This document specifies the requirements for the reconditioning, retesting and certification of Pressure Relief Valves (PRVs) for LPG pressure vessels covered under the scope of EN 14129. This document applies to retesting and reconditioning of PRVs that are carried out in a workshop and does not apply to site adjustment of installed PRVs. Annex A is an informative annex detailing a sampling approach for PRV requalification which is only used in case of on-site requalification of series produced pressure vessels fitted with series produced PRVs.