IEC/TR 62131-4:2011(E) reviews the available dynamic data relating to electrotechnical equipment transported by road vehicles. The intent is that from all the available data an environmental description will be generated and compared to that set out in IEC 60721. For each of the sources identified the quality of the data is reviewed and checked for self consistency. The process used to undertake this check of data quality and that used to intrinsically categorize the various data sources is set out in IEC/TR 62131-1.