With the advent of the Interstate Highway System in the 1950s came the inevitable consequence of suburban sprawl. As populations shifted from older inner cities to the suburbs, developers realized the need for mega-malls, office buildings, hotels, high-rack storage warehouses and high-rise apartment buildings.
Photo by Lance Peeples
A Class I standpipe located in a fire-resistive stairwell can greatly aid fire department operations in a high-rise building.
For the fire service, the sheer size or height of these buildings frequently precludes the use of attack lines advanced from the hose beds of engine companies located in the street. Since many of these structures are now located in jurisdictions where engine companies are staffed by as few as three firefighters and truck company support is practically non-existent, firefighters must become familiar with standpipe operations if they wish to be effective in these occupancies.
Firefighters must know the location of all standpipes, which can be accomplished through pre-planning. In the event that a jurisdiction is unable to pre-plan all of the buildings which may be equipped with standpipes, it is helpful for the firefighter to be familiar with code requirements in their area. For example, the 1990 BOCA code requires that standpipes be installed where any point in a building is greater than 30 feet above or below where fire apparatus can be spotted. Additionally, standpipes are required if any point is greater than 400 hundred feet from where fire apparatus can be located.
There are many exceptions built into these codes and consequently the firefighter should study local code requirements to avoid surprises. The National Fire Protection Association (NFPA) publication, Fire Protection Handbook, in a section on "Standpipe and Hose Systems" identifies three classes of standpipes that firefighters should be familiar with:
Class I. Provides 2 1/2-inch hose connections for use by trained firefighters.
Class II. Provides 1 1/2-inch hose connections and hoseline for use by building occupants. Use is declining because of concerns about having occupants attack fires.
Class III. Combines the features of Class I and Class II systems, usually by using a 2 1/2-by-1 1/2-inch reducer. The use of Class III systems is also declining because of concerns about the wisdom of having occupants attack fires.
In addition to the above classes of standpipes, FDNY Captain and Firehouse Contributing Editor John Norman (in his book, Fire Officer's Handbook Of Tactics) says systems can also be categorized as:
- Dry. No water is present in the piping.
- Preaction. A dry standpipe where water is admitted by activating a pull box which sounds the alarm and trips a deluge valve.
- Wet. Water is always under pressure and available in piping.
Having described the basic types and classes of standpipe systems, the firefighter must also know the sources of water supply available to standpipe systems. These include municipal water mains, gravity tanks, pressure tanks and fire department connection.
Photo by Lance Peeples
Fire department connections can easily be rendered useless by foreign objects or damaged threads.
According to NFPA 14, Class I and Class III systems must be capable of delivering 500 gpm for the first standpipe plus 250 gpm for each additional standpipe, up to a maximum of 2,500 gpm. The system must be capable of sustaining this flow for 30 minutes. Additionally, NFPA 14 requires 65 psi residual at the topmost outlet while flowing 250 gpm from each of the two topmost hose connections.
Now that we have familiarized ourselves with the basic types of standpipes and their water supply requirements, it remains for us to discuss how to use these systems to our advantage, i.e.: "to put the wet stuff on the red stuff."
The first order of business is assembling a "standpipe pack." According to Danbury, CT, Fire Captain David Fornell, "Departments experienced in high-rise operations say that nothing less than 2 1/2-inch hose should be used. Companies carrying 1 1/2-inch single jacket rack hose coupled to plastic low flow nozzles for high-rise operations should expect high fire losses as well as increased injury rates for both firefighters and occupants" (Fire Stream Management Handbook).
Some readers may throw up their hands at this point and say, "We don't have the manpower to advance a 2 1/2-inch line." But the fire doesn't care. If the fire requires 200 gpm to darken down, then that's what it takes. Furthermore, if only 65 psi residual is available at an outlet, it's obvious that a 1 1/2-inch line with a 100-gpm nozzle rated at 100 psi is doomed to failure. As Fornell notes, "For high-rise use, thermoplastic-lined hose is an excellent replacement for standard-construction, double-jacketed hose. In this example, 100 feet of thermoplastic-lined 2 1/2-inch hose weighs six pounds less and provides a smaller pack than 100 feet of rubber-lined 1 3/4-inch hose. The 1 3/4-inch hose and low-pressure nozzle could be expected to provide an average flow from 125 to 160 gpm. At the same standpipe pressures, the 2 1/2-inch lightweight hose with 1 1/8-inch smooth-bore nozzle will flow over 250 gpm."
"But what about nozzle reaction?" the naysayers will cry. "I've only got myself and one other guy available to advance the line!" To counter this argument, Fornell offers the following tip sizes and their resultant flows, nozzle reaction and friction losses:
|1/2"||50 psi||20lb.||53 gpm||2 1/2"||1/2 psi|
|3/4"||50 psi||44lb.||118 gpm||2 1/2"||2 1/2 psi|
|1 1/8"||50 psi||99lb.||266 gpm||2 1/2"||15 psi|
|Fog||100 psi||76lb.||100 gpm||1 1/2"||25 psi|
|Fog*||75 psi||44lb.||100 gpm||1 1/2"||25 psi|
If it is assumed that a firefighter can safely handle one-half his or her body weight in nozzle reaction force, two firefighters should be able to briefly manage a 1 1/8-inch tip at 50 psi, flowing 266 gpm (in theory, at least but get help fast).
