1.1 本试验方法涵盖了在0.7 mg/L至20 mg/L范围内测定饮用水处理厂和经处理饮用水淡水来源光电化学需氧量的方案。更高的水平可通过样品稀释来确定。 1.2 光电化学需氧量通过使用二氧化钛（TiO）对样品进行光电化学氧化产生的电流来确定 2. )用发光二极管（LED）发出的紫外线照射。 1.3 本试验方法不需要使用危险试剂，如硫酸汞、重铬酸钾和硫酸银，这些试剂通常与化学需氧量的测定有关（即试验方法 D1252 ). 它还可以快速提供结果，因为样品不需要回流。 1.4 测定饮用水处理厂和处理后饮用水基质的淡水来源中的光电化学需氧量对于评估处理效果具有重要意义。光电化学需氧量可作为饮用水处理的关键目标——天然有机物的大量替代测量。在好氧生物处理过程中，测定光电化学需氧量可以估计微生物降解有机物所需的氧气。该测试方法是对现有天然有机物（NOM）监测技术的补充，并将通过快速需氧量测试帮助科学家和工程师进一步了解水中的NOM。 1.5 该试验方法已成功用于掺有纯化合物的试剂级水、饮用水处理厂的淡水源和经处理的饮用水。用户有责任确保本试验方法对未经试验基质的水的有效性。 1.6 本试验方法适用于可引入传感器的小于50µm的可氧化物质。 注1: 可以执行此测试方法( 1. )立即在现场或实验室使用未经处理的样品，以及( 2. )在实验室中，按照规定的保持时间，在适当保存的样品上。 1.7 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.8 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 有关具体的危险说明，请参阅第节 9 . 1.9 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本试验方法描述了一种快速测定水中杂质可能消耗的最大氧气量的方法。 如测试方法所述 D1252 化学需氧量通常用于监测和控制生活和工业废水中的有机和无机耗氧污染物。该光电化学需氧量测试方法专门用于测量饮用水处理厂和处理后饮用水基质的淡水源中的有机物和无机物。本光电化学需氧量测试方法不适用于家用和工业废水，以取代测试方法 D1252 . 5.2 本试验方法不需要使用与化学需氧量有关的危险试剂，如硫酸汞、重铬酸钾和硫酸银。 由于样品不需要回流，其结果也比化学需氧量更快。

1.1 This test method covers a protocol for the determination of the photoelectrochemical oxygen demand of freshwater sources for drinking water treatment plants and treated drinking water in the range of 0.7 mg/L to 20 mg/L. Higher levels may be determined by sample dilution. 1.2 Photoelectrochemical oxygen demand is determined using the current generated from the photoelectrochemical oxidation of the sample using titanium dioxide (TiO 2 ) irradiated with ultraviolet (UV) light from a light-emitting diode (LED). 1.3 This test method does not require the use of the hazardous reagents, such as mercuric sulfate, potassium dichromate and silver sulfate, that are often associated with the determination of chemical oxygen demand (that is, Test Methods D1252 ). It can also provide a result rapidly, as samples do not require reflux. 1.4 Determination of photoelectrochemical oxygen demand in freshwater sources for drinking water treatment plants and treated drinking water matrices has important implications for assessing treatment efficacy. Photoelectrochemical oxygen demand can be used as a bulk surrogate measure of natural organic matter, a key target for drinking water treatment. In aerobic biological treatment processes, determination of photoelectrochemical oxygen demand can provide an estimation of the oxygen required by microorganisms to degrade organic matter. This test method is complementary to existing natural organic matter (NOM) monitoring techniques and will help scientists and engineers further the understanding of NOM in water with a rapid oxygen demand test. 1.5 This test method was used successfully with reagent grade water spiked with pure compounds, freshwater sources for drinking water treatment plants and treated drinking water. It is the user’s responsibility to ensure the validity of this test method for waters of untested matrices. 1.6 This test method is applicable to oxidizable matter, <50 µm that can be introduced into the sensor. Note 1: This test method can be performed ( 1 ) immediately in the field or laboratory on an unpreserved sample, and ( 2 ) in the laboratory on a properly preserved sample following the stated hold times. 1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 9 . 1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 This test method describes a rapid method to determine the maximum quantity of oxygen that may be consumed by impurities in water. As outlined in Test Methods D1252 , chemical oxygen demand is typically used to monitor and control oxygen-consuming pollutants, both organic and inorganic, in domestic and industrial wastewaters. This photoelectrochemical oxygen demand test method is specific for measuring organics and inorganics in freshwater sources for drinking water treatment plants and treated drinking water matrices. This photoelectrochemical oxygen demand test method is not intended for domestic and industrial wastewaters to replace Test Methods D1252 . 5.2 This test method does not require the use of the hazardous reagents, such as mercuric sulfate, potassium dichromate and silver sulfate, that are associated with chemical oxygen demand. It can also provide a result more rapidly than chemical oxygen demand as samples do not require reflux.