CH. 17 Positioning Aerial Apparatus Flashcards
Aerial: Standard Operating Procedures for Positioning
- Different procedures for positioning aerial apparatus assigned to initial response include these 3 examples:
1) When two aerials respond to a given location, first arriving takes the front of building and second goes to rear or side of building
2) When two aerials respond to given location, first aerial position is based on the present conditions, second aerial stages one block away
3) When a single aerial responds, the apparatus takes a strategically sound location in front of the fire building unless otherwise directed. Apparatus may be centered in front of building for offensive operations or at corner for defensive - Building less than 5 stories (60 feet) aerial parked on outside
Tactical Considerations Affecting Aerial Apparatus Position
-Proper distance between objective and the aerial is the distance that affords maximum stability, best climbing angle, and adequate extension
-Long extensions at low angles place the maximum stress on aerial and can reduce its load-carrying capacity
-Stress is greater when aerial device is in motion
-Do not park in collapse zone if building exposed to severe fire (1 ½ time building height)
Spotting the Aerial Apparatus:
Surface Conditions
- Consider when spotting aerial ladder
- Last alternative should apparatus be parked on soft surface
- thin-skinned paved surfaces may be punctured causing truck to sink and possibly tip
- Stabilizer pads provide better weight distribution
-used whenever the stabilizers are used - Vaulted Surfaces- voidspace underneath
-manhole covers are good indicator of underground voids - Hot Surfaces:
-Extreme heat may weaken paved surfaces
-Indicator when asphalt “Bleeds” shiny, glass-like surface
Spotting the Aerial Apparatus:
Grade
- Position with the front of apparatus uphill
-Rear tires off ground truck has less chance of sliding
-Rear compartments will be difficult to reach
-preferred when only equipped w/ rear stabilizers - Position with rear of apparatus uphill
-Easier to reach ground with rear-mounted turntable
-Front tires will be lifted off ground
-By facing uphill angle of turntable is decreased
Spotting the Aerial Apparatus:
Windy Conditions
-impose dynamic load on aerial device
-May reduce overall stability
-Position device preferably parallel to wind direction
-spot to minimize the extension needed when possible
Spotting the Aerial Apparatus:
Electrical Hazards
- “Look up and Live”- always check operating vacinity for powerlines before you drive into it
- Long standing fire service standard:
-Provide 10 feet clearance of 600 to 50,000 volts
-Provide 50 feet clearance of lines greater than 50,000 volts - OSHA’s revised standard:
-20 ft clearance for lines less than 350 kilovolts
-50 ft for lines over 350 kilovolts
Spotting the Aerial Apparatus:
Angle and Location of Aerial Device
-Stability can be improved by operating the aerial device in line with longitudinal axis (apparatus body)
-Most stable when device is operated directly over front or rear of vehicle
-Rear-mounted aerial device, backing in the apparatus is preferred method and maximizes the reach of aerial device
Spotting the Aerial Apparatus:
Jackkniffing Tillers
- turning the tractor at an angle from the trailer
- increase stability
-Greatest stability angle is approximately 60-degree from in-line w/ aerial device extended away from this angle
-Good stability occurs at angles up to 90-degrees
Spotting the Aerial Apparatus:
Stress on Aerial Device
- Stress- Factors that work against aerial device strength
- May be imposed in static and dynamic operation
-Stress is greater when aerial is in motion - When approaching from the uphill side, park past the building and operate from rear
- When approaching from downhill side, stop short of building and operate over cab
- Ideally the truck should be operated in uphill position with the aerial device directly in-line to reduce the stress
Aerial Device: Supported/Unsupported Positions
- Device may be designed for one or the other
- Unsupported at the tip (cantilever)
-Maximum load occurs when operated at angles between 70 to 80 - Supported (resting on wall) low angels of elevation during unsupported operations
- Operating at low angle of elevation and long extension are at their weakest
Approaching, Positioning, and Operating at Highways
-Never drive against traffic unless cleared by DLE
-Position at angle to act as shield
-Turn front wheels away from firefighters working highway
-Close at least one lane next to incident
-Park 150 to 200 feet back
-no highbeams
-minimal warning lights
Approaching, Positioning, and Operating at Railroads
-Treat as active
-Keep at least 25 feet from tracks
-Park on same side of tracks as incident
Approaching, Positioning, and Operating at EMS Incidents
-Give rescue best position for patient loading
-Park between smaller apparatus to block traffic
Approaching, Positioning, and Operating at HAZMAT Incidents
-Obtain wind speed and direction
-Approach upwind and uphill
-Stop well short of incident
-Potential exposures of high levels of heat
Approaching, Positioning, and Operating at Aircraft Incidents
Used For:
Aerial Device used to provide access for:
- Shuttle equipment and personnel from aerial apparatus to work area
- Primary used to transport firefighters and equipment
- Passenger Rescue:
-If tip is to be placed in doorway, the apparatus should position for accessing the window of a building
-If the objective is to provide access over a wing or remove victims from a wing, positioning principles are basically the same as for providing access to the roof of a building
- Ventilation
- Deploying handlines to interior
- Master Streams
