“Hose stream demand” is
the amount of water that must be added to the sprinkler sys- tem hydraulic calculations
so there is adequate supply to operate the sprinklers for effec- tive fire control, and fill the hoses for fire extinguishment.
What is a hose stream?
The hose stream test was developed in the late 1890s to
measure the structural integrity of floor materials and cast or wrought iron in building walls during an intense fire
. It was not intended or designed to test the thermal stress performance of glazing materials.
What is the hose stream allowance?
Accounting for hose stream allowances. Sprinkler hydraulic calculations are
required to account for the water used by the fire department to manually suppress a fire
. This is referred to as a hose stream allowance.
How do you calculate sprinkler water demand?
SPRINKLER SYSTEM DEMAND
Theoretically, sprinkler demand is
equal to density (gpm/ft*) multiplied by the demand area (ft’)
. Density. This is the amount of water applied by the sprinklers per square foot over the demand area per minute.
What does NFPA 13 mean?
NFPA 13 is
an installation standard
and does not specify which buildings or structures require a sprinkler system. NFPA 13 specifies how to properly design and install a sprinkler system using the proper components and materials after it has been determined that a sprinkler system is required.
How are hose demands accounted for in sprinkler system calculations?
When the sprinkler system has two or more small hose stations attached to it,
the designer must add 100 gpm to the water supply requirement
for the sprinkler system. … The flow values must be added into the calculations where the hose stations are connected to the sprinkler system.
What are the three techniques used to fight fires?
- Direct Attack Technique. This must be the most well-known technique for firefighting. …
- Indirect Attack Technique. …
- The Combination Attack Technique. …
- Fog Attack Technique. …
- The “Two Lines In” Technique.
Which is a characteristic of smooth bore nozzles?
Smooth bore nozzles also use
the lowest engine pump pressures, allowing for maximum reach
. Smooth bore nozzles are often referred to as solid bore nozzles because they produce a solid stream to provide maximum reach and penetration to the seat of the fire.
How much PSI does a sprinkler need?
Water pressure is measured in pounds per square inch – also called psi. The average water pressure for most homes and businesses is between 30 psi and 50 psi; most sprinkler systems are designed to use pressures of
around 30 psi
.
How many sprinkler heads can you put on one line?
At different pressures, the sprinkler head and nozzle will consume different amounts of water. For example, at 35 pounds per square inch (PSI) the 5000 Series Rotor using the 3.0 nozzle will use 3.11 gallons per minute (GPM). If your home’s water capacity was 10 GPM, you could place
3 heads per zone
.
How much pressure is in a fire hydrant?
Fire hydrants are flow-tested at a residual pressure
of 20 psi
; therefore, firefighters should understand the typical flow rates of fire hydrants at that pressure.
What is the latest NFPA 13?
The
2022 edition
of NFPA 13, Standard for the Installation of Sprinkler Systems, is the transformative next step for designers, engineers, contractors, and installers involved with water-based fire protection in today’s world.
Is NFPA required?
In most cases,
compliance with NFPA standards is voluntary
. However, in some cases, federal or state Occupational Safety and Health (OSHA) agencies have incorporated wording from NFPA standards into regulations. In these cases, complying with the standards is mandatory.
What does NFPA 72 stand for?
NFPA 72,
National Fire Alarm and Signaling Code
covers the requirements for installation performance of fire alarm systems. 3. … NFPA 101, Life Safety Code and other codes determine whether occupant notification is required in a given occupancy.
How do you calculate hydraulics?
For instance the calculation of power output. Hydraulic power is defined as flow multiplied by pressure. The hydraulic power supplied by a pump is:
Power = (P x Q) ÷ 500
– where power is in kilowatts [kW], P is the pressure in bars, and Q is the flow in litres per minute.
Why are return bends needed for pendent sprinkler heads on a wet system?
The purpose of a return bend, also known as gooseneck, is
to prevent the accumulation of sediment, mineral deposits, and pipe scale in the pipe drop to a fire sprinkler
. If these materials collect, the drop pipe or sprinkler orifice could be obstructed and impaired.
