Ch6 pg 143-148 standpipe

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of a simple orifice plate in firefighting hoses?

To eliminate the need for a nozzle at the end of the hose

To create friction loss and reduce downstream flowing pressure (correct)

To completely stop the flow of water through the hose

To increase static pressure within the hoseline

In what condition will pressures build up within the hoseline when using a pressure-restricting device?

When the nozzle is partially open

When the nozzle is shut (correct)

When the nozzle is fully open

When the outlet valve is closed

What precaution should be taken before connecting a fire department hose to a standpipe outlet?

Remove all surrounding water sources

Make sure the hose is longer than 100 feet

Probe inside the threads to check for obstructions (correct)

Ensure the outlet valve is fully open

How does a vane-type pressure-restricting valve (PRV) control water flow?

By using a movable plate with overlapping holes to adjust flow Signup and view all the answers

What role does the member who controls the outlet valve play during firefighting operations?

They maintain communication with the nozzle team to coordinate pressures Signup and view all the answers

What is a primary concern when untrained building occupants attempt to use a hose during a fire?

They may inadvertently increase the danger in the stairwell. Signup and view all the answers

Why is limiting the pressure at hose outlets to a maximum of 80 psi necessary for untrained users?

To protect them from injuries due to excessive pressure. Signup and view all the answers

What is a requirement for Class III systems regarding the 21/2-in outlet post-1993?

They permit pressure up to a maximum of 175 psi. Signup and view all the answers

How should a firefighter assess the safety of opening the stairway door during an emergency?

They must evaluate the potential risk to stairwell occupants before opening. Signup and view all the answers

What is an outcome of having trained personnel nearby when untrained occupants use the hose?

Lower risk of occupant injury or damage. Signup and view all the answers

What is the primary purpose of Class II fire systems?

To control minor fires until the fire department arrives Signup and view all the answers

Which feature distinguishes Class III standpipe systems from Class II systems?

The integration of heavier hose streams for fire department use Signup and view all the answers

Why should fire departments not rely on building hoses for attack lines?

They may often be missing or damaged and untested Signup and view all the answers

What is a potential issue with the NFPA's recommendation regarding the placement of hoses in Class III systems?

It may lead to a charged line filling the stairway with smoke during evacuation Signup and view all the answers

In which type of occupancy are Class II systems frequently permitted?

Fully sprinklered buildings and low-hazard occupancies Signup and view all the answers

What primary limitation do pressure-reducing valves (PRVs) present during a fire emergency?

They are often set at a pressure too low to provide effective fire streams. Signup and view all the answers

Why should the use of certain PRVs be discouraged in favor of more reliable options?

They require frequent adjustments and can be prone to failure. Signup and view all the answers

What action must be taken to bypass a combination outlet control and pressure-reducing valve for fire department use?

Remove a pin similar to that of a fire extinguisher. Signup and view all the answers

What percentage of PRVs failed to provide an effective fire stream during a survey in a major metropolitan city?

75% Signup and view all the answers

How often should the maintenance and flow testing for PRVs be conducted for optimal performance?

At least every year Signup and view all the answers

What is a critical consideration when controlling the standpipe outlet valve?

Using a gauge to monitor pressure accurately Signup and view all the answers

What should be done before connecting a hoseline to a standpipe system?

Visually inspect or crack open the valve discharge opening. Signup and view all the answers

Why is it important to inspect the standpipe outlet valve?

To prevent the release of stowed items into the hoseline. Signup and view all the answers

What should the member at the nozzle do in relation to the standpipe outlet valve?

Monitor and relay pressure requirements to the valve controller. Signup and view all the answers

What can happen if items are stashed inside the standpipe outlet valve?

They will likely be forced through the hoseline when charged. Signup and view all the answers

When should the first hoseline not be stretched from the standpipe in a standpipe-equipped building?

When the fire is on the ground floor. Signup and view all the answers

What is typically faster when fighting a fire in a standpipe-equipped building?

Using preconnected lines off the apparatus. Signup and view all the answers

What should be evaluated in relation to a fire before deciding on the hoseline stretch?

The location of the fire in relation to access. Signup and view all the answers

In which scenario might it be advantageous to stretch a hoseline from the apparatus rather than the standpipe?

When fighting a ground floor fire. Signup and view all the answers

Which factor does NOT influence the decision to use a standpipe for a hoseline stretch?

The firefighter's familiarity with the building. Signup and view all the answers

What is primarily saved by using a standpipe system in high-rise firefighting?

Time Signup and view all the answers

What must be verified first before using a standpipe for firefighting?

The location of the fire Signup and view all the answers

Why might an attack team prefer to use the nearest staircase to the fire?

To minimize their exposure to smoke Signup and view all the answers

In large buildings, what is a potential disadvantage of multiple staircases with standpipe risers?

Confusion in hose routing Signup and view all the answers

What is a key consideration for the attack crew when deciding to use a standpipe?

The height of the fire's location Signup and view all the answers

What is the main challenge when responding to fires in standpipe-equipped buildings?

Identifying the fire's location Signup and view all the answers

What is the minimum height for a building to require a standpipe system?

