“FIRE STANDPIPE SYSTEMS”

Standpipe Systems

A standpipe system is a fire safety system which is designed to provide rapid access to water in the event that a fire breaks out.

Standpipes are installed as stand-alone systems which act like building specific fire hydrants, providing fire protection which will be readily available to fire fighters.

What is a Standpipe System

History Standpipe systems have been part of our firefighting arsenal for more than 100 years. The basic concept of a standpipe system has not changed extensively since the original NFPA standard was adopted in 1915.

Standpipe System

Systems are used in high-rise buildings, large commercial, retail, and industrial buildings; places of public assembly, and other areas where advancing hoselines would be difficult due to the building size.

Tunnels, such as subways, and shopping malls have a horizontal standpipe system.

Underground buildings, heliports, marinas and boat yards.

Installations Standpipe System

Standpipes are one of the simplest and basic of water delivery systems. Designed to deliver water for manual fire-fighting;

via fixed piping system, will eliminate hose lays, and decrease time to deliver water on the fire.

Standpipe System

Standpipes have several main components;

Water Supplies; municipal or private water mains, gravity tanks, pressure tanks, fire pumps.

Siamese connections, Risers, Cross connections, Valves, Hose outlets.

Standpipe System

Systems are installed in accordance with NFPA 14 “Standard for the Installation of Standpipes and Hose Systems” and any local adopted codes.

Water supply must be established and maintained for 30 minutes.

System and appurtenances are subject to acceptance tests.

All new systems must be tested and approved before allowing building occupancy.

Standpipe System

System is subject to hydrostatic testing; for two hours at 200 psi, or where maximum pressure is 150 psi, tested at 50 psi above highest pressure.

System is subject to a flow test; 2 ½” maximum flow of 250 gpm, 1 ½” maximum flow of 100 gpm. max pressure at any point in thesystem at any time not exceed 350 psi.

Standpipe System

Systems are subjected to additional codes in accordance with;

NFPA 25 “Standard for the Inspection, Testing and Maintenance of Water-Based Fire Protection Systems”.

NFPA 1962 “Standard for the Inspection, Care, and Use of Fire Hose, Couplings, and Nozzles and the Service Testing of Fire Hose”.

Standpipe System

NFPA 22 “Standard for Water Tanks for Private Fire Protection”

NFPA 72 “National Fire Alarm Code”

State and Local codes.

Standpipe System

Types of Standpipe Systems

Types of Systems

There are five types of systems. Basically, they are either “wet” or “dry”.

Automatic wet; water in pipe with a water supply.

Automatic dry; air or nitrogen in pipe with a water supply.

Semi-automatic dry; air in pipe, deluge valve with a water supply.

Manual dry; air in pipe with no water supply.

Manual wet; water in pipe with no water supply.

Note: Combinations systems consist of sprinkler systems interconnected with a standpipe system, most of these systems are “wet”.

Types of Systems

Classes of Systems

Classes of Systems A Class I System –

2 ½” (65 mm) hose connection; used by personnel trained for heavy stream operation, designed to deliver 500 gpm’s at 1st riser and 250 gpm’s at each additional riser, flow to be residual 100 psi at highest hose station, (pre 1993 systems residual 65 psi) bldgs not classified as High-Rise, system can be auto wet, auto dry, manual wet or manual dry, high-rise system must be auto or semi-auto wet except where subject to freezing.

A Class I System - 2 ½” hose connection.

No Hose, designed for FD Use.

No pressure reducing valve present.

Class I Systems

A Class II System –

1 ½” (40mm) hose station; used by building occupants/FD, 100 gpm’s at 100 psi, (65 psi for pre-1993 systems) residual outlet pressure, auto wet system unless subject to freezing, auto dry or semi-auto dry allowed where fire brigade trained to operate w/o FD intervention.

Classes of System

Class II Systems

A Class II System - in the corridor, accessible to the occupants, not more than 100 feet of 1 ½” (40 mm) hose and

30 foot stream, 1” (25.4 mm) hose permitted in light hazard

occupancies, reduced water supply.

Classes of System

Class II Locations

Classes of System

100 feet of hose anda 30 foot stream

Additionalstandpipesrequired

A Class III System –

2 ½” (65 mm) hose connection and a 1 ½” (40 mm) hose station. (features of both Class I and II);

auto wet system unless subject to freezing, auto dry or semi-auto dry allowed where fire brigade trained to operate w/o FD intervention, not more than 100 ft. of 1 ½” (40 mm) hose,

Classes of System

Class III System

Class I and III locations -

Class III system; highest/lowest floor level >30’ of FD vehicle

access, (2010 NYSFC)

Class I system; in every required stairway, (2010 NYSFC)

intermediate floor landing, unless approved by local CEO, (2010 NYSFC)

each side of a horizontal exit, at entrance to grade level passageways, at the roof or highest landing based on slope, any area greater than 150 feet in un-sprinklered or

200 feet sprinklered building.

