An air purge and pressurization system that utilizes a variable speed fan and a feedback loop to optimize system operation is described herein. In one embodiment, such a system can include an enclosed container located in an area classified as hazardous, a controller rated for operation within the hazardous area, and a pressure sensor located within the container and coupled to the controller. The system can also include a variable-speed fan located outside the hazardous area and coupled to the controller. The controller can be configured to monitor air pressure within the container and variably control a speed of the fan to maintain the detected pressure above a minimum value. Accordingly, a required pressure can be maintained while minimizing a volume of air forced into the container.