1.1 本试验方法描述了苯酚二磺酸比色程序 ( 1. ) 2. 用于测定总氮氧化物[氧化亚氮（N 2. O） 燃烧和其他氮氧化过程产生的气体流出物除外。 1.2 它适用于二氧化氮（NO）等氮氧化物的浓度范围 2. )体积为5 ppm至数千ppm（每干标准立方米4至数千毫克）。 1.3 由于使用的抓取采样技术在很短的时间内采集相对较小的样本，因此获得的结果将是对氮氧化物的瞬时测量，因此，只有在气流充分混合且浓度随时间变化恒定的情况下，才会代表排放量。建议使用多个样本。 1.4 以国际单位制表示的数值应视为标准值。 括号中给出的值是英寸-磅单位的数学转换，仅供参考，不被视为标准值。 1.5 警告- 许多监管机构已将汞指定为一种危险物质，可导致严重的医疗问题。汞或其蒸汽已被证明对健康有害，并对材料具有腐蚀性。处理汞和含汞产品时应小心。有关更多信息，请参阅适用的产品安全数据表（SDS）。用户应意识到，法律可能禁止向您所在的州或国家销售汞和/或含汞产品。 1.6 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。 （有关更具体的安全预防信息，请参阅 8.5 和截面 3. .) ====意义和用途====== 5.1 本试验方法提供了一种测量总氮氧化物（NO）的方法 x )用于确定是否符合法规、研究各种减排程序对NO的影响等目的的气体排放量 x 并检查仪器测量的有效性。

1.1 This test method describes the phenol-disulfonic acid colorimetric procedure ( 1 ) 2 for the determination of total oxides of nitrogen [nitrous oxide (N 2 O) excepted] in gaseous effluents from combustion and other nitrogen oxidation processes. 1.2 It is applicable to a concentration range of oxides of nitrogen as nitrogen dioxide (NO 2 ) of 5 ppm to several thousand parts per million by volume (four to several thousand milligrams per dry standard cubic metre). 1.3 Since the grab sampling technique used takes a relatively small sample over a very short period of time, the result obtained will be an instantaneous measure of the nitrogen oxides and, therefore, will be representative of the emissions only if the gas stream is well mixed and the concentration constant with time. Multiple samples are recommended. 1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard. 1.5 Warning— Mercury has been designated by many regulatory agencies as a hazardous material that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Safety Data Sheet (SDS) for additional information. Users should be aware that selling mercury and/or mercury containing products into your state or country may be prohibited by law. 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 and health practices and determine the applicability of regulatory limitations prior to use. (For more specific safety precautionary information see 8.5 and Section 3 .) ====== Significance And Use ====== 5.1 This test method provides a means to measure the total nitrogen oxides (NO x ) content of gaseous emissions for purposes such as determining compliance with regulations, studying the effect of various abatement procedures on NO x emissions, and checking the validity of instrumental measurements.