Tactical ventilation - PN 883 Flashcards
Objective here
Define ‘Tactical Ventilation’
Tactical ventilation: The systematic, and coordinated removal of hot smoke and fire gases and their replacement with fresh air as part of the Incident Commander’s (IC) overall incident plan.
Tactical ventilation - PN 883
Define ‘Ventilation’
The removal of products of combustion from a structure and their replacement with a supply of fresher air in order to improve conditions.
Tactical ventilation - PN 883
Define ‘Products of combustion’
Products of combustion consist of flame, heated air, smoke, invisible fire gases and other airborne contaminants.
Tactical ventilation - PN 883
Define ‘Self ventilation/Uncontrolled ventilation’
Self ventilation/Uncontrolled ventilation: Ventilation of a compartment caused by the failure of windows, doors or other elements of structure resulting from the action of the fire.
Tactical ventilation - PN 883
Define ‘Consequential ventilation’
Consequential ventilation: Ventilation of the fire as a result of firefighting operations. When firefighters begin firefighting and rescue operations at a building they cause ventilation as a consequence of their activities. As teams make entry into fire compartments via doors and windows, the ingress of fresh air and the application of water alters the conditions in the compartment. This may lead to rapid fire development and the expansion/spread of the products of combustion beyond the compartment/premises of origin.
Tactical ventilation - PN 883
Define ‘Defensive Ventilation’
Defensive Ventilation: Carried out away from the fire, or after the fire is extinguished, to remove heat and smoke, particularly to improve access and escape routes in areas of the building not directly affected by the fire.
Tactical ventilation - PN 883
Define ‘Offensive Ventilation’
Offensive Ventilation : (See appendix 1: Positive pressure ventilation)
Carried out close to the fire compartment to have a direct effect on the fire itself, to limit fire spread and to make conditions safer for firefighters.
Tactical ventilation - PN 883
Define ‘Natural ventilation’
Natural ventilation: Describes collectively the techniques of ventilation which are not assisted by mechanical means. This includes the use of installed vents, windows and doors.
Tactical ventilation - PN 883
Define ‘Sequential Ventilation’
Sequential Ventilation: (See appendix 1: Positive pressure ventilation)
When multiple floors or rooms are required to be ventilated. The process of sequentially isolating and opening doors and windows so that the area can be cleared of products of combustion.
Tactical ventilation - PN 883
Define ‘Negative pressure ventilation’
Negative pressure ventilation:
Describes the process where ventilation of a compartment is achieved by reducing the pressure within it using fans or a branch set to a cone pattern and directed out of an opening to induce a Venturi effect.
Tactical ventilation - PN 883
Define ‘Positive pressure ventilation (PPV)’
Positive pressure ventilation (PPV): (See appendix 1).
Describes the process whereby fans are used to ventilate a compartment or structure by forcing air into a building. This has the effect of increasing the pressure inside the structure, which drives heat and products of combustion through an outlet to open air.
Note. PPV is currently under evaluation. Two sets of PPV fans are carried on Special All Wheel Drive (SAWD) vehicles. The SAWD vehicles are crewed by operatives who have received specific PPV training. PPV should only be used by appropriately trained personnel.
Tactical ventilation - PN 883
Define ‘Positive pressure ventilation (PPV)’
Positive pressure ventilation (PPV): (See appendix 1).
Describes the process whereby fans are used to ventilate a compartment or structure by forcing air into a building. This has the effect of increasing the pressure inside the structure, which drives heat and products of combustion through an outlet to open air.
Note. PPV is currently under evaluation. Two sets of PPV fans are carried on Special All Wheel Drive (SAWD) vehicles. The SAWD vehicles are crewed by operatives who have received specific PPV training. PPV should only be used by appropriately trained personnel.
