Pumper Study Notes

Posted on Apr 19, 2024 in Other subjects

CHAPTER 2 (Types of Fire Apparatus Equipped with a Fire Pump)

Minimum Pump Capacity for Pumpers is 750gpm
Pumps larger than 750gpm have increments of 250gpm
Industrial Pumpers frequently have pumpers greater than 2000gpm
Municipal and Industrial foam pumpers may be equipped with: Around the pump, direct injection, balanced foam proportioning systems, compressed air-foam systems or a combination of all.
Most Industrial foam pumpers have large foam tanks from 500-1500gal.
Most common size foam tank for municipal fire apparatus range from 20-100gal.
Elevated water devices typically range from 50-75ft.
Mini-Pumpers are smaller, quick-attack pumpers that don’t require the capacity or personnel needed for a larger pumper, and have pumps up to 500gpm or less although some have up to 1000gpm.
Midi-Pumpers (interface Engines) are well-suited for nuisance fires such as small grass or trashbin fires, and fires that don’t require the capacity or personnel of a full-size pumper. They can have pumps as large as 1000gpm.
The main difference between a Mini- and a Midi- pumper are; size, pump capacity and the amount of equipment carried.
Single rear-axle truck should not exceed 1500gal of water.
Tandem rear-, tri- axle or tractor trailers are used for anything over 1500gal of water.
Tactical Tenders or Attack Tankers are capable of supplying water AND pump.
Wildland Fire Apparatus carry less than 500gal with pumps up to 1000gpm.
Pump & Roll operations use a separate motor or PTO.
Booster Tanks from Wildland Apparatus range from 20-1000gal
Apparatus Typing: Allows ICs to call for exactly the types of resources they need to handle the incident.
Fireboats can deliver have been built to deliver as much as 26,000gpm with individual master stream turrets that can deliver 2000 to 3000gpm.
NFPA 1901 states that the minimum pump capacity for an Aerial shall be 250gpm.
NFPA 1901 states that the minimum pump capacity for a quint be at least 750gpm.
Smaller Ladder Tenders are used when incidents don’t require a full size ladder truck. They’re quipped equipped with small tanks, pumps and booster hose that typically don’t produce more than about 300gpm.
Engine Tenders: Rescue Vehicles with smaller fire pump and tanks to handle small fires & provide protective hoselines at incidents. They generally have a pump capacity of 500gpm or less & carry 500gal of water or less.
The Inverter is a step-up transformer that converts 12-24volt DC current to 110 or 220volts AC current. They are generally capable of providing 1500Watts or more of electric power.
Portable Generators are designed with a variety of power capabilities with 5000watts of power being the largest.
Vehicle generators are larger than portable and can be powered by gasoline, diesel or propane engines, or by hydraulic or PTO systems and can provide up to 12,000watts of power.
Rescue vehicles have larger generators than do pumpers, with capacities up to 50,000watts.
ARFF aparatus are classified by: Agents carried, Agent Capacity, Number of drivewheels.
ARFF are divided into 3 classifications:: Major FF vehicles, Rapid Intervention Vehicles, Combined Agent vehicles.
Portable Lights generally range from 300 – 1000watts.

CHAPTER 3 (Intro to Apparatus Inspection & Maintenance)

Free-Play: The distance the pedal must be pushed before the throw-out bearing actually contacts the clutch release fingers.
Insufficient Free-Play (free-travel) will cause the clutch to slip, overheat and wear out sooner. The throw-out bearing will also have a shorter life.
Excessive Free-Play may result in the clutch not releasing properly. This can cause hard shifting, gear clash and damage to the gear-teeth.
Steering wheels should have less than 10 degrees of wheel-play in each direction.

Braking

NFPA 1901 requires apparatus to come to a complete stop from a speed of 20mph in a distance NOT to exceed 35ft on a dry, paved surface.
NFPA 1901 requires apparatus parking-brake to hold the apparatus in place on a 20% grade.
Air-brakes should build pressure to a sufficient level for vehicle operations within 60 seconds.
Apparatus with air brakes are to be equipped with an air-pressure protection valve that prevents the horn from being operated when air reservoir pressure drops below 80psi.
When testing Parking & Road brakes, the apparatus moves at 5mph and must come to a complete stop within 20ft.

Fluids/Battery

To select proper lubricant, consideration should be given to: The unit being lubed, the characteristics of the lube and manufacturers recommendations.
Charging a battery:
- Make sure battery and ignition switches are OFF
- Identify the polarity of the battery
- Attach the red cable to the red battery post, then the black cable to the black post
- Connect the charger to a reliable power source
- Set desired voltage & charging rate
- Reverse procedure to disconnect
The Inverter is a step-up transformer that converts 12-24volt DC current to 110 or 220volts AC current. They are generally capable of providing 1500Watts or more of electric power.
Portable Generators are designed with a variety of power capabilities with 5000watts of power being the largest.
Vehicle generators are larger than portable and can be powered by gasoline, diesel or propane engines, or by hydraulic or PTO systems and can provide up to 12,000watts of power.
Rescue vehicles have larger generators than do pumpers, with capacities up to 50,000watts.

Pump Daily Inspections

Operate the pump-drive control and make sure pump can be engaged.
Make sure the fluid level in the priming oil tank is full and that the siphon-break hole in the oil line, and the vent-hole in the oil-tank cap are OPEN.
Make sure the auxiliary fuel tank is full in the case of separate engine-driven pumps with fuel supplies independent of the main apparatus fuel tank.
Make sure all gauges and valves on the pump panel are in working order. Make sure that all pump drains are CLOSED.
Make sure that the fire pump and booster lines are completely drained of water to prevent damage from freezing in cold climate conditions.
Operate the controls to check or inspect a fire pump. It is not necessary to pump full capacity.
Inspect water and foam tanks for proper fluid level.
Check for damage, leaks or obstructions in any auxiliary winterization system.
Test roof and bumper turrets for proper operation and full range of motion.
Check all components of the auxiliary fire suppression systems on board (halon, dry chemical, etc) for damage, leaks, or corrosion.

Pump Weekly Inspections

Flush the pump with clear water if it is department policy to carry the pump full of water. Simply open the valves and drains and push water through the system until it runs clear and no debris is being discharged.
Check and clean intake strainers.
Check the pump-gear box for proper oil-level and traces of water.
Operate the pump-primer with all pump valves CLOSED
Operate the change-over valve while pumping from the booster tank in the case of a multi-stage pump.
Check the packing glands for excessive leaks.
Operate the pump-pressure control device(s).
Test the accuracy of the foam proportioning system.
Refer to the manufacturer’s recommendations for additional instructions, if any.

