By Paul Shapiro

With water being the primary extinguishing agent for fire suppression, it’s important to be able to deliver the required flow-gallons per minute (gpm)-at the required pressure.

Water delivery systems on the fireground, a.k.a. hose evolutions, have several restrictions that can decrease the flow of the water. Things such as elevation gain or loss, hose friction loss, appliances, plumbing, and nozzle pressures can all impede water flow. Firefighters can overcome pressure restrictions within the specifications of the equipment being used mainly by increasing pump discharge pressure on the engine. Hose evolutions can also be designed to overcome some of the pressure restrictions.

Firefighters need to be well-versed in all equipment and procedures involved with their water delivery deployment. By being well-versed, I mean being educated on all that is involved with moving water for their departments. This is something they can’t accomplish at a fire without having conducted the flow tests properly first.

1 The best way to come up with water flow statistics to be used in designing hose evolutions is to conduct flow tests. Flow tests give you specifics on the gpm and pressure requirements for different evolutions and equipment such as hose nozzles and appliances. (Photos and illustrations by author.)

The best way to come up with water flow statistics to be used in designing hose evolutions is to conduct flow tests. Flow tests give you specifics on the gpm and pressure requirements for different evolutions and equipment such as hose nozzles and appliances. This article is going to talk about specific tests that can be done as well as equipment that is needed and how to properly use it.

My background in teaching water delivery has involved just about every flow test you can think of over the past 30 years. I, like most of you, have learned a lot from the school of hard knocks. I believe it is extremely important to contact flow-testing equipment manufacturers to learn how it is best used.

Pressure Gauge/Pressure Measuring Equipment

Pressure gauges, as they relate to the fire service, have been around for many years. There are two types of pressure gauge instruments that are used for flow testing. One is an inline pressure gauge and the other is a pitot gauge. The inline gauge is considered a wall gauge. In other words, the gauge is inserted into the housing of the inline gauge unit itself from the sidewall. The pitot gauge measures the nozzle pressure of a fire stream, which is than referenced on a chart for the correct gpm. It has a blade with a very small hole on the end that is inserted into the fire stream and sends the pressure to the gauge to come up with a reading. The pitot gauge can either be handheld or set up in a stationary fixture.

The two most common pressure gauges that are used in water delivery flow testing in the fire service are gauges that have two- and five-pound-per-square-inch (psi) increments. The five-psi-increment gauge is the most common one of the two found. Some say that the problem with the five-psi-increment gauge is that you’re guessing what the exact pressure reading is betwe

By Paul Shapiro

With water being the primary extinguishing agent for fire suppression, it’s important to be able to deliver the required flow-gallons per minute (gpm)-at the required pressure.

Water delivery systems on the fireground, a.k.a. hose evolutions, have several restrictions that can decrease the flow of the water. Things such as elevation gain or loss, hose friction loss, appliances, plumbing, and nozzle pressures can all impede water flow. Firefighters can overcome pressure restrictions within the specifications of the equipment being used mainly by increasing pump discharge pressure on the engine. Hose evolutions can also be designed to overcome some of the pressure restrictions.

Firefighters need to be well-versed in all equipment and procedures involved with their water delivery deployment. By being well-versed, I mean being educated on all that is involved with moving water for their departments. This is something they can’t accomplish at a fire without having conducted the flow tests properly first.

1 The best way to come up with water flow statistics to be used in designing hose evolutions is to conduct flow tests. Flow tests give you specifics on the gpm and pressure requirements for different evolutions and equipment such as hose nozzles and appliances. (Photos and illustrations by author.)

The best way to come up with water flow statistics to be used in designing hose evolutions is to conduct flow tests. Flow tests give you specifics on the gpm and pressure requirements for different evolutions and equipment such as hose nozzles and appliances. This article is going to talk about specific tests that can be done as well as equipment that is needed and how to properly use it.

My background in teaching water delivery has involved just about every flow test you can think of over the past 30 years. I, like most of you, have learned a lot from the school of hard knocks. I believe it is extremely important to contact flow-testing equipment manufacturers to learn how it is best used.

