A Guide to Selecting the Attack Line

Every fire gives clues about which line and tactics you should deploy. It is up to you to recognize these clues, which you can read from the type of construction, how the fire is advancing, smoke conditions, and the occupancy. The selection of the appropriate attack line is crucial to gaining rapid control of a fire; yet, too often, the first-arriving crews pull an undersized attack line, usually the 1¾-inch preconnect, regardless of how large or advanced the fire.

This article focuses on the initial actions of the first-arriving engine company; they are the most crucial actions and set the tone for later-arriving companies and greatly affect the success of the fire department’s operations. Discussed here are incidents at which the fire is readily apparent and immediately accessible because the majority of our fires, especially those involving residences, fit that scenario: We arrive, the flames are visible, and we can immediately get a line in operation and go to work. The objective is that conditions improve once the fire department arrives because the first-arriving engine company rapidly controlled and extinguished the fire.

Command, actions of the second- or later-arriving engine, truck operations, rapid intervention teams, or any other fireground operations are not included in this discussion. Although they are important, there is only so much that the first-arriving engine can accomplish with its staffing and available options. The unit needs to prioritize and maximize its actions; and, in most cases, the most effective action it can take is to get water on the fire immediately after arrival.

The following theoretical fire scenario illustrates that a successful outcome depends on the first-arriving engine’s correctly reading the clues of the fire scene and using the information to plan the fire attack. This theoretical fire occurs in City 1 and also in City 2, and each city’s fire department has its own response plan.

Fire’s General Description

A fire is reported in a single-family residence in a new housing development. Three engines and a ladder company are dispatched. On arrival, Engine 1 with a crew of three, finds a two-story, 2,500-square-foot lightweight construction vinyl-sided house. A well-developed fire in the two-car attached garage is rapidly extending by way of the exterior siding to the second-floor windows and soffit. The house sits 50 feet off the street. A hydrant is directly across from the house, and the second-due company is four minutes out.

City 1. The first-due crew arrives on scene. The engine operator secures a water supply from the hydrant. As the officer conducts the 360° size-up, the nozzleman stretches 200 feet of preconnected 1¾-inch attack line. Once the size-up is completed, the officer and the nozzleman mask up and advance the line in through the front door so they can attack the fire from the unburned side. Fighting their way through smoke and household clutter, they finally make their way to the interior garage door and begin to attack the flames, flowing 125 gallons per minute (gpm) from their fog nozzle. Meanwhile, the fire has extended into the second-floor bedroom and to the attic through the soffit. When the second-due engine arrives, the attic is well-involved.

City 2. The first-due crew arrives on scene. The engine operator secures a water supply from the hydrant. As the officer conducts the engine company size-up, the nozzleman stretches and dresses a 2½-inch attack line with a smooth bore nozzle and immediately begins flowing water onto the exterior siding and into the soffits at 260 gpm. As the extending flames are knocked down and the attic area is cooled, the stream is directed into the garage; rapid steam conversion is achieved. In the meantime, the officer, having completed his size-up, stretches a 1¾-inch line to the garage door and calls for it to be charged and flows 180 gpm through the smooth bore nozzle. When the second-due company arrives, the main body of fire is knocked down. They take the 1¾-inch line into the home to check for extension.

What made the difference in these two scenario outcomes?

City 1. The crew attacked this fire as virtually every other fire it fights–stretch a single 1¾-inch line to the interior. In this case, this action not only delayed water on the fire but also resulted in an inadequate water volume to overcome the British thermal units (BTUs) being produced, and the fire spread to the attic. In short, the crew did not properly size up the fire or read the clues the fire was giving to them (see below). The initial engine crew flowed 125 gpm.

City 2. The crew sized up the conditions and recognized the clues the fire was giving them in terms of fire involvement, rate of fire spread, and building construction. They immediately applied a large volume of water with the 2½-inch line that allowed for reach and penetration into the soffit area, cooling the attic space and overcoming the BTUs being produced by the main body of fire. They were able to rapidly gain control of this fire and prevent it from extending beyond the garage and exterior siding. The initial engine crew flowed 440 gpm.

Engine Company Mission

As you know and as was stated above, the mission of the first-arriving engine company is to get water on the fire as quickly, efficiently, and effectively as possible.

Quickly. Flow water on the fire in less than 60 seconds (depending on obstructions, length of the hoselay, and other factors), or firefighters wearing complete personal protective gear have the line stretched and charged and are ready for entry.

Efficiently. Purposeful movement. Each member knows his job and performs it properly.

Effectively. Rapid cooling and extinguishment. The right flow at the right place at the right time.

It is basic fire science. We need to overwhelm the BTUs the fire is producing using the proper volume of water. When this happens, we gain control of the fire and make conditions safer for those inside and for those about to enter.

Initial Attack Weapons

What are the choices for the initial offensive attack? The most common weapons in your arsenal include the following:

Water Can. A water can may absolutely be used as an attack line. With nothing showing on arrival, someone had better bring the can inside should a fire be discovered after entry. If it’s all you have at the time, it is your initial attack line. Don’t overlook this basic tool and its effectiveness.

