The department uses a limited set of standardized hand signals to communicate in environments where voice communication isn't possible. Some situations that could require non-verbal communications are lack of a hand-held radio, excessive distance between the two firefighters, high levels of background noise, excessive radio traffic, or wearing an SCBA respirator or hazmat suit.
These signals are used by both the engineer at the engine and the firefighter at the hydrant to indicate when to start or stop the water flow, to acknowledge the message, and to confirm that they have complied.
These signals are used to guide apparatus when backing up. Apparatus must always have someone behind the rig to guide it when it is backing up, due to the size of the vehicle and lack of rear visibility.
These signals are used to guide a helicopter safely down onto it's LZ, or landing zone. Medevac helicopters are often called upon to transport victims when time is critical, and they often have to land on roadways, fields, or parking lots. Since there are often power lines, trees, and street lights nearby, an LZ is selected that will allow the helicopter to land as safely as possible. Since helicopters make lots of noise, and operate on different radio frequencies than those used by firefighters, these signals are used by the person on the ground to guide the helicopter during landing and dustoff.