Why You Can Get Sunburned in the Pool (Easy Explanation)


Going to the local pool is a fun experience for families to look forward to during those hot and sunny days. Nonetheless, there are a few unpleasant side effects that come with swimming around in the pool for too long.

You can get sunburned in the pool because harmful UV rays are able to pass through water and penetrate the skin. Pool-goers are typically more vulnerable to sunburn since swimsuits uncover more skin relative to normal clothes and sunblock can be rinsed away by the water.

Read further to get an even more in-depth explanation about why those that spend hours in the pool will likely be sunburned by the time they exit the water. Stay until the end to discover some of the best practices for avoiding sunburn while swimming in the pool.

Why Getting Sunburned in the Pool is Possible

UV Light Penetrates Through Water

Sunburns are a direct consequence of too much exposure to ultraviolet (UV) light. It is common knowledge that exposed skin can absorb UV light through air, but what about water?

UV light can reach down through the water’s surface. Contrary to popular opinion, water does not act as a strong protective barrier against the sun’s rays. According to a recent study, three feet of water only stops approximately 20% of UV rays (source). This small percentage of blockage is not nearly enough to prevent sunburn. Unfortunately, the 80% of UV rays that penetrate through water are more than enough to harm your skin.

Since pool-goers spend the majority of their time up near the water’s surface in this three foot range, sunburn is a real possibility. The more time that’s spent in the pool away from the shade, the greater the chances of sunburn. Thus, you should take the same precautionary measures that you would on land when swimming in the pool.

On certain pool days, the UV light radiating from the sun can be especially harsh. Under these circumstances, these harsh UV rays can easily pass through water and cause sunburn at a much more rapid rate.

To get an indication of what the UV levels are currently at, you should refer to the UV index for your local area. Put simply, the UV index is a measure of sunburn vulnerability if you choose not to wear any sun protection. A basic interpretation of the UV index scale is provided in the chart below (source):

UV IndexSunburn Risk PotentialAverage Time to Burn
0-2Low60 minutes
3-5Moderate30-45 minutes
6-7High15-25 minutes
8-10Very High>15 minutes
11+Extreme>10 minutes

Depending upon your skin type and the UV level, you should plan your pool day accordingly to keep your skin in healthy condition.

Swimwear Exposes More Skin than Normal Clothes

Another major reason why you can get sunburned in the pool is that standard swimwear leaves considerably more skin open to the negative effects of the sun. In general, regular clothes provide better coverage of the:

  • back
  • shoulders
  • thighs

While there may be certain exceptions to this rule, most people will find that their sunburn risk increases when wearing a swimsuit.

It’s important to note that both regular clothes and swimsuits provide varying levels of UV protection, so you should select your pool outfit carefully. If you’re concerned about getting sunburned at the pool, it’s in your best interest to wear fabric that’s darker and more tightly woven, since this type of fabric provides slightly more UV protection. Additionally, it’s worth keeping in mind that wet fabric leaves you more vulnerable to harmful UV rays compared to dry fabric (source).

If you choose to forgo a protective clothing layer, the only true protection you can rely upon for these exposed areas is sunblock. As we will discuss next, sunblock is not always 100% effective in pool water.

Sunscreen Can Wash Off in the Pool

Applying sunblock regularly will definitely help in warding off the effects of the sun, but only to a certain extent. Swimming around in pool water for long durations will eventually rinse away some of the sunscreen on your body. This is because sunblock is water-resistant, not waterproof (source). These two terms are not synonymous with one another, contrary to popular belief.

The rinsing effect of pool water is not the only culprit, however. Natural bodily processes—such as perspiration and skin absorption—can also slowly strip away sunscreen and thereby reduce its effectiveness. Oftentimes, people get so distracted by pool activities that they’re not even aware that any of these factors are working against them.

Applying sunscreen just once is not enough to last an entire day at the pool. Sadly, there are a great deal of pool-goers that believe otherwise. This mistaken belief gives them a false sense of security, which usually leads to serious sunburn. Regardless of whether you’re in the pool or out of the pool, continual application of sunscreen is a must.

Do You Sunburn More In or Out of the Pool?

