OVERCOMING COMMON WATER SUPLY PROBLEMS

OVERCOMING COMMON WATER SUPLY PROBLEMS

BY DOUG LEIHBACHER

Establishing a water supply and putting hoselines into operation form the foundation of the firefighter`s craft and the basis of a successful firefighting operation. When these tasks go smoothly, other fireground duties can be performed safely and in a timely manner. The success of the overall operation often rests in the skilled hands of the firefighters who put the initial hoselines into operation.

Although there is always pressure to perform a hose stretch swiftly, it must be done carefully, assiduously, and methodically. Moreover, stretching hose requires patience, diligence, and attention to detail in an environment replete with distractions and other demands. Stretching hose is not simply a matter of grabbing the nozzle and running to the fire. Many obstacles will be encountered. Hose must be looped around car tires, thrown over fences, carried through doorways, and pulled around stair railings. It must be stretched in such a way that it will provide a steady, dependable water supply that won`t be lost. The responsibility for establishing a good hose stretch is shared by all company members. Although many difficulties may be encountered, stretching hose should not be a “drag.” Most difficulties are avoidable if we get back to basics. The following scenario illustrates the common and avoidable causes of water loss.

SCENARIO

An alarm has been transmitted. You are walking across the apparatus floor to the engine. As the doors go up, you pull your coat on and listen to the dispatcher giving additional information over the radio speaker: “All units, be advised we have several reports of heavy fire in a garage next to the house. Flames are extending across an open breezeway between the garage and the dwelling. All occupants have exited, but the house is severely threatened.”

This is your first fire at Engine 2, having just transferred there from Engine 3. There is a strong rivalry between the two companies, and you are anxious to do a good job at your new company. As you climb onto the engine, your lieutenant directs the driver to let the ladder truck pull out ahead of the engine so that it will have access to the front of the building.

En route, you overhear the lieutenant and the driver discussing hydrant locations in the cab amidst the cacophony of sirens and air horns. You can smell the smoke several blocks away and reach for your SCBA.

The ladder arrives first and confirms a heavy fire condition in a two-story wooden barn. The engine slows and stops at a hydrant a block before the address, but before the hydrant person can get off, the captain on the ladder calls your lieutenant over the portable radio to advise him that there is a hydrant in front of the fire building. With this information, the engine continues in.

Stopping in front of the driveway, you note that the wooden barn is fully involved and flames are rolling out the wide entrance door across a small driveway and up against the second-story windows of the main house. Instinctively, you climb down and reach for the 134-inch preconnect, but your lieutenant adroitly calls for the 212-inch line. As you pull it from the hosebed, the driver moves the apparatus forward to the hydrant, and all five preconnected lengths come off the hosebed and fall into the street. You sling your arm through the three top folds of the hose and stretch it down the driveway toward the barn. Once in position, you flake out the first length of hose behind the nozzle.

The ladder company, which has already reached the second floor of the exposed house, reports that fire has not yet extended into the house. As the lieutenant arrives at your side, the windows of the house break from the radiant heat; extension seems imminent.

With time of the essence, the lieutenant radios the pump operator and orders him to charge the 212-inch line immediately with “on-board” water from the 500-gallon tank before hooking up the hydrant. This will give you about two minutes of working time to contain the flames. Moments later, the line fills with water under your arm and, as you crack open the nozzle to bleed out the air in the line, the force of the water pressure tips the nozzle up and pulls you backward against the straight arm of the lieutenant and another firefighter who are crouching behind you, although they are almost obscured by smoke.

The lieutenant directs you first to give a quick dash of water onto the exposed house and then to train the water into the flame zone of the fire rolling out of the garage. After 20 to 30 seconds, the fire begins to darken down and you move closer to the barn, pulling the hose forward several feet. As you begin to direct the stream deeper into the barn toward the seat of the fire, the nozzle pressure drops to little more than a trickle. The lieutenant directs you to shut off the nozzle and disconnect it to see if it is clogged. As you do so, the heat and flames return to their original intensity. You shake out the nozzle, quickly reconnect it, and open the line, but there still is not enough water and your new position becomes almost untenable.

