MED : do not do a single work permit for big works. In ECH 15, we had one single work permit to change all pipes of E sector. It was difficult for our SSI to know excately on which equipment contractor was working. For PRD, we will ask them to not accept unaccurate work permits.
PRD : all lines where valves, mechanical items have to be dismantled, must be decommissioned. Becareful to by-pass lines, which can have been used several months and have not been decommissioned, becareful to sample valves !
PRD : open the drain to confirm line correct decommissioning before breaking line.
PRD : pressure test to be done systematically after each closing of circuit. All nuts to be installed back (incl. blind flanges).