Andrew Fredericks

Advancing the First Handline

Part 3

This installment will discuss proper nozzle technique (also called “nozzle mechanics”) and burn-injury prevention during fire attack.

The two most frequent mistakes I observe when training firefighters in proper nozzle mechanics are these: 1.) Failure to open the nozzle fully for maximum flow and stream reach and 2.) Being too timid when manipulating the nozzle. Previous installments have discussed why only straight or solid streams should be used for interior attack. It is vital that these streams have adequate volume, reach, and penetrating power in order to achieve rapid fire control and keep the nozzle team safe. While straight and solid streams provide many benefits for the fire attack team, the compactness of these streams requires vigorous nozzle movement in order to distribute the water efficiently over the heated fuel materials.

The first mistake, partially closing the nozzle shut off (often done in order to manage excessive nozzle reaction) will produce several negative consequences depending upon the specific type of nozzle involved. In the case of solid-stream nozzles, partially closing the shut-off not only reduces flow volume; the intrusion of the ball valve into the waterway creates significant turbulence that has a negative effect on both the reach and quality of the stream. With a combination (fog) nozzle, both flow volume and effective reach will be compromised. Automatic fog nozzles can be rather deceiving. While stream characteristics (reach, compactness) are maintained and the stream may “look good,” the consequent reduction in flow volume will lessen fire-control effectiveness.

Being overly timid when manipulating the nozzle is another common mistake. Fires are controlled quickly when an adequate volume of water is efficiently applied on the heated fuel materials. If the nozzle firefighter fails to move the nozzle in a vigorous, almost violent fashion, fire control is delayed and the risk of burn injury is increased. It seems there are two main causes for this problem. One is simply a lack of experience and/or poor training. The other is the widespread use of pistol grips. Pistol grips, particularly when installed on 100-psi fog nozzles with their high reaction forces, tend to end up alongside the nozzle firefighter's body. The arm holding the pistol grip is bent at a 90-degree angle and nozzle movement is severely restricted.

While rapid nozzle movement is important, the pattern of these movements must also be discussed. Most of us have heard at one time or another that the nozzle should be rotated with a clockwise motion. If the nozzle were to be rotated counterclockwise, heat, smoke, and flame would be drawn to the nozzle and increase the threat of burn injury. Although this phenomenon has been demonstrated repeatedly and is a proven scientific fact, it applies to fog streams, not straight or solid streams. (It should be noted that the reason for this phenomenon has been debated for many years and explanations have ranged from the effects of charged ions in the atmosphere to the Coriolis force caused by the rotation of the earth.)

In my own experience, the exact pattern of movements will depend on both the size and shape of the fire area and how close I can get to the fire before opening the nozzle. While I generally use a clockwise rotation, side-to-side movements and even up-and-down movements may also be incorporated into the mix. If one combination of movements isn't having much effect, try another. If this still proves less than satisfactory, you may need to seek another vantage point for stream application.

The nozzle should initially be pointed toward the ceiling of the fire area in order to agitate the fire gas layers and break up the stream. This creates coarse droplets that will rain down on the heated contents, efficiently knocking down the fire by eliminating the release of fuel vapors into the atmosphere. Be careful not to let the stream contact the heated ceiling and walls in your immediate vicinity, as this will cause scalding water to splatter about, increasing the burn-injury potential. As the fire “darkens down,” the nozzle angle should be reduced and the stream aimed into the lower portion of the fire area.

Once the fire is controlled sufficiently to permit the forward advance of the line, the floor must be swept with the stream. Sweeping the floor accomplishes several important safety objectives. It pushes aside sharp objects from the nozzle team's path. These may include nails, screws, glass, and hypodermic needles. It extinguishes burning carpeting and cools molten floor tiles and plastics. Sweeping with the stream also “sounds” the floor. A change in the sound of the stream will indicate the presence of an opening ahead. This opening may be the entrance to the cellar stairs, an unprotected shaft, or even a hole in the floor caused by fire burning through from below.

A new burn prevention poster sponsored jointly by the New York City Fire Department (FDNY) Safety Command and the New York Firefighters Burn Center Foundation encourages the nozzle team to “sweep-switch-squat-shift” when advancing the line.* Sweeping with the stream dilutes and cools the runoff water cascading down the walls and collecting on the floor. This runoff water will be scalding hot — as high as 150 degrees Fahrenheit. Water this hot will cause a third-degree burn after only one second of contact with human skin. Even bunker pants will not protect against scald burns.

Switching knees will reduce the contact time between the heated floor and your anterior shin and knee. Consider that when you kneel, your bunker pants are stretched tight over the knee joint, eliminating the air space between the protective layers and increasing the risk of conductive heat burns. Squatting or “duck” walking is also effective, but it is rather difficult for the average firefighter to maintain this posture for an extended period.

Until next time, stay safe.

*The poster is available for a small donation by contacting the New York Firefighters Burn Center Foundation at their website: www.NYFFBurnCenter.org.

Andrew Fredericks is the author of three "Bread and Butter" Operations videos titled Methods of Structure Fire Attack, Stretching the Initial Attack Handline and Advancing the Initial Attack Handline. To purchase, click here.

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