A sunburn is no joke. Nearly 300 Victorian residents had to go to the hospital after a sunburn during the 2018-2019 summer. A sunburn can cause extreme pain and increase your risk for skin cancer. 

Putting on waterproof sunscreen for swimming is an easy way to protect yourself. But you can't just slap on some water-resistant sunscreen and move on with your day. You need to answer a few questions. 

What are the ingredients in waterproof sunscreen, and how can you start decoding sunscreen labels? How can you know how often to reapply sunscreen? What are the best sunscreen products to buy? 

Answer these questions and you can prevent sunburns without breaking a sweat. Here is your quick guide.

What Makes Sunscreen Waterproof? 

There are two kinds of sunscreen. Physical sunscreen is made with minerals that sit on top of the skin and reflect UV rays away from the body.

Chemical sunscreen absorbs into the top layer of the skin. They can absorb UV rays, but they don't let the rays penetrate deeper into the skin and damage the cells. Most waterproof sunscreens are chemical sunscreens, but they may have a few minerals that sit on the skin.

A sunscreen's active ingredients are the ingredients that protect your skin from sun exposure. These ingredients include oxybenzone and octinoxate. These are chemicals that are not waterproof, so they will slip off your skin if you go swimming and pollute the marine environment.

A manufacturer will add additional ingredients to the active ingredients to make them waterproof. They grip the skin, allowing the sunscreen to stay on after water exposure. They also make the sunscreen water-insoluble so it will not dissolve in the water. 

These additional ingredients include cetyl octanoate. It forms a film over the skin that repels water. You can find cetyl octanoate in a variety of products, including shampoos. 

Many manufacturers no longer call their sunscreen "waterproof." They prefer the term, "water-resistant," so they don't make consumers believe they are completely safe. 

How Long Does Sunscreen Last in the Water? 

In general, waterproof sunscreen lasts up to 80 minutes after water exposure. It may provide some residual protection, but you should reapply it if you've been swimming for a long period. 

But the 80-minute figure is a benchmark. You must wait 20 minutes after you apply your sunscreen before going swimming. If you go into the water before then, the sunscreen may wash off because your skin hasn't absorbed it. 

How you apply your sunscreen also impacts your time. You want to cover every part of your skin that is exposed to sunlight, including your scalp and ears. If you don't rub the sunscreen into your skin, your skin may not absorb it and it may wear off sooner.

Some sunscreens without cetyl octanoate and other ingredients wear off in 40 minutes. Expired sunscreen may wear off in even less time because the chemicals no longer bind to each other. Any sunscreen can wear off if the water is very hot or if you are sweating while you are swimming.

How Often Should You Be Reapplying Waterproof Sunscreen? 

Even if you are not going into the water, you need to reapply your sunscreen every two hours. Unless it contains waxes, physical sunscreens can fall off because they don't settle into the skin.  Chemical sunscreen will stop offering protection once it absorbs UV rays for two hours straight. 

When you are in the water, you need to reapply sunscreen more often. You may need to reapply your screen every hour or so. 

You should dry your skin off before you apply your sunscreen. Once you apply it, you should give your skin 20 minutes to absorb the screen. You can then head back into the water. With physical sunscreens, the waiting time is not required because the active ingredient - such as zinc oxide - sits on top of the skin to reflect UV rays, it is however best to wait a little while your skin soaks in the oils and the waxes settle on top of the skin. 

UV rays are most powerful when the sun is highest in the sky. This is usually between the hours of 10am and 2pm, though the sun is still high during summer afternoons. You may want to apply your sunscreen once an hour if you are out during these times.

Clouds reflect some UV rays, but not all. You should be reapplying your sunscreen even if it is overcast.

If you notice the symptoms of sunburn, you should apply your sunscreen right away. You should also move to a shaded area and cover the burned area with a piece of clothing.

Is Waterproof Sunscreen Bad for the Environment?

Though you should wear sunscreen for your health, you should consider its impact on the environment. Many sunscreen ingredients are toxic to sea creatures, including oxybenzone, octinoxate, octocrylene and avobenzone and several benzophenones. Wearing a water-resistant sunscreen and applying your sunscreen 20 minutes before entering the ocean can help minimise the leaching off ingredients into the environment when you swim. However, it is now understood that the chemicals absorbed into the skin are absorbed into urine and enter our waterways through the sewage!

You can further minimize the effects of your chemical sunscreen by complementing with sun protection clothing, such as rash vests and wetsuits. This way you can limit sunscreen application to very sensitive areas and avoid excessive leaching into the sensitive ecosystems such as coral reefs.

A better way is to choose reef-safe water-resistant sunscreen.

What Are the Safest Waterproof Products? 

Mineral sunscreens with natural ingredients tend to be the safest ones. The skin can absorb them easily, and the active ingredients can reflect UV rays away. They also do not dry out the skin or hurt sea creatures in any way. 

You can try People4Ocean natural SPF 30 sunscreen with zinc oxide and essential oils. The active compound Zinc oxide sits on top of your skin and reflect UV rays like a mirror. This sunscreen contains Tasmanian Beeswax to ensure water-resistance. Finally, safflower seed and lavender oils keep the skin healthy, even after you've been sunburned. 

If you are spending extensive time outdoors or in the surf, you can use Peopl4Ocean SPF 50+ zinc stick. In addition to zinc oxide, it contains coconut oil and candelilla wax. Candelilla wax is a common ingredient in many lip balms, so it can help keep your skin moist while ensuring water-resistance. 

You can also get an SPF 50 sunscreen in travel size bottle form. The sunscreen is vegan and all-natural, containing essential oils like coconut oil. 

The Answers You Deserve About Waterproof Sunscreen

Water-resistant sunscreen can be a lifesaver, although - for the chemical types - this means adding several ingredients on your skin. Most waterproof  sunscreen can remain on the skin for up to 80 minutes after water exposure.

You may need to reapply sooner. You should put sunscreen on every hour if you're out in the early afternoon or in the water. 

Keep in mind that the ingredients in sunscreen can hurt marine life. Try minimise sunscreen application, or find a sunscreen with natural & reef-safe ingredients. 

You don't have to go far. People4Ocean provides effective and naturally water-resistant sunscreens. Browse our products today.