CHAPTER 4

(Operating Emergency Vehicles)

20 to 25% of all Firefighter deaths & injuries are caused by collisions.
25 Firefighter deaths per year are caused by collisions and rollovers.
An equal number of civilians are killed annually in apparatus-related collisions.
Collisions at intersections are by far the most frequent and most severe.
Poor road conditions, poor vehicle condition and failure to obey the traffic rules are often contributors to apparatus-related collisions.
Collisions are most likely to occur during ideal vision and road conditions.
Fire Apparatus collisions can be grouped into five (5) basic causes: 1) Improper Backing of Apparatus 2) Reckless driving by the public 3) Excessive speed by the Fire Dept. D/O 4) Lack of driving skill & experience by the D/O 5) Poor apparatus design or maintenance
A large percentage of collisions occur while backing the vehicle and account for a significant portion of overall damage costs.
Reckless driving by the public includes: 1) Failure to obey posted traffic regulations or directions; 2) Failure to yield to emergency vehicles; 3) Excessive speed; 4) Unpredictable behavior created by a panic reaction to an emergency vehicle; 5) Inattentiveness
There are a number of factors that may contribute to collisions that involve D/O error as the cause: 1) Overconfidence in one’s driving abilities. 2) Inability to recognize a dangerous situation. 3) False sense of security because of a good driving record. 4) Misunderstanding of apparatus capabilities. 5) Lack of knowledge about how to operate the controls of the apparatus in an emergency.
Excessive Speed may lead to one of the two types of collisions occurring: 1) Control of the apparatus is lost on a curve or adverse road surface which may cause the vehicle to leave the road surface, roll over or strike another vehicle; 2) The D/O is unable to stop the apparatus in time to avoid a collision with another vehicle or object.
There is a momentary lag before the air brakes commonly used on fire apparatus activate; therefore it may take slightly longer to stop a fire apparatus equipped with air brakes than a vehicle equipped with hydraulic brakes.
There are a number of factors that contribute to collisions that involve D/O error: 1) Overconfidence in one’s driving ability; 2) Inability to recognize a dangerous situation; 3) False sense of security because of a good driving record; 4) Misunderstanding of apparatus capabilities; 5) Lack of knowledge about how to operate the controls of the apparatus in an emergency
Unless equipped with a block heater, the apparatus should be idled as along as possible (3-5min in a non-emergency and a few second for emergencies) before putting it into road gear.

Starting the vehicle

Disconnect all ground shore lines or electrical cords, air hoses, etc.
Turn on the vehicle battery or batteries.
Start the Engine (Manual on (N) or Automatic on (N or P)). The starter should be operated in intervals of no more than 30sec with a rest of 60sec in between to avoid overheating the starter.
Observe the apparatus gauges. If the oil pressure doesn’t indicate a reasonable amount of pressure within 5-10 sec of starting the apparatus, stop the engine immediately and have the lubrication system checked by a trained mechanic.
Adjust the seat, mirrors and steering wheel if someone else drove the vehicle last.

Driving the vehicle

Once the apparatus is ready to move, the D/O should depress the interlock on the shifter and move it to the proper gear selection.
When climbing a hill, shift the transmission to a lower gear.
On sharp curves or when turning corners, shift standard transmissions into a lower gear before entering the curve or intersection.

Cruising

Do not try to reach rated speed in the lower gears,
Once at speed, stay in the highest gear that allows the apparatus to keep up with traffic and still have some power in reserve for acceleration.
Keeping the engine operating within its power curve ensures adequate power and optimum fuel economy.
Wherever possible, avoid overthrottling, which results in lugging. Lugging occurs when the throttle is applied while the transmission is in too high a gear for a given set of conditions.
Avoid allowing the engine to overspeed as the result of improper downshifting or hill descent in an effort to prolong engine life. Choose a gear that allows the engine to operate at 200 or 300 rpm lower than maximum recommended rpm.

Stopping the vehicle

Some apparatus employ engine brakes or other types of retarding devices that assist in braking.
The engine brake and retarder are activated when pressure is released from the accelerator. Because they provide most of the stopping action, these devices allow the D/O to limit the use of service brakes to emergency stops & final stops.

Engine Idling

Long idling periods can result in the use of ½ gallon of fuel per hour.
When the engine must be left idling for an extended period of time, set it to idle at 900-1200 rpm rather than lower speeds.

Engine Shutdown

Never attempt to shut down the engine while the apparatus is in motion because this cuts off fuel from the injectors.
Fuel flow is required for lubrication any time the injector plunger is moving.
Shutting down the engine without a cooling off period results in immediate increase of engine temperature from lack of coolant circulation, oil film burning on hot surfaces, and possible damage to the heads, exhaust manifold and turbocharger.
Allow the engine to stabilize before shutdown. Generally an idle period of 3-5 minutes is recommended.
The procedures for shutting down the apparatus are:
Place the transmission in (P) or (N)
Set the parking brake
Allow the engine to idle and cool down for 3-5 minutes
Shut off the engine by moving the ignition key or switch to the off position
Turn the battery switch to the off position
Reconnect all ground shore lines

Backing the vehicle

A significant portion of fire apparatus collisions occur while the apparatus is being driven in reverse.
Whenever possible, D/Os should avoid backing the apparatus. It is normally safer and sometimes quicker to drive around the block and start again.
Department SOPs should require that there be at least one FF – and preferably two – behind the apparatus to act as spotters.

Defensive Driving Techniques

Sound defensive driving techniques are one of the most important aspects of safe driving.
They include anticipating other drivers’ actions, estimating visual lead time, knowing braking and reaction times, combating skids, knowing evasive tactics and having the knowledge of weight transfer.
Motor vehicle laws in most jurisdictions provide that private vehicles pull to the right, stop and remain at a standstill until the emergency vehicle has passed.
Intersections are the most likely place for a collision involving an emergency vehicle.
When approaching an intersection, D/Os should slow their apparatus to a speed that allows a stop at the intersection if necessary.
Even if faced with a green light or no signal at all, the apparatus should be brought to a complete stop before proceeding slowly if there are any obstructions such as bldgs., or other vehicles that block the D/Os view of traffic approaching from either side.
Fire apparatus on an emergency may proceed through a red light or stop sign after coming to a complete stop and ensuring that all lanes of traffic are accounted for and yielding to the apparatus.
In some Depts. SOP requires that the street or road be blocked by law enforcement before apparatus are driven in an opposing traffic lane. Driving in the oncoming lane is not recommended in situations where oncoming traffic is unable to see the apparatus for any reason.
Visual Lead Time: Refers to the D/O scanning far enough ahead of the apparatus for the speed it is being driven to ensure evasive action can be taken if it becomes necessary.
Visual Lead Time interacts directly with reaction time and stopping distances.
Some Depts. train their D/Os to practice looking 12sec ahead in the city and 20sec ahead on highways.
Do not exceed 10mph when leaving the station.
Reaction Distance: The distance a vehicle travels while a driver is transferring the foot from the accelerator to the brake pedal after perceiving the need for stopping.
Braking Distance: The distance the vehicle travels from the time the brakes are applied until the apparatus comes to a complete stop.
Total Stopping Distance: The sum of the D/Os reaction distance and the vehicle’s braking distance.
Whenever a vehicle undergoes a change in speed or direction, weight transfer takes place relative to the rate and the degree of change.
The most common causes of skids involve driver error: 1) Driving too fast for road conditions; 2) Failing to properly appreciate weight shifts of heavy apparatus; 3) Failing to anticipate obstacles; 4) Improper use of auxiliary braking devices; 5) Improper maintenance of tire air pressure and adequate tread depth.

