July 3, 2025—If you're heading outside this summer, you probably know to slop on some sunscreen first. But you might not think about it when you spend the day indoors—or on the road.
Even inside, your skin isn't entirely sheltered from ultraviolet (UV) rays, warns the Skin Cancer Foundation. And that UV exposure can increase your risk for skin cancer and cause premature aging.
Watch out for windows
There are two types of UV rays. They both damage skin, but it's UVB rays that are more likely to cause sunburn. UVA rays penetrate more deeply, damaging collagen and causing age-related skin changes such as wrinkles.
Glass windows block most UVB rays but only about half of UVA rays. That means you can still be exposed to UV rays from the sun:
- At work or home, if you spend time near a window.
- In the car. Windshields offer some UV ray protection, but side windows typically do not.
- On airplanes. UVA exposure is greater at higher altitudes.
The sun isn't the only source of skin damage, especially for people with conditions that make them extra-sensitive to UV radiation, warns the Lupus Foundation of America. Fluorescent and halogen light bulbs can also emit UV rays.
What about light from screens and other devices? That blue light has not been linked to cancer, says the Skin Cancer Foundation. But it can contribute to skin aging.
Save your skin
According to the Skin Cancer Foundation, you can take steps to protect your skin indoors:
- Wear broad-spectrum sunscreen with a minimum SPF of 30 every day.
- Always wear sunglasses and a hat when you're driving in daylight. For extra protection, consider adding UV-blocking film to car windows.
- If you're planning a long drive or flight, wear long-sleeved clothing.
- On airplanes, keep your window shade down if you can.
- Pack a small container of sunscreen in your carry-on luggage so that you can reapply it as needed during a long flight.
A bonus tip: Apply sunscreen to your hands before a gel manicure. Ask for an air fan dry if getting a traditional manicure.
Care for your skin this summer
Heading outside? Staying sun-safe can help prevent skin cancer, sunburn and premature aging.
Sources
- Lupus Foundation of America. "Tips for Managing Sensitivity to Light." https://www.lupus.org/resources/tips-for-managing-sensitivity-to-light.
- Lupus Foundation of America. "UV Exposure: What You Need to Know." https://www.lupus.org/resources/uv-exposure-what-you-need-to-know.
- Skin Cancer Foundation. "5 Sneaky Ways You're Being Exposed to the Sun's UV Rays." https://www.skincancer.org/blog/sneaky-ways-youre-being-exposed-to-the-suns-uv-rays.
- Skin Cancer Foundation. "A Surprising Danger in Planes, Trains and Automobiles." https://www.skincancer.org/blog/surprising-danger-planes-trains-automobiles.
- Skin Cancer Foundation. "Not All UV Rays Stay Outside: How Window Film Can Help Protect You." https://www.skincancer.org/blog/not-all-uv-rays-stay-outside-how-window-film-can-help-protect-you.
- Skin Cancer Foundation. "Photoaging: What You Need to Know About the Other Kind of Aging." https://www.skincancer.org/blog/photoaging-what-you-need-to-know.