Salvage, Overhaul and Ventilation

Question 1

Define salvage, as applied to fire fighting:

Answer 1

Salvage is the prevention or reduction of damage from indirect causes, such as heat, smoke, water, falling debris, breakage and dust.

Question 2

List the three (3) phases of salvage and state when each phase is carried out:

Answer 2

1. Preventative - Takes place simultaneously with firefighting to reduce the amount of avoidable damage.
2. Protective - Covers those activities that are undertaken in conjunction with the control of the fire. It is a natural extension of preventative salvage and should be extended as crews become available
3. Recovery - Commences once the fire has been extinguished and includes removing hoses, remaining water, moving items back to original locations and covering damaged roofs.

Question 3

List five (5) pieces of equipment carried by your agency that can be utilised in salvage work:

Answer 3

• Tarps
• Brooms
• Fan
• Ladder
• Charged hose line

Question 4

Detail three (3) uses for salvage tarpaulins:

Answer 4

• Covering damaged roofs and protecting from the weather.
• Covering items that need to be protected from water, heat and smoke
• Re-directing water from confined spaces by rolling into tubes

Question 5

List five (5) reasons why you would ventilate a structure:

Answer 5

• Improve the safety of people trapped in the building.
• Reduce damage to the structure and its contents from heat and smoke.
• Provide exposure protection to uninvolved areas or adjoining structures.
• Prevent or reduce the spread of fire due to build-up of heat i.e. backdraught, flash over
• Improve firefighting conditions by: - increasing visibility in the structure, providing a non-toxic atmosphere, reducing temperature inside the structure.

Question 6

List four (4) types of ventilation and briefly describe each one :

Answer 6

Natural

Opening windows and doors to use natural air currents to ventilate the space

Manual

Vertical ventilation - making of openings above the fire, usually at roof level

Horizontal ventilation - creating openings at about the same level as the fire

Mechanical

Using a fan to draw out combustion products by negative pressure, or driving large quantities of fresh air into a building, and force out heated gases and smoke by positive pressure.

Hydraulic

Using a wide spray pattern (fog) on hose lines, air is drawn into the fog stream and products of combustion are drawn to the outside of the building .

Question 7

List six (6) benefits of overhaul:

Answer 7

• Locates ‘hidden’ fires
• Prevents rekindling of the fire
• Helps determine the cause of the fire
• Aids in recognising and preserving evidence of arson or other crimes
• Prevents unnecessary damage.
• Improves public relations.

Question 8

List eight (8) advantages of positive pressure ventilation:

Answer 8

• Firefighters can set up positive-pressure ventilation procedures without entering the smoke-filled environment
• Allows more efficient removal of smoke and heat from the structure or vessel.
• Velocity of air currents within the building are minimal and have little, if any, effect that disturbs the building contents or smouldering debris.
• Total exchange of air within the building is faster than using negative-pressure ventilation.
• Placement of fans does not interfere significantly with ingress or egress.
• Particularly effective at removing smoke from large, high ceiling areas where negative-pressure ventilation is ineffective.
• Heat and smoke may be directed away from unburned areas or paths of exit.
• Can be initiated much quicker, with fewer personnel.