MONITOR NOZZLES

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Part Identification

Nozzle Operation

1. Nozzle Coupling
   The Master Foam nozzle is available with 2½"(161mm) female threads (NH, NPSH or BSP). When tightening the coupling, make sure the foam inlet is pointing downward for ease of attaching the concentrate inlet hose.
   
   CAUTION: Nozzle threads must be mated correctly. Mismatched or damaged threads may cause nozzle to leak or uncouple under pressure and could cause injury.
   CAUTION: Do not couple aluminum to brass. Dissimilar metals coupled together can cause galvanic corrosion that can result in inability to unscrew the threads or complete loss of thread engagement.
   


2. Flow Characteristics
   Figure 1 gives the flow characteristics of the Master Foam nozzle. Pressure on the graph is the nozzle inlet pressure. Losses through piping and monitor must be taken into account to deliver the desired pressure to the nozzle. Flow on the graph is the water flow entering the nozzle. Any foam educted will add to this flow.

   WARNING: An inadequate supply of nozzle pressure and/or flow will cause an ineffective stream and can result in injury, death or loss of property.

   Figure 1: Master Foam Flows

   

3. Pattern Control
   The Master Foam's spray pattern is adjustable from straight stream to a 90 degree wide fog. Turning the stream shaper clockwise (as seen from the operating position behind the nozzle - see figure 2) moves the shaper to the straight stream position. Turning the shaper counterclockwise will result in an increasingly wider pattern. Only 90 degrees of rotation is required to go from wide fog to straight stream.

   Since the stream trim point varies with flow, the stream should be "trimmed" after establishing a steady flow. To properly trim the stream, first open to a narrow fog. Then close the stream to parallel to give maximum reach. NOTE: Turning the shaper further forward will cause stream crossover and reduce the reach of the nozzle.

Figure 2: Pattern Control and Flushing



4. Flushing Debris
   Small debris in the water may get caught inside the nozzle. This trapped material will cause poor stream quality, shortened reach and reduced flow. To remove debris trapped in the nozzle:
   • Shut off flow to the nozzle.
   • Unscrew baffle (see figure 2) using 1 1/8" (28mm) socket.
   • Remove debris. Flow water to flush if necessary.
   • Reinstall baffle. Tighten to approximately 30 ft.-lbs. (40 Newton-Metres).

   WARNING: Large amounts of debris may be unflushable and can reduce the flow of the nozzle resulting in an ineffective flow. In the event of a blockage, it may be necessary to retreat to a safe area.

   Larger debris can get caught in the nozzle ahead of the cast vane. If this occurs uncouple the nozzle to clear the blockage.




5. Use of Foam
   Refer to fire service training for the proper use of foam.

   WARNING: For Class B fires, lack of foam or interruption in the foam stream can cause a break in the foam blanket and greatly increase the risk of injury or death. Make sure that:

   • Application rate is sufficient (see NFPA 11 or foam manufacturer's recommendations).
   • Enough concentrate is on hand to complete the task (see NFPA for minimum duration time requirements).
   • Foam logistics have been carefully planned. Allow for such things as:
     • Storage of foam in a location not exposed to the hazard it protects.
     • Personnel, equipment and technique to deliver adequate foam.
     • Removal of empty foam containers.
     • Keeping clear path to deliver foam as hoses, other equipment and vehicles are deployed.

   WARNING: Improper use of foam can result in injury or damage to the environment. Follow foam manufacturer's instructions and fire service training to avoid:

   • Using wrong type of foam on a fire, i.e. Class A foam on a Class B fire.
   • Mishandling of concentrates, some of which are flammable.
   • Plunging foam into pools of burning liquid fuels.
   • Causing environmental damage.
   • Directing stream at personnel.

   WARNING: there are a wide variety of foam concentrates. Each user is responsible for verifying that any foam concentrate chosen is suitable for the purpose intended.

