SAFETY
1-24 / Mid-Mount Ascendant Aerial Tower
© 2021 Pierce Manufacturing Inc. All Rights Reserved.
1-10.14c Ice Build-up Limit
With any amount of ice beginning to form on your device you must use the “Ice Conditions” load chart found in this
manual. The ice rating of your device assumes that no portion of the aerial device has more than 0.25 inches (6 mm)
of ice built up on it. If any portion of the aerial device is covered with more than this depth of ice, the device must be
removed from service until the ice can be removed. Pay special attention to the higher portions of your device as
ice load will have greater impact on stability the higher up it accumulates on the device.
1-10.15 Aerial Operation in High Winds
High winds can tip over any aerial device. Study your aerial device load chart to determine what wind speed your
device's design has accounted for, and in what wind conditions you can safely operate. You must then select a
method that you will use to determine the wind speed while you are operating. Possible methods include:
•
A wind speed indicator mounted at the tip of the device (available as an option on your apparatus).
•
A wind speed indicator mounted on a light tower or other extendable device on another apparatus at the scene.
•
Local weather reporting from a reliable nearby source.
Wind speeds usually increase the higher up you climb, and the wind speed at the tip of the device will have the
greatest over-turning impact. Retract and stow your device before the wind conditions increase above your device's
safe limit.
Never operate in wind conditions that exceed the wind rating on the load chart.
Table 1-1: Beaufort Scale (For Reference Only)
1-10.16 Aerial Device Wire Rope Cable
A pinch hazard may exist wherever wire rope cables contact other mechanical parts such as hydraulic cylinders,
pulleys, sheaves, roller guides, or features on the load. Wire rope cables under tension are a source of stored
energy. If they break, they can injure or kill.
Follow these safe practices during aerial operation:
•
Always stay clear of wire rope during operation.
•
Never touch wire rope while in tension or under load.
•
Never touch wire rope while someone else is at the controls or during operation.
•
Never operate a device that has damaged wire rope.
•
Keep cutting tools clear of wire rope.
Beaufort
Number
Wind Speed
(mph)
Description
Land Conditions
0
0
Calm
Calm. Smoke rises vertically.
1
1-3
Light Air
Wind motion visible in smoke.
2
4-7
Light Breeze
Wind felt on exposed skin. Leaves rustle.
3
8-12
Gentle Breeze
Leaves and smaller twigs in constant motion.
4
13-18
Moderate Breeze
Dust and loose paper raised. Small branches begin to move.
5
19-24
Fresh Breeze
Smaller trees sway.
6
25-31
Strong Breeze
Large branches in motion. Flags waving near horizontal. Umbrella
use becomes difficult.
7
32-38
Near Gale/Moderate Gale
Whole trees in motion. Effort needed to walk against the wind.
8
39-46
Fresh Gale
Twigs broken from trees. Cars veer on road.
9
47-54
Strong Gale
Light structure damage.