UNDP REQ-OXY-001: requirements for oxygen plants

Status and scope

The document is number REQ-OXY-001, version V01, with an effective date of 1 January 2025 and a review date of 1 January 2028. It provides standard regulatory and technical considerations for procuring oxygen generator plants. PSA plants are prioritised, but most technical requirements also apply to VSA and VPSA systems. UNDP's procurement entity must share the document with suppliers and bidders as part of the solicitation process; the requirements below are what UNDP asks for in its procurement.

Regulatory requirements (section 5)

• Devices offered to UNDP must have market clearance under their classification. Where several laws apply, for example medical devices and pressure equipment, evidence of compliance with both is required; UNDP gives the PSA plant as an example of this.
• Table 1 classifies each main component and lists expected standards; the oxygen generator is classified as a medical device Class C and as pressure equipment. Apart from the piping, all PSA plant components must comply with ISO 15001 and be cleaned to ASTM G93 for oxygen compatibility.
• For medical devices, accepted routes include WHO prequalification and market clearance by listed regulators. For pressure equipment in the EU, UNDP refers to the Pressure Equipment Directive 2014/68/EU; for the USA, to ASME BPVC Section VIII. For oxygen cylinders in the EU, it refers to TPED 2010/35/EU.
• The declaration of conformity must follow the ISO/IEC 17050 format or the relevant regulations.
• Performance test reports for purity, flow and pressure must come from laboratories accredited by an ILAC member, which must be ISO 17025 certified, or from an EU notified body.
• Medical device manufacturing sites must comply with the current ISO 13485 or an equivalent quality system, and sites for products not classified as medical devices with the current ISO 9001 or equivalent; the bidder submits a risk management report to ISO 14971:2019 for medical device products.
• Markings: for EU pressure equipment, the CE marking followed by the notified body's number, plus design pressure, test pressure, nominal volume and other data; for cylinders under TPED, the Pi marking followed by the notified body's number and the next periodic inspection date.
• After award, any product change must be notified to UNDP QA immediately.

Technical requirements (section 6)

• UNDP describes oxygen generator plants as producing medical oxygen typically with 93% ±3% purity.
• The solicitation should include a P&ID, a 10-year lifespan guarantee and a 24-month warranty from the manufacturer, and a 3-year spare parts kit with part descriptions and costs.
• Pre-shipment inspection, performance tests (minimum three days of continuous operation), alarm tests and commissioning reports are required.
• Elevation, temperature, humidity and dust should be considered during design; the nitrogen discharge duct should be vented at least 3 metres from doors or windows and face downward.
• Maintenance services must include a warranty covering a minimum of two years.

Section 7 sets out the steps for establishing a PSA plant, from planning and assessment to sustainability. Annex II is a site evaluation form and Annex III a commissioning report for oxygen generator plants.

Points to watch

• For minimum specifications it refers to the WHO interim technical specifications for PSA oxygen plants of 8 June 2020. WHO's 2024 technical specifications state that their oxygen generator plant specification supersedes that 2020 interim guidance.
• Table 1 lists ISO 10461 for aluminium cylinder inspection and testing; ISO lists ISO 10461:2005 as withdrawn and as a predecessor of ISO 18119:2018.
• It cites the Global Fund and Build Health International briefing note on PSA, VPSA and VSA of 30 August 2023; the version now on the Global Fund resources site is dated 4 March 2025.