RSI Air Makeup Systems, when supplied with the fabric distribution duct, will have a direct impact on employee comfort, morale and productivity. A RSI Air Makeup System can be designed utilizing a variable inlet air damper to effectively control the level of positive pressure in a finishing environment. A more precise method of control utilizes a variable speed AC inverter to precisely control the fan motor speed in response to the pressure sensor placed in the finishing room. As the demand for replacement air increases as a result starting or stopping a spray booth, the air makeup unit responds almost immediately by varying the AMU fan motor speed. This important option prevents an undesirable positive or negative pressure situation from occurring. RSI can also supply combination systems incorporating both 100% supply units in conjunction with variable supply units to satisfy virtually any replacement air requirements.