An elbow nozzle/fire nozzle/water cannon  often used in firefighting and industrial applications, is a type of nozzle that incorporates an elbow or bend in its design. This design feature enables the nozzle to direct a fluid, often water or a fire retardant, at angles divergent from the line of the hose or pipe to which it is attached. This ability to spray at different angles makes it especially useful in situations where direct access to the fire or target area is obstructed or limited. 

 

In firefighting, an elbow nozzle can be particularly valuable in urban environments or cluttered spaces where fires may start in hard-to-reach locations, such as behind machinery or in attic spaces. The angled design allows firefighters to more effectively aim and apply the extinguishing agent to the base of the fire from a safer position or a better angle, contributing significantly to firefighting efforts and safety.