Fire Officer Tactics: Ventilation (Ch 9) Flashcards
1
Q
2 Reasons for Ventilation
A
- Venting for fire : allows attack teams to enter and operate within the structure
- Venting for life: provides fresh air for breathing and improved visibility while searching.
2
Q
Vertical vs. horizontal ventilation factors
A
- Size and location of the fire
- Construction of the building
- Available staffing
- Effects of weather (wind)
3
Q
PPV considerations
A
- Where is the life hazard (incl. searching FF’s)?
- What is location & extent of fire? Is it in void spaces?
- Status of hose lines? Operating/ready to operate?
- What is degree of fire confinement? PPV may not be necessary if self-vented.
- What exhaust openings are available?
- What PPV equipment is available? Power? Noise at CP?
- Environmental factors (dust, powders, weeds, wind)?
4
Q
Steps to vertical ventilation
A
- Locate proper site (directly over fire)
- Examination holes (kerf, triangle cut)
- Communicate operation to those nearby
- 2 ways off roof
5
Q
Problems with negative pressure ventilation
A
- Fans never fit an opening
- Debris, curtains, other objects drawn against intake screen blocking flow
- Fans in doorways get in the way
- Explosion-proof reliability over time
6
Q
Benefits of PPV
A
- Same job done in half the time
- Clear buildings section by section
- Works well with cold smoke
- Set back from doorways so aren’t in the way as much
- Remove flammable vapors safely.
7
Q
Disadvantages of PPV
A
- Danger of fanning smoldering fire into a serious conflagration
- Problematic in situations involving separate fires in remote areas (arson)
- Can blow fire towards vitims if not used properly
- Requires careful coordination between members
8
Q
Rain roof: definition and problems
A
A roof built over existing roof that has become so porous that it no longer keeps the rain out (Station 13), leaving existing roof in place.
- Added weight not designed into original roof supports.
- Two layers of roof can substantially delay or prevent venting
- Multiple layers create multiple void spaces where fire may hide, which can result in conflicting estimates of fire’s intensity.
9
Q
Additional venting considerations
A
- Never ventilate where it will cause exposure problem
