP gas. Any material which is composed predominantly of any of the following hydrocarbons, or mixtures of them, such as propane, propylene, butane (normal butane or isobutane), and butylenes.

Portable tank. A closed container having a liquid capacity more than 60 U.S. gallons, and not intended for fixed installation.

Safety can. An approved closed container, of not more than 5 gallons capacity, having a spring-closing lid and spout cover and so designed that it will safely relieve internal pressure when subjected to fire exposure.

Salamander. A portable heating device, solid or liquid fueled, which is not vented to the outdoor atmosphere.

Vapor pressure. The pressure, measured in pounds per square inch (absolute), exerted by a volatile liquid as determined by the "Standard Method of Test for Vapor Pressure of Petroleum Products (Reid Method)," (ASTM D-323-68).