Traffic Control Devices

One of the simplest forms of traffic control involves placing a traffic signal in front of the fire station.
Another system for controlling traffic is the preemptive device. Some us strobe lights (emitters) mounted on the apparatus to activate sensors in the traffic lights.
Traffic control devices are NOT substitutes for using proper defensive driving techniques.

Braking Systems

Most newer apparatus are equipped with all-wheel ABS that minimizes the chance of a vehicle being put into a skid when the brakes are applied forcefully. The ABS monitors each wheel via more than 20x per second using digital technology and controls pressure to the brakes.
The first type of auxiliary braking system is Front brake-limiting valve; commonly installed before the mid 70s. Incorporated a “Dry Road/Slippery Road” switch and reduced the air pressure on the front steering axle by 50% when the switch was in the “Slippery Road” position. This would prevent the front wheels from locking up.
Some apparatus are equipped with frictionless Electromagnetic Braking Systems that augment and work in conjunction with the vehicle’s conventional brakes. They’re connected to either the drive shaft or the rear axle of the vehicle, and activate when D/Os remove their foot from the accelerator, step on the brake, or use a manual selector mounted on the steering column. They do NOT activate at speeds under 2mph.
Automatic Traction Control: Helps improve traction on slippery roads by reducing drive wheel overspin. ATC turns itself on and off. There is no switch for the D/O to select. Some vehicles equipped with ATC have a “Snow-and-Mud” switch. This function increases available traction on extra-soft surfaces. When the ATC is activated, the ATC indicator light flashes continuously. Deactivate when normal traction is regained.
In vehicles equipped with air brakes, there is a momentary delay (approximately .4 seconds) in the time from which the D/O pushes down on the brake pedal until sufficient air is sent to the brake to operate.
When an apparatus not equipped with an ABS system goes into a skid, the D/O should release the brakes, allowing the wheels to rotate freely. Turn the apparatus wheels into the direction of the skid.

Passing other Vehicles

It is best to avoid passing vehicles that are not yielding but if necessary, the following guidelines should be used:
Avoid passing vehicles on the right.
Make sure that you can see that the opposing lanes are clear of oncoming traffic if you must cross the center line.
Avoid passing other emergency vehicles if at all possible. If necessary, the lead vehicle should slow down and move to the right to allow the other vehicle to pass. This should be coordinated via radio if possible.

Adverse Weather

D/Os should recognize areas that first become slippery such as bridge surfaces, Northern slopes of hills, shaded spots and areas where snow is blowing across the roadway.
It takes 3 to 15 times more distance for a vehicle to come to a complete stop on snow and ice than it does on dry concrete.

Warning Devices and Clearing Traffic

At speeds above 50mph, an emergency vehicle can “outrun” the effective range of its audible warning device.
An emergency vehicle moving at 40mph can project 300ft in front of the vehicle.
At a speed of 60mph the siren is only audible 12ft or less in front of the vehicle.
When more than one emergency vehicle is responding along the same route, units should travel 300-500ft apart.
White lights can be readily distinguished during the daylight hours.
Warning lights, combined with on-scene floodlights, reduce the effectiveness of the reflective trim on FFs protective clothing and vests. In this situation it is desirable to turn off some of the warning lights once the apparatus is positioned to allow approaching vehicles’ headlights to more effectively illuminate the FF’s reflective trim.

Driving Exercises and Evaluation Methods

Alley Dock (12ft wide x 20ft deep): Tests the D/Os ability to move the vehicle backward within a restricted area and into an alley, dock, or fire station without striking the walls and to bring the vehicle to a smooth stop close to the rear wall.
Serpentine Course (cones between 30ft and 38ft apart): Simulates maneuvering around parked and stopped vehicles and tight corners.
Confined Space Turnaround (area at least 50ft wide x 100ft long): Tests the D/Os ability to turn the vehicle 180° within a confined space. There’s no limit to the number of direction changes performed.
Diminishing Clearance: (Narrows from 9.6” wide to 8’2” wide in 75ft long lane): Measures the D/Os ability to steer the apparatus in a straight line to judge distances from wheel to object, and to stop at a finish line. 50ft beyond the last stanchion, the D/O must stop the front bumper within 6” of the finish line.

Road Tests

NFPA 1002 says that any road test that leads to certification must include at least: 4 left turns & 4 right turns – A straight section of urban business street or two-lane rural road at least 1 mile in length – One through intersection and two intersections where a stop must be made – A Railroad Crossing – One curve either right or left – A section of limited access highway that includes an on-ramp, off-ramp and a section of road long enough for two lane changes – Downgrade that is step enough to require downshift and braking – One upgrade that is steep and long enough to require gear changing to maintain speed – One underpass or a low-clearance bridge

CHAPTER 5 (Positioning Apparatus)

Apparatus must be positioned so that its use is maximized and that interference with other unit is minimized.
Each type of apparatus should be positioned according to its intended function during an incident.
SOPs and sound judgment of the officer or D/O should be the deciding factors when committing/positioning the apparatus.
Determining the proper position of the attack pumper begins with sizing up the incident.
If the apparatus arrives at a location where no fire is evident, it is generally advisable to stop near the best access point in the occupancy, often the main entrance.
Considerations that influence apparatus placement are:
1) Department SOPs, 2)Rescue Situations, 3)Water Supply, 4)Method of Attack, 5)Exposures, 6)Wind Direction – position upwind and/or uphill (except for wildland fires) of the incident whenever possible, 7)Terrain – Always choose a paved surface over an unpaved surface, 8)Relocation Potential
A building’s collapse zone is equal to one and one half times the height of the structure.
When possible, position at the corners of buildings
Bulging walls, large cracks, falling bricks, blocks, or mortar and interior collapses are all signs that a serious exterior collapse may occur.
Inside/Outside method of positioning an apparatus: If a bldg. is less than 5 stories, the Engine is positioned closest (inside) to the building. If the building is more than 5 stories tall, position the Engine furthest (outside) and the Aerial closest to the bldg.
Pumpers providing water for elevated stream operations should position as close to the aerial as possible.
Pumpers should generally position as close to the sprinkler or standpipe FDC as possible.

Drafting Operations

Drafting Ops are required when a pumper is going to be supplied by a static water supply source such as a pond, lake, stream or cistern.
Preference should be given to drafting sites that are accessible from a paved surface and require a minimum length of suction hose or lift.
When placing intake hose directly into the static water source, the pumper should stop before reaching the source. First connect the hard intake hose and strainer to the pumper. Then drive the pumper into the final draft position.
The hard intake hose should not rest on the bottom of the water source during drafting.