1¾-Inch Attack Line. Without a doubt, the 1¾-inch attack line is the most commonly deployed attack line in the American fire service—and for good reason. It can be rapidly deployed and easily advanced with minimal staffing, it is maneuverable inside of structures, and it can effectively flow up to 180 gpm. It can also flow as low as 100 gpm. In the majority of fires we encounter, the 1¾-inch line is the appropriate attack line, but there are times when it is stretched on fire conditions that are beyond, or about to be beyond, its capabilities. Knowing the limitations of this line is vital.

Standpipe Packs. These packs can be made up of two- or 2½-inch hose and a varying amount of hose based on a department’s specific need. They can be time consuming to put into operation. Just because a building has standpipes doesn’t mean you have to use these packs. Depending on the conditions, building layout, and other factors, it may be faster to deploy lines directly off the truck.

2½-inch Attack Line. This line has been the backbone of the American fire service and has been thoroughly misunderstood by many. The line can flow from 250 to 350 gpm. The most common excuses given for not selecting this line are the added weight and the difficulty in maneuvering it. It is not a 1¾-inch line and doesn’t pretend to be. With training and practice, this line can be deployed with minimal staffing to maximum benefit. There is a huge difference between stretching this line and advancing this line. One person can stretch, dress, and flow this line from a stationary position; however, more staffing is needed to effectively advance it into a structure.

Deck Gun. Flowing up to 1,000 gpm or more, the prepiped deck gun is the most underused yet most effective, powerful, and rapidly deployable offensive weapon in our arsenal. Yes, I said “offensive”! We have been conditioned to think of a deck gun only as a defensive weapon. The only time we see pictures or videos of one in use is during “surround-and-drown” operations. This attack line can rapidly knock down a tremendous amount of fire until other companies arrive and handlines can be advanced. It requires a minimum of staffing to place it into operation.

Flow Rates

I won’t spend time on detailed flow rates because there are too many variables to consider. The only way to know what your lines actually flow is to flow test them using your pumps, hose, nozzles, and hose length lays. Then and only then will you know what you are bringing to the fight, which will allow you to make better decisions when selecting lines. Nozzle selection (fog vs. smooth bore) also has a significant impact on flow rates for lines of the same size.

GPS vs. GPM

A newer approach to determining water flow is to use gallons per second (GPS) as opposed to gpm, particularly when flowing larger lines. This formula allows you to see the cumulative effect of the flow every second instead of over one minute. It also helps you to validate going for the larger line over the smaller one without fear of running the tank dry. There are many excellent articles on this subject; I encourage you to read them.

Purpose of the Line

When selecting the initial attack line for a fire, what comes to mind? Is it an automatic reflex to just grab the crosslay; the phrase “big fire, big water”; a standard operating guideline written in stone; or only gpm flow? Selecting the appropriate attack line involves more than just knowing the various flow rates. In fact, flow rates, although important, are not necessarily the primary factor in selecting an attack line. At the end of the day, every attack line will flow only so much water. A 2½-inch will outflow the 1¾-inch, and a deck gun will blow them both away. Before selecting the line, ask, “What is the tactical purpose of the line—what am I trying to do with this line?”

Tactics/Tactical Purpose

Staffing and fire conditions affect the tactics you can employ, and the tactic you choose determines the initial attack line. In the majority of situations, getting water on the fire should be the primary action. Common tactics for the first arriving engine are the following:

Interior Attack. Immediately going interior to attack the fire.

Transitional Attack. Achieving a quick knockdown from the exterior and then rapidly advancing to the interior. This is not a defensive tactic.

Holding Position. Similar to transitional attack; however, conditions or staffing may preclude an immediate advancement into the building, so you are holding its spread until more resources arrive. This also is not a defensive attack.

Defensive. Exterior attack after interior operations have failed or the conditions have been deemed too unsafe to conduct an interior attack.

If we don’t know why we are pulling a particular line (the tactical purpose), it doesn’t matter how much water it flows. We are essentially pulling it for no particular reason. A single 1¾-inch line pulled on a fully involved house fire makes no more sense than operating a deck gun on an oven fire. Neither one has a true purpose for the conditions they were used on, nor was either one the appropriate line. Once we understand the tactical purpose of the line, we can consider the flow rates needed to support that purpose. How do we determine the purpose of an attack line? We first conduct an engine company-based size-up.

Engine Company-Based Size-Up

A proper size-up is crucial to getting an understanding of what you face and developing an overall strategy to manage an incident. But there is a clear difference between conducting a size-up for the first arriving—only—engine on the scene and a size-up for the purpose of command. By narrowing the scope of the size-up, we simplify the thought process for the first-in company officer and allow the officer to put the crew to work where they can accomplish the most good.

