Isocyanate detector is used for measuring vapor and aerosol levels of isocyanate compounds such as MDI, TDI, or HDI. It is housed in an environmentally sealed tamper resistant enclosure with an eternal membrane switch control panel. It operates on DC current from an external power supply and has internal battery backup. A large LCD on the detector indicates gas concentration and features a visual alarm that is triggered when a preset alarm level is exceeded. The LCD also shows self-diagnostic data such as unit readiness, alarm set level, battery current and charge voltage, percent of sampling tape remaining and fault situations.