Pressure Gauge/Pressure Measuring Equipment

Pressure gauges, as they relate to the fire service, have been around for many years. There are two types of pressure gauge instruments that are used for flow testing. One is an inline pressure gauge and the other is a pitot gauge. The inline gauge is considered a wall gauge. In other words, the gauge is inserted into the housing of the inline gauge unit itself from the sidewall. The pitot gauge measures the nozzle pressure of a fire stream, which is than referenced on a chart for the correct gpm. It has a blade with a very small hole on the end that is inserted into the fire stream and sends the pressure to the gauge to come up with a reading. The pitot gauge can either be handheld or set up in a stationary fixture.

The two most common pressure gauges that are used in water delivery flow testing in the fire service are gauges that have two- and five-pound-per-square-inch (psi) increments. The five-psi-increment gauge is the most common one of the two found. Some say that the problem with the five-psi-increment gauge is that you’re guessing what the exact pressure reading is betwe

By Carl Nix

Flashovers are extremely dangerous and have claimed the lives of too many firefighters over the years.

Many articles and training programs have been produced to help firefighters understand a flashover situation and how to escape safely. In a flashover situation, fire conditions progress rapidly from what was a hot fire to what becomes an inescapable fire.

As an instructor, I have heard firefighters say that a thermal imaging camera (TIC) can help you during a flashover. This is not true. A TIC is a tool to help detect a flashover, but it can’t help you if you’re caught in a flashover. Think about the amount of time, or lack of time, you have in a flashover-two, maybe three, seconds to get out of the situation. You have to move quickly. In this scenario, you don’t have time to look at your TIC.

A preflashover situation is where your TIC can help. Your TIC can give you a visual indication of warning signs that you would otherwise not see. Without your use of a TIC, the thick smoke acts as a visual barrier to what is actually going on above you. Convective velocity, thermal layering, and even rollovers are often hidden inside the smoke and are difficult or impossible to detect. The TIC can help you visualize these events. Your TIC can help you identify how rapidly the fire gases are moving across the ceiling, indicating that they actually have some place to go other than the room you are in. Thermal layering is also visible to the TIC. When one or both of these two visuals change, convective velocity slows or thermal layers descend, it can serve as an early indicator of potential flashover conditions.

1 2 These images taken with a thermal imaging camera show a flashover in progress. (Photos courtesy of Bullard.)

I’ve mentioned this in my previous articles and probably will continue to do so because it’s key to staying safe when entering a burning building: Always have your TIC with you so you can scan a room prior to entry. This is so important when avoiding a flashover. Scanning with your TIC lets you look for signs of excessive heat buildup, particularly near the ceiling, or levels of high heat closer to the floor where you might not otherwise expect them. Your TIC will also help you locate potential vertical or horizontal vent points in case you need them and where the secondary means of egress are. In a flashover situation, these tactics are lifesaving.

Your TIC is there to help you recognize the dangers that you may encounter and how to avoid those dangers so you and your fellow firefighters can go home safely. Simply put, if you have no other means of control such as ventilation or a hose stream, you must get out quickly. If you wait until the flashover is taking place, it’s too late for the TIC to help you escape this extremely dangerous occurrence. A TIC cannot help you in a flashover but it can help alert you to a pending flashover.

1 2 These images taken with a thermal imaging camera show a flashover in progress. (Photos courtesy of Bullard.)

It’s also important to note that the temperature-sensing featu

By Carl Nix

Flashovers are extremely dangerous and have claimed the lives of too many firefighters over the years.

Many articles and training programs have been produced to help firefighters understand a flashover situation and how to escape safely. In a flashover situation, fire conditions progress rapidly from what was a hot fire to what becomes an inescapable fire.

As an instructor, I have heard firefighters say that a thermal imaging camera (TIC) can help you during a flashover. This is not true. A TIC is a tool to help detect a flashover, but it can’t help you if you’re caught in a flashover. Think about the amount of time, or lack of time, you have in a flashover-two, maybe three, seconds to get out of the situation. You have to move quickly. In this scenario, you don’t have time to look at your TIC.