The flames are again impinging against the house, and your lieutenant orders you to back up to your original position. He calls the pump operator for more pressure, but as soon as the pump operator boosts the pressure, the line bursts near the back step of the pumper back in the street. Now there is no water to be had. However, your former squad mates at Engine 3 arrive with a line off their pumper and take over for you. It is lucky they arrived when they did. Knowing the ribbing you will be in for from your former colleagues, you are determined to find out what went wrong so it can be avoided in the future.

WHAT WENT WRONG?

Several things can cause a sudden loss of water pressure at the nozzle:

There is a kink in the hoseline.

The hoseline is pinched beneath a door.

Debris is clogging the nozzle or a pump intake valve.

A length of hose has burst.

The pump operator made a mistake.

The pump failed.

The relief valve was improperly set.

Kinks

A kink in the hoseline is one of the most common causes of loss of water pressure at the nozzle. Kinks occur invariably when hose is stretched. The sharper the bend, the more the water is reduced. Most kinks will reduce flow by 20 to 30 gpm. In the scenario cited above, a moderate kink in a pile of hose near the pumper tightened as the line was advanced until it completely occluded the water. At the moment the pump operator throttled up to give more water, the hydrant was opened. That combination increased the pump discharge pressure above 200 psi, and the line broke at the weakest point, a sharp kink at the rear of the pumper.

Who is responsible for making sure there are no kinks in the line? As a rule, the pump operator is responsible for all hose in the street, between the discharge port and the front door. The nozzle team is responsible for all hose inside the building, extending from the front door to the point of operation.

As the pump operator, you should not charge any hoseline before making a visual check. First, see that all the hose has been pulled out of the hosebed if using preconnected lines. Second, make sure that it is not lying in a pile near the back step of the engine. The nozzle team is focused on getting the line into operation inside the building and will disregard any excess line left in the street. Once all the hose is out of the bed and the kinks have been removed in the street, the hoseline can be charged. This may not be an easy task with supply lines lying everywhere and the officer calling for water, but it is crucial.

The nozzle crew is responsible for “flaking out” the working length of hose that was brought to the point of operation. The nozzle crew is not ready for water until the excess hose has been flaked. The choices for placing this extra hose include downstairs, upstairs, out the window, or into an adjoining room or apartment. Depositing the excess line upstairs is often preferred so that line advancement is aided by gravity. However, if you are going up with it, be sure the forcible entry team has control of the door so that you don`t find yourself inadvertently above the fire.

This doesn`t account for the hose on lower floors or near the front door. A second member of the hose team is often invaluable in feeding hose up the stairwell and making the stretch fast, smooth, and kink-free. Unfortunately, staffing does not always provide for a “kink-chaser,” and the task of straightening out the kinks in the stretch below the fire floor belongs to the nozzleman or the hydrant man on the way into the building. Though time is of the essence, this task cannot be overlooked. Often, the nozzleman must go back down a flight of stairs and pull up or flake out excess hose piled in the stairway, wellhole, or lobby. The excess hose is often needed during the operation and will be easier to retrieve if it is flaked out along the stair treads and landings.

A wide wellhole will allow for a fast stretch right to the fire floor. In addition, only one length will be needed to reach the fourth or fifth floor. However, this tactic may leave additional hose to be flaked out on the fire floor. It may also necessitate the use of a hose strap on the banister to control the weight of the hoseline once it is charged. A length of 134-inch line weighs about 80 pounds when it is charged. A 212-inch line weighs 155 pounds per charged length.

It is also important for the company officer to call for the right amount of hose. Having 100 feet of extra hose in the hallway is too much to distribute without kinking. While it is better to err on the side of stretching too much hose instead of not enough (stretching short), the overestimation should not be more than one 50-foot length. The officer must estimate how much hose will be needed from the pumper to the front door and from the front door to the fire floor, plus one working length. To make an accurate estimate, the officer must note which floor the fire is on, assess the distance from the pumper to the building, and size up the wellhole. An accurate estimate of how much hose is needed, a careful stretch, and a quick check by the pump operator before charging the line can eliminate the kinking hazard.

