Transitional Attack: When to Use It


To make an argument for using transitional attack as a tactic, it is first important to understand what it is. Textbooks, Internet articles, publications, and fire service leaders give different definitions and opinions for this strategy, but the tactics for this strategy have always been around.

Harold Richman explains it in Engine Company Fireground Operations–Second Edition (1986):

The normal quick interior attack should be made on those buildings which are in use and especially those that are occupied at the time of the fire. However, even in this case, if a large intense fire is encountered, it may be necessary to knock down or control [it] from the outside, if possible, using solid streams, before total interior attack can be made.1

William E. Clark states the following in Firefighting Principles & Practices-Second Edition (1991):

When a fire has extended to the next building before arrival of the first engine company, a complex problem confronts the officer in charge. If personnel are sufficient, lines should be advanced into both buildings simultaneously, but it might be well to use one of those lines to knock down the exterior fire before moving inside. When there are not sufficient personnel to stretch two lines at once, a decision will have to be made as to where to put the first line. It might be well to use it initially between the two buildings in order to extinguish as much fire as possible from one point before moving inside.2

John Norman states the following in Fire Officer’s Handbook of Tactics (1991):

When the officer in command recognizes he may be forced to withdraw from the offensive interior attack, he must immediately begin preparing his defensive positions. This may require calling additional resources, even though pumping capacity and apparatus at the scene are not overtaxed. Sufficient personnel must be available to get the outside streams into position and charged while allowing an orderly withdrawal of interior lines.3

All of these quotes carry the common theme of changing, or transitioning, between the firefighting strategies of offensive, or interior, attack and defensive, or exterior, attack. With this said, Fire Officer Principles and Practices-Second Edition (2010) [International Association of Fire Chiefs (IAFC) and the National Fire Protection Association (NFPA)] provides this definition of transitional attack:

A transitional attack refers to a situation in which an operation is changing or preparing to change. Transitional applies where an offensive attack is initiated, with the recognition that it could be unsuccessful or the situation could deteriorate quickly. The offensive attack is conducted cautiously and in a manner that allows interior attack crews to be withdrawn quickly. At the same time, back-up resources are positioned in defensive positions in case they are needed. This strategy could also be used to quickly conduct a search and rescue operation ahead of a fire, knowing there is only a limited time for crews to get in and out.

A transitional attack could also apply to a situation in which an initial attack is made with an exterior master stream to knock down a large body of fire while crews prepare to conduct an offensive interior attack. The switch to offensive attack should only occur if there are still lives or property to be saved after the heavy streams have been shut down.4

From this definition, it is clear that transitional attack is linked to strategy in the following ways: (1) Transitional attack refers to an interior operation that may be unsuccessful; (2) transitional attack refers to going interior, but only to attempt a rescue, and then getting back out to begin exterior operations; and (3) transitional attack refers to knocking down heavy fire from the exterior with a master stream and then heading inside for an interior attack. How does this apply to an on-scene report when strategy is first selected?

EXAMPLE: Engine 5 on location with heavy fire showing from sides A and B of a two-story, wood-frame. We have a hydrant and will pass command. This will be a transitional attack, and we are going to lead off with a 2½-inch handline.

What is Engine 5 really saying? Would a command officer, or other units, know what Engine 5’s initial action plan is? Engine 5 gave no indication of immediate rescue, so the quick in and out for rescue can be ruled out. Yet, when others arrive on scene and find Engine 5 outside, would they think that Engine 5 is still knocking down the heavy fire and then heading inside or that Engine 5 was inside and was already driven out? What if others arrive on scene and find that the crew from Engine 5 went inside? Would they think this is because they knocked down heavy fire from the exterior and then went in for the kill, or would they think that Engine 5 is inside and is still doubting its success?

