BOAT-COMPARATOR Guide
Sun and heat on board: staying protected at sea
Reflection off the water amplifies sun exposure: sunscreen, hydration, heatstroke warning signs — what to know before a day on a boat.
On the water, sun exposure is stronger than on land: reflection off the surface adds to direct rays, and the apparent wind from moving often masks how much heat you're actually taking on. Enough to get sunburnt, or worse, without noticing in time.
Reflection, an underrated trap
Water and a light-coloured deck bounce part of the UV back up toward the face and the underside of arms — areas people protect less carefully than at the beach. A hazy sky doesn't reduce this risk: some of the worst sunburns at sea happen on slightly overcast days, when vigilance naturally drops.
The right protective habits
- Reapply sunscreen every two hours and after every swim, including on areas shaded by the bimini.
- A light long-sleeved UV shirt for long crossings, a hat with a chin strap so it doesn't blow away, and category-3 sunglasses.
- Shade available on board: bimini, awning or parasol, especially useful with children aboard.
Staying hydrated all day
Drink regularly, without waiting to feel thirsty, and go easy on alcohol, which speeds up dehydration: heat and salt spray increase water loss far faster than an ordinary day ashore.
Recognising heatstroke
Headache, dizziness, nausea, hot and dry skin: these signs call for moving into shade, cooling down with a damp cloth, hydrating right away, and seeking help if confusion or symptoms persist. See also our sailing with kids guide and our marine heatwave guide if you'd rather pick a cooler stretch of water.
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