Photokeratitis and UV Rays: Why Eye Protection Matters in Summer

 It’s a great time for both singles and families to take a break in the summer. So, where do you plan to go during this time? Many people take advantage of work vacations and children’s summer holidays to arrange outdoor trips, including hiking and biking in the wilderness or swimming and surfing at the beach. Under the hot sunshine, many people will be mindful of protecting their skin from UV rays, but eye protection is often overlooked. This oversight may lead to photokeratitis.

What Is Photokeratitis?

Photokeratitis is an acute corneal injury caused by excessive exposure of the eye to UV radiation. Snow blindness and welding flash are also common forms of photokeratitis. Many people have learned about snow blindness through movies but have limited knowledge and awareness of summer photokeratitis. In summer, the sunlight is more intense, and UV radiation is stronger. Outdoor environments such as beaches and water reflect UV rays, which can easily enter the eyes and cause eye damage.

Who Is Vulnerable to Photokeratitis?

During the summer, it’s necessary for people to protect their eyes from UV rays. Several environmental and occupational factors can raise the risk of developing photokeratitis, including unprotected UV exposure, reflected sunlight, and certain artificial UV sources (Peralta, 2023). The following groups of people are vulnerable to UV damage. Check if you belong to any of these groups and take precautions in advance.

3.1 Residents in Sunbelt Regions

The Sunbelt primarily refers to certain states in the southern and southwestern United States (California, Florida, etc.), as well as parts of the southeastern, midwestern, and high-altitude regions (North and South Carolina, Colorado, Utah, etc.). These areas feature warm climates with abundant sunshine, and UV rays are stronger in summer. Also, they are located at lower latitudes, where sunlight strikes the ground at a steeper angle, resulting in stronger solar radiation. The UV index during summer often reaches “high” or “extreme” levels (UV Index 8-11).

Additionally, the Sunbelt has more sunny days compared to other regions of the U.S., leading to longer exposure to UV. For example, Phoenix in Arizona has over 300 sunny days a year, and Florida is also known for its sunny weather. The Sunbelt is a popular summer destination in the United States. People come here to vacation at the beaches, surfing, swimming, and sunbathing. However, the sand and water surfaces reflect intense UV rays, increasing the risk of photokeratitis.

3.2 Residents in High-Altitude Regions

High-altitude regions overlap with parts of the Sunbelt areas. High-altitude regions primarily include Colorado, Utah, New Mexico, Arizona, Nevada, Wyoming, Montana, Iowa, and others. These states feature mountainous and plateau terrain, with elevations typically above 1,500 meters, making them popular destinations for mountaineering, hiking, camping, and paragliding.

The increase in UV radiation with altitude was examined in the Alps, revealing that UV-B increased by approximately 12% per 1000 meters, while UV-A increased by 8–9% per 1000 meters (Blumthaler, Ambach, & Ellinger, 1997). At higher altitudes, the air is thinner and there are fewer clouds, so sunny days are more frequent. Additionally, snow or rock surfaces reflect UV rays, further intensifying the UV exposure. Prolonged activities in these environments can easily cause UV injuries to the eyes.

3.3 Road Cyclists and Travelers to Canyons or Deserts

The Pacific Coast Highway, Blue Ridge Parkway, and Route 66 are all classic cycling routes popular among road cyclists. Pavement surfaces reflect UV rays, and cyclists often spend a longer time outdoors under UV exposure. Also, summer is the peak travel season for the Grand Canyon and Zion National Park, where the canyon and desert landscapes are breathtakingly beautiful. The canyons and deserts reflect intense UV rays, so it is important to protect your skin and prevent your eyes from photokeratitis.

3.4 Outdoor Workers

Approximately 20 million people in the United States work outdoors, including construction workers, farmers, traffic police officers, etc. Their exposure to UV radiation increases significantly in summer. With the popularity of summer water sports, lifeguards and other water activity professionals are also at risk of overexposure to UV rays. Additionally, while welders may be exposed to UV rays year-round, the high temperatures and intense UV levels of summer can lead to inadequate protective measures.

All these groups should take special care to prevent UV injuries.

What to Do If You Develop Photokeratitis

“Like a sunburn on your skin, photokeratitis is not usually noticed until well after the damage has occurred” (Porter, 2024). If you experience eye discomfort such as pain, light sensitivity, tearing, or blurred vision after extensive exposure to high-intensity UV light, what should you do? You may have developed photokeratitis. Don’t worry. Seek medical attention promptly and have a professional ophthalmologist assess the extent of corneal damage. The doctor may prescribe antibiotic eye drops or ointment to prevent secondary infections. Generally, symptoms of photokeratitis will gradually improve within 24–48 hours. During recovery, it is important to wear protective sunglasses and minimize UV exposure. To prevent photokeratitis, proactive measures are important. When selecting protective sunglasses, choose glasses labeled with “100% UV Protection” or “UV400.”

Vision Aids for Low Vision Caused by UV Damage

In most cases, photokeratitis does not cause permanent vision loss, but severe or repeated UV damage can cause long-term effects on the cornea, leading to vision loss or visual impairment. If you already have low vision, don’t lose hope. Assistive technology can help you improve your life condition and enrich your visual experience.

Zoomax Snow Pad

  Snow Pad is a portable magnifier that connects to a tablet and has a dedicated app. With the tablet as a screen, it can simultaneously meet the needs of viewing near and distant objects through a split screen function. Both near and distant images are very clear. There is ample writing space below the tablet, enabling students and professionals to take notes in class or meetings. The dedicated app makes it possible to enhance the Snow Pad. Our ZOOMAX development team will add new functions and refine existing functions based on user feedback. Users will enjoy free app updates for life.

Zoomax Snow 12

Snow 12 is a portable magnifier designed to enhance your reading experience for books and digital content. Its large 12-inch screen offers broad vision, while the foldable stand provides ample space to place your hand and write. The combination of Snow 12 and the foldable stand makes extended reading and writing sessions more convenient. OCR/text-to-speech functions enable scanning and listening to books in various languages. Users can gain knowledge through both seeing and hearing.

Zoomax Luna 6

Luna 6 is a handheld magnifier that helps you identify various short texts and images in everyday life. Whether you are reading food ingredient labels while shopping, identifying appliance buttons at home, or checking bus stops outdoors, this magnifier can help you see more clearly. The built-in handle makes it easier to hold the magnifier when looking at distant objects. The wireless charging design offers convenience when you need to charge the magnifier.

Conclusion

Proper eye protection and avoiding prolonged exposure to intense UV rays can effectively prevent photokeratitis. To maintain eye health, prevention is as important as prompt treatment. This summer, make sure you not only enjoy your vacation but also stay healthy. Take good care of your eyes so you can continue to explore and appreciate the beauty of the world.

Reference

• Peralta, S. (2023). Photokeratitis. All About Vision. Retrieved July 29, 2025, from  https://www.allaboutvision.com/conditions/keratitis/photokeratitis/
• Blumthaler, M., Ambach, W., & Ellinger, R. (1997). Increase in solar UV radiation with altitude. Journal of Photochemistry and Photobiology B: Biology, 39(2), 130–134. https://doi.org/10.1016/S1011-1344(96)00018-8
• Porter, D. (2024). What is photokeratitis — Including snow blindness? American Academy of Ophthalmology. https://www.aao.org/eye-health/diseases/photokeratitis-snow-blindness