BS ISO 5145:2017 pdf free

BS ISO 5145:2017 pdf free.Gas cylinders一Cylinder valve outlets for gases and gas mixtures一Selection and dimensioning
ISO 14456 establishes a method of allocating to any gas or gas mixtures contained in cylinders a four-digit code (FTSC). This numerical code categorizes the gas or gas mixture in terms of its physical-chemical properties and/or flammability, toxicity, state of the gas (compressed gas and pressure rating,liquefied, etc.), and corrosiveness, as specified in ISO 14456. FTSC is the abbreviation of these properties.
For the purposes of this document, a gas mixture is defined as an intentional combination of two or more gases, which can be either in the gaseous phase or liquefied under pressure when in a gas cylinder.
NOTE This document does not attempt to identify gas mixtures which can be safely and satisfactorily prepared; this is the responsibility of the gas manufacturer. It does not describe any methods or techniques for preparing gas mixtures.
The principle of allocation of a FTSC code to gas mixtures is the same as that for single gases. The allocation of the FTSC code to a gas mixture, which allows the assignment of this mixture to one of the group of gases and gas mixtures (see ISO 14456), depends on the flammability, oxidizing ability,toxicity, and corrosiveness of the final mixture. For the determination of flammability and oxidizing ability, ISO 10156 shall be used, for toxicity, ISO 10298 shall be used, and for corrosiveness, ISO 13338 shall be used.
Mixtures containing spontaneously flammable gases (i.e. pyrophoric gases such as silane in ISO 14456:2015, Table 10) shall be considered as spontaneously flammable gas mixtures if the content of the pyrophoric gas(es) is more than 1,4 %.
The step index system comprises a double recess (faucet) into the valve outlet, into which a spigot of two different diameters is designed to fit (see the figure in Table 1). The lengths of the recesses and spigots are the same for each connection but the diameters vary depending on the group of gases for which the recess or spigot is designed. The form, dimensions, and tolerances are illustrated in Table 1,which provides 42 non-interchangeable connections.BS ISO 5145 pdf free download.