Standards Development

Scope

This document specifies design, type testing, marking and manufacturing test and examination requirements for ball valves used as:

a) closures of refillable transportable gas cylinders, pressure drums and tubes;

b) main valves for cylinder bundles;

c) valves for cargo transport units (e.g. trailers, battery vehicles and MEGCs);

which convey compressed gases, liquefied gases and dissolved gases.

NOTE 1 In the course of the document, the term "valve" is used with the meaning of "ball valve".

This document does not apply to:

• oxidizing gases as defined in ISO 10156,

• toxic gases (i.e. gases listed in ISO 10298 having an LC50 value ≤ 5 000 ppm) and

• acetylene for single gas cylinders, pressure drums and tubes.

NOTE 2 The reason for the exclusion of oxidizing gases is that the use of ball valves as closures of high pressure cylinders for oxidizing gases is known to lead to specific ignition hazards that cannot reasonably be mitigated through the ball valve design or type testing. Safety hazards concern both the ball valve itself and any downstream equipment.

This International document does not apply to ball valves for liquefied petroleum gas (LPG), cryogenic equipment, portable fire extinguishers and cylinders for breathing apparatus.

NOTE 3 Requirements for valves for cryogenic vessels are specified in ISO 21011 and at a regional level, e.g. in EN 1626. Requirements for valves for portable fire extinguishers at a regional level are specified e.g. in EN 3 series.

NOTE 4 Certain specific requirements for valves for breathing apparatus in addition to those that are given in this document are specified at a regional level, e.g. in EN 144 series. Certain specific requirements for quick-release valves for fixed fire-fighting systems in addition to those that are given in this document are specified in ISO 16003 and at a regional level e.g. in EN 12094–4.

Purpose

The work item for the development of the new standard for ball valve design and testing (ISO 23826) had to be cancelled and needs to be re-started with this proposal since modifications to the scope were believed to be necessary.

The new scope proposal is given above. The main difference of the scopes is that now specific gas services have been excluded in the scope due to safety considerations.