本国际标准规定了在水介质中评估最终产品的方法 生物降解性，以及作为补充信息，主要生物降解性和从水中的完全消除 好氧微生物在给定浓度下产生的有机化合物。 本国际标准中描述的条件通常对应于允许 所选接种物在试验时间内发生的最大生物降解值。这些情况甚至可能会发生 比全规模污水处理厂更有利，尤其是如果其水力停留时间 活性污泥的年龄或适应性不是最佳的。 该方法适用于以下有机化合物: a） 在试验条件下使用的浓度下为水溶性，且预计不会转化为 不溶性代谢物，如果是生物降解而非仅消除，则应进行测定； b） 不挥发，或在试验条件下具有可忽略蒸汽压力； c） 不会因试验溶液起泡而损失； d） 在为试验选择的浓度下，对试验微生物无抑制作用。抑制作用可以是 使用合适的试验方法测定（例如，见ISO 8192）。 如果试验化合物有毒，则试验 必须降低浓度，或者可以使用预先暴露的接种物。 本国际标准也适用于生物降解和溶解气体消除的测量 废水中的有机化合物（在方法中也称为“试验化合物”）。 注:如果需要更多信息来预测处理厂中试验化合物或废水的行为，则 应进行模拟试验（如活性污泥模拟试验ISO 11733）。为了正确使用这种方法 其他生物降解方法见ISO 15462。

This International Standard specifies a method for the evaluation in aqueous medium of the ultimate biodegradability and, as additional information, the primary biodegradability and the total elimination from water, of organic compounds at a given concentration by aerobic microorganisms. The conditions described in this International Standard normally correspond to optimal conditions for allowing the maximum value of biodegradation to occur with the chosen inoculum in the test time. These conditions may even be more favourable than in full-scale wastewater treatment plants, especially if their hydraulic retention time, sludge age or the adaptation of the activated sludge is not optimal. The method applies to organic compounds which are a) water-soluble at the concentration used under the test conditions and not expected to be transformed to insoluble metabolites if biodegradation and not elimination only shall be determined; b) nonvolatile, or which have a negligible vapour pressure under the test conditions; c) not lost by foaming from the test solution; d) not inhibitory to the test microorganisms at the concentration chosen for the test. Inhibitory effects can be determined using a suitable test method (e.g. see ISO 8192). If the test compound is toxic, the test concentration must be lowered, or a pre-exposed inoculum can be used. This International Standard is also applicable to the measurement of biodegradation and elimination of dissolved organic compounds in wastewater (also called "test compound" in the method). NOTE If more information is required to predict the behaviour of test compounds or wastewater in a treatment plant, a simulation test (e.g. the activated sludge simulation test ISO 11733) should be performed. For appropriate use of this method and for alternative biodegradation methods, see ISO 15462.