The meaning of the term “transitional attack” in an on-scene report can be ambiguous. This on-scene report should be confined to the strategy of an offensive/interior attack because, by definition, a transitional attack is meant to be an offensive/interior attack at some point in the operation. Later-arriving units may be confused relative to the point at which Engine 5 goes interior in this initial action plan. From this communication example, the later-arriving units could interpret the message to mean that the operation started outside and Engine 5 plans to head interior as soon as possible or that Engine 5 is interior and is doubtful about the success of this strategy. To avoid confusion, a better on-scene report would be as follows:

Engine 5 on location with heavy fire showing from sides A and B of a two-story, wood-frame. We have a hydrant and will pass command. This will be a transitional attack after we knock down the fire from the outside with a 2½-inch handline. We will update when we go interior.

Another source of confusion for the fire service is that the term “marginal attack” has been used to mean the same thing as transitional attack. However, marginal attack should refer more to the strategy of a marginal, or doubtful, interior operation or an interior attack for quick rescue and then withdrawal to go defensive.


Let’s look at some of the most recent findings applicable to transitional attack.

In the November 2009 Fire Engineering article “Transitional Fire Attack,” Lawrence Schwartz and Derek Wheeler discussed training and testing done by the Colorado Springs (CO) Fire Department (CSFD). ( They obtained data about the effectiveness of a transitioning attack on second-floor, room-and-contents fires in an acquired structure. From the test fires, after the fire breached the window, a 1¾-inch handline was deployed from the ground using a straight stream into the window and deflecting off the ceiling for five seconds to extinguish the main body of fire. While this was happening, a second 1¾-inch handline was readied and deployed after the first was shut down. The second handline made an interior attack and completely extinguished the fire. The tests showed that this tactic did not negatively disrupt the thermal balance in the room and fire was not pushed into uninvolved areas of the structure as long as the ground-level handline used a straight stream, was deflected off the ceiling, and was shut down when the bulk of the fire was reduced. They called this a transitional attack because the exterior knockdown transitioned to an interior attack.

When comparing the use of the term in this article with the IAFC-NFPA definition, it doesn’t meet any of the three points. It comes close to the third point about knocking down fire from the exterior and then heading interior, but the definition addresses using a master stream to knock down “a large body of fire.” These tests used a 1¾-inch handline, which is not considered a master stream. Also, although this may be open to interpretation, from these tests, fire breaching out of a window may not be considered “a large body of fire.” The authors explain that they use the term transitional attack because the fire is knocked down from the exterior and transitions into an interior attack.

Underwriters Laboratories (UL) and the National Institute of Standards and Technology (NIST) completed research relative to transitional attack. UL conducted experiments in two houses built specifically for testing. In another experiment, UL, NIST, and the Fire Department of New York (FDNY) conducted tests in abandoned two-story townhouses. The tests looked at modern fire conditions and the effectiveness of firefighting tactics in room-and-contents fires. One recommendation from these tests was that water should be applied to the fire as quickly as possible whether from the interior or the exterior. In the UL tests done at the constructed houses, a 1¾-inch combination nozzle was used from an exterior opening (window or door). A straight stream was directed up to and deflected off the ceiling into the fire. The results of these tests and experiments have had a major impact on transitional attack because the tests provided scientific data on a number of relevant points.

  • Water applied from the exterior did not push the fire into other areas.
  • This stream should not block the flow path of fire from the exterior opening.
  • Applying water into the fire area is a fast and an effective way to knock down the fire and improve interior conditions for firefighters and occupant survival. This way, an interior attack based on size-up and safety would follow after the exterior line has been shut down, which would lead to a faster and more effective way to extinguish the fire.

These points give a lot of validity to part of the transitional attack definition provided by the IAFC and the NFPA-specifically, knocking down a large body of fire from the outside using a master stream.

