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IT EN DA
648941 IT-EN-DA (26/04/2016)
IT EN DA
Ensure that the wind speed is not higher than 36 km/h - 10 m/s (22.3 mph - 32.8 ft/s).
To visually recognise this wind speed, refer to the empirical wind evaluation scale below:
BEAUFORT scale (wind speed at a height of 10 m on a at site)
Force Type of wind
Speed
(knots)
Speed
(km/h)
Speed
(m/s)
Eects on Land Sea conditions
0
Calm 0 - 1 0 - 1 < 0,3
Smoke rises vertically. Sea is like a mirror.
1
Light air 1 - 3 1 - 5 0,3 - 1,5
Smoke indicates direction of wind.
Ripples with appearance of scale, no
foam crests.
2
Light breeze 4 - 6 6 - 11 1,6 - 3,3
Wind felt on face, leaves rustle. Short wavelets, but pronounced.
3
Gentle breeze 7 - 10 12 - 19 3,4 - 5,4
Leaves and small twigs in constant motion.
Very small waves, crests begin to
break.
4
Moderate
breeze
11 - 16 20 - 28 5,5 - 7,9
Wind raises dust and loose pieces of paper;
small branches are moved.
Small waves, becoming longer,
numerous whitecaps.
5
Fresh breeze 17 - 21 29 - 38 8 - 10,7
Small tees in leaf begin to sway.
Wavelets form on inland waters;
moderate waves, taking longer
form.
6
Strong breeze 22 - 27 39 - 49 10,8 - 13,8
Large branches in motion, whistling heard
in overhead wires, umbrella use becomes
dicult.
Larger waves forming, whitecaps
everywhere, some spray.
7
Near gale 28 - 33 50 - 61 13,9 - 17,1
Whole trees in motion, inconvenience felt
when walking against the wind.
Sea heaps up; white foam from
breaking waves begins to be blown
in streaks along the direction of the
wind.
8
Gale 34 - 40 62 - 74 17,2 - 20,7
Wind breaks twigs o trees; impedes
progress.
Moderately high waves of greater
length; edges of crests begin to
break into spindrift.
9
Strong gale 41 - 47 75 - 88 20,8 - 24,4
Wind damages roofs (chimneys, slates,
etc.).
High waves, crests of waves begin
to topple, streaks of foam; reduced
visibility.
10
Storm 48 - 55 89 - 102 24,5 - 28,4
Seldom experienced inland; trees upro-
oted; considerable structural damage
occurs.
Very high waves; white streaks of
foam; reduced visibility.
11
Violent storm 56 - 63 103 - 117 28,5 - 32,6
Very rare, widespread damage.
Exceptionally high waves able to
hide medium sized ships from view,
reduced visibility.
12
Hurricane 64 + 118 + 32,7 +
Devastating damage.
Sea completely white; air lled
with foam and spray, very reduced
visibility.