Hydrant ops

Large diameter intake hose (aka soft sleeve or soft suction) is the preferred type of hose for connection to a fire hydrant and come in sections of 10 to 50 feet.
If the front wheels of the apparatus are turned to a 45° angle, the D/O can easily adjust the distance to or from the hydrant by moving forward or backward.

Side Intake Connections

A good way to minimize kinks is to put two full twists in the hose when making a connection to the hydrant.
Twists should not be put in the hose if either or both ends are equipped with sexless couplings.

Front and Rear Intake Connections

The D/O must stop the pumper either a few feet short or a few feet beyond the hydrant to permit the hose to curve.
When making a front or rear intake connection, the apparatus should be aimed or angled 45° or less in the direction of the hydrant.
When the maximum flow of a hydrant is not needed, or large diameter intake hose is not available, connection to the hydrant may be made with one or two 2 ½” outlets.
The main disadvantage of connecting to the 2 ½” outlet is that it is limits the amount of water that can be supplied.
During multiple intake connections, the pumper position should be determined by the soft-sleeve requirements because it is the shorter and greater capacity hose.

Dual Pumping Operations

With Dual Pumping, one strong hydrant may be used to supply two pumpers. (Rarely used).
The method for making a dual Pumping hookup is: Step 1: Pumper 1 connects to the hydrant steamer connection using large intake hose. This pumper then pumps water through its lines to the fire. – Step 2: Pumper 2 is positioned intake to intake with Pumper 1. If Pumper 1 is not equipped with a gate valve on its unused intake, the hydrant must be closed until the intake gauge of Pumper 1 reads 0, then the throttle adjusted. – Step 3: Pumper 2 is connected by intake hose to the unused large intake of Pumper 1 – Step 4: The hydrant is fully opened – Step 5: Pumper 2 pumps water through its lines to the fire. Its supply is the water not being used by Pumper 1 that is passing through it

Tandem Pumping Operations

Tandem pumping may be needed when pressures higher than a single Engine is capable of supplying are required.
Tandem pumping ops are also used when theattack pumper is positioned a relatively short distance from the hydrant, but a great distance from the fire.
To set up for Tandem Pumping: Step 1:Two engines may be positioned as much as 300ft apart. – Step 2: The Pumper directly connected to the water supply source pumps water through its discharge outlet to the intake of the second Engine. – Step 3:Tandem Pumping ops are actually a form of Relay Pumping, with the Pumpers positioned close together rather than evenly spaced in the supply hose layout. – Step 4:This enables the second engine to discharge water at a much higher pressure than on its own because the two pumps are acting in series.

Positioning Wildland Fire Apparatus

The two most common functions for wildland fire apparatus are providing structural protection and making a direct attack on a fire.
After life safety, the highest priority for most wildland firefighting operations is the protection of structures that are exposed to the fire.
The boundary between the wildland and structural development is often referred to as the Wildland/Urban interface.
Once the Engine reaches the structure it has been assigned to protect, it should be positioned so that it is safe and convenient from which to work. This can be accomplished by performing the following procedures:
Position the apparatus off the roadway to avoid blocking other apparatus or evacuating vehicles.
Scrape away fuel to avoid positioning in flammable vegetation.
Position the apparatus on the LEE side of the structure to minimize exposure heat and blowing embers.
Position the apparatus near (but not close to) the structure so that hoselines can be kept short.
Keep Cab doors and windows closed to keep out burning material.
Place the Engine’s AC in recirculation mode to avoid drawing in smoke from outside.
Do not place apparatus next to or under: Power lines, Trees, snags, LP Tanks or other pressure vessels or structures that might burn.
When the vehicle operates under conditions of reduced visibility because of smoke or darkness, it should be driven at an appropriately reduced speed.
A spotter (scout) may be needed to walk ahead of the vehicle to help locate and avoid obstacles such as logs, stumps, rocks, low-hanging limbs, ditches and gullies.
A short 1 ½” or 1 ¾” line should be deployed and charged for protection of the apparatus.
The apparatus should be parked facing the exit direction.
When apparatus is used in a mobile attack, hoselines should be kept as short as possible.
A small portion of water in the vehicle’s tank should always be reserved for protection of the apparatus and crew.
General engine-operation safety procedures are:
Engines should be positioned in a safety zone and should not be left unattended at fires.
Effective Communication with the rest of the fireground is critical
Headlights should be on whenever the Engine is running.
Engines should be backed into one-way roads and driveways, facing the escape route.
Always establish an anchor point prior to attacking a wildland fire.
Engines and crews should draw back to the flanks rather than attempt a frontal attack if the fire is spreading rapidly upslope.
Take advantage of natural breaks such as roads, and orchards.
Apparatus should not be driven into unburned fuels higher than the bumper or running boards without a spotter.
Crews should use areas of burned fuel whenever possible. Apparatus attacking from the unburned side must leave sufficient clearance distances from the fire line to allow for loss of water and mechanical failure.
Location of crews should be considered when moving apparatus. Do not drive into smoke where crews may be operating.

Positioning Support Apparatus

Rescue Apparatus

Rescue Companies: Sometimes referred to as Squads, are commonly used as extra manpower on the fire scene or to perform Truck Company functions in the absence of an aerial apparatus on the scene.
Positioning Rescue apparatus is not as critical as that of pumping. Rescue apparatus should be positioned as close to the scene as possible without blocking access to the other apparatus.
Rescue Apparatus should have a clear exit path from the scene in the event that it is needed at a second incident that might occur.

Command Vehicles

Command Vehicle: Or the incident Command Post (ICP) should be positioned in a fairly conspicuous location to all responders.
Ideally, Command Vehicles should be positioned near a corner of a building so that the IC is afforded a view of two sides of the building.
Driveways, parking lots, yards and cross-streets also make good locations for Command Vehicles.
Guidelines for positioning Command Vehicles are:
Provide maximum visibility of the incident and the area surrounding the incident
Place in a position that is easy to locate for other responders
Position in an area outside the immediate danger zone
Avoid blocking movement of other fire apparatus or incident operations.
Display some type of light or siren that identifies the vehicle as the ICP, such as pennants, flags, traffic cones, signs, banners, or flashing lights.

Breathing Air Supply Apparatus

Cascade systems are large breathing air cylinders that are connected together in banks and typically range from 4 to 12 tanks.
Cascade systems have limited duration of use before they themselves must be refilled.
Breathing-air compressors are engine-driven appliances that take atmospheric air, purify it and compress it.
Positioning of mobile air-supply apparatus is much the same as that for Rescue vehicles. The apparatus should be close enough to the scene so that Firefighters do not have to carry SCBA cylinders an extraordinary distance.
Apparatus using breathing-air compressors to refill SCBA should be positioned upwind of the fire in clear air space.
Some SOPs may require that breathing-apparatus to be positioned near the CP or in an area where FF rehabilitation is conducted.

