A portable hand tool includes a housing with a handle configured to be carried by a user and a motor with a motor shaft rotatably extending therefrom. An output shaft rotatably connected to the motor shaft, upon which a cutting blade is rotatably fixed. The cutting blade is substantially enclosed within a blade guard. An impeller is rotatably mounted with one of the motor shaft or the output shaft and substantially enclosed within a fan housing. A plenum is configured to provide enclosed fluid communication between the blade guard and the fan housing, and at least one aperture defined in the blade guard in communication with the plenum.