Insights · 2026-10-03

Pressure equipment, sorted by pressure rather than by product

The sorting here is finer than in the two preceding categories, and it starts from physical quantities rather than product names. The same vessel, at a different pressure or carrying a different medium, lands in a different category and takes a different module.

The starting point is a physical quantity, not a product name

Valve, pipe, vessel and heat exchanger tell you very little here. What decides the route are quantities: how dangerous the medium is, which the directive handles as fluid group, the maximum allowable pressure, the volume or nominal diameter, and the magnitude once they are multiplied.

That makes pressure equipment the category where one item can take different routes in different projects. A valve on a steam line and the same valve on a water line may fall into different categories. When the quote says only valve, the quote is missing the decisive criterion.

EU: four categories, each with its own set of modules

The EU basis is the Pressure Equipment Directive 2014/68/EU, which sorts equipment into categories I to IV by ascending level of hazard and sets out in Annex II which conformity assessment modules each category may use. What the text states directly is this: category I may use module A, internal production control; category II may use A2, D1 or E1 among others; and category IV corresponds to the combinations B plus D, B plus F, module G, or module H1, meaning type-examination with production quality assurance, or unit verification and full quality assurance on their own.

The sorting criteria are the fluid group combined with pressure times volume, or pressure and nominal diameter for piping. The actual reading has to be done row by row against Annex II, because the boundaries are given as a chart rather than a figure anyone can memorise.

One myth is worth killing here before it spreads. There is no (EU) 2024/68 amending the PED. The text in force is 2014/68/EU, and no such amending instrument appears in it.

Two side lines in the EU

Pressure equipment in the EU is not one line but three. Simple pressure vessels go under their own directive, 2014/29/EU, which covers mass-produced vessels of simple construction and states the conditions as a combination: the maximum working pressure does not exceed 30 bar and the product of that pressure and the vessel's capacity does not exceed 10 000 bar·L, with a lower bound of 0.5 bar also set. These vessels are low risk and made in volume, so the route is lighter than the PED.

Transportable pressure equipment goes under 2010/35/EU, aimed at cylinders and tank containers, and its distinguishing feature is that it has to line up with the rules for transporting dangerous goods. The assessment therefore happens not only at the factory but also in transport.

The boundary between the three lines is worth remembering. A given item normally falls under exactly one of them, and picking the wrong line is worse than failing a test, because the entire route changes with it.

US: a stamp and state law

There is no federal pressure equipment admission act in the US. The obligation comes from two places: the ASME Boiler and Pressure Vessel Code becomes legally binding once adopted by a state's pressure equipment law, and each state runs its own in-service inspection regime. The equipment carries an ASME stamp, with symbols such as U, U2 or S depending on the type, and inspection is done by an ASME authorised inspector.

The practical meaning is the same as in the machinery and PPE articles. US compliance is a chain built from state law and an industry code, not a federal mark. What a buyer checks is the stamp and the documents behind it, not a certificate.

For this section we hold the regime only; this library has not collected the ASME code itself, which sits in the paid standards layer.

China: the licence route

The decisive instrument in China is not a product standard but the special equipment regime. Fixed pressure vessels, boilers and pressure piping are special equipment, and manufacturing them requires a special equipment manufacturing licence, along with type testing and supervised inspection under the safety technical regulations, with a Chinese licensed body involved. Standards such as GB 150 are design and manufacturing standards; they are not the admission licence.

The distinction matters to a foreign buyer. A factory saying it works to GB 150 has answered a manufacturing standards question. Exporting to China, or using the equipment inside China, raises the manufacturing licence question. Both exist, and one does not stand in for the other.

Japan, Korea, Brazil, Australia-NZ, Gulf

Japan regulates under its industrial safety and health act and the high pressure gas safety act, with vessels split into first and second class and subject to inspection. Korea works through its high pressure gas safety management act and energy use rationalisation act, with KGS standards and inspection. Brazil has NR-13 on steam boilers and pressure vessels alongside INMETRO certification. Australia and New Zealand use AS 1210, AS/NZS 3788 for in-service inspection, and AS 2593. The Gulf states regulate under the GSO pressure equipment technical regulation, with Saudi Arabia routing through SABER.

For these markets we currently hold the regime described but no primary text, so the page states the regime and no document numbers.

Ten markets side by side

Two columns, what does the sorting and where the obligation comes from:

The third column is the one worth reading. In the EU and China the obligation lands on a licence or certification; in the US it lands on an industry code adopted by state law. The first gives you a certificate; the second gives you a stamp and a file. A buyer who approaches the US market looking for a certificate will usually not find one.

What to ask before you order

Ask five things about pressure equipment: the medium and its fluid group, the design pressure, the volume or nominal diameter, which category that puts it in, and which module that category allows. The first three are the cause and the last two the effect. A supplier that jumps straight to a category without the first three is guessing.

Then two more: who holds the certificate or the stamp, since both follow a legal entity rather than a production line, and who performs in-service inspection, which is routinely forgotten in cross-border purchasing and yet meets the equipment again once it is installed. To work through these in order, start with the free verification checklist. The previous article in this series is personal protective equipment; the next, construction products, covers a different basis again, where what is declared is performance. To see how certifications and licences are recorded, look at a report sample, or get in touch.