There are two big differences when applying the CSFD and UL-NIST test results to the term transitional attack:

  • Transitional attack calls for a master stream to knock down “a heavy body of fire.” The use of the 1¾-inch handline does not constitute a master stream, and these fires were room-and-contents fires, which may not qualify as “a large body of fire” according to the definition.
  • The term transitional attack does not appear in concluding reports or in the UL online study course. UL refers to applying water as fast as possible into the fire area from the exterior as “softening the target.” Although UL does not call this a transitional attack, some consider this to be a transitional attack and view the results of the UL tests as proof of the effectiveness of a transitional attack.

The definition of transitional attack might be a “work in progress” because it addresses many different points. As a result, the term can be ambiguous and misunderstood. Perhaps there should be different terms for each of the three points in the IAFC-NFPA definition such as the following:

  • Marginal attack could refer to the situation where an interior operation is begun and is unsuccessful or deteriorates so that backup resources are placed in defensive positions. This makes sense because, when used as an adjective, marginal refers to being on the edge of something. In this point, the interior attack is marginal because it could go either way-successful interior or unsuccessful-and you have to withdraw to the exterior.
  • The second point of the definition refers to a quick search-and-rescue attempt ahead of the fire for a limited time. This is a serious situation that must not be confused. To call this transitional attack could be confusing. Maybe it would be better to call this “marginal rescue attack.” Because of fire conditions, you would not go interior unless there was a life to save and, once that rescue is completed, you will probably be exterior and using a defensive operation.
  • Regarding the third point, knocking down heavy fire from the exterior with a master stream and then heading inside for interior operations, our goal should always be safe interior operations when lives or property must be saved. If operations have to start on the exterior to achieve this, as soon as safety allows, we should transition to an interior attack. When this is done, most times the operation should be successful based on size-up and solid operations. There may be times when a 1¾-inch handline may be a better choice to knock down fire from the exterior. What if there is not exactly heavy fire but the fire is significant and spreading upward on the exterior or if the fire building is a one-story ranch private dwelling?

Instead of having one term covering three points, the term should point out the difference between strategies. Therefore, transitional attack should refer to an operation that starts exterior and changes to interior. Then, marginal attack should define interior operations that may change to exterior operations. Finally, marginal rescue attack is a quick in-and-out rescue operation ahead of the fire. Using this interpretation of transitional attack, let’s look at when we should use it.


You arrive on scene as the first-in engine company. Conditions are as shown in photo 1. The size-up indicates that the fire started on the first floor of the left side of the wood-frame building. It broke out of a window on side D and spread to the exposure building on the right. The original fire building is balloon-frame construction and a side-by-side double or multiple dwelling, based on the size and the two sets of stairs off the porch. The exposure building is also of balloon frame and could be a single- or a double-occupancy dwelling. There is little indication as to which it is from the exterior. Since the fire occurred at night time, both buildings will have to be searched quickly. The best thing for the first-in engine company to do is to stop the spread of fire and control it so that search and rescue can be completed. There are at least five fire areas based on the photo:

  • The ground-floor A/B apartment in the original fire building.
  • The ground-floor A/D apartment in the original fire building.
  • The adjacent exterior walls on both fire buildings.
  • The attic of the original fire building.
  • The attic of the exposure building.
(1) Photo by Guy Zampatori Jr.
(1) Photo by Guy Zampatori Jr.

You could make a very strong argument to add the following to this count:

  • The second-floor A/B apartment in the original fire building (from vertical fire spread).
  • The second-floor A/D apartment in the original fire building (also from vertical fire spread).
  • The first-floor of the exposure building (from the exterior windows on side B).
  • The second floor of the exposure building (also from the exterior windows on side B).

As the first-in engine company with other companies a few minutes out, what would be your initial action plan?



