1.1 本试验方法涵盖了一种现场测试水性尿素基柴油废气油液（DEF）浓度的技术，规定用于配备选择性催化还原技术的柴油发动机，其目的不是绕过或取代ISO 22241-2附件C中所述的通过折射率实验室法更准确地测定尿素含量。 1.2 本试验方法仅设计为定量试验，以确定DEF中的尿素浓度，其目的不是确定DEF的质量，也不是检测其中的微量或其他污染物。DEF的缩二脲含量在本试验方法中产生了已知偏差。 参见第节 9.2.1 详细信息。 1.3 单位- 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。 1.4 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、健康和环境实践，并确定监管限制的适用性。 1.5 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。

1.1 This test method covers a technique for field testing the concentration of aqueous urea-based diesel exhaust fluid (DEF) prescribed for use in diesel engines equipped with selective catalytic reduction technology and is not intended to circumvent or replace the more accurate determination of urea content by refractive index laboratory method, described in ISO 22241-2, Annex C. 1.2 This test method is designed solely as a quantitative test to determine the concentration of urea in DEF and does not purport to determine the quality of DEF nor to detect trace or other contaminants therein. Biuret content of DEF creates a known bias in this test method. See section 9.2.1 for details. 1.3 Units— The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. 1.4 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. 1.5 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.