Mike, The Par. 3.1.2, Permanent Joining of the PED, states that "For Pressure Equipment in categories II, III and IV, operating procedures and personnel must be approvbed by a competent third party which at the manufacturer's discretion may be a: notified body, or a 3rd party organization recognized by a Member State ....."
For Category I equipment, and for equipment below the pressure / diameter limits of Category I, third party approvals are not required.
So you would need to know the category of the equipment you are working on. Regards, Sol.