  • Use a transitional fire attack. Immediately apply water defensively to stop the spreading exterior fire and knock down the interior fire. This is exactly the key point from the studies and experiments done by UL, NIST, FDNY, and the CSFD: The best thing to do is to apply water as soon as possible-in this scenario, from the exterior. Secure a water supply and lead off with a 2½-inch smooth bore nozzle handline, or deploy a portable monitor to deliver the needed gallons per minute flow for the heavy fire conditions.
  • Place the tip of the handline or monitor between both buildings by the front sidewalk. From the exterior, the water stream will be able to reach most of the areas where the fire is spreading.
  • Direct the first water up into the underside of the soffits for both buildings and down the entire length of the burning area. This will slow the spread of fire into the attics and cause water to cascade down, extinguishing fire on both adjacent exterior walls.
  • You may have to reposition the tip to improve water penetration into the attic space from the soffit. There may be holes or open areas in the soffit that should be exploited to improve water penetration into the burning attic space. Even if there are no holes in the soffit, applying water can still be beneficial, as steam produced from fire extinguishment will slow the fire’s progress in the attic spaces.
  • After the fire along the exterior of the two buildings has been darkened down, direct the water stream into the windows on side B of the exposure building and side D of the original fire building. This will control fire in those areas. Use a straight stream and position it low into the window opening and up to reach deep into the room. The objective is to darken down the fire while allowing steam, smoke, and heat to continue to vent out the upper part of the window. The water stream should not cover the entire window opening; you will lose the benefit of horizontal ventilation. Remove the stream as soon as the fire is knocked down.
  • After these areas are knocked down, direct the water stream into the front openings of the original fire building that are still burning. Follow the same tactic of keeping the stream low into the opening and up to reach deep into the fire area to maintain the ventilation benefits. This should take only a couple of minutes so that additional arriving companies can begin stretching 1¾-inch handlines.
  • Shut the exterior water stream down as soon as possible, and transition to interior operations using the 1¾-inch handlines to extinguish fire after a rapid intervention crew (RIC) has been established.
  • You may have to staff and maintain the exterior water stream as you transition to offensive interior operations.
  • It may take time to get handlines and crews into positions to address all of the fire areas that were previously identified. Deploy handlines and search and rescue crews into fire areas based on situational needs identified by ongoing size-up.
  • Fully extinguish fire areas.
  • Because of the balloon-frame construction, open walls and ceilings to check for hidden fire and spread. During this time, if a fire breaks out and begins spreading in an area not yet covered, you can quickly deploy the exterior line to slow the spread of fire so that interior crews can move in and extinguish fire in that area. This operation can be dangerous and will need to be coordinated with communication to avoid opposing water streams that could endanger the safety of the interior crew.


If the 1¾-inch handline were initially used on the exterior, it would not have had the needed punch, as the master stream would, to knock down the heavy fire conditions and reach the height of the buildings involved. If an immediate interior attack were started using the 1¾-inch handline, to what fire area would you deploy it? This handline cannot be deployed to extinguish fire as fast as the fire is spreading into different areas. Also, do not maintain a defensive attack here. There are too many areas where viable occupants could be trapped and may need immediate rescue. Therefore, a transitional attack from the front of the building is the best option to control fire in different areas. This allows for knockdown of fire from the exterior followed by handlines to the interior to extinguish fire and crews to conduct search and rescue operations.


Photos 2 and 3 show the arrival conditions on sides A and C of a single-family residential house fire.

(2) Side A. (Photos 2 and 3 by Brad Cowan.)
(2) Side A. (Photos 2 and 3 by Brad Cowan.
(3) Side C.
(3) Side C.

On arrival, the fire is spreading quickly into the large, open attic space from an exterior fire on the rear deck. This is a single-family, modern wood-frame building using platform frame construction. Modern wood-frame buildings are similar to balloon-frame construction in one aspect: A fire from a lower level can quickly spread into the attic space. In balloon-frame construction, this happens when a fire spreads to inside a wall void. The wall void runs continuously from the basement to the attic, so the fire races vertically up into the attic space because there is nothing to stop it. In modern wood-frame buildings using platform-frame-construction, this happens when a fire spreads along the outside of an exterior load-bearing wall covered by vinyl siding. The fire burns or melts the siding; the exterior wooden wall easily ignites, and flames race vertically. If the soffit is also covered with vinyl siding, this, once again, burns or melts away, allowing the fire to quickly spread into the attic. This is exactly the problem here.