Doors

It is possible to do everything listed above and still not get any water because the hoseline gets pinched beneath a door or the gate of a fence. While dry, the line lies flat, and it is easy for a door to close over it. When the line is charged, the door acts like a shoe clamp, and it becomes impossible to move the line or the door unless the line is shut down at the pump and drained. To avoid this potentially dangerous situation, it is imperative to securely chock every door through which a line is stretched. A smoke explosion or backdraft can forcibly close an unchocked door over a charged hoseline, leaving the nozzle crew in a very tenuous position with no water. For this reason, all engine personnel should carry two door chocks.

Debris in the Water Supply

All manner of flotsam and jetsam can be found in the municipal water supply. The debris can be numerous and varied. It includes but is not limited to plastic bags, gravel, balls, candy wrappers, coffee cups, and balloons. These items are frequently found blocking nozzles and pump intake-port screens to the amazement of firefighters, who wonder how they got any water at all. Flushing the hydrant before charging the supply line can help prevent this occurrence. However, in spite of precautions, debris can often work its way along the supply line, through the pump, and up to the nozzle. Fog-type nozzles are more vulnerable to this type of mishap than smooth-bore nozzles. However, if equipped with a break-away tip, the nozzle can be shut down momentarily at the point of operation and the tip can be removed and examined. If a shutoff is not used with the nozzle, the problem is compounded. Briefly change the setting to “flush.” If that doesn`t clear it, it will be necessary to back out and have the water shut down at the pump to examine the nozzle.

Sometimes the debris never makes it through the pump all the way to the nozzle. Instead, it gets caught in the screen on the pumper`s intake port. A problem here is not always easy to pinpoint. The supply to the intake port will look fine. The only indication of a blockage may be found on the pump panel`s intake gauge. If an initial intake pressure drops dramatically or draws a vacuum without supplying any additional discharge lines, there may be a blockage. In this case, the hydrant will have to be shut down so the intake port can be cleared. A hydrant gate on the supply line will certainly come in handy here. If you must shut down, be sure to notify the crew on the handline that the water will be interrupted so they can take precautions.

A policy of taking five to 10 seconds to flush the hydrant barrel or standpipe riser before charging the supply line can help prevent this problem. Once flushed, the hydrant must be opened all the way. Two or three turns are usually not sufficient to open a hydrant fully and will leave the drain valves open in a dry-barrel hydrant.

Another way to compensate for a clogged intake port is to stretch two supply lines from the hydrant and attach them to different intake ports. In this way, if one line becomes nonfunctional, there is still a viable supply line.

Burst Lengths

A burst length of hose will usually put a line out of commission. Burst lengths are caused by a number of factors in addition to kinking. Often broken glass, associated with ventilation procedures, is the culprit. Be careful when stretching a line from a fire escape or ladder through a broken window. Remove all shards of glass from the sash. With thermopane windows, you can do this easily by pulling the gasket away from the sash. Another practice that can help to prevent burst hose is to shut off the nozzle slowly. Rapidly shutting the nozzle causes a water hammer. Similarly, the pump operator should open and close pump panel valves slowly.

When a line does burst, alert all crew members. If a hose jacket is available, bring it to the break and install it. Otherwise, you will have to shut down and replace the deficient length. Annual hose testing can reduce the frequency of this problem somewhat. Remove from the apparatus and send out for repair hose that is sprouting leaks or lengths with worn jackets. Doing this will prevent a mishap on the fireground.

The average service life for a 134-inch hoseline is five years under normal conditions. For a 212-inch line, it is 10 years. Consider unreliable hose that is beyond its normal service life. Keep in the company office a record for each length of hose so that age and repair history can be tracked. Monthly, remove and repack hose that has been idle in the hosebed so that the locations of sharp bends can be repositioned.