EMS Vehicles

EMS vehicles should be positioned close to the scene but not so close that they block access for other emergency vehicles.
On incidents where there are patients requiring medical intervention, the IC should establish a triage and treatment area.
On incidents where there are no immediate medical problems to handle, the EMS vehicles and personnel will be in standby mode.
The most obvious location for EMS vehicles and staff would be in the area where FF rehab is being conducted.

Staging

An Apparatus staging protocol facilitates the orderly positioning of apparatus and allows the IC to fully utilize the potential of each unit and crew.
Level 1 staging is applied to the initial response to a fire or incident involving more than one responding company.
Hearing the Level 1 order, other responding units stage at least one block away from the scene in the direction of travel and await further orders.
Level 2 staging is used where a large number of emergency vehicles are responding to the same incident.
Incidents that require mutual aid or that result in multiple alarms need Level 2 staging.
Level 2 staging is initiated by the IC or Operations section Chief when requesting additional resources.
Generally, the company officer of the first company to arrive at the staging area becomes the Staging Area Manager.
Companies in staging must be ready to respond within three minutes of being called.
Apparatus arriving at the Staging Area should turn off all their emergency lights when they park.

Operations on Highways

Apparatus should not be driven against the normal flow of traffic unless PD units have closed the road.
Some apparatus are incapable of traveling as fast as the normal flow of traffic and using warning lights under these conditions may only create confusion and cause traffic conditions that slow the fire unit’s response.
Sirens should not be used except to clear slow traffic.
At the scene of highway incidents, a minimum of warning lights should be used to prevent blinding other drivers or distracting them.
According to the Manual of Uniform Traffic Control Devices, Emergency vehicle lighting should be used as needed to reach the scene, but once on scene its use should be reduced as much as possible.
Also consider positioning additional apparatus 150 – 200ft behind the shielding apparatus.

HazMat Incidents

First arriving apparatus should never be driven directly into the scene without the material involved being identified first.
The Hot Zone (also called the Restricted Zone, Exclusion Zone or Red Zone) is an area surrounding the incident that is closest to the release and may have been contaminated by the release material.
The Warm Zone (also called the Contamination Reduction Zone, Limited-access Zone, or Yellow Zone) is an area abutting the hot zone and extending to the cold zone.
The Cold Zone (also called the Support Zone or Green Zone) encompasses the warm zone and is used to carry out all other support functions of the incident.

Operating Near Railroads

Treat every railroad track as a potentially active line.
Never position the apparatus on the RR track as it may require hundreds of yards for a fully loaded train to come to a complete stop.
Keep the apparatus far enough away from the tracks so as not to be struck by a passing train.

EMS Incidents

More than 60% of calls to which most FDs respond to are EMS incidents.
It is important to allow the ambulance the best position for patient loading.
Many Departmental SOPs may require EMS vehicles to park off the street or highway and shut off all emergency lights.
Attempt to locate in a driveway, parking lot or yard.
Position the larger apparatus between smaller apparatus and the oncoming flow of traffic.
Guard the patient-loading area of the ambulance by shielding it with another vehicle.

CHAPTER 6 (What is Water and Where Does it Come From?)

Characteristics of Water

Water is a compound of Hydrogen and oxygen formed when two hydrogen atoms combine with one oxygen atom.
Between 32°F and 212°F, water exists as a liquid.
Below 32°F, it converts to a solid state of matter called ice.
Above 212°F, it converts into a gas called water vapor or steam.
Water is considered to be incompressible and its weight varies at different temperatures.
Water Density, or its weight per unit of volume, is measured in pounds per cubic foot.
Water is heaviest (62.4lbs/ft³) when it’s close to its freezing point.
Water is lightest (60lbs/ft³) when it’s closest to its boiling point.
For fire protection purposes, ordinary fresh water is generally considered to weigh 62.5lbs/ft³ or 8.33lbs per gallon.

Extinguishing Properties of Water

The primary way water extinguishes fire is by cooling, or absorbing heat from the fire. Another way is by smothering.
Water can be used to smother fires in combustible liquids whose Specific Gravity is higher than 1.
Specific Gravity determines whether water will float on the surface of another liquid or vice-versa.
As a smothering agent, water depends on :
Specific Heat
Latent Heat of Vaporization
Exposed Surface Area
Specific Gravity

Specific Heat and Latent Heat of Vaporization govern the heat-absorbing ability of water.
Specific Heat is a measure of the heat-absorbing capacity of a substance.
Water absorbs large amounts of heat. Amounts of heat transfer are measured in BTUs or in Joules.
A BTU is the amount of heat required to raise the temperature of 1lb of water by 1°F.
The Joule, also a unit of work, has taken the place of the calorie in the SI (International System of Units).
The Specific Heat of any substance is the ratio between the amount of heat needed to raise the temperature of a specified quantity of a material and the amount of heat needed to to raise the temperature of an identical quantity of water by the same number of degrees.
Latent Heat of VaporizationThe quantity of heat absorbed by a substance when it changes from a liquid to a vapor.
The temperature at which a liquid absorbs enough heat to change to vapor is known as its Boiling Point.
At sea level, water begins to boil at 212°F
Each pound of water requires approximately 970Btu of additional heat to completely convert to steam.
The speed with which water absorbs heat increases in proportion to the water surface exposed to the heat.
At 212°F, water expands approximately 1700 times its original volume.
Inside a burning building, steam expansion is not gradual but extremely rapid.
Viscosity is the tendency of a liquid to possess internal resistance to flow.
Specific Gravity: The density of liquids in relation to water. Water is given a value of 1. Liquids with a SG less than 1 are lighter than water and therefore float on water. Those with a SG greater than 1 are heavier than water and sink to the bottom.
Most flammable liquids have a Specific Gravity of less than 1.
The use of foam can control this situation because it floats on the surface of a flammable liquid and smothers the fire.

Water Pressure and Velocity

Pressure is defined as force per unit area, and may be expressed in psf or psi
Pressure can easily be confused with force.
Force is a simple measure of weight and is usually expressed in pounds or kilograms.
The weight of one cubic foot of water is approximately 62.5lbs.

Principles of Pressure

The speed with which a fluid travels through hose or pipe is determined by the pressure upon that fluid.
The speed at which this fluid travels is often referred to as Velocity.
There are six different Principles that determine the action of pressure upon fluids: First: Fluid Pressure is perpendicular to any surface on which it acts. – Second: Fluid Pressure at a point in a fluid at rest is the same intensity in all directions. – Third: Pressure applied to a confined fluid from without is transmitted equally in all directions. – Fourth: The pressure of a liquid in an open vessel is proportional to its depth. – Fifth: The pressure of a liquid in an open vessel is proportional to the density of the liquid. – Sixth: The pressure of a liquid on the bottom of a vessel is independent of the shape of the vessel.

