System Sensor has released its NEMA 4-rated D4120W InnovairFlex watertight duct smoke detectors. The company says the detectors are built to operate in the most challenging conditions without the need for bulky or costly enclosures. These detectors can operate in airflow speeds from 100 to 4,000 ft per minute, temperatures from -4°F to 158°F, and humidity ranges from 0% to 95% (non-condensing). In addition, a watertight, UV-resistant housing provides protection against falling dirt, rain, windblown dust, splashing, and hose-directed water. InnovairFlex watertight models are compatible with all InnovairFlex accessories and include all the same features as the entire InnovairFlex line.