ENGINE COMPANY OPERATIONS WITH STANDPIPES
Successful operations using standpipe systems for water supply require planning. Each building with installed standpipe systems must be surveyed, preferably by suppression companies normally on the firstalarm response. Locations of all connections, square footage of all fireloaded areas, distances to remote rooms from each standpipe connection, fire pump locations and the locations of their controls, and the type of valves and pressure-reducing devices on each floor must be recorded. Using these data, a strategic plan indicating fire-flow requirements for each floor as well as the amount of hose needed to reach all areas should be formulated for each building.
FIRE FLOW
After determining flow rates by using the Iowa formula (volume of space / 100 = gpm), the department should plan on providing companies with hoseline and nozzle equipment specifically designed to realistically supply the required flow. Designing an attack plan for standpipe use that is based on a department’s ground-level operations could be a deadly mistake. Standpipe hoselines are not simply “a preconnect in a bag.” Their use should involve a carefully planned system that balances realistic water flow delivery, compactness, and weight in a package that can be stretched in total darkness, if necessary, and advanced rapidly under high-heat, high-stress conditions.
The One Meridian Plaza fire reminds us to always plan for the worst-case scenario. In that fire, the power failed early, leaving the department with no elevators, lights, or fire pumps. The delayed alarm coupled with nonfunctioning upper floor elevators caused a substantial delay in the arrival of suppression personnel on the fire floor. Once they arrived, a combination of misadjusted floor hose valves and lack of a functioning building fire pump reduced the available standpipe pressure. We can see that operations should be designed around standpipe hose packs that can be carried long distances up stairs and should be capable of providing a large amount of water at low pressures.
Hose size should be determined by flow requirements. Remember, the larger the hose diameter, the less the friction loss, which could become a factor if low standpipe pressure is encountered. Many experienced departments such as Boston, New York, Houston, and Chicago use 2 1/2-inch hose for standpipe operations. In these departments, it is common practice for each company member to bring a single length, spreading out the total weight among the entire company. This system works fine for five-person companies but may not be practical for three-person companies, now common in many departments. For example, the use of lightweight, thermoplastic-lined hose can reduce the weight of standard double-jacket, rubber-lined hose by about half, allowing each member to carry 100 feet instead of 50 feet of line. Generally speaking, 2 1/2-inch hose will provide flows of from 250 to 325 gpm. However, its high weight when filled with water limits the ability of a twoor three-person crew to efficiently manage and rapidly advance the line.
The Los Angeles City Fire Department, after extensive testing, placed 2-inch lightweight hose into service specifically for standpipe operations. This hose allows members to easily earn 100 feet of hose, draped horseshoe-style on their backs over the breathing apparatus cylinders. Also, the couplings on this hose are beveled so they won’t hang up when pulled around corners. Utilizing lowpressure combination nozzles, their system easily can provide flows beginning at 200 gpm.
Depending on flow requirements, residual riser pressure, nozzle type, and length of the line, 1 1/4-inch hose can be used to provide flows around 150 to 180 gpm. Many departments are finding it more efficient to operate 2-inch or 1 4/3-inch lines together rather than a single 2 1/2-inch line.
Departments wishing to reduce line weight can specify lightweight hose made up in 100-foot lengths, which eliminates a set of couplings weighing about 2 1/2 pounds. If hose is supplied specifically for standpipe operations, it should be ordered with colored stripes or a colored jacket to differentiate it from standard attack hose.
In an effort to lighten the weight of the hose, some departments use single-jacket hose for standpipe operations. Remember that single-jacket hose is designed only to flow water, not to counter the effects of abrasion or heat. Dragging single-jacketed line over a debrisand ember-littered floor in a fire occupancy easily can cause failure by cutting and melting. And remember, it is not an easy matter to grab a spare length off the engine when you are 26 floors in the air. Excellent lightweight doublejacket hose, both woven and ruhbercovered, arc available—some specifically designed for standpipe operations.
