Card Set Information

2013-10-15 10:45:07

Ventilation questions
Show Answers:

  1. What is ventilation?
    The process of removing smoke, heat, and toxic gases from a burning building and replacing them with cooler, cleaner, more oxygen-rich air.
  2. What are the benefits of proper ventilation?
    • Locate trapped occupants faster
    • Fresh air to occupants
    • Advance hose lines rapidly and safely
    • Reduce backdraft and flashover
    • Limit fire spread
    • Reduce property damage
  3. When performing ventilation, which side of the building is opened first/last?
    Leeward side is always opened first, followed by the windward side.
  4. What are 3 reasons to perform ventilation?
    Life safety, containment, and property conservation
  5. Where should you ventilate?
    As close to the fire as possible
  6. What are the 2 basic types of ventilation?
    Horizontal and vertical
  7. What are the 2 different methods to perform ventilation?
    Natural and mechanical
  8. What are the 3 types of mechanical ventilation?
    Negative-pressure, positive-pressure, and hydraulic
  9. What are the advantages of negative-pressure ventilation?
    Explosion proof motors
  10. What are the limitations of negative-pressure ventilation?
    • Positioning
    • Power source
    • Maintenance
    • Air flow control
  11. What are the advantages of positive-pressure ventilation?
    • Quick and efficient
    • Increased safety
  12. What are the limitations of positive-pressure ventilation?
    • May spread the fire
    • May increase carbon monoxide levels
  13. What 2 things should be kept in mind when performing positive-pressure ventilation?
    • Exit vent hole should be smaller than PPV fan hole
    • PPV fan should cover the entire opening
  14. Describe hydraulic ventilation
    • Fog stream set to cover 90% of the window
    • Nozzle should be roughly 2 feet back from window
    • Advantage is that you can move several thousand cubic feet of air per second
    • Disadvantages are water damage and possible safety hazards
  15. What are 3 types of roof ventilation cuts?
    Rectangular, peak, and trench
  16. Describe a rectangular roof cut
    • Four cuts completely through the decking
    • Use care not to cut structural supports
    • Stand upwind and have a safe exit
    • If several layers exist, you may have to peel a layer at a time
  17. Describe a peak roof cut
    • Used for peak roofs with plywood sheeting
    • A tool is used to reveal the roof covering along the peak
    • A power saw or axe is used to make a series of vertical cuts
  18. Describe a trench cut
    • Used to stop the progress of a large fire in a narrow building
    • Creates large opening ahead of the fire
    • "Writes off" a part of the building
  19. Describe Measures M and when it would be used.
    Measures M is a combination of vertical and horizontal ventilation generally used in a high rise building. 

    • 1) Grade level exterior door is opened.
    • 2) Grade level stairwell door is opened.
    • 3) Fire floor stairwell door is opened.
    • 4) Fire unit door is opened.
    • 5) Fire unit doors/windows are opened.

    Positive pressure fan is placed in front of the exterior door and forces out all the smoke and toxic gases created in a fire.