Pump Operator Error

When the pump operator makes an error, the entire fireground operation can come to a grinding halt. Every new pump operator worries about being able to supply enough water to the crew inside. (For a full discussion of troubleshooting for the pump operator, see my article in The Engine Company, Fire Engineering, January 1994.) Several common mistakes can slow water to a trickle. If you can`t give the crew water, check the following:

Make sure the engine is in pump and the transmission is in the proper gear.

If operating from a hydrant, be sure to open the intake port.

Make certain you are charging the right discharge line.

If operating with tank water, be sure you have opened the “tank to pump” valve.

Remember to switch to volume when pumping over 50 percent capacity.

Be sure all the hose has been pulled out of the hosebed. If the “hose basket” is charged, the hose will be so badly kinked that no appreciable water will flow to the nozzle. As stated above, check to see that all the hose is off before you charge it.

Pump Failure

Pump failure is rare. Most pump operators will never have to deal with it. However, if for any reason you are unable to use the pump, it is always possible to run off hydrant pressure. In this case, with the pumper near the fire, the pump takes on the role of a manifold from which handlines can be derived from a water source. If pressure from the hydrant is low, add an additional large-diameter supply line to reduce friction loss, and consider a relay or tandem pumping operation.

Relief Valves

Occasionally, pump operators will switch to hydrant pressure and lose a great deal of water pouring out from beneath the rig. The cause of this is usually open drain valves that must be closed. Another cause can be an improperly set relief valve. The relief valve setting can be checked at the fire station by flowing water through the booster reel and revving up to check the setting on the relief valve. Settings may occasionally change as a result of being loosened by jostling. The relief valve should be set according to the manufacturer`s recommendations or company SOPs. Some procedures call for setting the relief valve at each incident.

Being mindful of these potential pitfalls and their remedies can lead to successful operations even when you do not have enough personnel to go around. As noted, stretching a hoseline properly requires patience, diligence, and attention to details. On the fireground, the tortoise often wins the race.

This discussion bring to mind a story a 30-year veteran firefighter used to tell “the new guys.” It describes a common experience he used to have so often that it began to seem like a recurring nightmare to him. As he told it, the scene would be an upper-floor multiple-dwelling fire. He would be assigned to hand stretch a 212-inch hoseline up the interior stairs. As he would begin making his way up the stairwell with both arms full of hose, he would immediately be trampled by civilians pushing their way out of the building. Just as he would regain his footing and start climbing up the stairs, the first-due truck would arrive and push him aside. They didn`t have time to help him with the hose because they had to get upstairs to the fire apartment and force the door. About the time he`d get his balance, the second-due truck would knock him aside. They couldn`t give him a hand with the stretch because they had to get to the floor above the fire. Once they had passed, he`d resume his trek a little bit farther when the rescue would push past him. They couldn`t help him stretch the line because they had to make a search.

Just as he would finally struggle his way to the landing below the fire floor, he`d know what was coming. He`d hear some loud cussing from above. “It`s hot! Where`s that hoseline? What`s taking so long?” Soon came another trampling as everyone piled down the stairs from above, finding it a bit untenable without a hose stream.

The moral of this story is that stretching a hoseline takes time and must be done right. The nozzle team, the hydrant man, the pump operator, and the company officer all share in the responsibility of establishing a dependable water supply. When it comes to putting a hoseline in operation, many hands make light work. That`s why it is always appreciated when someone lends a hand by lightening up, placing a chock, or taking out a kink. That help can mean the difference between a successful operation and one that falls short. n

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A lieutenant calls for more water as firefighters direct a 212-inch exposure line onto an exposed wood frame building across a narrow alley. If flow to the nozzle is interrupted or diminished, the exposure building will be in severe jeopardy. (Photo by Paul Fialkovic.)

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(Top left) A kink in a hoseline can substantially reduce the effectiveness of a hose stream. A firefighter coming on a kink should take the time to straighten it, if possible. (Photos by Thomas K. Wanstall.) (Bottom left) Following a fire in a standpiped building, the operator of a clogged nozzle found this debris in the nozzle`s screen: magnetic cassette tape, a candy wrapper, and a plastic cap. (Right) Water pressure tends to enlarge the size of a burst in a hoseline. A damaged length is not dependable and should be replaced.

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