Specifying a pressure vessel often stalls on one question: which certification actually applies? Buyers regularly see ASME, CRN, and PED grouped together in datasheets and tender documents, which suggests they are interchangeable. They are not. Each represents a different regulatory purpose, governing body, and geographic scope, and choosing the wrong pressure vessel code early can force redesigns, re-inspection, or rejection at the point of installation.
This article breaks down what each framework covers, when it applies, and how to decide which requirements belong in your procurement specification.
Certification frameworks confirm that the design, materials, fabrication, and inspection of a vessel meet a recognized safety standard before it goes into service. They also control market access: a vessel cannot legally operate in many jurisdictions without the right registration or marking, and insurers and authorities having jurisdiction rely on these credentials when approving installations.
Selecting the right pressure vessel code at the specification stage prevents the most expensive mistakes. A vessel built to one standard is often difficult and costly to adapt to another compliance framework because inspection requirements, documentation, and fabrication controls must be established during manufacturing.
The ASME Boiler and Pressure Vessel Code (BPVC) is the design and construction standard used across North America and widely referenced internationally. Section VIII covers pressure vessels specifically, defining rules for design calculations, material selection, welding, fabrication, and testing.
The U Stamp is a certification mark applied to vessels built in accordance with Section VIII, Division 1. It demonstrates that the manufacturer holds an ASME Certificate of Authorization and that the vessel was fabricated under a verified quality program.
The stamp also signals third-party oversight. An Authorized Inspector, independent of the manufacturer, reviews the work at defined hold points and signs off before the stamp is applied.
National Board (NB) registration records a stamped vessel in a central database, linking it to its Manufacturer’s Data Report for long-term traceability through inspections, repairs, and resale.
ASME-certified construction is commonly required for vessels installed in U.S. facilities, for equipment governed by state jurisdictional rules, and for projects where insurers or operators mandate code compliance. For most North American applications, ASME-certified pressure vessels are the baseline expectation.
A Canadian Registration Number (CRN) is issued when a pressure vessel design is reviewed and accepted by a provincial or territorial safety authority. Canada regulates pressure equipment at the provincial level, so a CRN confirms that a specific design is approved for use in a given jurisdiction.
Registration starts with a design review against CSA B51 and the applicable code. Each province and territory accepts registrations separately, though several recognize a design first registered in another jurisdiction. The resulting CRN identifier reflects where it was originally registered.
A CRN pressure vessel is required for any vessel operating in Canada above the regulated pressure and volume thresholds. A common procurement challenge is assuming ASME alone is sufficient for a Canadian site; the vessel still needs provincial registration before it can legally be placed in service.
The Pressure Equipment Directive (2014/68/EU) governs pressure equipment placed on the European Union market. PED compliance is demonstrated through CE marking, which indicates the equipment meets the directive’s essential safety requirements.
PED sorts equipment into risk categories (I through IV) based on pressure, volume, fluid group, and hazard. Higher categories trigger stricter conformity assessment modules and greater involvement from a Notified Body. Each category carries defined documentation and technical file requirements.
PED applies to equipment entering EU markets, including export projects and vessels manufactured elsewhere but installed in Europe. For international programs, PED requirements should be confirmed before fabrication, since the conformity route affects inspection and documentation throughout the build.
| Factor | ASME | CRN | PED |
|---|---|---|---|
| Primary Purpose | Design and fabrication standard | Provincial design registration | Market-access conformity |
| Geographic Scope | U.S. and international | Canada, by province | European Union |
| Governing Authority | ASME / state jurisdictions | Provincial safety authorities | EU directive / Notified Bodies |
| Required For | Code-mandated vessels | Vessels operating in Canada | Equipment sold in the EU |
| Documentation | Manufacturer’s Data Report | Registered design submission | Technical file, EU declaration |
| Inspection Requirements | Authorized Inspector hold points | Design review based | Module-dependent assessment |
| Registration Process | NB registration (optional/required) | Provincial CRN issuance | CE marking declaration |
| Common Industries | Oil and gas, power, processing | Energy, mining, processing | Chemical, food, manufacturing |
ISO 9001 certifies a manufacturer’s quality management system. It governs how a facility controls processes and consistency, but it does not certify any individual vessel. It complements code programs rather than replacing them.
EN 13445 is the European harmonized standard for unfired pressure vessel design. It provides a recognized route to satisfying PED’s essential requirements, much as ASME BPVC governs design in North America. The two standards use different design rules and are not directly interchangeable.
Yes. A vessel built to ASME Section VIII can also carry a CRN, and this is common for ASME-stamped equipment destined for Canadian sites.
No. They address different markets. A vessel may need ASME construction for North America and a separate PED conformity route for Europe.
It depends on the installation location. The destination jurisdiction, not the country of manufacture, usually determines the required certification.
Ask for the relevant Manufacturer’s Data Report, CRN identifier, or technical file and declaration, plus material and inspection records.
TRG Supply designs and fabricates pressure vessels to applicable codes while coordinating the compliance requirements that apply during fabrication. We maintain quality control processes, support the documentation buyers need for inspection and registration, and produce vessels that meet defined project specifications.
We do not act as a certification body or regulatory approval authority; those roles belong to authorized inspectors and jurisdictional authorities. Our role is compliance-focused production, from ASME pressure vessel solutions and other custom pressure vessels to industrial autoclave systems.
The three frameworks answer different questions. ASME establishes pressure vessel design and fabrication requirements. CRN governs Canadian provincial registration. PED applies to equipment entering European markets. Confirming the right pressure vessel code before fabrication avoids redesigns, procurement delays, and compliance risk.
If you’re scoping a vessel and want to confirm which requirements apply, contact TRG Supply to discuss your pressure vessel manufacturing requirements.
Contact us for more information on our products and how they can fulfill your manufacturing or sterilization needs. You may also ask us about our policies, ordering and delivery process, or for other related information.
Get In Touch