Stay Safe Indoors: Understanding The Sun’s Rays And Why Sunscreen Works Inside, Too

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Seasons may change but the sun doesn’t take a break, which means your skin protection shouldn’t, either - even if you’re spending more time indoors. Now is the perfect time to ramp up your sunscreen use and get in the habit of applying it both inside and outside to stay safe.

These risks can be severe if neglected. With proper precautions, you can reduce exposure to harmful rays and prevent damage. Understanding solar ultraviolet (UV) radiation is crucial in grasping the seriousness of skin damage and why sunscreen is a must, even inside.

Understanding UV Rays And Their Risks

UV rays can damage your skin cells with any sun exposure. Your body is most susceptible to these dangers between 10 a.m. and 4 p.m., known as peak daylight hours. Even in winter, UV levels remain high regardless of cloud coverage, posing a risk year-round.

Two types of UV rays reach the earth and affect our bodies: Ultraviolet-A (UV-A) and Ultraviolet-B (UV-B). UV-A rays cause tanning, skin aging and contribute to sunburns. They penetrate deeper into the skin than UV-B rays and can go through glass depending on its type, color and thickness.

These rays don’t just infiltrate glass, they strike your skin’s dermis, a dense layer that protects blood vessels and nerves, breaking down collagen and elastic fibers. The American Cancer Society notes that consistent exposure can lead to serious skin damage, including cancer.

Similarly, UV-B rays target the skin’s surface, causing sunburns and increasing skin cancer risk. However, these rays don’t penetrate glass.

Indoor UV Exposure Risks

While your home’s windows can offer some protection, they don’t eliminate all risks. Sitting by a window can expose you to more UV radiation than you might think, making it akin to sitting outdoors.

Melanin acts as a natural sunscreen, absorbing UV light and converting it into heat, which gives skin and hair their pigmentation. When your skin is damaged by UV rays, your body sends melanin to protect the area, which can cause darker skin.

Continued exposure to UV radiation can overwhelm the body's defenses, leading to sunburn. Thin or broken cloud cover doesn't fully protect you from skin damage, as UV rays can still penetrate and cause harm.

According to the Health Physics Society, windows typically block UV-B rays but allow UV-A rays through, both at home and in cars. Car windshields can block about 95% of UV-A rays with two panes of glass and a clear plastic layer shielding the driver and passengers at the front of the vehicle.

Air Travel Risks

Airplanes can pose greater danger to the skin, due to proximity to the sun at high altitudes. A research study found that pilots and flight crews have higher melanoma risk than other professions.

On average, crew members who developed melanoma were 42% more likely to die early than the general population. The insufficient protection from airplane windows and reduced cloud cover make flying comparable to a tanning bed session.

Clouds block less sunlight at high altitudes, where atmospheric density is thinner, filtering significantly less solar radiation than at ground level. UV radiation increases by 6-10% for every 1,000 feet of altitude, with exposure doubling at cruising altitudes of 30,000 to 40,000 feet.

Low airplane humidity already dries and sensitizes skin, and combined with high altitude UV exposure and air recirculation, it can severely affect your skin.

Blue Light Risks

The main source of blue light is sunlight, but synthetic sources from frequent technology use expose us more, which is believed to contribute to early skin aging and hyperpigmentation.

You may not feel the immediate effects of the sun’s shine or a phone screen because your body uses its antioxidant defenses to curb the harm.

Instead, small amounts of radicals that make it through the body's defenses can accumulate and cause permanent damage over time, making reapplying sunscreen a must.

Choosing The Right Sunscreen

The American Academy of Dermatology Association recommends using a broad-spectrum sunscreen with SPF 30 or higher to block both UV-A and UV-B rays.

Mineral-based sunscreens use physical blockers like iron oxide and titanium dioxide, creating a barrier on the skin’s surface.

Chemical-based sunscreens absorb into the skin, converting UV rays into heat for your skin to release. Regularly applying sunscreen throughout the day, even indoors, ensures continuous protection. Make skin protection a constant part of your skincare regimen.