Optical flame detectors are often used in highly polluted or dirty areas that force maintenance personnel to access the detector frequently and clean its optical window. The special Air Shield (Part no. 777161 for the 3600 Series), developed for 3600 optical flame detectors, allows their installation under tough environmental conditions where they may be exposed to oil vapors, sand, dust and other particulate matter.

The Air Shield allows connection of a continuous compressed air source, directed onto the detector `s external window, which prevents accumulation of dirt or dust on its optical surface. The installation of an Air Shield on the detector reduces the amount of maintenance and prolongs the time between maintenance/cleaning cycles.