We do not have a formal qualification for the number of hours our oxygen sensors will operate or mean time between failure calculations. We do however have a lot of experience in various fields and we know in boiler exhaust applications the sensor normally lasts for over 7 years. This is a very harsh environments with high temperatures, humidity and a variety of corrosive gases.
For clean aerospace applications, we have customers who require 87, 600 hours of operating life (10 years) and although it cannot commit to warranty that have purchased these oxygen sensors from us since 2008.