In addition to EN 13850:2002 Postal Services - Quality of Service - Measurement of the transit time of end-to-end services for single piece priority mail and first class mail, this European Standard specifies methods for measuring the end-to-end transit time of domestic and cross-border non-priority single piece mail, collected, processed and distributed by postal service operators. It considers methods using a representative end-to-end sample of all types of single piece addressed letter mail.