ETSI TR 101 550列出了欧洲公共采购ICT产品和服务的可访问性要求EN 301 549[i.3]创建过程中使用的文件，并为实施该文件中规定的测试程序所需的任何其他文件提供了来源参考。除了确定EN内容的来源外，本文件还提供了额外的解释，以帮助EN用户澄清和支持有关测量方法的信息，尤其是在目前没有全球认可的测试的情况下。如果存在任何测试差距，则应确定这些差距，并制定测试描述和评估方法。 在不可能做到这一点的特殊情况下，就如何填补空白提出了建议。

ETSI TR 101 550 lists the documents used in the creation of EN 301 549 [i.3] on accessibility requirements for public procurement of ICT products and services in Europe and provides a source reference for any other documents needed to implement the test procedures specified in that document.As well as identifying the sources for the EN content, the present document also provides additional explanation to assist users of the EN with clarifications and supporting information about measurement methods, particularly where no globally agreed test presently exists.Where there are any test gaps, these are identified and test descriptions and evaluation methodologies are developed. In those exceptional cases where it is not possible to do so, recommendations are given on how the gaps should be filled.