Amprobe CO2-100 [3475094] Handheld Carbon Dioxide Meter. The Amprobe CO2-100 is a Handheld CO2 Meter is designed to measure air quality compliance in occupied spaces such as offices, production floors, schools or hospitals. The portable CO2100 features Instant feedback with CO2 levels, with additional temperature and humidity measurement. The Amprobe CO2-100 measures CO2 up to 9999ppm and has a built in alarm warns against dangerous CO2 levels. The meter offers a triple display with simultaneous CO2, Temperature and relative humidity readings. The CO2100 has a high performace low drift sensor designed with NDIR waveguide technology. The large LCD display is easy to read and has a backlight function for use when working in dark areas.