Oxygen is the most widely used medical gas in any hospital, and the way it is supplied shapes the design of the whole medical gas system. Broadly, there are three options: liquid oxygen stored in a bulk tank, oxygen produced on site by a concentrator plant, or high-pressure cylinders connected to a manifold. Many hospitals combine two or more. This guide compares the options to help planners and contractors understand the trade-offs.
1. Liquid oxygen (bulk tank)
Liquid oxygen is stored in an insulated bulk tank, often called a vacuum insulated evaporator, at very low temperature. As oxygen is needed, the liquid passes through vaporisers that warm it into gas, which then feeds the pipeline through pressure control equipment. A specialist gas company refills the tank by road tanker.
Advantages: very high storage capacity in a compact footprint, high-purity medical oxygen, and well suited to large hospitals with high, steady demand.
Considerations: depends on regular deliveries and road access, requires a suitable outdoor compound with safety distances, and usually involves a supply contract with a gas company.
2. Oxygen concentrator plant (PSA)
An on-site oxygen plant uses pressure swing adsorption (PSA). Compressed air passes through vessels filled with a material that adsorbs nitrogen, leaving oxygen-enriched gas, typically around 93 percent oxygen. The plant includes air compressors, dryers, filters, adsorption vessels, a receiver and monitoring equipment.
Advantages: the hospital produces its own oxygen, reducing dependence on deliveries, which is valuable in remote areas or where supply chains are unreliable. Running costs are mainly electricity and maintenance.
Considerations: needs reliable power and regular maintenance, and the oxygen concentration is lower than liquid oxygen. Whether this concentration is acceptable depends on local pharmacopoeia rules and regulations, which should be checked at design stage.
3. Cylinder manifolds
High-pressure cylinders are connected in banks to a manifold with a control panel that reduces the pressure and switches automatically from an empty bank to a full one. Cylinders are exchanged by the gas supplier or the hospital’s own team.
Advantages: simple, low capital cost, flexible and easy to expand, and ideal for small hospitals, clinics and nursing homes.
Considerations: labour-intensive for high demand, needs space for full and empty cylinder storage, and requires careful stock management.
Comparing the options
- Large hospitals with high demand: liquid oxygen as the primary supply is common, with cylinder manifolds as backup.
- Medium hospitals and remote facilities: PSA plants are often attractive, especially where deliveries are difficult.
- Clinics and small facilities: cylinder manifolds are usually the most practical choice.
Always plan for backup
Whatever the primary source, medical gas standards require secondary and emergency reserve supplies so that oxygen is never interrupted. A typical arrangement combines a primary source, a secondary source that takes over automatically, and an emergency reserve manifold, often with cylinders. Alarms warn staff when the system switches to a backup source or when reserves run low.
Beyond the source
The source is only the start. Oxygen then travels through medical grade copper pipework, area valves and alarms to terminal units, where clinicians use regulators, flowmeters and other devices. All of these must be sized and specified to match the chosen source and the hospital’s demand.
Questions to settle early
- What is the expected peak and average oxygen demand?
- How reliable are local deliveries and power supply?
- What purity do local regulations require?
- Where can the plant, tank or manifold room be safely located?
Safety around oxygen sources
Oxygen itself does not burn, but it makes other materials burn far more fiercely. Keep plant rooms and compounds free of oil, grease and combustible materials, and display clear no-smoking signs.
Supplying your project
Nefton Exports Industries supplies control panels, regulators, flowmeters, copper tubes and fittings for hospital oxygen systems. Talk to us about your project.
