The primary responsibility for fire control is getting the proper amount of water on the fire in the safest, most efficient manner possible. We constantly drill on how to pull attack lines and we are just as polished at reloading them. But when was the last time you actually spent time considering how to advance lines in an aggressive, intelligent manner?
Currently the fire service has a love for the 1-1/2, 1-3/4 and 2-1/2 inch hose lines as primary attack lines. For the purposes of this article, we will assume that these hose lines will be preconnected and lengths will be based on what your department requires. Combination nozzles can deliver variable gpms from 65 to 350 based on the hose size. Solid stream nozzles can deliver from 150 to 350 gpms based on hose selection. Again, for the purpose of this article, assume nozzle selection of the type utilized by your department.
A consistent argument running through the fire service from coast to coast is the question. "Which nozzle is the best?" I'll not even make an attempt to dive into this one now, but I will list those tasks that are best suited for the tool.
The solid stream and fog steam in a straight stream position does a good job of making safe and effective operations when people are in close proximity to the seat of the fire by reducing steam production, thus aiding rescues. Using narrow or wide fog patterns should be restricted to unoccupied spaces. If the structure is adequately ventilated opposite from the fog nozzle, a fog stream can be used at no more than a 30 degree angle pattern. This, however, does reduce its reach.
When selecting a hose for a primary fire attack, there's a few things to bear in mind:
- The engine company officer and engineer should be aware of the limitations of various sizes of hose such as length, maximum gpms based on hose size and nozzle selection and limitation caused by the hose jacket construction.
- Some departments dictate the use of rubber-jacketed hoses as they are easiest to clean and reload.
- Others swear by cotton-jacketed hoses as they are more maneuverable inside structures while advancing around obstacles. There is also polyester-jacketed hose that has the best of aspects of both the rubber jacketed — which can be cleaned easy and reloaded wet — and the cotton jacketed, which are easily maneuverable around objects.
After considering the flow limitation, consider that friction loss is a significant impact on the effect of fire flow due to internal resistance of water against the hose lining. This flow is impacted by three factors:
- Total flow of water
- Hose length
- Size of the hose selected
Keep these in mind when selecting hose lines that must be stretched over long distances. Smaller diameter hoses such as the 1-1/2 and 1-3/4 hose lines should not exceed 300 ft due to friction loss. In addition, 2-1/2 inch hose lines should not be stretched more than 500 ft for the same reason. When it's necessary to stretch 1-1/2 to 2-1/2 inch hose lines beyond the above recommended lengths, consider the use of 3, 4 or 5 inch hose lines to move water closer to the fire scene, and then dividing the water flow into more manageable attack lines using wyes or manifolds.
The selection of the first hose line will be based upon the total amount of water initially required to extinguish the volume of fire based on the size-up. To do this, we have to understand the volume of water we can obtain from the existing preconnects on our apparatus. When selecting a primary attack lines, we will need to consider what nozzle is on the preconnected attack line. When selecting an attack line of 1-1/2, the nozzle on this hose line will flow approximately 30 to 125 gpms. Selection of an 1-3/4 inch preconnect hoseline and nozzle will flow approximately 95 to 200 gpms. A 2-1/2 preconnected hoseline will flow approximately 125 to 250 gpms.
Other considerations include:
- How far we'll need to stretch the hose line
- Location and access to the fire
- Staffing required to advance the hose line selected to fight the volume of fire based on the initial size-up
- Staffing numbers to perform the safe and efficient deployment of the hose line selected.
Some departments select the style of preconnect hose load from an operations level. It can be more intelligent to allow the company officers in each district to select what they consider to be the best preconnect load based on the impacts of the environments they normally deploy their preconnects in. A 200 ft triple flat load may not be the best selection for a company that needs to consistently remove only a 100 ft for an extrication protection line.
In addition, a 150 ft minuteman load may not be the best preconnect load for a company that consistently stretches a hose line from a frontage road to a highway for fire suppression or an extrication protection line. How many curb-line set backs force a 100 ft trash line to be fully deployed to reach that farthest of dumpsters on fire?
Select the best length and style of preconnect load that works for the majority of calls in the districts you respond in. Just remember to ensure your department SOPs address when to charge a preconnect hoseload. Whether this is an audible, visual or radio-based signal, it is imperative that the engineer knows when to charge the preconnect. It is poor form for the preconnect hose line to suddenly become "charged" when the attack crew is still advancing the hoseline for the best placement.
After the attack line has been selected, deployed and charged, open the nozzle to bleed the air and check the nozzle pattern. It might be a good idea to flow the nozzle long enough for the engineer to set his pump pressure at this time. Once interior, it might be a more difficult time to find your nozzle pressure is woefully inadequate because you did not ensure both you and your engineer are on the same page.
- All personnel on the attack line should be on the same side of the hose.
- Check exterior doors for heat prior to opening. If the door opens inward, stay to the side of it to prevent fire blowing out of the door and exposing the firefighter to dangerous levels of heat or smoke.
- Some departments require their initial attack crews to utilize a short piece of rope or webbing to enable them to close the door if it appears they will need to close the door quickly.
- For doors that open outward, stay behind the door and use it for cover until you are comfortable the environment will allow for keeping it open.
