Flow Path and Vent

Question 1

Define Flow Path

Answer 1

The movement of smoke, heat, gases and flames from high pressure areas within the fire area to available low pressure areas.

Question 2

Define Ventilation

Answer 2

The process of removing heat, smoke and gases from the effected building in order to improve visibility and air quality for FFs and occupants.

Question 3

Unidirectional flow

Answer 3

Flow through an opening in one direction, occurs with multiple openings.

Question 4

Bidirectional flow

Answer 4

Flow in 2 directions thorugh an opening, occurs with a single opening.

Question 5

What do you look for while reading smoke?

Answer 5

Volume
Velocity
Density
Colour

Density is most important

Question 6

Define neutral plane

Answer 6

The break between smoke and fresh air in fire compartment.

Question 7

Ventilation

Answer 7

Ventilation, as applied to FFing, is the PLANNED, SYSTEMATIC AND frequently used to release heated air, smoke and toxic gases from a confined space and the replacement with cooler fresh air.

Question 8

Gas powered PPV’s, size and place?

Answer 8

20” and on ladders

Question 9

Electric PPV, size and place

Answer 9

20” on pumps, twist lock w junction box

Question 10

gas electric PPV

Answer 10

16” on rescue

Question 11

What is mushrooming?

Answer 11

Mushrooming is the lateral and downward migration of smoke when it encounters a
physical barrier.

Question 12

Three disadvantages of forced ventilation are listed below:

Answer 12

a. It can “feed” the fire with fresh oxygen.
b. It requires a power source.
c. It requires special equipment.

Question 13

Five advantages of forced ventilation are listed below:

Answer 13

a. It is controllable.
b. It can supplement natural ventilation.
c. It is faster than natural ventilation.
d. It reduces smoke damage.
e. It aids in property conservation.

Question 14

Four limitations of horizontal ventilation are listed below:

Answer 14

a. Horizontal ventilation will send the smoke, gases, or heat into the same
corridors that fire fighters and building occupants are using. Rescue
considerations come first.
b. Remember that hot gases rise during ventilation and may ignite
neighboring structures. Make sure charged hose lines are in place before
horizontal ventilation is started - unless the building must be opened to
begin rescue operations.
c. Do not ventilate the windward side of a structure before opening the
leeward side; you may disturb the delicate balance of thermal layers.
d. Do not obstruct the ventilation opening. Remember, air can’t get through
an obstruction, keep low and out of the natural ventilation flow path.