If low residual pressures are found on the system, the use of a smaller three-quarter-inch or half-inch "stacked tip" may allow the company to develop an adequate fire stream with minimal friction losses in the 2 1/2 -inch hose.
As a final argument against the use of 2 1/2-inch standpipe hose, some will suggest, "We'll just pump into the fire department connection, that will give us all the pressure we need." This argument fails to address the following concerns:
- The fire department connection may be out of service due to damaged threads, obstruction with foreign objects, etc.
- In extremely tall buildings, head pressure may be excessive.
- Pressure-regulating devices may be present at hose outlets. These should be removed and pressure maintained by manually controlling the outlet valve, if possible.
- Supply lines to the fire department connection are frequently cut by falling glass.
In short, the wise fire department will plan for the worst-case scenario a huge fire on an upper floor, the fire pumps are out and the fire department connection has a tin can jammed in it. Bring the 2 1/2 -inch thermoplastic hose with an 1 1/8-by-half-inch anodized aluminum "stacked tip." There's a lot at stake here; leave the 1 1/2-inch hose on the truck.
Photo by Lance Peeples
A Class III standpipe located in an enclosed stairwell. If occupants advance a hoseline into the hallway and then retreat, the stairwell door is blocked open. This could severely threaten occupants above the fire. The use of Class III systems is declining because of concerns about the wisdom of having occupants attack fires.
How much 2 1/2-inch hose should we bring? The "actual length" method for determining hose connections as described in the Fire Protection Handbook requires hose connections "such that enough connections are provided to reach all portions of the area served with a 100-foot hose that has a nozzle with a 30-foot reach." However, if the Class III outlet is in the public hall, that would necessitate making the connection on the floor below the fire. In fact, it is always good practice to make the connection on the floor below the fire. This allows the control valve to be adjusted without being subjected to heat and smoke. Caution would suggest that we make allowance for unforeseen complications i.e.: poor stream reach, scissor stairs, wrong stairway, etc. Consequently, it would appear that four lengths should be carried in initially. According to Norman, other items which may prove useful are spanner wrenches, hose thread adapters, a 10-inch pipe wrench (in case valve hand-wheel is missing), door chocks and door latch markers.
Now that we've assembled the necessary equipment into a standpipe kit, it only remains for us to discuss how to use it.
The first problem that usually presents itself is finding the fire. If detection devices have transmitted the alarm, it is usually a simple matter to begin the search in the zone in which the alarm has sounded. However, access or convenience stairs may allow a fire on a lower floor to activate a detector on an upper floor. If firefighters take the elevator to the floor below the alarm, they may actually be reporting to the fire floor. Get off the elevator at least two floors below the suspected location of any fire.
If building occupants report the location of the fire as being Apartment 1111, the company officer should stop at the 10th floor and locate Apartment 1011. By counting the doors back to the stairway, the officer knows which way to turn and how many doors must be passed before reaching the fire door. That also assures the officer that he can also assure himself that the stairwell nearest the fire apartment has been chosen.
While the officer completes the size-up, another member connects the attack line to the outlet on the floor below the fire. Before connecting the hose, however, the firefighter probes the outlet to make sure there is nothing stashed there and should remove any pressure-reducing devices. Once the line has been connected, any excess hose should be flaked up the stairway, so as to allow gravity to assist in advancing the line. When the officer returns, the line can be charged and any excess air bled off. Upon the arrival of the forcible entry team from the truck company, it is a simple matter of advancing the line from the stairwell into the public hall, forcing the door and giving it a dash.
In the event that members are using standpipes located in large warehouse occupancies, it should be noted that many outlets are located a distance from exits. In these cases, members should stretch a utility rope from the exit to the standpipe outlet. This will prevent them from getting lost in blinding smoke should conditions suddenly deteriorate.
Having discussed the tactical use of the standpipe, all that remains is a review of the pump operator's role. Norman suggests the following engine pressures: for a one- to 10-story building, 150 psi for a solid-tip nozzle and 200 psi for a fog nozzle; add 50 psi for each additional 10 stories.
By using a double female and a siamese adapter, a pump operator can pump into a first-floor outlet in the event the fire department connection is inoperative. By familiarizing themselves with the capabilities of the standpipes in their jurisdiction, firefighters can reduce fire losses and life hazards in these high-hazard occupancies.
Lance Peeples has been a firefighter for the city of Webster Grove, MO, for 10 years. He holds a bachelor's degree in public administration and an associate's degree in fire protection technology.