Da Clamp

As the weather improves, it's an ideal opportunity to engage in outdoor training exercises. This month, we'll delve into a nozzle technique known as the Clamp. Made famous by Aaron Fields (Seattle FD) and his training company: Nozzle Forward, this method is tailored for the 3-firefighter engine crew, empowering the nozzleman to handle the 1 ¾ or 2 ½ handline without immediate help from another firefighter.

Before jumping into the technique, it's essential to understand the significance of good nozzle technique. Let's revisit Newton's Third Law from middle school science class: for every action, there's an equal and opposite reaction. Applied to a flowing nozzle, this means that as water exits the nozzle, a force, known as nozzle reaction, is exerted back on the firefighter. Nozzle reaction varies based on the gallons per minute (GPM) flowing from the nozzle. For instance, a 1 ¾” handline pumped at 50 psi through a ⅞” smooth bore nozzle will flow 160 GPM, resulting in 54 pounds of force (lbf). Similarly, a 2 ½” handline pumped at 50 psi through a 1 ⅛” smoothbore nozzle will flow 266 GPM, resulting in 99 lbf.

Paul Grimwood’s (ret. London Fire Brigade) work has established general guidelines for how much nozzle reaction a firefighter can safely and effectively handle - 1 firefighter can handle up to 60 lbf, while two firefighters can manage up to 75 lbf, and 3 firefighters are necessary for 95 lbf. For further details, refer to Grimwood's article "Firefighter Nozzle Reaction" available under the Resources tab.

As the nozzle firefighter works to combat the force created by the nozzle reaction, the old adage "work smarter, not harder" applies. By employing tried and true techniques that diverts the nozzle reaction, as opposed to muscling the hoseline resulting in them becoming fatigued quickly. When the nozzle firefighter becomes fatigued due to battling nozzle reaction, they will have a tendency to close the bale, resulting in no water being flowed. Therefore, using proper technique is not only easier on the firefighter, it is also safer as it facilitates an open bale.

Now that we understand the rationale behind proper nozzle technique, let's explore the Clamp technique. As depicted in the image, the Clamp position mirrors the Tripod position discussed in last month’s search article, only now we are adding a hoseline. The key to the Clamp position lies in using the ankle/shin bone to anchor the line to the ground. By leaning back on their heel, firefighters can leverage their body weight to secure the hoseline in place. There should be sufficient line in front of the firefighter to allow the nozzle tip to extend just above the brim of their helmet. This will allow for water application in any direction. 

Here are a couple of additional pointers:

• Notice the bale is turned toward the firefighter’s body. This facilitates easy opening and closing of the bale with the firefighter’s left hand, when their right knee is down (or vice versa).

• Positioning the right hand roughly ¾ of the way between the nozzle and the ground provides support to the hose and prevents hose bending.