Firefighter Pre-Basic VII

The student will demonstrate a basic understanding of forcible entry tools and techniques by applying the material in a practical setting. Session Reference: 7 Topic: Firefighter Pre-Basic VII Level of Instruction: Time Required: 3...


• Window crank usually light

• Window lock located in middle or bottom of window

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• Best way to open window is break out pane of glass, reach in and unlock window, and force it open with pry tool

• If heat not intense, remove second pane to operate crank

• Many casement windows too narrow to allow entry

• Narrow windows often located at sides of large glass picture window

 

III. INTRODUCTION TO VENTILATION (7-3)

Ventilation Techniques and Theory

• Hot air rises using the path of least resistance and spreads or mushrooms out and downward

• Natural ventilation utilizes existing opening such as windows and roof openings

• Mechanical ventilation utilizes smoke ejectors or blowers

• Hydraulic ventilation utilizes nozzles and water flow air currents

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Importance and Timing of Ventilation

• Coordinate with fire attack since the increase in air flow will accelerate burning

• Ventilation removes smoke and heat and increases visibility

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Ventilation Equipment

• Smoke ejector - electric or gas-powered fan designed to exhaust smoke or blow in fresh air; air blows over motor; generally placed high in opening to exhaust smoke or low in opening to introduce fresh air

• Blower - electric or gas-powered fan designed to force air into an area at high velocity; placed six to ten feet from opening with air cone covering as much of the opening as possible

• Nozzle - nozzle is positioned two to three feet from opening with stream covering as much of opening as possible (at least 90%)

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Backdraft

• A condition where there is insufficient air to support combustion

• A sudden introduction of fresh into an oxygen-starved fire causes a backdraft explosion

• Signs of backdraft include puffing smoke going in and out of the building, dark smoke in the structure with little flame, smoke emitting from openings in building

• Backdraft is relieved by venting at the highest point in the structure

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Roof Construction

• Shingle - consists of plywood sheathing on roof trusses, tar paper, and asphalt shingles

• Composition - consists of wood or metal sheathing covered with felt material; tar and gravel provides water resistance

 

IV. VENTILATION TECHNIQUES (7-4)

Windows

• When time permits, windows should be opened

• Double hung windows should be opened two-thirds down from the top and one-third up from the bottom

• Open other types of windows as much as possible

• Storm windows must also be opened or removed

• Shades, blinds, drapes, curtains, and other window coverings must be moved away or removed

• When wind is a factor, windows on leeward side should be opened first

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• Window and roof ventilation

• When roof or roof features must be opened for venting, windows on top floor should be opened

• If windows on several floors must be opened, begin on top and work down

• Opening windows from below first may cause fire and smoke spread

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Natural Roof Openings

• In multi-story buildings, vertical shafts carry stairways, elevators, dumbwaiters, electric wiring, heating ducts, and plumbing and sewer pipes

• Shafts extend full height of building

• Convected heat, smoke, and gases will rise within and around shafts

• If shafts are not vented at top, fire will travel horizontally

• Pressure will force heat, smoke, and gases throughout upper part of building

• Shafts are capped at roof with various closures (make sure of area being vented when cap is removed)

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Cutting Through Roofs

• At times, only way to properly ventilate is cut hole in roof

• Roof made of boards can be cut with axe

• Roof made of plywood should be cut with power saw

• Care should be taken not to cut joists or other structural members

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• Single large hole is more effective than several small holes