Extraction of vitiated, overheated and contaminated air and the supply and distribution of fresh air in amounts necessary to provide healthful and comfortable conditions for the occupants of the space being ventilated. Applying to offices and workshops means the creation of an environment which stimulates the personnels to higher efficiency. TONSON offers stand, wall mount, axial flow and ceiling air fans for use in harsh environments. Air motors are hermetically protected from dirt and dust. Speed may be adjustable and reversible for ventilation or exhaust. PNEUMATIC AIR FAN & MOTOR FEATURE : 1. NO ELECTRICITY IS NECESSARY. 2. 100%EXPLOSION-PROOF. 3. DESIGNED FOR VARIOUS WORKING ENVIRONMENTS : INFLAMMABLE, CHEMICAL, VOLATILE, HIGH TEMPERATURE, AND HUMID LOCATIONS. 4. DIFFERENT MOUNTING METHODS ARE AVAILABLE. 5. R.P.M. AND DIRECTIONS OF ROTATION CAN BE ADJUSTED EASILY. 6. MOTOR IS HERMETICALLY SEALED TO PREVENT DAIRY AND DIRT.