The 4 Phases Of the Stretch: Phase 4

The moment of truth has arrived. You are kneeling outside the attack entrance. Boiling, black and gray smoke pushes from the top of the door. Your hoseline stretch is complete you and your partner are donning the rest of your personal protective equipment (PPE). It’s time to push in and extinguish the fire.

For those called to be firefighters, there is no greater job than having the nozzle at a fire. There is no greater praise than the words “nice job” after extinguish a fire. But don’t forget what got you to this moment – preparation and training, conducting a good size-up and stretch estimate, knowing your job and making an efficient stretch.

The basics of suppression

Before we get into the particulars of how to make our advance, we must make sure we have a thorough understanding of the tools, techniques and theory of how to safely and efficiently extinguish a fire. We are taught in basic training that water extinguishes fire by absorbing heat, butut in order to be effective, water must be applied at a rate faster than the rate of heat being generated. The goal is to cool the involved combustibles, dropping them below the temperature at which they produce ignitable vapors and heat to support the fire’s growth. According to the National Fire Protection Association (NFPA), the application rate and type of stream are the key factors that ultimately determine the speed of extinguishment.

• Application rate – When we talk about application rate, we are talking about how many gallons of water a particular size hoseline and nozzle combination can flow per minute (gpm). NFPA 1710, Standard for the Organization and Deployment of Fire Suppression Operations, Emergency Medical Operations, and Special Operations to the Public by Career Fire Departments, 2010 edition, establishes a flow rate of 300 gpm from the first two handlines, each of which should flow a minimum of 100 gpm. Other research and testing has established a minimum of 150 to 180 gpm from any single hoseline as the flow rate for fire attack in today’s modern fire environment. Simply put, as the heat-release rate of modern combustibles increases, so must the application rate of water to extinguish the fire.

• Type of stream – When selecting the appropriate nozzle and stream, firefighters must understand the differences between them. The purpose of this article is not to recommend a particular type of stream or nozzle, but rather to make sure you are well-versed about the nozzles carried on your engines. Are you aware of their flow range, stream type and pattern capabilities? Do you realize that all nozzles are not created equal and that each possesses characteristics that will affect your extinguishment effort?

Nozzles & streams

A combination fog nozzle produces a broken water stream. The stream is broken apart as it makes contact with the baffle, or disc, inside the nozzle creating small fine water droplets as it leaves the nozzle. The water droplets have more exposed surface area to allow for maximum heat absorption. It is capable of providing a wide to narrow fog stream and a compact straight stream as well.

The stream produced by a smooth-bore nozzle is a continuous bore of water that flows unimpeded through the control handle, or “bale,” and out the tip. It creates large, coarse water droplets when deflected off of a solid surface such as a wall, ceiling or floor. The water passing through the nozzle moves at a higher velocity, allowing for maximum reach and thermal penetration.

Combination fog nozzles come in different types and configurations – do you know what type is carried on your engine? Do you understand its basic design and are you aware of all of its moving parts and what they do? How do you shut the flow on and off? Which way do you turn the bezel to go from fog to straight stream? How do you adjust the gpm setting? Does one part perform multiple operations? You must know this information well before the advance!

Nozzle reaction forces

Do you understand what nozzle reaction forces are and how they impact our ability to extinguish a fire? Nozzle reaction is created by the volume of water leaving the nozzle and the pressure at which that water leaves the nozzle. Captain Dave Fornell and Firefighter Paul Grimmwood have conducted extensive research revealing that firefighters struggling to manage nozzle reaction forces are not able to focus on safely fighting the fire.

1. What is your department’s minimum tactical fire-flow requirement?

2. Are you really achieving the fire flow you think you are?

3. Are your nozzle reaction forces within your crews working limits?

4. Is your current hose and nozzle configuration effective and safe for the modern fireground?

The only way to establish the effectiveness of your hose and nozzle configuration is to conduct a formalized evaluation to ensure your firefighters are going to battle with the most efficient and effective weapon. Many departments conduct this type of testing after a close call or line-of-duty death. Don’t wait until a tragedy forces you to react to your departments limitations, make the effort to ensure you are giving your firefighters there best chance of safely extinguishing the fire.

Proper stream application

How you position your body and the manner in which you make your advance are crucial to the success of the advance. You and your partner should be on the same side of the line, and down low. One popular method is crawling on both knees. This method is helpful during high-heat conditions so you can stay low.

The leg-forward method lets you use your outstretched leg to feel debris, holes or stairways in front of you before the full weight of your body comes in contact with the obstacle. The nozzle firefighter should hold the line at arm’s length out in front for maximum maneuverability. If you let the nozzle to push back close to your body, it will be impossible to maneuver properly.

While advancing, your stream should be operated forward and upward in a rapid side-to-side or clockwise rotation striking the ceiling and the walls. This is done so your stream can break up and cool superheated ceiling gases and cool the primary radiant heat sources. Don’t forget to sweep the floor to cool burning material ahead of your advance to prevent knee burns. As the fire darkens, the stream should be lowered to cool the primary fuel source.

The officer’s role during the advance

After taking command of the stretch, the officer should try to locate the fire while the crew is making the stretch. Depending on the type of structures you respond to and the location of the fire within it, you may be able to do this from the exterior while conducting your 360-degree size-up. But there may be times when you have to enter the structure ahead of the nozzle team to determine the quickest and most direct route to the fire. The decision to enter ahead of the attack line should be not be made arbitrarily, but should be based on the current fire and smoke conditions and your ability to do so safely. The officer-in-charge should don all PPE, including self-contained breathing apparatus (SCBA), a portable radio and a thermal imaging camera. Determining the route ahead of the attack line’s advance can have a major impact on your crew’s ability to quickly and safely extinguish the fire.

Once the stretch is complete and the location of the fire has been determined, you must take command of the hoseline advance. Many departments have policies dictating that the first-in engine officer should remain outside of the structure to take command and initiate the Incident Management System (IMS). Since the actions and decisions of the first-due engine and the primary attack line will have a major impact on the outcome of the fire, the first-in engine company officer must have the flexibility to go with the crew when the fire conditions and the crew’s experience level dictate the need for close crew supervision.

Before advancing through the door, the officer must ensure that the crew has donned all PPE and should relay the information gathered during their size-up such as the fire’s location and intensity, location of the stairs or how far inside the entrance the fire is located. As soon as entry is made into the fire the officer must evaluate conditions and make any adjustments necessary to the advance. The officer’s presence lets the nozzle team focus on nozzle operation and hose advancement, since the officer is constantly monitoring the fire and smoke conditions for any changes and can quickly notify the crew.

Because it is almost impossible for the nozzle team to monitor radio communications due to the noise created by the stream extinguishing the fire, the officer can monitor radio communications for critical information. The officer should maintain a position slightly higher than the nozzle team and directly behind the nozzle firefighter to communicate orders and directions.

Conclusion

The only way for an engine company officer to be fully aware and accountable for the crew’s well-being and actions is to be with them during high-risk operations. The only way to ensure that the fire has been located confined and extinguished is to have direct supervision over the operation. A leader’s job is to inspire his or her personnel through actions, not just words.

Congratulations – you have mastered the art of the stretch, quickly extinguishing the fire and making the fireground safer.

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