Andover Protection Systems makes two lines of equipment for hazardous environments. It makes more than 1000 models of "explosion-proof" compressors for refrigeration and air-conditioning products. In addition, APS offers hazardous-duty Air-Cleaning Blowers^TM (ACBs) that blow and clean air without the use of filter media. ACBs can ventilate, pressurize and exhaust air either alone or in combination with air-conditioning systems. Without filter elements or other media to clog, they have no filter media to maintain and they provide constant and predictable airflow, air pressure and electricity consumption.