UL/NIST Studies

The information coming out of the Underwriters Laboratories (UL)/National Institute of Standards and Technology (NIST) studies is invaluable to determining the attack line and tactics. The research shows that getting water on the fire significantly lowers the temperature throughout the structure, regardless of whether the water came from the interior or the exterior. By cooling the interior, we provide a more tenable environment for civilian occupants, reduce the chance of flashover, and provide a safer environment for firefighters operating within. Using the current science is a vital part of the size-up process to develop the initial tactic. The burning temperature of modern materials is another important factor to consider.

Building Construction

Modern lightweight building construction, especially residential, is built to burn. We have to recognize that fact and respond accordingly. There is a very small window of opportunity for gaining control of fires in these structures. An advanced room-and-contents fire can quickly become a structure fire if we don’t rapidly gain cooling superiority and stop its spread. We need to be able to immediately recognize these “built-to-burn” structures and adapt our tactics to the conditions we encounter.

Fire Advancement/Smoke Conditions

We need to quickly determine if we have a room-and-contents fire, a room-and-contents fire transitioning to a structure fire, or a structure fire. Fires that have progressed into or that are about to progress into a structure fire require a much more powerful attack than those that are still confined to a room.

Reading smoke is a crucial component of the engine company size-up. A fire that has turbulent smoke showing from the structure is very likely going to “light up.” Don’t just look at the flames; look at the smoke volume, velocity, and color to get a sense of what is to come if immediate action isn’t taken.

Staffing/Time

Not every department staffs five members on an engine. The majority of departments in the country run three or fewer, and this will severely impact the tactics you might want to use. If fire conditions are advanced or are rapidly spreading and you have minimum staffing, consider larger attack lines to gain rapid control of the fire. Maximize the power of the staff you have.

Time refers to the length of time it will take you to get the initial line into operation and how fast conditions will change in the meantime.

Weather

Wind is the primary weather factor that affects firefighting. Even small fires in high-wind conditions can rapidly spread beyond the capability of smaller lines. Do not discount the danger of a wind-driven fire.

All of these factors combine to indicate the level of hazards for occupants inside the building. We need to improve their chance of survival by getting the right line in the right place flowing the right volume of water to eliminate the fire threat.

Putting It All Together

After completing the engine company size-up, you can answer the questions “What?” and “How?”

  • What do I have? Room-and-contents/structure fire.
  • How fast is it spreading? Fire advancement, wind, building construction.
  • What can I do about it? Staffing, type of attack.
  • How long will it take me? Time, staffing.

With this information, you can determine the appropriate initial attack line for the conditions you face. It may seem that selecting a line is being made overly complicated. In fact, the opposite is true.

Once the factors that go into line selection are considered, the decision to pull a specific line is done in seconds. Only now, the odds of having pulled the appropriate line have increased because that line was chosen for a specific purpose based on important fireground factors to complete the engine company mission and goals. Let’s take a look.

  • Conditions. Flames and light smoke are visible from one window on the Bravo side of a 1,200-square-foot brick ranch. You have staffing of five. You completed your size-up.
  • What do you have? Room and contents.
  • How fast is it spreading? Slowly.
  • What can I do about it? Get inside and apply water.
  • How long will it take me? Moments.
  • Tactic? Interior attack.
  • Line selection? 1¾-inch.

With these conditions, a crew of five can initiate a rapid interior attack and maintain two-in/two-out requirements, have a backup line in place, or conduct a search.

A three-story, balloon-frame residential home has heavy fire involvement throughout the first floor and around the first-floor wrap-around porch, extending by way of the vinyl siding to the second floor. You arrive with a crew of three.

  • What do I have? Structure fire.
  • How fast is it spreading? Quickly.
  • What can I do? Transitional attack.
  • How long will it take me? Less than 30 seconds.
  • Line selection? Deck gun.

If this fire penetrates the exterior siding into the voids, it will extend quickly into the attic, the home is likely lost, and the survivability of occupants and our ability to reach them are greatly reduced. An immediate offensive attack with a single firefighter operating the deck gun can overwhelm the BTUs being produced by the fire, check its spread, and allow the other members to stretch a line to the structure and secure a water supply. Once the fire is controlled, lines can be advanced into the interior, and search operations can begin.

Every fire we respond to gives clues to help us decide the size of the attack line and the tactics, but are we paying attention to them? The proper size-up of a structure, especially from an engine company perspective, is vital to understanding the severity of the fire conditions.

When faced with a large volume of fire or a rapidly spreading fire, go big on the initial attack, especially with minimum staffing. Each attack line needs to have a tactical purpose for its use.

Companies need to train more on using the deck gun and the 2½-inch attack line as an offensive weapon. We need to understand the difference between “stretching” and “advancing” a line and how many people it takes to do each.

The actions of the first-arriving engine company, from attack line selection to tactics, are the most important actions on the fireground. They lay the foundation for the overall success or failure of the incident.


BRYAN DOWNIE is a 36-year veteran of the fire service and an engine company lieutenant in the Parma (OH) Fire Department. He is a state certified fire instructor.

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