A delivery device is disclosed that can have a cylinder holding pressurized gas and a cassette holding particles. When the delivery device is actuated, the delivery device can spread the particles over a large target area, with a reasonably uniform distribution over that target area, and can operate quietly. The particles can be held in a cassette. The cassette can be configured to release or discharge over 70% of the particles during use. The device can have a safety interlock to prevent or minimize the risk that the device will be unintentionally activated. The device can have a silencer.