Oxygen Sensors (O2)

Oxygen Sensors (O2)

Oxygen makes up 21% of the atmosphere by volume. This is halfway between 17% (below which breathing for unacclimatised people becomes difficult) and 25% (above which many organic compounds are highly flammable). The element and its compounds make up 49.2% by mass of the Earth’s crust and about two-thirds of the human body.


Accurate measurement of Oxygen is core to Alphasense’s portfolio, whether it’s required for safety, medicine, air quality or specialist processes.

Alphasense Oxygen Sensors (O2 sensors) have proved the test of time as cost-effective, low cost and robust in various applications. Unlike partial pressure oxygen sensors, our design has good pressure and temperature dependence, making it the best choice for safety applications. Our lead-free oxygen sensor range has a significantly increased lifetime over a lead-based sensor – minimising the likelihood of sensor leaks and making mid-contract servicing a thing of the past.

Alphasense Oxygen Sensors

Our oxygen sensors are available in three sizes:


A: 20mm diameter, the industry-standard size for portable gas detectors
C: 20mm diameter, extra height allows additional filter material when measuring combustion gases
G: Miniature, proven long-term performance. The sensors are designed for the next generation of portable gas detectors. Part of the Alphasense ‘D’ family.

Benefits of Oxygen Sensors

Enhanced safety

Oxygen sensors are pivotal in industrial environments, where they continuously monitor oxygen levels to ensure worker safety. Detecting low oxygen levels is crucial as it helps prevent potential health hazards and reduces the risk of fires or explosions.

Environmental monitoring and control

Oxygen sensors are vital components in environmental monitoring systems, playing a crucial role in assessing oxygen levels in air and water. This capability aids in gauging pollution levels, maintaining aquatic ecosystems, and understanding the impact of human activities on the environment.

Critical role in healthcare

In the medical field, oxygen sensors are integral to devices like pulse oximeters. These sensors accurately measure oxygen saturation levels in patients’ blood, facilitating effective monitoring during surgeries, for patients with respiratory conditions, and those undergoing oxygen therapy.

Application notes

Download Oxygen Application Notes – see application notes for full details.

Sensor Specification Summary

Compare Alphasense Oxygen sensors – sensor specification summary.

Data Sheets
File Description Type
O2-G2 Low profile, 2 year Data Sheet Download
O2-G1 Low profile, 1 year Data Sheet Download
O2-C2 Combustion, 2 year Data Sheet Download
O2-A3 Small, 3 year Data Sheet Download
O2-A2 Small, 2 year Data Sheet Download
O2-A1 Small, 1 year Data Sheet Download
LFO2-A4 Lead Free, long life Data Sheet Download