Fire fighting water nozzle is one of the most important tools to have on hand when responding to a fire. The nozzle allows firefighters to control the volume of water and firefighting foam that is delivered, and it has various spray patterns to support different types of fires. Understanding the options available will help hose operators determine which fire fighting water nozzle is best for their needs.
Nozzles are a critical component of the fire fighting water system and must be designed to support optimal firefighting capabilities. The National Fire Protection Association created guidelines for the construction of fire fighting water nozzles, which define their overall performance and features. Fire nozzles are designed to achieve spray patterns that range from a straight stream to a wide fog. There are also nozzles that are designed to disperse other media, such as an aqueous film-forming foam (AFFF), for specific uses.
The gallons per minute (gpm) that a fire nozzle produces is an essential factor in its ability to reach and penetrate burning materials, cool the fire’s fuel, and extinguish the flames. Most nozzles are manufactured with an expected gallonage at a given nozzle pressure.
In general, the lower the engine pump pressure, the higher the gpm, which is ideal for reaching the seat of the fire, cooling down combustible material and extinguishing flames. However, too much gpm at low pressure can cause an unmanageable flow that limits mobility and endangers firefighters on the line of attack.
To avoid this, nozzle manufacturers design the nozzles to be stable at high nozzle pressure, which reduces their gpm at low pressure. However, achieving this stability often requires sacrificing some of the nozzle’s reach and penetration capability.
Other fire nozzles, such as the constant/select gallonage nozzle, allow firefighters to manually adjust a predetermined discharge rate while the nozzle is flowing. Constant/select nozzles offer several orifice sizes that guarantee a consistent discharge rate.
There are also a number of other fire nozzles that have specific applications, including piercing nozzles, which help firefighters access walls and other hard-to-reach areas, and foam nozzles, which entrain air to create a better solution or foam blanket. All of these nozzles are available in a variety of lengths and diameters to fit the requirements of specific firefighting situations.
Fire nozzles can be loaded onto fire trucks in many different ways, but the most common method is a straight roll. The nozzle is rolled flat, and the male end that connects to the fire hydrant is positioned at one end of the hose. Firefighters then fold the other end over to the male end, creating a compact roll that is easy to transport and deploy in an emergency. This roll also makes it easier to load on a fire truck and less likely to have bumps or creases that could restrict the water flow or cause the nozzle to become blocked. It is recommended that firefighters undergo formal training before using these fire hoses in the field.