Classes of System

Horizontal Exit

If more than150 feet un-sprinklered200 sprinklered

If stair goes to the roof andthe roof is 4:12 or less a hose connection on the roof or top landing is required

Located at intermediate landings

Class I location

Classes of System

fire codes now require Class I standpipe hose station outlets at the highest intermediate landing between floor levels in every required exit stairway as the picture illustrates.

Classes of System

A Class III System –

1 ½″ hose connection

2 ½″ hose connection

Horizontal Exit -

The horizontal exit must have a minimum 2-hour fire resistance rating, and the openings in it must be rated at least 1-1/2-hours.

Providing standpipe hose outlets on both sides of the horizontal exit gives firefighters a refuge while fighting a fire on the opposite side of the fire barrier.

Fire Department Connections

Fire Department Connections - allows FD to pump supplemental water for automatic systems and primary water for manual systems, shall be visible and recognizable, located and arranged so that hose lines can be attached without interference, min size of fittings 2 ½” (65 mm) (FCNYS), have a sign with at least 1” letters that read “STANDPIPE”, shall not be less than 18” or more than 48” above grade.

No shut off valves between the FD connection and the system allowed.

Pressure Regulating Devices

Pressure-Regulating Device; a device designed for the purpose of reducing, regulating, controlling, or restricting water pressure, static and residual.

Pressure-Restricting Device; a valve or device designed for the purpose of reducing the downstream water pressure under flowing (residual) conditions only.

Definition of Pressure Devices -

Pressure Regulating Devices

Residual Pressure – pressure acting on a point in the system with a flow being delivered,

where the residual pressure at an 1 ½” (40 mm) outlet on a hose connection exceeds 100 psi (6.9

bar), a pressure regulating device shall be provided to limit the residual pressure at the flow to 100 psi. (6.9 bar)

Pressure Regulating Devices

Static Pressure –

pressure acting on a point in the system with no flow being delivered,

where static pressure at a hose connection exceeds 175 psi (12.1 bar), a pressure regulating device provided to limit static and residual pressure at the outlet of the hose connection to 100 psi (6.9 bar) for 1 ½” (40 mm) hose and 175 psi (12.1 bar) for other hose connections.

Pressure Regulating Devices

Pressure Regulating Devices -

NFPA 14 stipulates the maximum pressure at any point in the system at any time shall not exceed 350 psi. (24 bar) (2413 kPa), critical components in the systems are valves categorized as pressure-regulating devices;

they must be properly set and installed so that proper pressure is maintained at the hose outlet, improperly set valves can result in inadequate streams or an uncontrollable amount of pressure, there are two methods of setting outlet pressure: field set and factory set.

Standpipe Pressure Regulating Valve

Outlet Reducer (restricting device)

Pressure Regulating Valves

Tab restricts how far valve opens

Pressure Regulating Valves, Non-Removable

Tab moved for FD use

Must be bypassed for FD use

Fire extinguisher type pin, remove for FD use

Some may require tools to adjust for greater flow.

Pilot operated valves- Restrict pressure under flow and static conditions

In one survey by a large US city, 75% failed to deliver a fire stream !!

Diaphragm pushes valve closed if inlet pressure rises

Factory set spring sets maximum size of valve opening

Water Supplies

Standpipe System Water Supplies

Acceptable water supplies include; public or private water mains, gravity tanks, fire pumps, and pressure tanks.

Water Supplies

Municipal or Private Water Supply

Gravity Tanks

Fire Pump

Pressure Tank

Public/Private Water Mains

Water Supplies

Water Mains –

most prevalent connection for standpipe system, might supply adequate water for high-rise buildings, might not supply adequate pressure for buildings higher than 10 stories, overcoming the pressure loss in 100’ of height requires 43.3 psi, high-rise buildings often require fire pumps or gravity tanks,

Water Supplies

Gravity Tanks -

Tank materials limited to: steel, wood, concrete, coated fabrics and fiberglass reinforced plastic.

Standard sizes: wood – 5,000 to 100,000 gals, steel – 5,000 to 500,000 gals, factory coated/bolted steel – 4,000 to 500,000 gals, pre-stressed concrete - 10,000 to 1,000,000 gals, reinforced concrete - 10,000 to 500,000 gals.

Water Supplies

Gravity Tanks –

of adequate capacity and elevation make a good primary supply, may be located on top of a building or on a tall tower, water is distributed throughout system by pull of gravity.

Water Supplies

Water Supplies

Gravity Tank

Fire Pumps -

designed to draw water from a supply source, water then pumped into the system under pressure, with a good water supply can pump into system for a long time, sometimes extra pumps are installed in high-rise buildings.

