CTE ZED 23.2 JH, Use And Maintenance Manual, Page: 52 / 56

Use and maintenance manual
ZED 23.2 JH
Code n°UM0260_GB
50
9 BEAUFORT WIND SCALE
Force
Type
of wind
at a height of
10 m above
flat
and open ground
Nm/h
Km/h
Description of the effects
on the ground
Description of the effects
at sea
0 calm
0-1
0-1
Calm: smoke rises vertically The sea is like a mirror.
1
light air
1-3
1-5
Direction of wind shown by smoke
drift, but not by wind vanes.
Ripples without crests are formed.
2 light breeze
4-6
6-11
Wind felt on face; leaves rustle;
ordinary vanes moved by wind. Small wavelets. Crests glassy, no
breaking.
3
gentle breeze
7-10
12-19
Leaves and small twigs in constant
motion; wind extends light flag. Large wavelets, crests begin to
break: scattered white caps.
4
moderate breeze
11-16
20-28
Raises dust and loose paper; small
branches are moved. Small waves becoming longer,
numerous whitecaps.
5
fresh breeze
17-21
29-38
Small trees in leaf begin to sway;
crested wavelets form on inland
waters.
Moderate waves taking longer form,
many whitecaps, some spray
6
strong breeze
22-27
39-49
Large branches in motion; whistling
heard in telegraph wires; umbrellas
used with difficulty.
Larger waves start to form
7
near gale
28-33
50-61
Whole trees in motion;
inconvenience felt when walking
against the wind. Sea heaps up: and foam from the
larger waves breaks up and starts
to be blown into streaks.
8
gale
34-40
62-74
Breaks twigs off trees; generally
impedes progress
Moderately high waves with
breaking crests forming spindrift.
Streaks of foam.
9
severe gale
10
storm
11
violent storm
12
hurricane