TS EN 764-1

TS EN 764-1 is a terminology standard for pressure equipment, focusing on the basic terms and symbols used for pressure, temperature, volume and nominal size. It establishes a common technical language for pressure equipment addressed under European Directive 97/23/EC, covering vessels, piping, and pressure- and safety-related accessories in a unified vocabulary framework.

Why terminology matters in pressure equipment

In pressure equipment engineering, precise wording is not a formality: it affects design, documentation, inspection and operation. A terminology standard helps align how the main measurable quantities are named and symbolised so that calculations, ratings and descriptions are interpreted consistently across manufacturers, users and authorities. In general technical terms, pressure describes the force exerted per unit area, temperature influences material behaviour and process conditions, and volume expresses the capacity of a vessel or system.

What this part does and does not cover

This standard does not provide the units for the quantities it defines; those are covered elsewhere in the series. It also refers to diagrams in EN 764-7 for the relationships between the pressure-related quantities and their connection to pressure and safety accessories. As a result, TS EN 764-1 functions mainly as a foundational vocabulary and concept-setting document within the broader pressure equipment standards family.

• Defines basic terms and symbols for pressure equipment.
• Centers on pressure, temperature, volume and nominal size.
• Applies to vessels, piping, pressure equipment and safety accessories in general terminology.
• Leaves unit specifications to other standards in the series.