Engine 10 was dispatched for a dryer fire. On location, the building, a single-story, mixed use occupancy, was charged with white laminar smoke throughout. The doors were closed. Three people were standing outside the Laundromat and no alarms were sounding. No flames were visible from the exterior. A woman (the 911 caller) directed E10 to the dryer with the fire in it. E10 entered the Laundromat with the thermal imaging camera and a 2.5 gallon water can. Fire was visible through the dryer's glass door. A firefighter opened the dryer door and wet down the towels inside to extinguish the fire. The towels were carried to the exterior of the building and overhauled. A fan was placed to ventilate the building. Ladder 8 checked for extension above the dryer by opening up an area of drywall approximately 8 x 4 inches. Access to the service area behind the dryers was not available immediately because the door was double dead bolted. The business owner was contacted by the Communications Center and told to respond. He opened the service access door. Firefighters inspected the service area behind the dryer and found only light discoloration at the top of the back of the dryer. A fire investigator was called to the scene. A witness at the scene said she was using the dryer, and near the end of the cycle noticed that the dryer was not spinning. When she looked through the dryer door glass, she saw flames. A man in the Laundromat told her to open the dryer door. Her daughter opened the door and the flames got bigger and came out of the dryer. She quickly closed the door and 911 was called.