Types of Pressure

Atmospheric Pressure is the pressure exerted by the atmosphere surrounding the earth. It is greatest at low altitudes and least at very high altitudes.
At sea level, the atmosphere exerts a pressure of 14.7psi, which is considered standard atmospheric pressure.
Any pressure less than atmospheric pressure is called Vacuum.
Absolute Zero pressure is called a Perfect Vacuum.
When a gauge reads -5psig, it is actually reading 5psi.
Head Pressure in the Fire Service refers to the height of a water supply above the discharge orifice.
To convert head in feet to Head Pressure, divide the number of feet by 2.304. The result is the Head Pressure in psi.
Static Pressure: Stored potential energy available to force water through pipe, fittings, fire hose, and adapters. Static means at rest or without motion.
Pressure in a water system before water flows from a hydrant is considered Static Pressure.
Normal Operating Pressure is that pressure found in a water distribution system during normal consumption demands.
The difference between static pressure and normal operating pressure is the friction caused by water flowing through the various pipes, valves and fittings in the system.
Residual Pressure is that part of the total available pressure not used to overcome friction loss or gravity while forcing water through pipe, fittings, fire hose and adapters. Residual means a remainder or that which is left.
Flow Pressure (Velocity Pressure) is that forward velocity pressure at a discharge opening while water is flowing.

Pressure Loss and Gain: Elevation and Altitude

Elevation refers to the center line of the pump or the bottom of a static water supply source above or below ground.
Altitude is the position of an object above or below sea level. Both are important in producing Fire Streams.
Both Pressure Loss and Pressure Gain are referred to as Elevation Pressure.
Altitude affects the production of fire streams because atmospheric pressure drops as height above sea level increases. This pressure drop is of little consequence to about 2000ft.
Above sea level, atmospheric pressure decreases approximately 0.5psi for every 1000ft.

Friction Loss

Friction Loss is that part of the total pressure lost while forcing water through pipe, hose, fittings, fire hose and adapters.
In a Fire Hose & Piping, the following cause Friction Loss: 1) Movement of water molecules against each other; 2) Linings (friction loss in old hose may be as much as 50% greater than new hose) – Inside surface of the piping (The rougher the inside of the pipe also called “Coefficient of Friction” the more Friction Loss occurs); 3) Couplings – Pipe Fittings; 4) Sharp Bends; 5) Change in hose size or orifice by adapters – Control Valves; 6) Improper gasket size

Principles of Friction Loss

There are four basic principles that govern friction loss in fire hose and pipes: First: If all other conditions are the same, friction loss varies directly with the length of the hose or pipe – Second: When hose sizes are the same size, friction loss varies approximately with the square of the increase in the velocity of flow – Third: For the same discharge, friction loss varies inversely as the 5^th power of the diameter of the hose – Fourth: For a given velocity, friction loss is approximately the same, regardless of pressure on the water
The size of the hose determines the velocity for a given volume of water.
Friction Loss increases as the length of hose or piping increases.
There are practical limits to the velocity or speed at which a stream can travel. If the velocity is increased beyond these limits, the friction becomes so great that the entire stream is agitated by resistance. This turbulence is called Critical Velocity.
Hose larger than 3” in diameter cannot be used for handlines.
Suddenly stopping water moving through hose or pipe results in an energy surge in the opposite direction, often at many times the original pressure. This surge is referred to a Water Hammer.

Principles of Municipal Water Supply Systems

A water system is composed of the following fundamental components: Source of Water Supply – Means of moving water – Water processing or treatment facilities – Water distribution system, including storage –

Two examples of surface water supply sources are rivers and lakes. Groundwater supply can be water wells or springs.

Three methods of moving water in a system are: Direct Pumping Systems – Gravity Systems – Combination Systems are a combination of direct pumping and gravity systems

Water Distribution System

A fire hydrant that receives water from only one direction is known as a dead-end hydrant.
When a fire hydrant receives water from two or more directions, it is said to have a circulating feed or a looped line.
A distribution system that provides circulating feed from several mains constitutes a Grid System.
A Grid System consists of:
Primary Feeders – Secondary Feeders – Distributors
In residential areas, the recommended size for fire hydrant supply mains is at least 6”. There should be 8” cross-connecting mains at intervals of no more than 600ft.
In the Business and industrial districts, the minimum recommended size for a fire hydrant supply main is 8” with cross-connecting mains every 600ft.

Water Main Valves

The function of a valve in a water distribution system is to provide a means of controlling the flow of water through the distribution piping.
Valves should be operated at least once a year to keep them in good condition.
Valves for water systems are broadly divided into Indicating and Non-Indicating types.
Indicating Valves: Visually shows whether the gate or valve seat is open, closed or partially open.
Valves in private fire protection systems are usually of the indicating type.
Two common Indicator Valves are the:
Post Indicator Valve (PIV), which is a hollow metal post that is attached to the valve housing and has the words OPEN and SHUT printed on them. These are commonly used in private water supply systems.
The Outside Screw & Yoke (OS&Y) Valve has a yoke on the outside with a threaded stem. The threaded stem is out of the yoke when the valve is open, and inside the yoke when the valve is closed. These are commonly used on sprinkler systems.
Nonindicating Valves in water distribution systems are normally installed in valve boxes or manholes. These are the most common type of valve used in the public water distribution system. They can be either gate or butterfly valves.

Water System Capacity

When Engineers design a water distribution system, there are three basic rates of consumption that they consider in their design:
Average Daily Consumption (ADC): The average of the total amount of water used I a water distribution system over the period of one year.
Maximum Daily Consumption (MDC): the maximum total amount of water that was used during any 24hr interval within a three year period. *This is normally about one and one-half times the Average Daily Consumption.
Peak Hourly Consumption (PHC): The maximum amount of water in any 1hr interval over the course of a day.

Private Water Supply Systems

Private water supply systems are most commonly found on large commercial, industrial or institutional properties, but may also be found in some residential developments.
In general, the private water supply system exists for one of the three following purposes: 1) To provide water strictly for fire protection purposes – 2) To provide water for sanitary and fire protection services – 3)To provide water for fire protection and manufacturing processes

CHAPTER 7 (Fire Hose Nozzles and Flow Rates)

A fire Stream can be defined as a stream of water or other extinguishing agent after it leaves a nozzle until it reaches the desired point.
Operating Pressures, Nozzle Design, Nozzle Adjustment, and the condition of the nozzle orifice influence the condition of the stream when it leaves the nozzle.

Fire Hose Nozzles

Solid Stream Nozzles (50psi handlines, 80psi Master Streams)

Determining the flow from a Solid Stream Nozzle: GPM = 29.7 x d² x √NP (29.7 is a constant, d is the diameter of the SS Tip and NP is the Nozzle Pressure given in psi).

Fog Stream Nozzles (100psi)

For a stream to be broken up into finely divided particles, it must be driven against an obstruction with sufficient velocity to break the surface tension of the water and shatter the mass.
Periphery – The line bounding a rounded surface.
Deflection – A turning or state of being turned. A turning from a straight line or given course. A bending; a deviation.
Impinge – To strike about or dash against; clashing with sharp collision; to come together with force.
A fog stream may be produced by deflection at the periphery, or by impinging jets of water, or a combination of these.

