What is SPF?

SPF (Sun Protection Factor) represents the numbers on sunscreen labels that indicate how much UVB protection the product offers. In this blog, we'll explore what these numbers actually mean, explain the difference between UVA and UVB rays, and discuss how SPF is calculated. Yes, we’ll even break down the math! We will also cover the importance of choosing broad-spectrum sunscreen for full protection, address proper sunscreen application, and the common mistakes people make. Reapplication is critical to maintaining sun protection, and we will explain why. The blog also covers the complete sun protection strategy, including using sunscreen alongside UPF clothing and accessories. Finally, we provide product recommendations for women, men, kids, and babies to help you stay safe this summer.

Now, let's explore what you need to know to enjoy the sun!

What It Means, How It Works, and Why Proper Application Is Essential

Sunscreen has become an essential part of everyone’s routine. Most people instinctively reach for the bottle with the highest SPF, thinking, “bigger is better.” But what do these SPF numbers truly mean? Does SPF 50+ automatically guarantee better protection than SPF 30+?

In this post, we will break down the meaning of SPF, the difference between UVA and UVB rays, and why proper application is key to getting the full benefits of sunscreen. We’ll also discuss the importance of reapplication, debunk common misconceptions, and explain why sunscreen is just one part of an effective sun protection strategy.

What Does SPF Stand For?

SPF stands for Sun Protection Factor, and the number next to it indicates how well the sunscreen protects against sunburn caused by UVB rays. The higher the SPF, the better it filters out UVB rays, which are primarily responsible for sunburns and contribute to skin cancer. According to a CNN article on sunscreen use, understanding what SPF numbers mean is crucial for selecting the right protection for your skin type.

However, SPF is not a measure of time. It’s a common misconception that SPF tells you how long you can stay outdoors in the sun without burning. Instead, it measures how much longer it takes untanned skin to start reddening when sunscreen is applied, compared to when no sunscreen is used.

How SPF Is Determined

SPF is calculated through laboratory testing, where sunscreen is applied generously to a patch of untanned skin—usually the buttocks of volunteers. The skin is then exposed to simulated UVB rays, and the time it takes to develop minimal redness with and without sunscreen is measured.

To calculate the SPF, the time it takes for skin to redden with sunscreen is divided by the time it takes to redden without it. For example, if it takes 300 seconds for skin to burn with sunscreen and 10 seconds without it, the SPF would be 30 (300 ÷ 10 = 30).

SPF only measures protection against UVB rays, not UVA rays. UVA rays penetrate deeper into the skin, causing long-term damage like premature aging and skin cancer. To protect against both types of radiation, you need a broad-spectrum sunscreen.

SPF only measures protection against UVB rays. For comprehensive sun protection, you need a broad-spectrum sunscreen that shields you from both UVB and UVA rays, as highlighted by ABC News in a dermatologist’s guide.

Understanding UVA and UVB Rays

While UVB rays cause sunburn, UVA rays penetrate deeper into the skin, causing long-term damage such as wrinkles, premature aging, and skin cancer, including melanoma. Unlike UVB rays, UVA rays are present year-round and can penetrate through clouds and windows, making protection necessary even on overcast days.

Choosing a sunscreen labeled as broad-spectrum ensures protection against both UVA and UVB rays, providing more comprehensive defense against sun damage. An NBC News article covers how people often overlook the need for UVA protection and make sunscreen mistakes, reducing its effectiveness.

Proper Sunscreen Application Is Essential

Even the highest SPF sunscreen won’t provide adequate protection if it’s not applied properly. Studies show that most people apply only one-third of the recommended amount, drastically reducing the effectiveness of the sunscreen.

Here’s why it matters: If you apply an SPF 30 sunscreen too thinly, you might only be getting the protection of SPF 10. To achieve the full level of protection indicated on the bottle, you need to apply sunscreen generously.

How Much Sunscreen to Use

Dermatologists recommend the following guidelines for proper sunscreen application:

• Face and neck: About a nickel-sized amount
• Full body: About three tablespoons of sunscreen (the size of a shot glass)

For more on how to avoid sunburn, check out this CBS News article, which highlights best practices for using sunscreen.

Don’t Forget These Commonly Missed Areas:

• Ears
• Tops of feet
• Backs of legs and knees
• Scalp (if you have thinning hair)
• Back of the neck

Neglecting these areas can result in unintended burns or cumulative UV damage over time.

Reapply Frequently

Even when applied correctly, sunscreen can wear off due to sweat, swimming, or just regular skin contact. Dermatologists recommend reapplying sunscreen every two hours and immediately after swimming or sweating.

Water-resistant sunscreens offer protection for 40 to 80 minutes in the water, but you’ll need to reapply afterward to maintain the same level of protection.

SPF: Does Higher Always Mean Better?

Mathematically, higher SPF values provide better protection, but the difference isn’t always as significant as you might think. For instance:

• SPF 30 blocks about 96% of UVB rays
• SPF 50+ blocks about 98% of UVB rays

The additional protection offered by higher SPF values is relatively small, but for people with fair skin, those prone to sunburn, or with a family history of skin cancer, every extra bit of protection can make a difference. However, applying sunscreen properly and reapplying regularly is far more critical than choosing an SPF number.

