Lead oxygen sensors (galvanic cells) exhibit significant responses to changes in air pressure.

Lead oxygen sensors (galvanic cells) exhibit significant responses to changes in air pressure.

Common 2-electrode lead-containing oxygen sensors (galvanic cells), when subjected to sudden increases in air pressure, will show rapid current signal amplification. Well-known sensors of this type include CITY 4OXV, Alphasense O2-A2, DD S+4OX, and other oxygen sensors operating on the same principle.

For detection instruments using such sensors, when subjected to sudden shaking, dropping, blocked sensor air inlets, or obstructed exhaust ports (in pump-suction type devices), the O2 readings typically surge rapidly to 23-30% vol, triggering high oxygen alarms. This phenomenon is not indicative of sensor quality issues. After waiting 10-20 seconds for air pressure stabilization around the sensor, the instrument readings will return to normal levels.

Some high-end detection instruments account for the pressure characteristic curve of oxygen sensors and incorporate correction coefficients during signal processing, which can effectively mitigate such interference phenomena.