Nozzle Reaction Simulator Can Improve Fire Attack Skills

CONSIDER THIS SCENARIO: YOU ARE PUSHING THE hoseline down the hallway. Fire shows out of several doorways into the hallway; flames now lick over your head. You move down the hall-one room and then another, knocking down the fire as you advance. Heat keeps you low, down near the floor. The floor is slippery. Finally, you and your partner must rest. The nozzle reaction has simply worn you out.


(1) A spring scale, a couple of loops of webbing, and a solid anchor make a good, practical, and accurate nozzle reaction-measuring system. Our experience with this system indicates that measured nozzle reactions are very close to theoretical values. (Photos by authors.)

Measuring, demonstrating, and evaluating nozzle reaction with quantifiable numbers will help your engine company and your entire fire department to better execute your primary mission, to put out the fire. We have flowmeters, pitot tubes, and theoretical discharge charts to define flows but nothing to measure and demonstrate nozzle reaction in a reliable, repeatable manner, except the actual hoseline flowing water. Attempting to evaluate nozzle reaction under different conditions and varying amounts of fatigue is difficult at best. Ironically, if each rank of the fire service understands, measures, and evaluates nozzle reaction, fire attack operation will improve at every fire.

IDEA’S GENESIS

At the 2005 FDIC, while at dinner after a day of hands-on training, we were discussing how to demonstrate nozzle reaction. Captain Todd Heier’s reply of “Use a spring scale” led to some experimentation and the development of the device that is the topic of this article.


(2) The top handle of the scale provides a solid stop to hold the scale firmly in the pipe. Measure and cut out a window in the pipe so trainees can see the amount of resistance they apply to counter the nozzle reaction.

“Measuring and Demonstrating Nozzle Reaction” (Fire Engineering showed how engine companies can measure nozzle reaction with a spring scale using any nozzle available. Being able to clearly and accurately show firefighters, and possibly decision makers, the actual nozzle reaction (other than the “hold this and feel the reaction” method) will allow them to make better decisions in selecting nozzles, flows, and hoseline size.

SIMULATOR OBJECTIVES

We “reverse engineered” the same principles and tools in the above article to develop a cost-effective and accurate nozzle reaction simulator that can be used for training your firefighters. This measuring device can do the following practical and important functions:

  1. Train recruit firefighters in the proper techniques for the backup position.
  2. Evaluate the skills for the backup and nozzleman positions, different grips, body and leg positions, and hose straps.
  3. Evaluate how to maximize your nozzle team’s effectiveness by measuring how long members can realistically operate with a particular nozzle, flow, and pressure.
  4. Look for ways to reduce fatigue on your attack team members by using hose straps and other tools.
  5. Demonstrate in a realistic fashion the differences in the reactions of nozzles; this information can be used to evaluate fire attack systems.
  6. Demonstrate and evaluate the advantages and disadvantages of various techniques for the nozzleman and backup positions.

CONSTRUCTING THE SIMULATOR

To make the nozzle team training device, start with a portable spring scale, which you can purchase at any outdoor supply store. Select a scale that reads from zero to at least 150 pounds. Next, take a four- to six-foot piece of schedule 40 PVC pipe. Choose a diameter that will allow your scale to slip inside it; we used a two-inch-diameter PVC pipe. Lay out, measure, and cut out a small window in the pipe so the operator can read the numerals of the scale inside the pipe. Tie a piece of webbing or rope to the hook on the scale and thread it through the pipe. Attach the webbing to a substantial object. Apply forward pressure to the system, and begin the training session.


(3) Wrapping some hockey tape around the pipe gives it the feel and texture of a jacketed hoseline.

You can use this device to train the nozzle firefighters to find their most comfortable position. It can also be used to help inexperienced backup firefighters get a feel for how much effort is needed for this important position.

HOW TO USE THE SIMULATOR

Secure the webbing to an anchor point on or near floor level. One option around the firehouse is to secure it to a halligan tool and pass the webbing under an inward opening door. An alternative is to run a piece of webbing or rope around one of the tires on the rig and use that as an anchor (photo 4).


(4) Run a piece of webbing or rope around one tire of a rig to anchor the simulator.

Debates rage in firehouses across our nation about which nozzle is best. To choose a nozzle system that is right for your department, you must evaluate its flow, reach, penetration, and reaction; you must also determine how well the nozzle operates over a variety of operating pressures.


(5) A firefighter practices his nozzle and backup position skills with the scale visible (turned in this picture for the camera) so he can gauge the amount of force he must apply to counter the nozzle reaction.

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(6) The firefighter practices an alternate leg position while maintaining a view of the scale to ensure that he counters the nozzle reaction. Much has been written about the appropriate amount of upper body strength needed to be a good nozzle or backup firefighter. This device provides a way to measure that value.

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(7) With the scale visible, the firefighter can judge the amount of force he must exert to counter the nozzle reaction.

This device clearly shows the nozzle reaction for any flow and pressure combination in a consistent and repeatable manner. It is another tool for improving engine company operations.

Endnote

1. “Measuring and Demonstrating Nozzle Reaction,” Christopher Flatley, Tim Pillsworth, and Jerry Knapp, Fire Engineering, April 2006.

JERRY KNAPP is a training officer at the Rockland County Fire Training Center in Pomona, New York. He is a 33-year veteran firefighter/EMT with the West Haverstraw (NY) Fire Department; a battalion chief with the Rockland County Haz Mat Response Team; and the plans officer for the Directorate of Emergency Services at the United States Military Academy at West Point, New York. He has a degree in fire science and is an FDIC HOT Engine Company instructor and seminar presenter.

CHRISTOPHER FLATLEY, an 18-year veteran of the Fire Department of New York, is a lieutenant assigned to Ladder 21 in Manhattan. He is a nationally certified fire instructor I and an instructor at the Rockland County Fire Training Center in Pomona, New York. He has been a presenter at FDIC.

TODD HEIER, a 17-year firefighter/EMT, is the captain of education and safety for the Fishers (IN) Fire Department. He is also a member of the Hamilton County Haz Mat Team, the Fishers Technical Rescue Team, and the Indiana District 5 Training Council. He has a degree in public safety technology.

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