Fire attack: Advancing hose lines
Here's a look at what the first-arriving crew needs to know about advancing hose line for an interior attack
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 11/2-, 13/4- and 21/2-inch hose lines as primary attack lines. For the purposes of this article, assume these hose lines are preconnected at lengths your department requires and has the type of nozzles you use. Combination nozzles can deliver variable GPM from 65 to 350 based on the hose size. Solid stream nozzles can deliver from 150 to 350 GPM based on hose selection.
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, 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, reduces 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 GPM 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.
- Polyester-jacketed hose 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 and hose size.
Keep these in mind when selecting hose lines that must be stretched over long distances. Smaller diameter hoses such as the 11/2- and 13/4-inch hose should not exceed 300 feet due to friction loss. In addition, 21/2-inch hose lines should not be stretched more than 500 feet for the same reason.
When it's necessary to stretch 11/2- to 21/2-inch hose beyond the above recommended lengths, consider the use of 3-, 4- or 5-inch hose to move water closer to the fire scene, and then dividing the water flow into more manageable attack lines using wyes or manifolds.
Selection the first hose based on 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 a 11/2-inch attack line, the nozzle will flow approximately 30 to 125 GPM. A 13/4-inch preconnect hose and nozzle will flow approximately 95 to 200 GPM. A 21/2-inch preconnected line will flow approximately 125 to 250 GPM.
It is also important to consider these four items.
- How much hose will be needed.
- The location of and access to the fire.
- Staff required to advance the hose to fight the volume of fire based on the initial size-up.
- Staff needed to perform the safe and efficient deployment of the hose 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-foot triple flat load may not be the best selection for a company that needs to consistently remove only a 100 feet for an extrication protection line.
In addition, a 150-foot minuteman load may not be the best preconnect load for a company that consistently stretches a line from a frontage road to a highway for fire suppression or extrication protection. How many curb-line set backs force a 100-foot trash line to be fully deployed to reach that farthest 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. And 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 line to suddenly become charged when the attack crew is still advancing the hose 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. Flow the nozzle long enough for the engineer to set his pump pressure at this time. Being inside is the wrong time to find your nozzle pressure is woefully inadequate because you did not ensure both you and your engineer were on the same page.
Here are five additional points.
- 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 use a short piece of rope or webbing to enable them to close the door quickly if needed.
- 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 it can support the weight of the team. 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 line versus the ability of the team to see the area in front of them.
Feel walls and floors and check the ceiling periodically for fire above, below or beside your crews as they move through the structure. Use thermal imaging cameras to direct interior crews and continue sizing up the structure for fire spread or victim locations.
Continually monitor the line to ensure there is a sufficient amount of hose to reach the fire. This may require some personnel to drop back to assist with moving the line through doors and around corners. Exterior back-up teams can assist with moving the attack line through the front door.
Advance the charged hose into the fire floor and a second charged line (when possible) to the floor above the fire floor. When advancing a line inside a structure and up a stairwell, move slowly up the stairway, continually monitoring the structural strength of the stairs by sounding with a forcible entry tool.
Use a TIC to ensure there is no fire under the stairs. 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, advance the line 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 a 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 a stairwell that is acting as a chimney. Once at the bottom of the stairs, advance the hose line to the seat of the fire.
Next, decide what type of attack to use 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 low.
This attack is delivered through water application directly on the fire with a narrow fog or straight stream, rather than from above it. 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 great when fighting fire in an abandoned building, a building undergoing demolition or that has had previous fires or is under construction. If using 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 using a narrow fog or straight stream in 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. In addition to these lines, consider both sides of the fire for possible extension.
Here are 12 commonsense tips that will assist with safe and efficient hose line advancement, courtesy of the Maryland Fire and Rescue Institute.
- Use solid stream nozzles or set fog nozzles on straight stream setting.
- Stay low upon entering fire area to let heat and gases vent before moving in.
- Before door to fire area opened, all firefighters should be positioned on same side of entrance and remain low.
- Crack nozzle and bleed air out of line ahead of water.
- If fire shows at top of door as opened, ceiling should be hit with solid or straight stream to cool and control fire
- Sweep floor with stream to cool burning debris and hot surfaces.
- Do not open stream until fire can be hit unless firefighter safety involved.
- Direct the stream at the base of fire if localized.
- As the advance is made, the angle of stream should be lowered and an attempt made to hit the main body of fire.
- When the main body of fire knocked down, shut down the stream and let the area vent.
- Upon entering an area which is very hot and finding no fire, withdraw immediately and check the area below.
- When attacking basement fire down interior stairs, use a straight stream because fog will generate steam.
9 additional considerations
- Do not attack the fire from more than on direction to avoid driving heat and fire at the opposing crew.
- Coordinate ventilation with fire attack to reduce fire spread.
- Ventilate just prior to initiating fire attack to reduce the heat level and provide an avenue for steam escape.
- Do not open the nozzle until you are sure of the location of all crew members and other working in the are and that no one is in the doorway.
- Knock down the fire and then move in to extinguish hot spots.
- If you cannot see your feet in the smoke, you should be crawling not standing.
- Always have an escape plan.
- Don't lett the fire cut off your escape route.
- 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.
- Fire Attack