What is a medical gas ceiling pendant?

HTM 02-01 Part B, the NHS England guidance (2026 edition), lists booms and ceiling pendants among medical supply units, the category covered by ISO 11197:2019 for basic safety and essential performance. For a circular array of terminal units, for example on the underside of a pendant, HTM 02-01 uses the same order as a horizontal wall array, clockwise when viewed from below, with the AGS outlet allowed in the centre.

Fixed or multi-movement

• HTM 02-01 makes fixed pendants the default, to remove the need for flexible connections. A multi-movement pendant needs review by the Authorising Engineer (MGPS) and approval from the hospital's Medical Gas Safety Group.
• In movable pendants, hoses complying with BS EN ISO 5359 run from the terminal unit NIST through the unit to a female NIST in the ceiling, with minimal excess length; excess length can lead to kinking, twisting and increased pressure drop.
• Hoses are replaced every five years unless environmental conditions or the manufacturer's recommendations call for sooner replacement, and the replacement date is displayed on the outside of the pendant.
• A separate 600 mm x 600 mm access hatch close to the pendant is recommended for the ceiling NISTs.
• When planning operating-room pendants, the position of the operating luminaire and other ceiling devices is taken into account. With an ultra-clean ventilation (UCV) system, it may be more practicable to build the services into the UCV system; HTM 02-01 notes that this is particularly advantageous for surgical air, as rigid pipework avoids the pressure losses of flexible assemblies in pendants.

Brakes, electrics and maintenance

• Electrical brakes are preferred for moving pendants. Medical air should not power pendant control or braking systems; where pneumatic brakes are used, each pendant needs its own surgical air AVSU and flow control system.
• Electrical, communications and data services are kept together but separate from the pipelines, and unprotected live parts inside the pendant can be reached only with a tool.
• During quarterly tests, the probe must be free to rotate in a pendant or boom outlet, whereas it should not swivel in a wall outlet.
• Moving or replacing pendants with flexible hoses on NIST connectors is listed under high-hazard work in the permit to work system, as a case where a cross-connection hazard may arise.

Ultra Controlo supplies ceiling-mounted medical gas pendants for intensive care units, operating theatres and recovery rooms, with oxygen, air, vacuum and electrical services, and a pendant with a double swivel arm for theatres and intensive care bays.