This document specifies the requirements for the installation and on-going quality assurance and quality control of data acquisition and handling systems (DAHS). This includes requirements on: installation (Clause 5) quality assurance and quality control during QAL2 (Clause 6) quality assurance and quality control during on-going operation (Clause 7) annual functional test (Clause 8) This document supports the requirements of EN 14181 and legislation such as the IED, MCPD and E-PRTR. It does not preclude the use of additional features and functions provided the minimum requirements of this European Standard are met and that these features do not adversely affect data quality, clarity or access.