Once the door is open, make a quick sweep of the threshold to quickly look for victims. Prior to entering the structure, sound the floor strongly to ensure the weight of the team can be supported by the existing structure. Stay low when smoke is to the floor, otherwise use your best judgment to gauge the required speed the team is able to advance the hose line versus the ability of the team to visualize the area in front of them for safety.
Feel walls and floors, and check the ceiling periodically to check for fire above, below or beside your crews as they move through the structure. Utilize thermal imaging cameras to direct interior crews and continue sizing up the structure for fire spread or victim locations. Continually monitor the hose line to ensure a sufficient amount of hose to reach the fire. This may require some personnel to drop back to assist with moving the hose line through doors and around corners. Exterior back-up teams may be considered to assist with moving the attack line through the front door.
Advance the charged hose line into the fire floor and a second charged hose line (when possible) to the floor above the fire floor. When advancing a hose line inside a structure and up a stairwell, move slowly up the stairway, continually monitoring the structural strength of the stairs themselves by sounding with a forcible entry tool. Utilize your TIC to ensure there is no fire under the stairs when possible. Lay the attack line along the outside wall to prevent a trip hazard for other teams when possible. Once at the top of the stairs, continue with completion of the hose line advancement to the fire room.
When advancing an attack line down a stairway, move slowly down the stairway making sure to sound the stairs for inherent strength. Monitor any fire that may be under them with your TIC and move feet first down the stairwell. Consider the heat level your team will be advancing through. Monitor for flashover and remember you may actually be advancing down through a stairwell that is acting as a chimney. Once at the bottom of the stairs, continue to advance the hose line to the seat of the fire.
The total number of attack lines may be determined by volume of fire and where lines are required to confine and extinguish the fire.
We have discussed the selection of hose lines, deployment and the manner of attacking specific features that may be contained within a home. By taking these measures, you'll ensure that crew safety is kept in mind based on continual size-up, staying low when necessary and being aware of the impact of stairs on fire behavior.
We can now focus on what type of attack to utilize when reaching the seat of the fire. A direct attack is a good choice when there are smaller fires or when the heat level of the room is at a lower level. This attack is delivered through water application directly on the fire rather than from above it. A narrow fog or straight stream is utilized. This method causes less steam production, which is beneficial to any victims in the surrounding area. An indirect attack — when a fire is attacked from the exterior of the structure — needs to considered very carefully when fighting fire in an occupied structure; steam generation may create untenable conditions for the victims.
This attack is a strong selection when fighting fire in an abandoned building, a building undergoing demolition or that has had previous fires or is under construction. If utilizing this method to fight a larger fire, it may be necessary to knock the fire down or at least control it from the outside using a solid stream — a transitional attack — before making an interior attack.
A combination attack is a good selection when the fire area has high heat levels. This method consists of applying water to the fire and area above it utilizing a narrow fog or straight stream utilizing a T, Z or O pattern. This can also be called "penciling the ceiling," bringing its temperature down to prevent a flashover until the fire can be extinguished.
The total number of attack lines may be determined by volume of fire and where lines are required to confine and extinguish the fire. John Norman's "Fire Officer's Handbook of Tactics" is a great reference on the specifics of stretching hose lines based on the type of structures. But essentially the advancement of hose lines should be a line to the fire, a line above the fire and then a back-up line to the fire. Pretty simple, but it works very well. In addition to these lines, consider both sides of the fire for possible extension.
We have discussed a number of items relating to fire attack and processes, nozzle and hose line selections and procedures in advancing attack lines. With these general categories addressed, here are some commonsense tips that will assist with safe and efficient hose line advancement, courtesy of the Maryland Fire and Rescue Institute:
Tips for efficient hose line advancement:
1. Use solid stream nozzles or set fog nozzles on straight stream setting
2. Stay low upon entering fire area to let heat and gases vent before moving in
3. Before door to fire area opened, all firefighters should be positioned on same side of entrance and remain low
4. Crack nozzle and bleed air out of line ahead of water
5. If fire shows at top of door as opened, ceiling should be hit with solid or straight stream to cool and control fire
6. Sweep floor with stream to cool burning debris and hot surfaces
7. Do not open stream until fire can be hit unless firefighter safety involved
8. Direct the stream at the base of fire if localized
9. As the advance is made, the angle of stream should be lowered and an attempt made to hit the main body of fire
10. When the main body of fire knocked down, shut down the stream and let the area vent
11. When the fire is knocked down, shut down the nozzle
12. Upon entering an area which is very hot and finding no fire, withdraw immediately and check the area below
13. When attacking basement fire down interior stairs, straight stream should be used because fog will generate steam
1. Do not attack the fire from more than on direction to avoid driving heat and fire at the opposing crew
2. Coordinate ventilation with fire attack to reduce fire spread
3. Ventilate just prior to initiating fire attack to reduce the heat level and provide an avenue for steam escape
4. Do not open the nozzle until you are sure of the location of all crew members and other working in the area
and that no one is in the doorway
5. Knock down the fire and then move in to extinguish hot spots
6. If you cannot see your feet in the smoke, you should be crawling and not standing up
7. Always have an escape plan
8. Try to avoid letting fire cut off your escape route
9. Stay with your crew and officer and watch out for each other
Consider the information detailed above with the proper hose selection and remember, when considering hoseline selection rapid fire extinguishment is the best method to keep your crews safe and create a survivable environment for victims. See you next month!