Sunscreen matters for open-water divers: protecting skin from sun and water reflections

What is the primary benefit of using sunscreen while diving?

• A. To enhance buoyancy
• B. To prevent sunburn and skin damage
• C. To improve underwater visibility
• D. To increase comfort in cold water

Answer: (B)

Using sunscreen while diving is primarily beneficial for preventing sunburn and skin damage. When divers spend extended periods on or near the surface of the water, they are exposed to ultraviolet (UV) rays from the sun. Water can reflect and intensify UV exposure, making it possible for divers to suffer from sunburn even during relatively short periods spent on the surface or in shallow waters. Applying sunscreen helps create a barrier that protects the skin from harmful UV rays, reducing the risk of both immediate effects like sunburn and long-term damage such as skin cancer or premature aging due to sun exposure. It’s crucial for divers to be aware of the specific environmental conditions they may encounter, including the reflection of sunlight off the water, which increases exposure.

Sun on the surface, salt on your skin, and the shimmer of the water stretching out to the horizon — that’s the kind of scene that makes underwater adventures unforgettable. If you’re earning your IANTD Open Water Diver rating, you already know safety, comfort, and preparation matter as much as the thrill of exploration. One small habit, tucked into your pre-dive routine, makes a big difference: sunscreen.

What’s the single, primary benefit of sunscreen when you’re on a water outing? It’s not buoyancy or visibility, and it isn’t about warmth. It’s to prevent sunburn and skin damage. That’s the headline reason why sunscreen sits in your bag alongside your mask, fins, and wetsuit. Let me explain how that works, and how to choose and use sunscreen so you stay protected underwater and on the surface.

Why sun exposure matters when you’re near the surface

Here’s the thing: even if you’ll spend most of your time below the surface, you’re still outdoors much of the day. You’ll be on a boat, waiting at the surface, or sitting on a sandy beach between legs of your underwater outing. Sunlight doesn’t just hit you from above; it also reflects off the water and can bounce around the surface and shallow areas. That reflection can intensify UV exposure, so you can burn even during relatively short stints spent at the surface or in the shallows.

We’re talking not just about a pink nose. Sun exposure compounds over time, and repeated UV damage can lead to longer-term consequences, including premature aging and, in the worst case, skin cancer. If you’ve ever spent hours under a blazing sun in a T-shirt and shorts and felt that sting later, you know what a big deal this is. The UV rays don’t care whether you’re studying underwater hand signals or adjusting your buoyancy. They’re there, and they add up.

What sunscreen actually does for you on a surface-to-depth journey

• It creates a barrier. Sunscreen either blocks ultraviolet rays or dissipates their energy before they penetrate the skin, depending on the formula. The result is less burning and less immediate irritation, which means more comfortable surface intervals and safer skin in the long run.

• It reduces both short-term pain and long-term risk. A sunburn hurts now, sure, but repeated UV exposure accelerates aging and raises long-term skin-cancer risk. A barrier is a smart, practical shield you don’t want to skip.

• It protects commonly exposed areas. Ears, nose, shoulders, neck, and the back of your hands often take the brunt. For a scuba outing, these areas get missed if you’re focused on keeping a good fit with your mask and hood, so sunscreen acts as a safety net.

• It complements other sun-protection measures. Sunscreen isn’t a standalone solution. It works best with a UV-protective rash guard or shirt, a wide-brim hat when you’re topside, sunglasses with UV protection, and a lip balm with SPF. Think of it as one part of a holistic sun-smart approach.

Choosing the right sunscreen for underwater outings

Not all sunscreens are created equal when you’re near the water, especially if you’re aiming to be reef-friendly and non-greasy enough to wear under a mask or with a hood.

• Broad-spectrum and SPF 30–50. You want protection that covers both UVB (the burn rays) and UVA (the aging rays). A broad-spectrum label is worth listening to.

• Water resistance. Look for “water resistant” on the label, with a duration such as 40 or 80 minutes. This doesn’t mean you can ignore reapplication; it means the sunscreen lasts longer while you’re in the water or sweating. Reapply after towel-drying or after a long surface break, or after any strenuous motion.

• Reef-safe formulations. If you’re in marine environments, reef-safe options are a smart pick. Many divers and instructors prefer mineral sunscreens (titanium dioxide or zinc oxide) or carefully formulated chemical blends that avoid coral-harming ingredients like oxybenzone and octinoxate. It’s a small choice with a big positive effect on underwater ecosystems.

• Lip protection. Don’t forget lip balm with SPF. The lips burn easily, and that sting sticks with you, especially on longer surface periods.

• Easy-on, easy-off texture. You’ll want something that doesn’t leave you greasy or smear onto your mask, hood, or gloves. A light matte finish or a formula rated for water use tends to be friendlier under gear.