HOSE PACKS
Hose packed for standpipe operations should be capable of being carried hands-free, either over the shoulder or draped over a breathing apparatus cylinder. Ideally, the hose should be situated as close to the carrier’s center of gravity as possible. This allows both hands to be used to assist in climbing stairs while helping keep the load and the firefighter in balance. Hose bags or packs requiring two firefighters to carry them may not prove practical when hose has to be hand-carried up many floors.
The simplest way to keep hose together is with individual straps with buckles or fabric strap fastenings. There are many commercially available high-rise hose packs, but remember that any pack should add very little weight to the total package, be capable of handling different sizes and lengths of hose (depending on conditions), and be capable of being unloaded easily in the dark. It is not necessary to totally enclose the hose within a heavy pack because hose abrasion during transport is not a factor, and the lack of ventilation can cause wet hose to mildew.
HOSE FITTINGS
If 1 3/4-inch or 2-inch hose is selected, the use of a gated wye on a short length of 3-inch hose with a 2 1/2-inch coupling, sometimes called a pigtail, can prove extremely efficient. In use, the 3-inch hose is connected to the standpipe hose valve and the valve is opened completely. One or two lines then can be stretched and the pressure-controlled by the wye valves, not the standpipe valve. If two lines are connected and operated together, the total flow can be approximately 370 gpm using 1 3/4-inch hose to 450 gpm using 2-inch hose, depending on nozzle equipment. This side-by-side operation could prove more versatile and effective than stretching a single 2 1/2-inch line.
A lightweight pressure gauge between the 3-inch line and the gated wye will help you evaluate standpipe conditions before an attack is mounted. If lower-than-standard pressure is indicated on the gauge, a switch to smooth-bore nozzles may be necessary to provide workable streams.
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NOZZLE EQUIPMENT
A nozzle used for ground-level attack at the end of a preconnected line may not he the best choice for use on the business end of a hoseline being supplied from a standpipe. Remember, a combination of fire pump failure, marginal standpipe design, the system’s age, valve misadjustment, debris in the system, corroded or unmaintained valves and other system components, and partially closed isolation valves all can reduce the pressure available at the floorvalve outlet.
At the One Meridian Plaza fire, the fire department estimated it had about 45 psi available on the fire floor, which is not high enough to properly activate the pressure control device in the automatic nozzles being used. Automatics are excellent firefighting nozzles when they are properly supplied and operated. Because of the many uncontrolled variables that could restrict available pressure in a standpipe system, they may not receive enough pressure to function properly in all situations.
Remember, automatic nozzles need approximately 100 psi for the pressure-control device to open and operate properly. Depending on the nozzle, if less pressure is available, flow and stream reach could be drastically reduced.
Many departments, while continuing to use automatic nozzles on standard attack lines, are switching to low-pressure combination nozzles or smooth-bore nozzles (or both) for use on standpipe lines because of their improved low-pressure performance. Departments in l-os Angeles and San Francisco, after extensive testing, now use 200 gpm low-pressure nozzles on all standpipe lines. Chicago uses a combination of lowpressure fog and smooth-bore nozzles, as do Miami and St. Louis. New York uses smooth-bore nozzles as standard. However, the officer carries a combination nozzle tip for use if needed for ventilation or in conjunction with smooth-bore streams for special situations.
All high-rise packs should include a smooth-bore tip, either for standard use or availability in low-pressure situations. What might work in the supplyand pressure-controlled environment of ground-level operations may not be suitable for use with low or fluctuating pressures. Ideally, a nozzle for standpipe use should be capable of generating an effective stream at low pressures, if higher than normal pressures are encountered, they can be gated by suppression personnel at the hose outlets.
Other items that should be immediately available are special adapters to allow connections to damaged threads, a wrench for if the floor valve handwheel is missing, a spanner wrench for removing house hoselines, extra door chocks, extra lighting, and a forcible-entry tool.
Strategic surveys of each building coupled with careful planning can help pave the way to smoother, more efficient, and safer operations, even under unusual or unplanned conditions.