CO gas sensors have to fulfil the requirements of standards like the UL2034
or BS7860. Unfortunately, tin oxide gas sensors are also highly sensitive
to volatile organic compounds (VOCs) like long chain hydrocarbons, alcohols
or ethyl acetate. These standards require negligible interference in cross
-sensitivity tests of CO sensors. To fulfil the standards, charcoal filters
were used combined with a micromachined SnO2 sensor. The latter was operat
ed in a pulsed mode. Sensors with optimized size and material parameters of
the charcoal filters are shown to fulfil the UL2034. The sensors are chara
cterized by electrical measurements as required by these standards. The fil
ters are characterized by SEM, EDX, BET and TG/DSC. (C) 2000 Elsevier Scien
ce S.A. All rights reserved.