1.1 本试验方法涵盖了单乙二醇（1,2-乙二醇；MEG）在220区域波长下透射率的测定程序 nm至350 纳米。该结果提供了样品相对于紫外线（UV）吸收化合物的纯度的测量。 1.2 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。 1.3 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。 有关具体的危险说明，请参阅第节 7. . 1.4 查阅当前的安全数据表（SDS），了解有关本试验方法中使用的所有材料的毒性、急救程序和安全预防措施的详细信息。 1.5 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====== 4.1 需要了解乙二醇的紫外线透射率，以确定产品是否符合其质量规范的要求。 4.2 有机溶剂（如乙二醇）中的溶解氧形成络合物，将溶剂吸收从真空紫外线范围转移到可测量的紫外线范围（接近190 纳米至250 纳米）。MEG在180nm处具有UV吸收峰。对于MEG氧络合物，该峰移向更长的波长，从而增加了在220nm处的吸收能力。 4.2.1 然而，在水中没有观察到这种影响。由于水中的溶解氧在用于收集参考光谱之前需要氮气喷射，因此没有显著的可测量效果。 4.2.2 氮气喷射和在220 nm处重新测量可疑或边界乙二醇样品可作为排除或确认存在除氧气以外的紫外线影响污染物的工具。

1.1 This test method covers a procedure for the determination of the transmittance of monoethylene glycol (1,2-ethanediol; MEG) at wavelengths in the region 220 nm to 350 nm. The results provide a measure of the purity of the sample with respect to ultraviolet (UV) absorbing compounds. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 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. For specific hazard statements, see Section 7 . 1.4 Review the current Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safety precautions for all materials used in this test method. 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. ====== Significance And Use ====== 4.1 Knowledge of the UV transmittance of MEG is required to establish whether the product meets the requirements of its quality specifications. 4.2 Dissolved oxygen in organic solvents, such as MEG, forms complexes that shift the solvent absorption from the vacuum UV range into the measurable UV range (near 190 nm to 250 nm). MEG has a UV absorption peak at 180 nm. For MEG-oxygen complexes, this peak is shifted to a longer wavelength, thus increasing the absorbability at 220 nm. 4.2.1 However, this effect is not observed in water. There is no significant measurable effect due to dissolved oxygen in water that would require nitrogen sparging prior to using for collection of the reference spectrum. 4.2.2 Nitrogen sparging and re-measurement of suspect or borderline glycol samples at 220 nm can be used as a tool to rule out or confirm the presence of UV affecting contaminants other than oxygen.