From the rear, the deck and the exterior wall are involved in fire and are threatening to enter the first and second floors. The fire raced up the rear exterior wall, and flames are showing from the attic. The attic was built to allow air to be drawn in from the soffits and vented out the top ridge vent; now, the fire is doing the same thing. Smoke is showing from the front ridge vent. Since there are no windows in the attic, the attic is not meant to be inhabited and is probably of wood-truss construction.

Since the fire is at night, there may be the need for search and rescue, and occupants may not know the severity of this fire. The engine company needs to quickly control at least three fire areas so that searches can begin and the fire can be extinguished:

  • the exterior deck,
  • the exterior wall on side C, and
  • the attic space.

You could make a very strong argument to add the following to this count:

  • the interior first-floor area adjacent to the burning deck and
  • the interior second-floor area autoexposed from the deck and the burning exterior wall.

    As the first-in engine company with other companies a few minutes out, what is your initial action plan?



    • Use a transitional attack. This scenario is clearly not a total defensive operation. Fire is spreading rapidly, and multiple fire areas need to be addressed immediately. This is very similar to the previous scenario. Although there is not as much fire in this scenario, the attic of this building will be fully involved in just a minute or two because of the modern wood-frame construction and lightweight wood building components used.
    • The engine should follow the same tactics as in the previous situation and immediately apply water defensively to stop the spreading exterior fire and knock down the interior fire.
      -Secure a water supply and lead off with a 2½-inch smooth bore nozzle handline, or deploy a portable monitor.
      -Take the hoseline to side C near the burning open soffit. Direct water up into the underside of the burning open soffit; direct it along the entire length of the burning area. You may have to move the stream along the entire length of the soffit to include parts still covered if the fire has run all along the attic.
      -Use the hydraulic force of the stream to break away the vented vinyl covering the open soffit, and apply water throughout the entire attic as needed. You can also do this on the opposite load-bearing wall on side A. This will slow the spread of fire into the attic and cause water to cascade down, extinguishing fire on the exterior wall. Also, this will slow the spread of fire into the windows on both levels of the house. You may have to reposition to improve water penetration into the attic space from the soffit.
    • As the fire is darkened down in the attic and along the exterior, if fire is venting out of any windows or door openings, direct the water stream into windows and openings following the same procedures previously mentioned. Remember, the object is to quickly darken down the fire while allowing steam, smoke, and heat to continue to vent out the upper part of the opening. Remove the water stream as soon as the fire is knocked down.
    • After these areas are darkened down, direct the water stream onto the exterior deck to completely control the fire. As with the previous scenario, this should take only a few minutes so the additional arriving companies can establish a RIC and begin stretching 1¾-inch handlines that can be deployed when the master stream is shut down for transition to an interior attack.
    • The exterior water stream may need to be staffed and maintained as you transition to offensive, interior operations.
    • It may take time to get 1¾-inch handlines and crews into positions to address all the fire areas previously identified. Crews should deploy to interior operations to extinguish fire and perform search and rescue based on situational needs identified by the ongoing size-up.


    If the 1¾-inch handline were used initially on the exterior, it would not have had the reach and penetration to make its stream reach up and into the large attic space. Also, it would not have had the power to punch through parts of the soffit that were not melted or burned away. The 1¾-inch handline would be the line of choice for an exterior handline if this same scenario was found on a smaller one-story, wood-frame building, but this building is too big and tall. What if the first-in engine company decided instead on an interior attack? Where should the 1¾-inch handline be taken? Should it go to side C on the first level to check for and extinguish interior extension from the exterior deck fire? You may need to knock down the exterior deck fire from here because firefighters should not proceed to the second level if there is a good chance that fire from this area will spread below from this area.

