How long can you tan in UV 1?
At UV 1, skin type II reaches the first redness in about 2 h 47 with no sunscreen, and about over 24 h with SPF 30. Type I has 2 h 13; type VI has 6 h 40. UV 1 is in the low band (0–2).
A British or Irish midday between November and January, the first hour after sunrise in July, or any overcast winter afternoon.
Today in Columbus
UV 0 right now (low) · peak UV 8.6 at 14:00 · skin type II window 11:07–11:35 and 16:36–17:49
- 14:00 Peak UV hour
- 19 min Time to redness at peak, type II
- 11:07–11:35 First of 2 windows
- 11:20–17:13 Protection recommended (UV 3+, WHO)
Burn times at UV 1, by skin type and SPF
| Skin type | No SPF | SPF 15 | SPF 30 | SPF 50 |
|---|---|---|---|---|
| I — Always burns, never tans. | 2 h 13 | over 24 h | over 24 h | over 24 h |
| II — Burns easily, tans minimally. | 2 h 47 | over 24 h | over 24 h | over 24 h |
| III — Burns moderately, tans gradually. | 3 h 20 | over 24 h | over 24 h | over 24 h |
| IV — Burns rarely, tans easily. | 4 h 27 | over 24 h | over 24 h | over 24 h |
| V — Burns very rarely, tans very easily. | 5 h 33 | over 24 h | over 24 h | over 24 h |
| VI — Almost never burns, always tans. | 6 h 40 | over 24 h | over 24 h | over 24 h |
Every figure is 0.667 × MED ÷ UV, the standard erythemal formula. The MED values are
the published Fitzpatrick doses: 200 to 600 J/m² from type I to type VI. See the full method.
What UV 1 actually means
UV 1 is below the threshold where skin reacts at all. Melanin production needs roughly UV 2 and above, so no amount of time at UV 1 produces colour. It is also the level at which the burn calculation stops being useful: every skin type would need more than a full day of continuous sun to reach the first redness.
What to do: Nothing to plan and nothing to protect against. If you are outside for the light rather than the tan, this is a good level for it.
Official guidance for the low band (0–2): No protection needed for most people. Too weak to build a tan.
Your skin type at UV 1
- Type I — 2 h 13 Always burns, never tans. Limit: UV 3.3.
- Type II — 2 h 47 Burns easily, tans minimally. Limit: UV 4.2.
- Type III — 3 h 20 Burns moderately, tans gradually. Limit: UV 5.
- Type IV — 4 h 27 Burns rarely, tans easily. Limit: UV 6.7.
- Type V — 5 h 33 Burns very rarely, tans very easily. Limit: UV 8.3.
- Type VI — 6 h 40 Almost never burns, always tans. Limit: UV 10.
Where the sun is strongest right now
Nowhere we track peaks at exactly UV 1 on its current forecast day. Here is where the sun is strongest instead.
- Brighton — UV 6.5High · United Kingdom · peak at 13:00 · type II window 10:00–10:22
- Bristol — UV 6.3High · United Kingdom · peak at 13:00 · type II window 11:17–12:12
- Cardiff — UV 5.8High · United Kingdom · peak at 13:00 · type II window 11:17–12:18
UV 1 — the questions people actually ask
How long can you stay in UV 1 without burning?
At UV 1, unprotected skin reaches the first visible redness after about 2 h 13 for Fitzpatrick type I, 2 h 47 for type II, 3 h 20 for type III and 6 h 40 for type VI. Those figures assume a clear sky, sea level, and no reflective surface.
Is UV 1 strong enough to tan?
No. Skin needs roughly UV 2 before melanin production starts, so UV 1 produces no colour however long you stay out.
How long can you stay in UV 1 with SPF 30?
SPF 30 multiplies the unprotected time by 30 in laboratory conditions, so type II goes from about 2 h 47 to about over 24 h at UV 1. Real-world protection is usually lower because most people apply about a quarter of the tested amount, and because sunscreen comes off with water and towels.
Does cloud cover change how long you can tan at UV 1?
Less than people expect. A completely overcast sky cuts UV 1 to roughly UV 0.3; a half-covered sky cuts it by about 7%. That is why sunburn on a grey day is common — the heat drops far more than the UV does.
What is the safe UV limit for my skin type?
UV Hour uses one rule: stay below the UV level that leaves at least 40 minutes before the first redness. That gives UV 3.3 for type I, UV 4.2 for type II, UV 5 for type III and UV 10 for type VI. At UV 1, types I, II, III, IV, V, VI still do.