Swim in a glassy flat lake on an early morning and the decibel level is quite low. That is, your swim is silent with the simple entry of your hands in the water and the soft beating of your kick. Quiet and tranquil, peaceful and placid.

But swim in a bumpy sea with whitecaps and the winds howling – and the decibel level increases dramatically. You can hear your laborious efforts as you pierce the waves and slam over the top of whitecaps. The slam of your arms against the swells and the rush of the turbulence against your ears is relentless.

While the Beaufort Scale is an empirical measure for describing wind speed based mainly on observed sea conditions, the decibel comparison chart helps you understand the volume levels of various sources and how they can affect our hearing.
equivalent to Beaufort 12. However, the extended Beaufort numbers above 13 do not match the Saffir-Simpson Scale. Category 1 tornadoes on the Fujita and TORRO scales also begin roughly at the end of level 12 of the Beaufort scale but are indeed independent scales.

0 – Flat. Calm. Smoke rises vertically. < 0.3 m/s wind speed
1 Light air 1.1–5.5 km/h 0–0.2 m Ripples without crests. Smoke drift indicates wind direction and wind vanes cease moving. Beaufort scale 1.jpg
1–3 mph
1–2 kn 0–1 ft
0.3–1.5 m/s
2 Light breeze 5.6–11 km/h 0.2–0.5 m Small wavelets. Crests of glassy appearance, not breaking Wind felt on exposed skin. Leaves rustle and wind vanes begin to move. Beaufort scale 2.jpg
4–7 mph
3–6 kn 1–2 ft
1.6–3.4 m/s
3 Gentle breeze 12–19 km/h 0.5–1 m Large wavelets. Crests begin to break; scattered whitecaps Leaves and small twigs constantly moving, light flags extended. Beaufort scale 3.jpg
8–12 mph
7–10 kn 2–3.5 ft
3.4–5.4 m/s
4 Moderate breeze 20–28 km/h 1–2 m Small waves with breaking crests. Fairly frequent whitecaps. Dust and loose paper raised. Small branches begin to move. Beaufort scale 4.jpg
13–17 mph
11–15 kn 3.5–6 ft
5.5–7.9 m/s
5 Fresh breeze 29–38 km/h 2–3 m Moderate waves of some length. Many whitecaps. Small amounts of spray. Branches of a moderate size move. Small trees in leaf begin to sway. Beaufort scale 5.jpg
18–24 mph
16–20 kn 6–9 ft
8.0–10.7 m/s
6 Strong breeze 39–49 km/h 3–4 m Long waves begin to form. White foam crests are very frequent. Some airborne spray is present. Large branches in motion. Whistling heard in overhead wires. Umbrella use becomes difficult. Empty plastic garbage cans tip over. Beaufort scale 6.jpg
25–30 mph
21–26 kn 9–13 ft
10.8–13.8 m/s
7 High wind,
Moderate gale,
Near gale 50–61 km/h 4–5.5 m Sea heaps up. Some foam from breaking waves is blown into streaks along wind direction. Moderate amounts of airborne spray. Whole trees in motion. Effort needed to walk against the wind. Beaufort scale 7.jpg
31–38 mph
27–33 kn 13–19 ft
13.9–17.1 m/s
8 Gale,
Fresh gale 62–74 km/h 5.5–7.5 m Moderately high waves with breaking crests forming spindrift. Well-marked streaks of foam are blown along wind direction. Considerable airborne spray. Some twigs broken from trees. Cars veer on road. Progress on foot is seriously impeded. Beaufort scale 8.jpg
39–46 mph
34–40 kn 18–25 ft
17.2–20.7 m/s
9 Strong gale 75–88 km/h 7–10 m High waves whose crests sometimes roll over. Dense foam is blown along wind direction. Large amounts of airborne spray may begin to reduce visibility. Some branches break off trees, and some small trees blow over. Construction/temporary signs and barricades blow over. Beaufort scale 9.jpg
47–54 mph
41–47 kn 23–32 ft
20.8–24.4 m/s
10 Storm,[6]
Whole gale 89–102 km/h 9–12.5 m Very high waves with overhanging crests. Large patches of foam from wave crests give the sea a white appearance. Considerable tumbling of waves with heavy impact. Large amounts of airborne spray reduce visibility. Trees are broken off or uprooted, saplings bent and deformed. Poorly attached asphalt shingles and shingles in poor condition peel off roofs. Beaufort scale 10.jpg
55–63 mph
48–55 kn 29–41 ft
24.5–28.4 m/s
11 Violent storm 103–117 km/h 11.5–16 m Exceptionally high waves. Very large patches of foam, driven before the wind, cover much of the sea surface. Very large amounts of airborne spray severely reduce visibility. Widespread damage to vegetation. Many roofing surfaces are damaged; asphalt tiles that have curled up and/or fractured due to age may break away completely. Beaufort scale 11.jpg
64–72 mph
56–63 kn 37–52 ft
28.5–32.6 m/s
12 Hurricane[6] ≥ 118 km/h ≥ 14 m Huge waves. Sea is completely white with foam and spray. Air is filled with driving spray, greatly reducing visibility. Very widespread damage to vegetation. Some windows may break; mobile homes and poorly constructed sheds and barns are damaged. Debris may be hurled about. Beaufort scale 12.jpg
≥ 73 mph
≥ 64 kn ≥ 46 ft
≥ 32.7 m/s

The scale is used in the Shipping Forecasts broadcast on BBC Radio 4 in the United Kingdom, and in the Sea Ar

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