Millions across North America prepare to watch the total solar eclipse, the rare occurrence when the moon passes in between Earth and the Sun, casting its shadow on Earth, on Monday. Here are a few tips to protect your eyes from permanent damage while viewing the phenomenon | NASA

Eye safety is a top priority to avoid permanent damage caused by solar retinopathy | Reuters

Eclipse glasses should have a special ISO filter (ISO 12312-2 standard limit) to prevent harmful ultraviolet and infrared light from affecting the retina | AP

Do not look at the sun without proper eye protection, even during eclipses. Reminiscent of cardboard 3D viewing glasses, eclipse glasses are essential for protecting your eyes while viewing a solar eclipse | AP

If you plan to take pictures of the eclipse or view it through any type of lens, such as a telescope or binoculars, you should cover the lens with a special solar filter to avoid eye injury | Reuters

Sunglasses or homemade eclipse glasses do not provide sufficient protection | Reuters

Solar retinopathy

It develops when the retina becomes damaged by exposure to solar radiation. Symptoms of damage include blurred vision, increased light sensitivity, central blind spots in either or both eyes and distortions | Reuters

If you are spending more than a few minutes outside, you should also wear sunscreen and sun-protective clothing | Reuters