    While this is happening, fire in the attic space is spreading quickly throughout the entire open area. Plenty of oxygen is drawn in from vented soffits and as “seasoned kindling wood” serving the purpose of a wood truss rapidly ignites. Expect a thin line of flames at first to vent out of the top peak; as the fire grows, it will push down into the second floor and sometimes out of the soffits.

    A gable end in the attic will usually fail next with heavy flames venting out, followed by flames burning through the roof deck. Firefighters trying to extinguish the attic fire stand no chance of entering into the attic space because of a small attic scuttle opening and the presence of the web members of the trusses. The fire will be labor intensive and difficult to extinguish. Heat and fire will push down onto firefighters from the attic until a gable end or the roof decking burns away and this heat and fire vent up and out. Also, this is a large attic area with intersecting roofs; therefore, some parts of the attic will not be accessible from a hoseline directed from below up into a single opening at the top of the stairs. Firefighters will have to work on the floor below the attic, pulling the ceiling and applying water from different areas and rooms. This could become a marginal attack and may not be successful.

    The common problem at both of these incidents is that fire is spreading into multiple areas on the interior and the exterior. You must immediately address the exterior spread of fire. An interior handline will not control all the fire areas and exposures as fast as the fire is spreading. An exterior master stream will knock down fire and stop its spread so that interior operations can safely and effectively begin as soon as possible. The exterior application of water for a transitional attack does not spread fire and improves interior conditions. This does not imply that a transitional attack should be used any time fire is venting out of a window or door. If the fire is not threatening a nearby structure or spreading into upper areas, including the attic, the first line should go interior to the fire area.

    There are other factors to consider here as well. First, the side of the building that the fire is showing on could make a difference. Nonload-bearing sides, or gable ends, of the peaked roof buildings do not have soffits, so exterior fire spread into the attic will not be so quick. Also, buildings with peaked roofs have soffits on the load-bearing sides. Older wood-frame buildings and some new ones have soffits that are covered with boards and mostly closed. Fire spread into the attic from an exterior source below is not as quick as it is when soffits are open and covered with vinyl.

    Finally, the finish of the exterior wall can make a difference. A fire with flames well below the soffit overhand may not spread vertically to the attic as fast if the exterior wall has a noncombustible finish like brick. During the initial size-up, the engine company should make a decision about fire attack based on present fire conditions and where that fire is spreading. The first hoseline should attempt to address as many fire areas and exposures as possible.

    Both of these incidents are different. The first incident involves heavy fire conditions in multiple areas, multiple apartments, and two buildings. The second incident is a single-family home, and fire is spreading into different areas of the same building. In both incidents, fire is spreading into different areas faster than the first-in engine company can address the problem. In both of these incidents, understanding and using a transitional attack will be successful. When staffing is low, a 2½-inch handline or a portable monitor leads off to control exterior fire spread and darken down interior fire. Then, as staffing arrives, a RIC is established, 1¾-inch handlines are deployed, and crews go inside so that they can undertake search and rescue and extinguish fire. Transitional attack is very effective and will help you avoid playing catch-up.


    1. Harold Richman. Engine Company Fireground Operations-Second Edition. National Fire Protection Association. 1986, 74.

    2. William E. Clark. Firefighting Principles & Practices-Second Edition. Fire Engineering/PennWell Publishing. 1991, 325.

    3. John Norman. Fire Officer’s Handbook of Tactics. Fire Engineering/PennWell Publishing. 1991, 60.

    4. National Fire Protection Association and International Association of Fire Chiefs, Fire Officer Principles and Practice-Second Edition. 2010, 315.

    SCOTT JOERGER is the captain of Engine 5 in the Rochester (NY) Fire Department, where he has worked for the past 21 years. He is also an assistant chief with the Pittsford Volunteer Fire Department and a former wildland firefighter with the U.S. Forest Service in Oregon. He has an associate degree in fire protection and a bachelor’s degree in management.


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