The Oxygen Concentrator Directory

Testing mimicked varying environmental conditions including heat (20–40°C / 68–104°F), relative humidity (50–95%) and prolonged dust exposure.

Acceptable findings included:

• Oxygen concentration ≥ 82% (preferably ≥ 90%) over the full flow range, within 5 minutes of start.
• Flow accuracy: device flowmeter must match external test.
• Output pressure > 55 kPa (preferred > 137 kPa).
• Continued operation in environments up to 40°C and 50–95% relative humidity, including unpredictable duty cycles.
• Continued operation after prolonged dust exposure.
• Air intake not at the bottom; must have a gross particle filter and compressor intake filter.

• Oxygen concentration and flow rate should be stable throughout use.
• Devices should display delivered oxygen concentration in real time (e.g., green LED indicator).
• Alarms required if concentration falls below 82%, flow is occluded, or power is lost.
• Features that restrict overdraw are preferred.
• Electrical components should be double insulated with a circuit breaker or fuse.

• Devices should weigh < 27 kg, be stable against tipping, and have at least two casters.
• If warm-up time exceeds 2 min, unit should indicate when warm-up is complete.
• Noise should not exceed 60 dB at maximum flow (preferred < 45 dB).
• User manuals available in English, Spanish and French, included in box and on manufacturer's website.
• Filter changes should require no tools; cabinet filters should be washable.
• Settings readable from an angle and distance; controls durable and hard to bump inadvertently.

• Filters should be easy to access and remove; manuals must include cleaning/replacement instructions.
• Units should have ultrasonic oxygen sensors for reliability and longevity.
• Units should display total hours of operation.
• Units should be cleanable with standard hospital materials (e.g., bleach).
• Enclosure and internal components should not be excessively complex to remove; basic repairs should not require specialised tools.

• Units must comply with IEC 60601 and operate normally between −15% and +10% of rated voltage.
• Preferred: ability to perform under grave deviations from rated voltage (per WHO PQS benchmarks).
• Preferred: withstand exposure in 50 V increments up to 500 V and continue to operate.
• Units should protect against transient voltage surges up to 2 kV.

• Power efficiency must be ≤ 70 W / L/min.
• Preferred: soft-start feature to reduce in-rush current at start-up (advantage for solar-powered facilities).
• Preferred: power consumption scaling with flow rate; usage of < 40 W / L/min.