Compliance is non-negotiable for safety-critical components. For water supply projects, look for WRAS (UK), NSF/ANSI 61 (USA), or ACS (France) certifications to guarantee the materials are safe for drinking water. For general manufacturing quality, the supplier must hold ISO 9001 certification. Furthermore, ensure the valves meet EN 1171 or MSS SP-70 design standards, and that CE marking is provided if the goods are destined for the European Economic Area to satisfy the Pressure Equipment Directive (PED).