1.1 本试验方法适用于水中5个浊度单位（NTU）下浊度的在线测量。 1.2 用户有责任确保该测试方法对未经测试的基质水的有效性。 1.3 在本试验方法中，校准标准以NTU值定义，但假定其他指定的浊度单位是等效的。 1.4 该测试方法将可追踪的报告单位分配给用于执行测量的相应技术的类型。单位在数值上与校准标准相当。例如，1 NTU的甲嗪标准也等于1 FNU（甲嗪浊度单位）标准、1 FNRU（甲嗪比浊单位）标准等等。 1.5 以国际单位制表示的数值应视为标准。 本标准不包括其他计量单位。 1.6 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 饮用水、工厂废水、食品和饮料加工用水以及大量其他水的浊度是不可取的- 依赖的制造过程。悬浮物的去除通过混凝、沉淀和过滤来完成。浊度的测量提供了一种快速的过程控制方法，以确定何时、如何以及在多大程度上必须对水进行处理以满足规范要求。 5.2 该测试方法适用于在线监测饮用水、工艺水和高纯度工业用水中的浊度。 5.3 所使用的仪器必须允许对样品流进行连续在线监测。 注1: 看见 8.2 用于讨论由气泡引起的信号尖峰。 5.4 在报告测量结果时，还应报告适当的单位。这些单位反映了用于生成结果的技术，如有必要，可以提供与历史数据集更充分的比较。 5.4.1 表1 描述了技术和报告结果。列出的那些技术适用于本试验方法中规定的测量范围，尽管也可能提供其他技术。 5.4.2 对于中报告范围之外的特定设计 表1 ，应使用下标波长值以浊度单位（TU）报告浊度，以表征所使用的光源。

1.1 This test method is applicable to the on-line measurement of turbidity under 5 nephelometric turbidity units (NTU) in water. 1.2 It is the user's responsibility to ensure the validity of this test method for waters of untested matrices. 1.3 In this test method calibration standards are defined in NTU values, but other assigned turbidity units are assumed to be equivalent. 1.4 This test method assigns traceable reporting units to the type of respective technology that was used to perform the measurement. Units are numerically equivalent with respect to the calibration standard. For example, a 1 NTU formazin standard is also equal to a 1 FNU (formazin nephelometric units) standard, a 1 FNRU (formazin nephelometric ratio units) standard, and so forth. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 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 Turbidity is undesirable in drinking water, plant effluent waters, water for food and beverage processing, and for a large number of other water-dependent manufacturing processes. Removal of suspended matter is accomplished by coagulation, settling, and filtration. Measurement of turbidity provides a rapid means of process control to determine when, how, and to what extent the water must be treated to meet specifications. 5.2 This test method is suitable for the on-line monitoring of turbidity such as that found in drinking water, process water, and high purity industrial waters. 5.3 The instrumentation used must allow for the continuous on-line monitoring of a sample stream. Note 1: See 8.2 for discussion on signal spikes resulting from bubbles. 5.4 When reporting the measured result, appropriate units should also be reported. The units are reflective of the technology used to generate the result, and if necessary, provide more adequate comparison to historical data sets. 5.4.1 Table 1 describes technologies and reporting results. Those technologies listed are appropriate for the range of measurement prescribed in this test method are mentioned, though others may come available. 5.4.2 For a specific design that falls outside of the reporting ranges in Table 1 , the turbidity should be reported in turbidity units (TU) with a subscripted wavelength value to characterize the light source that was used.