Constant Flow Nozzles (100psi)

Constant Flow nozzles are designed to flow a specific amount of water at a specific nozzle discharge pressure on all stream patterns.
Most constant flow nozzles use a periphery-deflected stream.
Most Constant Flow Nozzles are designed to be operated at a NP of 100psi, although some flow 50-75psi for high-rise fires.

Manually Adjustable Nozzles (100psi)

A refinement of the Constant Flow Nozzle, it has a number of Constant Flow settings, enabling a Firefighter to select a flow rate that best suits the existing conditions.
Most Manually Adjustable Nozzles are designed to be operated at a NP of 100psi.

Automatic Nozzles (100psi)

Automatic Nozzles: The most common Variable Flow Nozzles in use today. Also referred to as Constant Pressure or Multipurpose Nozzles.
Automatic Nozzles are basically variable flow nozzles with pattern-change capabilities and the ability to maintain the same Nozzle Pressure.
It should be the goal of every D/O to provide an acceptable flow of water at the discharge pressure for which the nozzle is designated.
Within its design limits, an Automatic Nozzle maintains a constant nozzle pressure of 100psi.

High Pressure Fog Nozzles (up to 800psi at 8-15gpm)

High Pressure Nozzles and lines are best used for fighting wildland fires and not recommended for structural firefighting.

Handline Nozzles

Handline Nozzles are to be placed on attack lines. They may be Solid, Fog, Impinging or Broken Stream.
Handline Nozzles range in size from small booster lines to large fog or solid stream on 3” lines.
350psi is the maximum amount of water that can safely flow through a handline.

Master Stream Nozzles (80psi Smoothbore & 100psi Fog)

The term Master Stream is applied to any fire stream that is too large to be controlled without mechanical aid.
Master Stream flows are usually 350gpm or greater.

There are four basic categories of Master Stream Devices:

Monitor

With a Monitor, the stream direction and angle can be changed while water is being discharged.

There are three types of Monitors:

Fixed (Deck Gun or Turret): Permanently mounted on apparatus
Portable: Can be carried to the location needed
Combination: Can be mounted on the apparatus or carried to where needed

Turret Pipe

A turret pipe is mounted on a fire apparatus deck and is directly connected to the pump by permanent piping

Deluge Set

Consists of a short length of large diameter hose with a large nozzle or large playpipe supported at the discharge end by a tripod
The direction and angle of the stream CANNOT be changed while the deluge set is discharging water

Elevated Master Stream (Solid Stream 80psi, Fog Nozzles 100psi)

Elevated Master Streams are those large capacity nozzles that are designed to be placed on the end of an aerial device
They may be permanently attached to the elevating platform and preplumbed aerials or they may be detachable
A Ladder Pipe is a master stream device used in conjunction with aerial ladders (attached to the rungs) and may be operated from the top or bottom of ladder
The power system to operate these master streams may be electric, hydraulic or pneumatic

Special Purpose Nozzles (Broken Stream)

Used for Chimney Fires, Basement Fires and fires in inaccessible places
Broken Stream Nozzles differ from fog stream nozzles in that fog streams use deflection or impinging streams to create a fog pattern, while broken streams are created when water is forced through a series of small holes
Broken Streams produce larger droplets of water than do fog streams, giving them better reach and penetrating power

Piercing Nozzles (also called Penetrating Nozzles)

Commonly used on aircraft firefighting and to apply water to areas that is otherwise inaccessible to water streams such as voids, attics or below lightweight roof systems
A piercing Nozzle ig generally 3-6ft hollow tube with a hardened steel point that houses an impinging jet nozzle capable of delivering 100gpm

Chimney Nozzles (100psi @ 1.5 – 3gpm)

Nozzle Pressure and Reaction

As water is discharged from a nozzle at a given pressure (called Nozzle Pressure), a force (called Nozzle Reaction) pushes back on the firefighters handling the hoseline.
Nozzle Pressure illustrates Newton’s 3^rd Law of Motion: for every action, there is an equal and opposite reaction.

Calculating Nozzle Reaction for Solid Streams Nozzles

NR= 1.57 x d² x NP

Where: NR = Nozzle Reaction in pounds

1.57 = A constant

D = Nozzle Diameter in inches

NP = Nozzle Pressure in psi

Calculating Nozzle Reaction for Fog Stream Nozzles

NR = 0.0505 x Q x √NP

Where: NR = Nozzle Reaction in pounds

0.0505 = A constant

Q = Total flow through the nozzle in gpm

NP = Nozzle Pressure in psi

*The (Q) in each formula above represents total water flow and is NOT to be confused with the value of Q=flow/100 used in Friction Loss

CHAPTER 8 (Theoretical Pressure Calculations)

Total Pressure Loss: Friction Loss and Elevation Pressure Loss

To produce effective fire streams, it is necessary to know the amount of friction loss in the fire hose and any pressure loss or gain due to elevation.
Friction Loss can be caused by a number of factors: Hose Condition, Coupling Condition, or kinks, The primary determinate is the volume of water flowing per minute.
Calculation of friction loss must also take into account, the length and diameter of the hoseline and major hose appliances attached to the line.
Elevation Pressure: Elevation differences such as hills, gullies, aerial devices, or multistoried buildings create pressure loss or gain.
Total Pressure Loss: The combination of Friction Loss and Elevation Pressure. This is NOT to be confused with Total Discharge Pressure, which also includes Nozzle Pressure.

Determining Friction Loss

There are two methods used to determine Friction Loss: actual tests and calculations. The most accurate of these methods determines friction loss through hands-on field tests.
Field Tests involve using inline gauges to measure friction loss at various flows through an actual hose layout. The Calculation Method involves the use of mathematical friction loss equations or field application methods.
The only truly accurate method for determining pressure loss in any particular hose lay is by measuring the pressure at both ends of the hose and subtracting the difference.

