How does a fog nozzle work

Fog nozzles produce a cone-shaped stream of small water droplets. These droplets can more easily be converted into steam, which takes heat from the surrounding air and can even be used to push hot air out of a room. Straight streams discharge water in the shape of a column.

How does an automatic fog nozzle work?

Conventional fog nozzles have a fixed or selectable gpm setting. … With an automatic nozzle, the discharge orifice continually adjusts depending on the flow to the nozzle. This sets the flow being supplied to the proper nozzle pressure and correct velocity for maximum extinguishing capability.

What psi do fog nozzles require at the nozzle?

Most fog nozzles typically operate at a nozzle pressure of 100 psi. Recently, fog nozzles have been produced that operate at lower nozzle pressures such as 75 psi and 50 psi. It is important that if these low-pressure fog nozzles are used that the hoseline is capable of reaching the target flow rate.

What is an advantage of a fog nozzle?

Fog nozzles play an important part in firefighting tactics due to their versatility. The wide variety of fog nozzle manufacturers allows them to accommodate different sizes of fire hose—most often attack hand line—and streams and are capable in both fire protection and attack.

What is the difference between a smooth bore nozzle and a fog nozzle?

Smooth bore nozzles outperform fog nozzles in that they have more operational benefits, which include: greater reach and better penetration. less nozzle reaction except for the 50-psi fog nozzle. less likelihood of being clogged by debris.

At what pressure do you pump a combination nozzle?

Many combination handline nozzles operate at 50 or 75 psi. Manufacturers also make mid- and low-pressure foam equipment.

What is a Minute Man load?

When implementing an aggressive fire attack, advancing hose is an important part of our job. … One such load is the “Minuteman” hose load, which is designed to aid the firefighter in getting the initial attack line in place with ease for any type of operation, be it residential, commercial, or high-rise.

Does fog extinguish fire?

Flames are actually the burning gases liberated by the heated fuels. Water, dirt, foam and retardants will reduce the supply of oxygen for the combustion process. With water, use a fog nozzle. … It smothers the fire by completely coating the fuel with water in the form of foam.

Can fog put out a fire?

High pressure fog machines are made with capacities of from four to sixty gallons of water por minute. course, suction hose equipment, strainers and adapters. coithustion and spread of the fire. action is so rapid that the entire drop of water is converted into steam.

Who invented the fog nozzle?

Fog Nozzle History The first United States patent for a fog nozzle was granted to Dr. John Oyston in 1863. During the late 1800s and continuing through the turn of the century, various articles appeared in fire service literature extolling the merits of spray streams.

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How far can a fire hose shoot water?

How high can a fire hose shoot vertically? Between 75 feet and 100 feet straight up, depending on water pressure. In practice, though, firefighters on the ground rarely attempt to reach higher than 40 feet with hoses.

How fast does water come out of a fire hose?

depends on size of hose and pump pressure. Typical Flows for hand lines – 1 inch hose 30–60 gpm; 1.5 inch hose 125 gpm; 1.75 inch hose 200 gpm; 2.5 inch hose 250–300 gpm. For supply lines depends on the water system, but a 4 inch supply line could be 1000–1500 gpm.

What is a combination fog nozzle?

Combination Fire Nozzle Types The automatic, or constant pressure, nozzle is designed to maintain a relatively constant pressure over a wide range of flows. The multi-purpose nozzle is a combination solid bore and fog nozzle, providing maximum reach and heat absorption.

Which is an advantage of an automatic adjusting fog nozzle?

What is an advantage of an automatic fog nozzle? The flow rate adjusts to maintain the rated nozzle pressure.

What is the nozzle pressure for a master stream with a fog nozzle?

Master Stream Devices: Nozzle Pressure + 10 PSI for the device.

How far is a straight stream of water when hose pressure is 100 psi?

With the flow tests performed, both the low-pressure and standard 100-psi pressure streams were very successful and powerful looking up to at least 50 feet. Many times, evaluation of a fire stream is based on its actual appearance, how clean the stream looks.

What is a Dutchman in the fire service?

Dutchman — A term used for a short fold placed in a hose when loading it into the bed. This fold prevents the coupling from turning in the hose bed.

What is a Cleveland load?

The Cleveland load (aka Metro load or Roundabout load) is handline load primarily used for high-rise applications from what I have found. Other applications would be when deploying a handline not pre-connected to the engine.

What do you flow a master stream at?

A master stream is used when flows surpass 350 gallons per minutes (gpm), becoming too difficult to be delivered from a handline operation because of nozzle reaction. The master stream, which is high in flow and usually a straight stream, is produced with a smooth bore tip or some type of combination nozzle.

How do you calculate nozzle reaction?

The nozzle reaction is found to be: R = ρ Q 2 / A2 , where A2 is the discharge diameter, Q is the volumetric flow rate, R is the magnitude of the nozzle reaction, and r is the water density. This equation shows that the reaction is proportional to the flow rate squared, divided by the nozzle diameter.

What is water mist?

A water mist system is a fire protection system which uses very fine water sprays (i.e. water mist). The small water droplets allow the water mist to control, suppress or extinguish fires by: cooling both the flame and surrounding gases by evaporation.

What is CO2 extinguisher?

CO2 fire extinguishers contain pure carbon dioxide which is a clean extinguishant, leaving no residue. Suitable for class B flammable liquid fires (petrol, oil, solvents), and recommended for use on live electrical equipment.

What is starving of fire?

Starving: limiting fuel by removing potential fuel from the vicinity of the fire, removing the fire from the mass of combustible materials or by dividing the burning material into smaller fires that can be extinguished more easily.

Why do you squeeze the trigger slowly and evenly?

If it is too heavy to hold properly, place on floor next to you and operate. Squeeze the trigger. Squeeze slowly and evenly. This action will release the water and expel it through the discharge nozzle.

How does dirt put out a fire?

But dirt doesn’t cut off the flow of oxygen, it slows it down. That means the coals will last even longer, which is why this is also known as banking the fire, Lundin said, and “if you bank a fire, that makes the hot embers last longer. They think that’s good.

Does cold water put out a fire faster?

It’s a common misconception that spraying cold water on a fire will help put it out faster, but in reality, hot water is more effective in putting out a fire than cold water or water that is at room temperature.

Where did the fog nozzle come from?

Fog Nozzle Origin & Development Prior to and during World War II, the United States Navy and Coast Guard started using a nozzle that was a combination of fog and straight-stream. This all-purpose nozzle had several adapters that made it versatile for many different applications.

Who is Lloyd layman?

Just to refresh everyone’s memory, Lloyd Layman was a Fire Chief that pioneered two fundamental documents in the fire service. The first was called “Attack and Extinguishing Interior Fires”. The second was entitled “Firefighting Tactics and Strategy”. Most of his work was done in the late 1930s and early 1940s.

What is a broken stream nozzle?

The broken or aspirated stream nozzle provides great mobility and excellent gpm flow at low nozzle pressures. … It’s larger than other nozzles and aspirates the stream as it travels through the tip, producing large water droplets to better absorb heat.

Can you drink from a fire hose?

Chances are you’ve heard the adage about drinking from a fire hose but haven’t actually done it. … But the Environmental Protection Agency ruled only recently that the law applies to fire hydrants because they “can be, and are, used in emergency situations to provide drinking water.”

Can a fire hose hurt you?

It stings a bit, even on a narrow fog pattern. But a smooth bore nozzle flowing at 50psi will straight up destroy you. Its literally a solid stream of water. Don’t let the psi numbers fool you.