# Which spare parts should a hospital keep for its gas network?

**Which spare parts should a hospital keep for its medical gas network, such as outlet valves, springs, seals and labels?**

In terms of reference for Honduran hospital oxygen networks (PDF dated June 2022), PAHO/WHO asked the contractor to hand over parts for one year of preventive and corrective maintenance after the warranty, such as pins, screws, springs, rubber seals, connectors, connector repair parts and labels; HTM 02-01 (2026) expects maintenance contractors to stock likely spares.

Two public documents show how spares for a medical gas network are handled: a buyer's tender requirement from PAHO/WHO and the maintenance chapter of NHS England's HTM 02-01. For the spares of a PSA oxygen plant, see [what spare parts a PSA plant should keep](https://library.ultracontrolo.com/answers/what-spare-parts-should-a-psa-plant-keep/).

## What one buyer asked for

In terms of reference for designing and installing oxygen networks in three hospitals in Honduras, PAHO/WHO asked the contractor to deliver, together with the installation, a set of parts needed for preventive and corrective maintenance for 1 year after the network's warranty period, giving as examples pins, screws, springs, rubber seals, connectors, connector repair parts and adhesive identification labels. The same document asked for a warranty of at least 1 year.

## Spares and replacements in HTM 02-01 (2026)

- Contractor stock: the maintenance contractor should keep a reasonable stock of spares for emergency call-outs, anticipating the spares most commonly required, and on large sites may hold that stock on site; each visit report lists the spares used.
- Contract terms: in the HTM's sample maintenance contract, spare parts are not included in the routine maintenance price, and minor repairs such as a leaking second-fix terminal unit are distinguished from other defects, which are reported to the Authorised Person (MGPS), who raises a repair order where appropriate.
- Safety valves: replaced every five years under a planned procedure; the line pressure relief device sits on a three-way cock so it can be exchanged for a certificated replacement.
- Hoses: pendant and bed-head hose assemblies are given a service life of five years and replaced within that period, because their condition cannot be judged by eye.
- Filters and adsorbents: pipeline filters are changed at the manufacturer's intervals, more often if wet or if the pressure drop exceeds the specification; vacuum bacteria filter elements usually annually or after a set number of hours; dryer desiccant and PSA molecular sieve at the supplier's intervals.
- Seals: damaged cylinder sealing washers and O-rings are replaced, with no more than one washer per interface, and the HTM's example manifold procedure checks the Bodok seal or O-ring at each cylinder change.
- Emergency supply kits: examined every year for damaged hoses and fittings, with components replaced as required.

## Outlet seals and cross-connection

HTM 02-01 warns that servicing older terminal units with interchangeable components may require isolating a ward. Where such work is done under a low-hazard permit, seals are replaced on one depressurised gas system at a time while the others stay pressurised, and the correct gas identity is finally confirmed with gas-specific proving tools and cross-connection tests. Suppliers should provide as-fitted drawings, circuit diagrams, valve charts and maintenance instructions, which the HTM treats as the foundation of the maintenance programme.

For its own systems, Ultra Controlo supplies original spare parts through UltraCare, its technical support programme of preventive and corrective maintenance and emergency support, 24 hours a day, 7 days a week.

### How often should medical gas hoses be replaced?

HTM 02-01 (2026) assigns hose assemblies in medical supply units a service life of five years and asks for them to be replaced within that period, because their condition cannot be judged by eye.

### Does a medical gas maintenance contract include spare parts?

Not in the HTM 02-01 (2026) sample contract, which excludes spare parts from the routine maintenance price; the HTM still expects the contractor to keep a reasonable stock of spares for emergency call-outs.

## Sources

- [PAHO/WHO, terms of reference for a contractor to design and install oxygen networks in three prioritised hospitals in Honduras (USAID ARP grant; PDF dated June 2022), Spanish](https://www.paho.org/sites/default/files/terminos_de_referencia_instalacion_de_redes_o2_proyecto_arp_0.pdf)
- [HTM 02-01 (2026) Part B, paragraphs 9.171, 11.91, 11.101, 11.107, 11.118, 11.120, 11.123, 11.129, 11.152, levels of hazard (chapter 7), cylinder handling, medical supply unit and vacuum plant tasks, and Appendix C sample contract, NHS England](https://www.england.nhs.uk/wp-content/uploads/2016/05/health-technical-memorandum-02-01-medical-gas-pipeline-systems-part-b-operational-management-aug-26.pdf)
- [Ultra Controlo, Medical gas answers: UltraCare (Industrial 2026 presentation, p. 22)](https://www.ultracontrolo.com/medical-gas-answers#what-is-ultracare)

Reviewed: 2026-10-23. Ultra Controlo engineering. https://library.ultracontrolo.com/answers/what-spare-parts-does-a-medical-gas-network-need/