User Guide to Thresholds and Classification - Environmental ...

89User Guide for Thresholds and Classificationsmanufactured) is deemed to have a capacity to oxidise equivalent to the most hazardous element orcompound unless:a. it can be shown that the exact mixture itself has a different classification; orb. the EPA has previously determined that the mixture has, or falls within a range that has, an alternateclassification, in which case that classification applies.Where a substance has a defined range of compositions or mixtures it may fall into more than oneclassification step, according to the effect of different concentrations of the ingredients in the mixture.Screening procedures for substances that may be oxidising substancesOrganic compounds do not need to be considered against the criteria for oxidising substances if they do notcontain oxygen, fluorine, or chlorine, or if these elements are present in the compound but are chemicallybonded only to carbon or hydrogen.Inorganic substances do not need to be considered against the criteria for oxidising substances if they do notcontain any oxygen or halogen atoms.Classification for gasesThe UN Model Regulations do not classify gases further, having established the gas has an oxidisingproperty. The focus is principally on the carriage of the gas, typically under pressure, and the use of panlifecycle controls such as labelling to warn and otherwise inform people about safe handling.In line with the UN Model Regulations, the classification of oxidising gases translates into certain labellingand other hazard identification controls. For example, the UN Model Regulations require gases that areneither flammable (class 2.1) nor toxic (class 2.3) to be classified as class 2.2, and they may have asecondary hazard identification according to a test that can determine the gases ability to contribute tocombustion. For example, compressed oxygen is an oxidising gas and it has a United Nations classificationof class 2.2 (non-flammable, non-toxic gas) with subsidiary hazard class 5.1 (which indicates it is anoxidising substance).7.6. Organic peroxides – subclass 5.2If a substance meets any one of the threshold criteria described in the following sections, it is considered anorganic peroxide within the meaning of the HSNO Act.7.6.1. Threshold criteria for organic peroxides – subclass 5.2 (equivalent to UN division5.2)A substance is considered an organic peroxide, within the meaning of the HSNO Act, if any of the followingcriteria applies.January 2012 EPA0109