"An SPF 30 sunscreen applied correctly offers better protection than an SPF 50+ sunscreen applied too thinly," according to USA Today.

Sunscreen Is Only One Part of Sun Protection

Sunscreen is vital, but it should be part of a broader strategy to protect your skin. No sunscreen can block 100% of UV rays, so it’s essential to combine sunscreen with other protective measures.

The Complete Sun Protection Strategy

• Seek Shade: Especially during peak UV hours, from 10 a.m. to 4 p.m.
• Wear Sun-Protective Clothing: Consider clothing with UPF (Ultraviolet Protection Factor), like long sleeves, hats, and sunglasses. Fabrics such as Coolibar’s offer UPF 50+ protection, blocking 98% of UV rays.
• Use Sunscreen: Reapply every two hours and use enough to cover all exposed areas.
• Wear Sunglasses: Choose glasses that block 100% of UVA and UVB rays.

Common Sunscreen Myths Debunked

• Myth: A higher SPF means I don’t need to reapply sunscreen as often.

  False. Regardless of SPF, reapply every two hours and after swimming or sweating.

• Myth: Sunscreen is only needed on sunny days.

  False. UVA rays can penetrate clouds, so sunscreen is necessary even on overcast days.

• Myth: Sunscreen with a high SPF blocks all UV radiation.

  False. No sunscreen can block 100% of UV rays; SPF 50+ sunscreens only block about 98%.

Coolibar Product Recommendations for Whole Family Sun Protection

To complement your sunscreen routine, consider sun-protective clothing from Coolibar, which offers UPF 50+ protection to block 98% of UV rays. Below are recommendations for women, men, kids, and babies, including a hat for each group to ensure maximum coverage.

Women’s Sun Protection

• Ceylon UV Shawl Wrap Style: 10388

  A versatile and elegant wrap for added sun coverage on the go, ideal for travel and casual wear.

• LumaLeo Long Sleeve T-Shirt Style: 10359

  Lightweight and breathable, this long sleeve shirt offers UPF 50+ protection with moisture-wicking fabric to keep you cool.

• Women's Fabyan Maxi Skirt Style: 10268

  Stylish and functional, this skirt is perfect for summer outings, combining fashion with sun protection.

• Women's Aubrey Wide Brim Beach Hat Style: 02370

  A classic sun hat with a 4-inch brim, offering full coverage for your face, ears, and neck while lounging or out in the sun.

Men’s Sun Protection

• Men's Aricia Sun Shirt Style: 01566

  A casual Sun Shirt designed for outdoor activity with built-in UV protection and a comfortable fit for any adventure.

• Men's Outpace Sport Pants Style: 01598

  Lightweight, durable, and perfect for hiking or outdoor sports. These pants provide excellent sun protection with quick-dry capabilities.

• Men's Sonora Quarter-Zip Style: 10078

  Versatile and designed for travel or casual wear, this pullover combines comfort and sun protection in one.

• Landon Reversible Bucket Hat Style: 02556

  A stylish bucket hat with a wide brim, offering 360-degree protection for your head and face during outdoor activities.

Kids’ Sun Protection

• Kid's LumaLeo Hoodie Style : 10453

  Lightweight and fun, this hoodie keeps kids cool and protected from the sun during outdoor play.

• Boy's Outpace Sport Shorts Style: 01820

  Comfortable, stretchy, and sun-protective, these shorts are perfect for active kids spending time outdoors.

• Boy's Outpace Sport Pants Style: 01822

  Sport pants so comfortable and lightweight he won't even know they’re keeping UV rays at bay, but you will!

• Kid's Surfs Up Bucket Hat Style: 02736

  Here’s a kid’s SPF hat built for any waterfront activity, from wading to swimming to pool play.

Baby Sun Protection

• Baby Beach One-Piece Swimsuit Style: 03704

  Protecting skin from the sun starts at day one! Comfy design, fun patterns and unbeatable sun protection is what our Baby Beach One-Piece Swimsuit is all about.

• Baby Batibou Sun Blanket Style: 07055M

  Harmful UV Rays don't stand a chance against our ultra soft Sun Protective Blanket, that works like a sun shield.

• Baby Island Rash Guard Set Style: 10686

  Protecting your little fish in a true UPF 50+ swim outfit has never been easier.

• Baby Splashy All Sport Hat

  A baseball style swim cap that's safe for baby. Our Splashy All Sport Hat has a 2 ¾" foam brim that holds its shape and flexes for comfort.

Conclusion: Sunscreen as Part of Your Daily Routine

As summer approaches, make sunscreen part of your daily routine. But don’t just grab the bottle with the highest SPF. Proper application, reapplication, and broad-spectrum protection are key to shielding your skin from both UVB and UVA rays.

Sunscreen is just one piece of the sun protection puzzle. Be sure to wear protective clothing, seek shade, and use UV-blocking sunglasses to ensure your skin stays healthy and protected. Whether you’re heading to the beach or just running errands, slip on a shirt, slap on a hat, slather on sunscreen, and slide on some sunglasses.

By combining these practices, you can enjoy the outdoors safely and reduce your risk of sunburn, premature aging, and skin cancer.