Determining your own Friction Loss coefficients Test results are only as accurate as the equipment used to measure the results: Pitot Tube – Two inline gauges – Hose to be tested – Smoothbore nozzle (if pitot tube is used) – Any type of nozzle (if using flowmeter): Step 1: Lay out hose on level surface (300ft if 50ft hose-lengths or 400ft if 100ft hose-lengths) – Step 2: Connect one end of the hose to a discharge on the pumper. Connect a nozzle to the other end – Step 3: Insert gauge 1 in the hoseline between first & sections of hose away from the discharge (50ft from discharge if using 50’ sections and 100ft from discharge if using 100’ sections) – Step 4: Insert gauge 2 at a distance of 200ft from gauge 1, regardless of hose length. *If using a portable flowmeter, DO NOT insert it anywhere between the gauges – Step 5: When all appliances are in place, begin the test. Supply water to the hoseline at a constant pump discharge pressure for the duration of each test run. – Step 6: Once water is flowing, record the pump discharge pressure, the readings from gauge 1 & 2, and the flowmeter or pitot gauge readings

Appliance Pressure Loss

Hoseline Appliances include: reducers, increasers, gates, wyes, manifolds, aerial apparatus, and standpipe systems.
*Appliance Friction Loss is insignificant in cases where the total flow through the appliance is less than 350gpm
*Assume a 0psi loss for flows less than 350gpm, and a 10psi loss for each appliance (other than Master Streams Devices) in a hose assembly when flowing 350gpm or more.
*For this manual, we will assume a friction loss of 25psi in all Master Stream appliances regardless of the flow.
Water exerts a pressure of 0.434psi per foot of elevation

Hose Layout Applications

Hose layouts include: single hoselines, multiple hoselines, wyed or manifold hoselines, and Siamese hoselines.
The combination of FL and EP is referred to as TPL

Simple Hose Layouts:

Single hoselines: The most commonly used hose lay. Presents the simplest FL calculations
Equal-length multiple hoselines: Only necessary to perform calculations for one line
Equal wyed hoselines: A common hose assembly usually using 2 ½-, 3-, or 4-inch hose wyed into two or more smaller attack lines.
Equal-length Siamese hoseline: To keep FL within reasonable limits, Firefighters may lay 2 or more parallel hoselines and ‘Siamese’ them together at a point close to the fire.

FL Formulas

Determining the gpm of a Smooth Bore when only diameter of tip and psi is given: GPM=29.7 x D² x √NP
Single Hoselines: FL=CQ²L
Multiple Hoselines: FL=CQ²L When both are the same diameter, perform calculation for only one. When they’re different diameters, perform calculations for each line, and set the pump for the highest pressure
Wyed Hoselines: Step 1: Compute the number of hundreds of gpm flowing in each wyed hoseline using Q=flow rate/100 – Step 2: Determine FL in one of the wyed attack lines using: FL=CQ²L – Step 3: Compute total number of hundreds of gpm flowing through the supply line to the wye using: Q-total = (gpm in attack line 1) + (gpm in attack line 2) / 100 – Step 4: Determine FL in the supply line using FL=(C)(Q-total)²(L) – Step 5: Add the FL from the supply line, one of the attack lines, 10psi for the wye (if the total flow exceeds 350prm) and the EP (if applicable) to determine TPL

Siamesed Hoselines: Must use DIFFERENT COEFFICIENTS for the Siamese Lines: Step 1: Compute the number of hundreds of gpm flowing in each wyed hoseline using Q=flow rate/100 – Step 2: Determine FL in the attack line using: FL=CQ²L – Step 3: Determine FL in the Siamesed lines using: FL=CQ²L (*With the DIFFERENT COEFFICIENT!) – Step 4: Add the FL from the Siamesed Lines, attack line, 10psi for the Siamese Appliance (if flow is greater than 350gpm) and EP (if applicable)

CHAPTER 9 (Fireground Hydraulic Calculations)

Flowmeters (FMs)

The ultimate purpose of all fireground hydraulic calculations is to discharge an appropriate amount of water from the nozzles being used to attack a fire
Rather than providing a readout of the pressure going through a discharge, MFs provide the waterflow in gpm
MFs are advantageous when supplying hoselines or Master Stream devices equipped with Automatic nozzles
MFs can make it possible for D/Os to pump the correct volume of water to the nozzle without having to know the length of hoseline, the amount of FL, or whether the nozzles are above or below the pump
NFPA 1901 allows MFs to be used of pressure gauges on all discharges 1 ½” to 3” in diameter
Discharges that are 3 ½” or larger may be equipped with MFs, but they must also have an accompanying pressure gauge
The MFs must provide a readout in increments no larger than 10gpm

Types of Flowmeters

All FMs are designed to “read” water flow
There are two basic types of FMs:
Paddlewheel: Mounted in the top of a straight section of pipe in such a manner that very little of the device extends into the waterway as it reduces problems of impeded flow and damage by debris. As water flows, the wheel turns, and a sensor translate the speed into flow measurement
Spring Probe: Uses a SS spring probe to sense water movement in the discharge piping. The greater the flow of water, the more the spring probe is forced to bend, sending an electrical charge to the display unit.
When properly calibrated, MFs should be accurate to a tolerance of +/- 3%. This means that the readout should be no more than 3 gallons high or low for every 100gpm
Each discharge equipped with a FM had a digital readout display mounted within 6” of the valve control for that discharge

Flowmeter Applications

If a Firefighter communicates that water volume at the nozzle has suddenly diminished but there is no reduction in the FM reading, it can be assumed that a hose has burst
Relay Pumping: Use of the FM during relay pumping makes it possible to feed a supply line without having to know the number of gallons of water flowing from the pumper receiving the water
As engine speed increases, so does the discharge and the gpm reading from the FM
Increase the engine speed until the FM reading no longer increases. This sets the pump at the correct discharge pressure to supply an adequate flow to the receiving pumper
Do not allow the incoming pressure to drop too much below 20psi
Standpipe Operations: It is difficult to determine where hoselines and nozzles are being placed in a multistory building
When a FM is used, the problem can be solved by determining the number and type of nozzles connected to the standpipe, adding the maximum rated flow for each nozzle flowing, then pumping the volume of water that matches this figure
It is important that D/Os be in communication with the FFs on the nozzle to ensure that nozzle pressures are correct

Hydraulic Calculators (HCs)

HCs allow the D/O to determine the pump discharge pressure required without having to perform mental hydraulic calculations.
There are 2 types of HCs: Manual or Mechanical: Operate by moving a slide or dial which the waterflow, size of hose and legth of lay are indicated. They are most commonly supplied to Fire Departments by hose and Nozzle manufacturers. Electronic: Some apparatus are equipped with these. They are speccialy programmed devices that allow the D/O to input the known information: water flow, size of hose, length of lay and any elevation changes. They may be portable or mounted.

Pump Charts

Pump Charts may be placed on laminated sheets carried on apparatus or on plates that are affixed to the pump panel.
The 1^st step in developing a Pump Chart is ID all nozzles, devices, and layouts used by the Department and enter them in the nozzle column.
*Round pump discharge pressure to the nearest 5psi

Hand Method (or “counting fingers” method) – Used for determining FL in 2 ½” hose.

Each finger is numbered at the base in terms of hundreds of gpm.
May also be used on 1 ¾” hose

Condensed “Q” Formula – Developed for Fireground ops in which FL can be determined for 2 ½”, 3”, 4” and 5” hose.

GPM Flowing (can be used for hoses other than 2 1/2″)

Permits FL to be calculated from the gpm flow and is applicable to both Solid and Fog streams.
A D/O needs to know only the flow in gpm from a nozzle at a specified pressure. Then by subtracting 10 from the 1^st two numbers of gpm flow, an accurate FL figure per 100ft of 2 ½” hose is obtained.
Flows less than 160gpm are seldom encountered through 2 ½” hose.