HTM-02 Standard of Hospital Liquid Oxygen Source VIE Plant Room

HTM-02 Standard

For hospitals with larger demands, a bulk medical oxygen VIE will generally be used. There is a nominal overlap of annual consumption between 27,500 m3 and 40,000 m3, where either a bulk VIE or a liquid cylinder installation could be considered, either to satisfy a particular requirement, or to accommodate possible site restrictions.

The liquid oxygen is stored at cryogenic temperatures (down to minus 183°C) and converted to a gas at ambient temperature by passing it through an air-heated vaporiser. Liquid oxygen provides a flexible approach to both the size and the choice of installation design.

The VIE system consists of:

• a vacuum-insulated cryogenic storage vessel to store the bulk liquid;

• one or more ambient-heated vaporisers to convert the cryogenic liquid into a gas for supply to patients via a pipeline;

• control equipment to control the pressure and flow of gas to the pipeline.

When considering the space requirements for the liquid oxygen compound(s), there may be operational advantages in having two compounds in different areas on the hospital site, rather than one larger site utilising either a single large vessel or multiple tanks.

Each supply system should be located in a secure fenced compound, which should be sized to allow adequate access to all of the control equipment. The site should essentially be level but designed to have adequate falls to prevent water accumulating beneath equipment.

The location of drains in the vicinity of the site should comply with the requirements specified in BCGA CP19 (see Table 23). Only under extreme conditions should the safety distances specified in BCGA CP19 be reduced.

The layout of the liquid oxygen installation should provide adequate access to all of the relevant components of the system and permit adequate airflow for the ambient vaporisers. The plinth should be of concrete construction. The area in front of the vessel(s) (tanker apron) should be non-porous concrete. Under no circumstances should tarmac be used in the vicinity of the liquid oxygen filling point, or areas where liquid oxygen spillage may occur.

The location of the liquid oxygen compound should permit the supplier to gain safe access with the appropriately sized tanker. It is the supplier's responsibility to assess the space requirements for vehicular access.

The design of the liquid oxygen installation should take into account the gas supplier's requirements for discharging the liquid oxygen from the cryogenic tanker. The area directly in front of the vessel should be kept clear to provide access for the delivery vehicle at any time. Under no circumstances should cars be permitted to park in front of the compound.