Stay Safe During A Solar Eclipse
It is not safe to look at the sun without approved eye protection. Regular sunglasses will not protect your eyes.
Staring at the sun during a solar eclipse without protection may cause solar retinopathy, which is damage to your retina – the tissue at the back of your eye. Your retinas do not have pain sensors to signal damage from staring at the sun.
Symptoms may only surface 12 to 48 hours later, and may include:
- retinal burns
- temporary or permanent vision loss (immediate or delayed onset)
- blurred vision
Unfortunately, once symptoms start, it is usually too late to reverse any resulting damage.
If you begin to experience temporary visual loss, blurred vision, or eyesight loss during or after the event, speak to your eye care professional (e.g., optometrist) or your health care provider as soon as possible.
If you are experiencing blindness after viewing the eclipse (immediate or delayed), seek emergency care immediately. Do not drive.
How to Protect Your Eyes During a Solar Eclipse
Regular sunglasses will not protect your eyes.
It is dangerous to look directly at the sun any time – and especially during an eclipse. This can harm your eyes and even cause permanent damage and loss of sight.
To avoid eye damage during a solar eclipse:
It is not safe to view the eclipse through a camera, phone lens, telescope, binoculars, or any other optical device.
- It is not safe to look at the sun without approved eye protection. Regular sunglasses will not protect your eyes.
- Do not look at the sun at all. Looking at even a small sliver before or after the eclipse without protection can be harmful.
- Only use safe solar eclipse viewers or filters that meet international standard ISO 12312-2. They will make the sun look comfortably bright like the full moon.
- Indirect viewing methods, such as an eclipse box or a livestream, can also be used to experience an eclipse.
- Keep a close eye on children during a solar eclipse. Their eyes let in more light to the retina than adult eyes, so they are at higher risk of harm if they look at the sun without proper eye protection.
Tips when using eye protection:
- Only use filters or glasses that meet ISO 12312-2 international standards.
- Read and follow all directions.
- Check the viewer or filter for any damage, wrinkles, punctures or scratches before using it.
- Ensure the glasses fully cover your field of vision.
- Put on the glasses before looking at the solar eclipse and turn away from the eclipse before removing the glasses.
- Help children use their eye protection correctly. Children should always be supervised during eclipses as they may not fully understand the risks.
Additional resources:
- Toolkit for youth and educators for solar and lunar eclipses (Health Canada)
- Staying safe during solar eclipses (Canadian Space Agency)
- Solar eclipse vision safety (Canadian Association of Optometrists)
- Suppliers of safe solar filters and viewers (American Astronomical Society, endorsed by the Canadian Association of Optometrists)
Content on this page was adapted with permission from Toronto Public Health (2024).