Abstract: Infectious diseases may be acquired in public areas such as transportation terminals, shopping centers, schools, hospitals, restaurants and hotels. Large surface areas may be disinfected using a spray system to distribute a suitable fluid such as a disinfectant. Many existing spray systems are large and unwieldy causing operator fatigue. Some spray systems have large, heavy external tanks that provide fluid to the spray system using an external fluid hose. Disclosed is an improved portable spraying system that may be carried by a system operator. The improved system has a tank, a pump, a valve, a nozzle, and a fan all powered by a battery. The tank, the pump, and the battery are arranged to minimize operator fatigue. With the valve set to the priming position, fluid recirculates to prime the pump. Once the pump is primed, the valve is turned to the spray position to begin spraying.