User Guide to Thresholds and Classification - Environmental ...

18User Guide for Thresholds and Classifications2.2. DefinitionsThe following terms are used in the Hazardous Substances (Minimum Degrees of Hazard) Regulations 2001and the Hazardous Substances (Classification) Regulations 2001 (the classification regulations) in respect ofexplosive substances.Termdeflagratedetonateeffective protectivefeatureggasJkgkPaLD 50liquidDefinitionIn relation to a substance that is initiated or ignited, means the production in thatsubstance of a chemical reaction that proceeds through, or along the surface of, thesubstance at subsonic velocity, where that chemical reaction:a. results in the steady production of hot gases at high pressures; andb. if the substance is sufficiently confined, results in an increase in pressure, rate ofreaction, and temperature that may produce a detonation of the substance.In relation to a substance that is initiated, means the production in that substance of achemical reaction that proceeds through that substance at supersonic velocity, resultingin the production of heat and a supersonic shock wave through the surroundingmedium.A device incorporated into an explosive article that will prevent accidental functioningduring normal conditions of transport, storage, or handling.gram(s)A substance that:a. is completely gaseous at 20 C and at 101.3 kPa absolute pressure; orb. has a vapour pressure of more than 300 kPa absolute pressure at 50 C.joule(s)kilogram(s)kilopascal(s)The median lethal dose, being a statistically derived single dose of a substance thatcan be expected to cause death in 50% of animals.A substance that isa. a substance that has a melting point of less than or equal to 20 C at 101.3 kPaabsolute pressure; orb. a viscous substance without a defined melting point, if:i. more than the quantity of the substance specified in ASTM D4359-90, called‗Test method for determining whether a material is a liquid or a solid‘, collectson a watch glass when tested in the manner specified in that test; orii. a penetrometer penetrates into the substance the distance defined in the testfor determining fluidity prescribed in Appendix A.3 of the European AgreementConcerning the International Carriage of Dangerous Goods by Road (UnitedNations, 1994), when the method specified in that test is followed.mmgmetre(s)milligram(s)January 2012 EPA0109