Practical tips for applying and reapplying

• Apply early and thoroughly. Put sunscreen on at least 15–30 minutes before you head into high sun or onto the surface. This gives it time to absorb and form a proper protective layer.

• Reapply on schedule. Even if a bottle claims 40–80 minutes of water resistance, reapply at a surface interval every couple of hours, or after heavy sweating, splashing, or wiping off salt. You don’t want to rely on the clock alone—listen to your skin and nerves of the sun’s rays.

• Layering matters. Sunscreen on the face is essential, but don’t neglect ears, the back of the neck, and the tops of shoulders where a sun-angled reflection can hit. If you’re wearing a hood or a high-collar rash guard, you can reduce exposure, but you’ll still want sunscreen for exposed patches.

• Be mindful of gear interference. Sunscreen can smear onto lenses or seals if you rub your face aggressively, and some masks fit snugly with oily residue. Apply sunscreen, then let it settle before you don your mask, hood, and gloves. If you’re wearing a lip balm, let that set too.

• Lip care is part of your protection plan. A flavored or scented lip balm can be nice, but prioritize a balm with a solid SPF rating. Dry lips crack more easily after a long surface period, and that discomfort can steal your focus during a crucial moment in the session.

• Consider the environment. In tropical, cloudless locales, the sun is intense. Even in cooler waters or higher latitudes, UV exposure adds up over the day. Adjust your sunscreen choice and schedule accordingly, and be mindful of reflective surfaces like white sand and bright water.

A few practical gear and routine ideas

• Rash guard or UV shirt. A lightweight, UPF-rated shirt can dramatically cut the surface exposure. It’s a simple swap that reduces sunscreen load and keeps you cooler when the sun’s overhead.

• Hat and sunglasses for surface time. A wide-brim hat can shield your face and neck when you’re topside waiting for the next leg of your journey. Sunglasses with UV protection aren’t just for land—they protect your eyes and reduce glare when you’re watching for boat traffic or marine life near the surface.

• Reef-safe, non-greasy options. If you’re out for a full day, consider a mineral-based sunscreen with a no-residue finish. It tends to stay put longer under a hood or face mask and stays gentler on the reef. Do a quick patch test before a long trip to rule out skin sensitivity.

A quick note on real-world sun exposure

I’ve taken a lot of lessons from people who’ve logged many hours on the surface between depths. Some were surprised to learn how quickly sun exposure adds up when you’ve got a bright day, a reflective surface, and a calm sea. It’s easy to underestimate the power of the sun when you’re focused on depth, currents, or marine life. The truth is simple: sunscreen is a steady shield that protects you across the entire experience, not just when you’re up top.

Linking sun safety to broader safety mindset

Sun protection is a small but meaningful piece of your broader safety mindset. You already have a checklist: buddy system, current charts, surface support, emergency signals, and gear checks. Sunscreen fits into that mindset the same way a reliable mask or a well-inflated buoyancy device does. It’s part of staying comfortable, focused, and ready to respond if something goes amiss—whether you’re finning toward a reef ledge or simply waiting for the next sign from your instructor.

A few memorable scenarios

• Midday, tropics, glassy water. The sun blazes down and the reflection doubles the exposure. Sunscreen plus a UV shirt and a cap-on-boat strategy becomes not just nice-to-have but essential.

• Cloudy day, cooler water. The UV rays still penetrate, especially UVA. Don’t skip sunscreen just because the sky looks gray; you’re still vulnerable to long-term skin effects, even if the burn isn’t immediate.

• Longer surface breaks. If you’re spending extra time on the surface between below-surface sections, sunscreen and shade become your best friends. A lightweight pop-up canopy on the boat can give you a respite without losing time on your schedule.

Bottom line for Open Water adventures

The primary benefit of sunscreen when you’re exploring beneath the surface is straightforward: it prevents sunburn and skin damage. You’re out there to learn, observe, and enjoy, not to pay for sunburn later. With a thoughtful sunscreen choice, plus a little extra protection like a UV shirt and lip SPF, you can turn every surface moment into a comfortable, safe, and enjoyable part of the day.

If you’re ready to take your next underwater excursion with confidence, pick a reef-friendly, broad-spectrum sunscreen with good water resistance, and pack it along with your rash guard, hat, and lip balm. Apply early, reapply as needed, and remember: protection isn’t a hassle—it’s part of the adventure. And when you’re done for the day, you’ll be grateful for a smooth skin routine that helps you keep coming back to the water—again and again, with the same sense of curiosity and calm you bring to every underwater session.

So next time you’re prepping for a day on the water, think about more than the mask and fins. Think about skin health, long-term protection, and how a simple bottle of sunscreen can keep your sun-filled explorations sustainable and enjoyable for years to come. You’ll thank yourself when the skin feels fine, the day stays comfortable, and your focus stays sharp—on the reef, the currents, and the next glow of a sunlit surface.