O₂NE+ Oxygen Depletion Monitor

Applications: Laboratories, Medical, Food & Beverage, Farming
What is it:Oxygen (O) Depletion Monitor
Single / Multi-Gas Detector:Single
What it measures:Oxygen (O)
Portable / Fixed: Fixed

The ONE+ is a simple to use and maintain ambient oxygen (O) depletion monitor and sensor for use in laboratories which use inert gases and nitrogen (N₂)It is essential to monitor oxygen (O₂) depletion levels in laboratories where gases like argon (Ar), helium (He) and nitrogen (N₂) are used.

Any laboratory using inert gases such as argon (Ar), xenon (Xe), nitrogen (N), krypton (Kr), radon (Rn) or helium (He) need to consider the ONE+ oxygen depletion monitor.  This unique monitor will help you comply with applicable legislation for your laboratory.

Inert gases are used in laboratories to conduct experiments, in cryogenics and as carrier gases, but  they do not support human breathing. Inert gases are odourless, colourless and tasteless, making them undetectable without an oxygen monitor.

How it works

The ONE+ is an ambient oxygen (O₂) depletion monitor comprising of a wall mounted main sensor unit and a repeater. It is ranged from 0 to 25% and has 2 low audio/visual alarms. The sensor has a very long life and calibration is only required every 12 months and can be achieved using certified air.

Where to install?

The ONE+ oxygen depletion monitor is usually situated in laboratories that are using multiple gases to ensure that oxygen (O) levels do not deteriorate to an unsafe level. The unit is also sometimes used in the gas storage area where there is potential for a leak of helium (He) or nitrogen (N₂).

The ONE+ is installed in areas where an inert gas is being used or stored to provide a warning should the oxygen (Olevels deteriorate to an unsafe level. The repeater is located at the entrance to the room, highlighting the danger to personnel before they enter.

Let us take care of you, so you can take care of them.

Saving lives and rapid crisis response is at the heart of what we do. We design our systems in a way which enables you to focus on the job at hand, delivering the best possible care for your patients.

Did you know?

Most competitor O monitors have a 2 year sensor life. The O₂NE+ will last up to 7 years.

Part Numbers

Part Number: AX1BK10X55QXY01(O₂NE+ with UK Plug)
Part Number: AX1BK10X11QXY01 (O₂NE+ with EU Plug)
Part Number: AX1BK10X56QXY01 (O₂NE+ with US Plug)
Part Number: AX1BK10X20QXY01 (O₂NE+ with AUST Plug)


  • Long-life O sensor
  • User changeable sensor
  • Calibration adjustment of the ONE+ can be completed using ‘pure air’
  • Repeater included
  • Plug and play
  • Not cross sensitive to helium (He)
  • O range: 0.1 to 25%
  • Sensor accuracy: better than ± 0.75% O over 5.0 to 25.0% O
  • Response time (T90): <60 seconds
  • Operating temperature: 0 to +40 °C (+32 to +104 °F)
  • Temperature effect: 0.2% of reading/°C or 0.1115% of reading/ °F
  • Atmospheric pressure range: 811 to 1050 mbar absolute
  • Warm up time: 10 seconds to normal operation, prior to calibration allow 2 hours to achieve full accuracy
  • Dimensions: central unit = 175 x 105 x 75 mm, alarm repeater = 155 x 72 x 45 mm
  • Weight: central unit = 600g, alarm repeater = 150g
  • IP rating: IP65 for central unit and alarm repeater, unless the alarm repeater is quick connect then it is IP43
  • Sensor type: electrochemical cell
  • Sensor life: up to 7 years in air
  • Display: 4 digit LCD
  • Alarms: 2 x alarm visual indicators, 1 x system fault indicator, 1 x status indicator, common audible alarm
  • Alarm Sounder: min 75dBA
  • Relays: one or two optional alarm relays with changeover contacts assigned to alarm 1, alarm 2 or system fault.
  • Contact rating 240 V AC or 30 V DC at up to 2 A, contacts are non-latching fail-safe
  • Output: 2 wire, 4 to 20 mA (max load 150 Ω)
  • Power supply options: 210 to 250 V AC supply, 110 to 120 V AC supply, 9-24 V DC supply
  • ONE+ main unit and alarm repeater
  • User Manual
  • Test Certificate 
  • Rawl plugs & screws for wall mounting
  • Drilling template

    Any optional items ordered such as:
  • Additional alarm repeater's each with 9 metres of  interconnecting cable
  • Relay junction box

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