The Pressure Equipment Directive (PED) 97/23/EC applies to the design, manufacturing and conformity evaluation process of Pressure Equipment, as well as Pressure Equipment Assemblies. The maximum allowable pressure must be greater than 0.5 bar.

According to the directive, pressure equipment is defined as vessel, piping, safety and pressure accessories. The general term "Pressure Equipment" covers pressure vessels, steam boilers, heat exchangers, tubing (pipe) and safety and pressure accessories, as well as devices under pressure. Also included are all parts and products that are attached to pressurized parts (i.e., flanges, nozzles, lifting parts, fast-connectors, etc.)

According to Article 20, the PED is applicable since November 29, 1999, with a transitional period until May 29, 2002. Until then, manufacturers and the final users of pressure equipment can decide if the product shall meet the PED requirements or the national pressure vessel code requirements of the country where the product will be put into service (e.g. German Pressure Vessel Code).

Products covered include:

• Pressure Vessels
• Heat Exchangers
• Pressure Gas Cylinders
• Steam Boilers
• Pipeline Equipment
• Storage Tanks
• Pressure Relief Devices
• Valves, Regulators, etc.
• and more

When pressure equipment meets the requirements imposed in the Pressure Equipment Directive (97/23/EEC), the CE Mark shall be affixed to such equipment. The "way" to the CE Marking is outlined in Article 10 and Annex III of the directive. This is called the Conformity Assessment.

The flowchart shows possible activities involved in the conformity assessment procedure.

1. Facility Certification
2. Design Analysis and Approval
3. Welding Procedure Approval *
4. Welding Operator Certification *
5. Material Testing and Certification
6. Final Equipment Inspection & Certification

*note: depending on product type and category