This part of ISO 4491 specifies a method for the determination of the total oxygen content of metallic powders by reduction-extraction at high temperature.By agreement, this method is also applicable to the determination of the total oxygen content of sintered metal materials.The method is applicable to all powders of metals, alloys, carbides, and mixtures thereof which are non-volatile under the test conditions. The sample may be in powder or compact form.The analysis is carried out on the powder as supplied, but the method is not applicable if the powder contains a lubricant or binder. If such substances are present, the method may be used only if they can first be completely removed by a method not affecting the oxygen content of the powder.This part of ISO 4491 is to be read in conjunction with ISO 4491-1.