75 ft Signup and view all the answers

Why might firefighters be delayed in their response to a standpipe building?

Incorrect assumptions about building size Signup and view all the answers

How does the 'reflex time' impact firefighting operations?

It lengthens the time until firefighters can engage the fire. Signup and view all the answers

What crucial preparation should be done in advance concerning large buildings?

Identification of standpipe-equipped buildings Signup and view all the answers

Which factor contributes to the potential fire area in non-sprinklered large buildings?

Size of the building Signup and view all the answers

What is a potential misconception about large buildings when responding to a fire?

They always have sprinkler systems. Signup and view all the answers

How does a firefighter's preparation differ when dealing with a standpipe-equipped building?

They need to consider standpipe operation strategies. Signup and view all the answers

What is the main reason for the attack crew to select the riser closest to the seat of the fire?

To ensure that the line will reach the fire Signup and view all the answers

Before 1993, which was the maximum distance a hose could effectively reach based on NFPA regulations?

30 feet stream reach and 100ft of hose from the nearest stand-pipe Signup and view all the answers

In a multi-riser building, how many lengths of hose would theoretically suffice to reach any fire from the nearest outlet?

Two lengths of hose Signup and view all the answers

What impact does having a 100-foot hose line have on the hose stream's reach?

It increases accessibility from far locations Signup and view all the answers

Why is it essential for the attack crew to know the layout of multi-riser buildings?

To quickly select the nearest riser for effective reach Signup and view all the answers

What is the main change post-1993 to the NFPA 14 regarding hose length requirements for reaching fire floors?

Increasing the maximum distance to 200 ft plus the height of the stair landing. Signup and view all the answers

Why was the distance from the hoseline reduced in New York City’s fire code?

To account for lower operating pressures commonly encountered at first. Signup and view all the answers

What was a significant consequence of revisions made to the NFPA 14 after the Philadelphia incident?

Requirements for hose length actually increased to accommodate safety. Signup and view all the answers

How many lengths of hose are minimally required to reach the most remote areas in a nonsprinklered building according to post-1993 NFPA 14?

Four 50 ft lengths. Signup and view all the answers

What is a concern regarding the implementation of maximum distance limitations in standpipe systems?

They allow for potentially hazardous locations for standpipe outlets. Signup and view all the answers

What was the maximum distance of reach allowed for a hoseline in the pre-1993 version of NFPA 14?

100 ft. Signup and view all the answers

Which factor has NOT been cited as influencing the amount of hose required on the fire floor?

The type of fire equipment used. Signup and view all the answers

What requirement was introduced for standpipe outlets in nonsprinklered buildings after the revisions to NFPA 14?

They should be located at half landings between floors. Signup and view all the answers

Study Notes

Class II Fire Systems

Class II systems are intended for occupant use to manage small fires prior to fire department arrival.
Equipped with 1½-inch hoses and open or fog nozzles, with design flow typically at 100 gallons per minute (gpm).
Not suitable for serious interior fires due to potential damage and wear; fire departments do not rely on these hoses for attack lines.
Commonly permitted in fully sprinklered buildings and low-hazard occupancies under the assumption they can extinguish small fires.

Class III Standpipe Systems

Designed for both heavy hose streams for fire department use and first-aid hoses for occupants.
Features include separate valves for 2½-inch and 1½-inch outlets, commonly utilizing a reducer on the 2½-inch valve.
NFPA recommends that occupant-use hoses be located outside stairwells to avoid smoke buildup during evacuations.
Firefighters must evaluate the impact of opening stairway doors on overall occupant safety in the event of a fire.

Pressure Reducing Valves (PRVs)

Control and restrict outlet pressure to protect untrained users from excessive pressures; typically limited to a maximum of 80 psi (100 psi post-1993).
Various devices include orifice plates and vane-type PRVs that manage flow and pressure through mechanical means.
PRVs may experience failures; during a past incident, over 75% failed to provide effective fire streams highlighting the need for regular maintenance and testing.

Standpipe Operations

Standpipe systems are essential in larger buildings, typically required by code for structures over 75 feet high or 20,000 sq ft per floor.
Responding to fires in these buildings presents challenges, including locating the fire and efficiently venting smoke.
Firefighters must be pre-planned for operations including determining the location of standpipes and potential hose stretches.

Fire Location Considerations

The first hoseline may not always be stretched from the standpipe; the decision depends on the fire’s location and accessibility.
Above the second floor, the standpipe is generally preferred due to time efficiency and reduced friction loss.
Effective fire operations require verifying the fire's location and ensuring the selected standpipe can reach it.

Post-1993 NFPA 14 Modifications

Post-1993 revisions expanded the required hose reach from a standpipe to ensure adequate firefighting capabilities, allowing for greater distances than before.
The new requirements mandate a minimum clear reach from the outlet, with increases in the length of necessary hoses for efficiency.
Challenges persist with code provisions that may lead to standpipe placement outside protected areas, impacting response effectiveness.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the key features and differences between Class II and Class III fire systems. Learn about their design, intended use, and safety considerations for occupants and firefighters. Assess your understanding of fire management systems in various building scenarios.