1.1 本试验方法适用于测定10μg/L至1000μg/L范围内的水中总碳（TC）、无机碳（IC）和总有机碳（TOC）。该方法适用于实验室或抓样应用，并已根据实践指南进行了实验室间研究 D2777 .试验方法 D5997 可用于在线测定。该试验方法利用过硫酸盐或有机碳的紫外线氧化，或两者结合CO 2. 选择性膜回收CO 2. 加入去离子水中。测量去离子水的电导率变化，并将其与氧化样品中的碳浓度相关。在没有氧化步骤的情况下以类似的方式测定无机碳。 在这两种情况下，样品都被酸化以促进CO 2. 通过膜回收。电导率测量与碳浓度之间的关系由一组CO化学平衡的化学计量学方程描述 2. ，HCO 3. – ，和H + ，以及离子浓度与电导率之间的关系。化学计量模型包括平衡常数和比电导的温度依赖性，从而导致该方法在所述TOC范围内的线性响应。参见测试方法 D4519 关于CO测量的讨论 2. 通过导电性。 1.2 这种测试方法具有非常高灵敏度的检测器的优点，该检测器允许对相对小体积的样品进行非常低的检测水平。 此外，使用两个测量通道可以确定CO 2. 在样品中独立于有机碳。CO将电导率检测器与样品隔离 2. 选择性膜导致非常稳定的校准，干扰最小。 1.3 该测试方法已成功用于掺入各种有机材料的试剂水。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。 1.4 除实验室分析外，本试验方法还可适用于在线监测。见试验方法 D5997 . 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 该试验方法用于测定各种天然、家庭和工业来源的水中的碳含量。 在最常见的形式中，该测试方法用于测量有机碳，作为监测核电、制药和电子等行业中使用的高纯度工艺水中有机杂质的一种手段。

1.1 This test method covers the determination of total carbon (TC), inorganic carbon (IC), and total organic carbon (TOC) in water in the range from 10 μg/L to 1000 μg/L of carbon. This method is for laboratory or grab sample applications and has been subjected to an interlaboratory study under the guidelines of Practice D2777 . Test Method D5997 can be used for on-line determinations. The test method utilizes persulfate or ultraviolet oxidation of organic carbon, or both coupled with a CO 2 selective membrane to recover the CO 2 into deionized water. The change in conductivity of the deionized water is measured and related to carbon concentration in the oxidized sample. Inorganic carbon is determined in a similar manner without the oxidation step. In both cases, the sample is acidified to facilitate CO 2 recovery through the membrane. The relationship between the conductivity measurement and carbon concentration is described by a set of chemometric equations for the chemical equilibrium of CO 2 , HCO 3 – , and H + , and the relationship between the ionic concentrations and the conductivity. The chemometric model includes the temperature dependence of the equilibrium constants and the specific conductances resulting in linear response of the method over the stated range of TOC. See Test Method D4519 for a discussion of the measurement of CO 2 by conductivity. 1.2 This test method has the advantage of a very high sensitivity detector that allows very low detection levels on relatively small volumes of sample. Also, use of two measurement channels allows determination of CO 2 in the sample independently of organic carbon. Isolation of the conductivity detector from the sample by the CO 2 selective membrane results in a very stable calibration, with minimal interferences. 1.3 This test method was used successfully with reagent water spiked with various organic materials. It is the user's responsibility to ensure the validity of this test method for waters of untested matrices. 1.4 In addition to laboratory analyses, this test method may be adapted to on line monitoring. See Test Method D5997 . 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 This test method is used for determination of the carbon content of water from a variety of natural, domestic, and industrial sources. In its most common form, this test method is used to measure organic carbon as a means of monitoring organic impurities in high purity process water used in industries such as nuclear power, pharmaceutical, and electronics.