The CO2 detector in the A50 uses infrared technology and is designed not to require regular servicing. This is because sensor life characteristics are programmed into each CO2 sensor individually, and why we are able to offer a 5-year warranty on the sensor. Every A50 system should be calibrated up to the laws and regulations in the state or country of the customer. Any issues with the A50 functionality would be indicated by the fault light (and associated alarm). 

Customers and maintainers can carry out 'Proof tests' by passing alarm gases over the sensor to check that alarms trigger correctly.

For systems that are fitted with an O2 sensor further servicing will be necessary. 

The O2 sensor fitted to the A50 CO2/O2 uses electrolytic technology and will deplete with time and exposure to oxygen. It is therefore necessary to not only 'Proof test' the sensor regularly, but also to carry out calibration adjustments bi-annually (at least). These cells should also be replaced once calibration adjustment is no longer possible. 

This service should be carried out by trained and certified field service technicians.