   
   

6. Foam Selection
   See Figure 4 for a summary of typical uses for various foam types.

   Figure 4-Basic Guide to Foam Selection and Use
   

7. Foam Selection
   See Figure 5 for a summary of typical uses for various foam types.

   Figure 5-Basic Guide to Foam Selection and Use
   
   
   

8. Setting Foam Percentage
   The foam percentage is controlled by an orifice plate that is installed in the nozzle at the mouth of the concentrate inlet (see figure 6). The Master Foam comes with orifice plates for 0.5%, 1%, 3% and 6%. Each orifice plate is marked with the percentage and nozzle flow rate. The flow rate on the orifice plate must match the flow rate marked on the nozzle's baffle. The chart in figure 6 gives the nominal rates of foam usage. Accuracy of proportioning is fairly insensitive to nozzle inlet pressure. The graph in figure 7 gives expected percentages for various inlet pressures.

   To install the orifice plate in the nozzle simply push it into the bore at the concentrate inlet on the nozzle. The orifice plate has an O-ring to hold it in place.

   To remove the orifice plate, hook a small object (such as a screwdriver or Allen wrench) into the hole in the orifice plate and pull it out. Take care not to damage the orifice. Note: The hole in the 6% orifice plate is big enough that your finger can be used to pull it out instead of a tool.

   Figure 6-Concentrate Usage Chart
   

   Water Flow (GPM)	Foam percentage
   	0.5%	1%	3%	6%
   350	1.8	3.5	10.8	22.3
   500	2.5	5.1	15.5	31.9
   750	3.8	7.6	23.2	47.9

   Example: 500 gpm of water at 3% uses 15.5 gpm of concentrate
   NOTE: Flows shown are minimal. Actual results may vary based on brand and condition of foam.

   Figure 7-Proportioning Accuracy with Pressure Variation
   

   NOTE: In any eductor type system the accuracy of proportioning depends on the viscosity of the foam concentrate. The orifice plates for the Master Foam nozzle have been calibrated at 70 degrees F as follows:

   Percent	Foam Used for Calibration
   0.5% & 1%	Class A foam of 20 centipoise viscosity
   3%	3M ATC 3 AR-AFFF product code ATC-603
   6%	3M ATC-AFFF product code FC-600F

9. Concentrate Hose Connection
   The concentrate hose is attached to the Master Foam nozzle by a 1.5"(38mm) cam lock fitting (Military Standard: MS 27019). Orient levers to avoid interference with the stream shaper and push the fitting onto the concentrate inlet on the nozzle. Fold both levers until they touch the hose to lock. The other end of the hose is fed into a foam container. An optional hose is available with female camlock fittings on each end. Hose connection and typical set ups are shown in figure 8.

   Figure 8-Typical Master Foam Set Ups

   

10. Use of FoamjetLX
    To increase the expansion ratio, Task Force Tips' "Foamjet LX" (Model FJ-LX-M) may be used. This low expansion foam tube attaches and removes quickly from the nozzle. Note: As expansion ratio is increased the reach of the nozzle will be decreased due to the greater amount of bubbles in the stream and their inability to penetrate the air. Figure 9 gives approximate stream trajectory information with and without Foamjet LX. Actual results will vary based on brand of foam, hardness of water, temperature, etc.
     

11. Cleaning After Use
    After educting foam it is recommended that water be educted in through the concentrate hose and inlet. This will wash out foam concentrate residue in the hose, orifice plate, and nozzle passages. If not removed, any residue may dry and adversely affect the accuracy of proportioning.
     

12. Use with Salt Water
    Use with salt water is permissible provided nozzle is thoroughly cleaned with fresh water after each use. the service life of the nozzle may be shortened due to the effects of corrosion and is not covered under warranty.

Maintenance and Inspection

• Coupling and gasket are tight and leak free.
• The desired orifice plate (flow and percentage) is installed.
• Concentrate inlet hose and gasket are damage and leak free.
• Flow passages are unobstructed.
• Baffle is in place and tightened securely.
• Shaper moves freely.

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