Water Supplies

Fire Pumps –

supply the pressure needed to ensure adequate water volume at efficient pressure, two types of pumps, Automatic and Manual, automatic pump usually arranged with the controller on a pressure drop or waterflow in the standpipe,

Water Supplies

Building fire pumps are designed to produce a limited pressure at the top floor outlets.

Pressure Tanks -

often used where there is enough water but the water pressure is too low, may be used in tall buildings that need extra pressure to supply the highest hoselines, important limitation is the small amount of water that can stored in tanks, tank supply may be used while automatic fire pumps begin to increase supply pressure, may be used as primary or secondary water supply.

Water Supplies

Pressure Tanks -

are enclosed water tanks of limited size, air pressure within the tank provides velocity for discharging water from the tank, normally 2/3 filled with water, charged with a min 75 psi., usually housed in an enclosed heated structure, may be located anywhere in the building or outside the building, max capacity of pressure tanks is typically 9,000 gallons.

Water Supplies

Water Supplies

Sectional View of Pressure

tank

Pressure Hydraulics

Pressure –

pressure is a measure of force acting over an area, measured in terms of “feet of head” or “pounds per square inch”, a column of water 12” high and 1” sq., weighs .434 pounds per sq. inch, no matter what area of the container.

Hydraulics

one cubic foot of water totals 1728 cubic inches, there are 144 sq, inch columns of water in a cubic foot, each weighing .434 lbs, e.g. 144 x .434 = 62,496 lbs, ( onecubic foot = 62.5 lbs., one gallon of water contains 231cubic inches, divide 231 cubic inches into 1728 cubic inches = 7.481 gals in one cubic foot of water.

Hydraulics

if the total weight of a cubic foot of water is 62.5 lbs, divide that by 7.481 gals = 8.35 lbs per gal.

what does all this mean?

delivering 250 gpm to an upper floor of a building through the standpipe system will require lifting more than a ton of water per minute from the street to the fire floor.

Hydraulics

Standpipe Operations

Standpipe Operations

Supplying the system;

through the fire dept connection and/or floor outlets, use 2 ½” or larger diameter hose, when possible, supplied by two different pumpers, when possible, supply two independent FD connections, if building is equipped with a sprinkler and a standpipe, first supply line to feed the standpipe.

Standpipe Operations

Operating from;

bring your standpipe kit, bring 200’ of 2 ½” hose with smooth bore or combination nozzle, DO NOT use constant pressure (automatic type) spray nozzles, many require 100 psi at the nozzle inlet, stretch from the intermediate floor level landing or the floor below the fire floor, flush system before hookup, bleed the nozzle before entry into fire area.

DCC FIRE PROTECTION SYSTEMS

NFPA 14

CLASS OUTLETS PRE-1993 STATS

POST 1993 STATS

1 2 ½500

GPM’s @ 65 psi

residual

500 GPM’s @ 100 psiresidual

2 1 ½60 gpm’s @ 65 psi residual

100GPM’s @ 65 psi residual

3 BOTH 500 GPM @ 65 PSI

500 GPM’s @ 100 psi

PERMITS LONGER HOSE STRETCHES

Standpipe Operations

Standpipe Kit (sample);

metal or plastic tool box or soft-sided bag, an additional controlling nozzle, one 2 ½” - 30ₒ or 45ₒ elbow, one 2 ½” in-line pressure gauge, 2 hose straps, a pair of vise grips, a shove knife, 2 wooden chocks, 2 latch straps, 18 - 20” pipe wrench, 2 operating wheels, a wire brush, a plumbers strap, a 2 ½” adapter, pipe thread to local FD threads, a 2 ½” cap, 2 spanner wrenches.

It Should be Noted

NFPA 14 Standard on standpipe systems went through a reorganization process in 1993, Prior to this change, systems installed pre-1993, only 65 psi (residual) needed to be provided at the most remote floor outlet, but you could expect pressures closer to 40 psi (residual) in older systems, Several high-rise fires with inadequate water pressure contributed to loss of life and large property damage, (One

Meridian Plaza, Philadelphia, PA, First Interstate Bank, Los Angeles, CA)

Expect residual pressures (100 psi or 65 psi) only in a system that operates properly, is well designed and properly maintained.

One Meridian Plaza, February 23, 1991

Summary

Not all communities have high-rise buildings or standpipe systems, but you may be called via mutual aid, Learn about the systems in your response area, Does the system have PRV’s? Re-moveable? Adjustable? Pressure setting? (pre-1993, 65 psi; post-1993, 100 psi) If possible, remove the pressure restricting valve, DO NOT use a constant pressure (auto) type nozzle, DO NOT put your hands in FD connections, DO NOT use the occupant hose unless to save lives.

Prepared by Thomas BartschChief Fire Inspector (ret.)

A special thank you to David K. Walsh, Program Chair,Dutchess Community College Fire Science Programfor his contribution in the preparation of this presentation.