After discovering that sunburns can arise in the pool, the first thought that pops into people’s minds is whether they will sunburn faster in the water or out of the water.

Although there’s still controversy surrounding this subject, it’s thought that being in pool water does not inherently increase sunburn risk. In other words, being on land or in water does not automatically magnify the harmful effects of the sun in and of itself. In reality, any additional sunburn that occurs in the pool can be attributed to other factors, such as:

  • Cooling Effect of Water – The chilled temperature of pool water can mask the onset of a sunburn. This pain alleviation makes it far less likely for you to recognize the warning signs associated with sunburn. As a result, these sunburns only worsen with time. It goes without saying, but sunburns will continue to arise if the problem is not addressed early on.
  • Less Skin Coverage – We touched on it earlier, but normal swim attire exposes considerably more skin to harmful UV rays. This convinces swimmers that they’ve sunburned more as a result of the water, not their chosen outfit.
  • Not Enough Shade – Recreational pools are typically placed out in the open, without any hint of shade nearby. Any person that spends all day in the water is bound to be at the mercy of the sun relative to those on land. With land activities, such as walking around the park or hiking on a trail, the surrounding environment provides at least some semblance of shade to mitigate sun overexposure.
  • Reduced Effectiveness of Sunscreen – Again, the time interval that sunscreen actually works is slightly less in water relative to land. For this reason, some people are under the false impression that any additional sunburns occur because of the water itself, not the diminished functionality of their sunblock.

In my own experience, I’ve noticed that I sunburn much more inside the pool than outside because of these other factors. Just like everyone else, I have trouble remembering to re-apply sunblock once I’m actually swimming around the pool. Being both cooled by the water and distracted by swimming makes it extremely difficult for me to keep constant tabs on my skin health.

There’s an argument that people sunburn more in water because of its reflective properties. Those that subscribe to this idea believe that this reflection strengthens the sun’s rays and concentrates them onto the skin via water droplets.

Currently, there’s no scientific evidence to back up this claim. In fact, this argument has been largely diminished after the World Health Organization (WHO) released a study proving that the UV reflection from water is practically equivalent to that of both grass and soil (source).

Whatever idea you personally subscribe to, be sure to monitor your exposure to the sun whether you’re in or out of the pool. At the end of the day, your safety is all that matters.

Best Practices to Stay Sunburn-Free in the Pool

Speaking of safety, there are a few precautionary measures you should get into the habit of implementing in order to avoid sunburns. There’s no guarantee that these practices will keep you completely sunburn-free, but they will greatly mitigate your sunburn risk in the pool.

  • Allow Your Sunscreen 20 Minutes to Set In – It can be tempting to jump into the water as soon as you’ve applied your sunblock, but this increases the chances of your sun protection washing off. It’s far better to stay out of the water for at least 20 minutes, as this provides your sunblock the opportunity to be absorbed into the skin and do its job.
  • Buy Sunblock with a Higher SPF – Depending on your skin type, you may be more susceptible to sunburn compared to others. If you sunburn easily, make sure to purchase the appropriate sunblock product. For those of you that do not know, SPF stands for sun protection factor. The higher the SPF of your sunblock, the less susceptible you are to sunburn.
  • Re-Apply Sunscreen Every Hour – Since sunblock has a tendency to wash off in the pool, you should make a concerted effort to get out of the pool every hour to re-apply another layer of sunblock. This way, there’s a sustained layer of protection between the sun and your skin. In the absence of this layer, sunburn is practically a foregone conclusion for those that have fairer skin.
  • Wear a Wide-Brimmed Sunhat – Facial sunburns are a problem for many pool-goers, especially if they fail to re-apply sunblock every hour. A wide-brimmed sunhat offers precious shade to swimmers that desperately need it. You may not be able to swim underwater, but it certainly beats dealing with the after-effects of a severe sunburn. Personally, just wearing a simple bucket hat has saved me from countless sunburns on my face. So if you have yet to wear a bucket hat to the pool, I highly recommend that you try it out yourself!

Sources: 1 2 3 4

Austin Carmody

I am the owner of HydroPursuit. I enjoy kicking back and getting out on the water as much as I can in my free time.

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