CO/H2S-D2 Miniature Size Carbon Monoxide + Hydrogen Sulfide Sensor Introduction The world wide use of multigas, portable, personal safety monitors has grown since the 1970s to include an ever increasing number of industries. The one requirement in common to the majority of these instruments is the need to measure both Carbon Monoxide and Hydrogen Sulfide simultaneously. Alphasense now offers a compact, dual gas sensor which allows designers to reduce significantly instrument size and cost. The D2 sensor provides a unique approach to the dual gas sensor in both its size and working electrode configuration. The use of a high capacity filter over the Carbon Monoxide working electrode eliminates Hydrogen Sulfide cross sensitivity to Carbon Monoxide. Proven in the field over many years, these sensors perform well even under long term, challenging conditions.