A preflashover situation is where your TIC can help. Your TIC can give you a visual indication of warning signs that you would otherwise not see. Without your use of a TIC, the thick smoke acts as a visual barrier to what is actually going on above you. Convective velocity, thermal layering, and even rollovers are often hidden inside the smoke and are difficult or impossible to detect. The TIC can help you visualize these events. Your TIC can help you identify how rapidly the fire gases are moving across the ceiling, indicating that they actually have some place to go other than the room you are in. Thermal layering is also visible to the TIC. When one or both of these two visuals change, convective velocity slows or thermal layers descend, it can serve as an early indicator of potential flashover conditions.

1 2 These images taken with a thermal imaging camera show a flashover in progress. (Photos courtesy of Bullard.)

I’ve mentioned this in my previous articles and probably will continue to do so because it’s key to staying safe when entering a burning building: Always have your TIC with you so you can scan a room prior to entry. This is so important when avoiding a flashover. Scanning with your TIC lets you look for signs of excessive heat buildup, particularly near the ceiling, or levels of high heat closer to the floor where you might not otherwise expect them. Your TIC will also help you locate potential vertical or horizontal vent points in case you need them and where the secondary means of egress are. In a flashover situation, these tactics are lifesaving.

Your TIC is there to help you recognize the dangers that you may encounter and how to avoid those dangers so you and your fellow firefighters can go home safely. Simply put, if you have no other means of control such as ventilation or a hose stream, you must get out quickly. If you wait until the flashover is taking place, it’s too late for the TIC to help you escape this extremely dangerous occurrence. A TIC cannot help you in a flashover but it can help alert you to a pending flashover.

1 2 These images taken with a thermal imaging camera show a flashover in progress. (Photos courtesy of Bullard.)

It’s also important to note that the temperature-sensing featu

By Carl Nix

Flashovers are extremely dangerous and have claimed the lives of too many firefighters over the years.

Many articles and training programs have been produced to help firefighters understand a flashover situation and how to escape safely. In a flashover situation, fire conditions progress rapidly from what was a hot fire to what becomes an inescapable fire.

As an instructor, I have heard firefighters say that a thermal imaging camera (TIC) can help you during a flashover. This is not true. A TIC is a tool to help detect a flashover, but it can’t help you if you’re caught in a flashover. Think about the amount of time, or lack of time, you have in a flashover-two, maybe three, seconds to get out of the situation. You have to move quickly. In this scenario, you don’t have time to look at your TIC.

A preflashover situation is where your TIC can help. Your TIC can give you a visual indication of warning signs that you would otherwise not see. Without your use of a TIC, the thick smoke acts as a visual barrier to what is actually going on above you. Convective velocity, thermal layering, and even rollovers are often hidden inside the smoke and are difficult or impossible to detect. The TIC can help you visualize these events. Your TIC can help you identify how rapidly the fire gases are moving across the ceiling, indicating that they actually have some place to go other than the room you are in. Thermal layering is also visible to the TIC. When one or both of these two visuals change, convective velocity slows or thermal layers descend, it can serve as an early indicator of potential flashover conditions.

1 2 These images taken with a thermal imaging camera show a flashover in progress. (Photos courtesy of Bullard.)

I’ve mentioned this in my previous articles and probably will continue to do so because it’s key to staying safe when entering a burning building: Always have your TIC with you so you can scan a room prior to entry. This is so important when avoiding a flashover. Scanning with your TIC lets you look for signs of excessive heat buildup, particularly near the ceiling, or levels of high heat closer to the floor where you might not otherwise expect them. Your TIC will also help you locate potential vertical or horizontal vent points in case you need them and where the secondary means of egress are. In a flashover situation, these tactics are lifesaving.

Your TIC is there to help you recognize the dangers that you may encounter and how to avoid those dangers so you and your fellow firefighters can go home safely. Simply put, if you have no other means of control such as ventilation or a hose stream, you must get out quickly. If you wait until the flashover is taking place, it’s too late for the TIC to help you escape this extremely dangerous occurrence. A TIC cannot help you in a flashover but it can help alert you to a pending flashover.

1 2 These images taken with a thermal imaging camera show a flashover in progress. (Photos courtesy of Bullard.)

It’s also important to note that the temperature-sensing featu