Why is it suggested to wear dark coloured goggles while watching magnesium burn in air?

Wearing dark-colored goggles while watching magnesium burn in air is suggested because the intense light produced during the combustion can be extremely bright and harmful to the eyes. Magnesium burns emit ultraviolet (UV) light and intense glare, which can cause eye damage or discomfort. Dark goggles help filter out this harmful brightness and protect the viewer's vision. Additionally, they may reduce the risk of photokeratitis, a painful condition similar to sunburn of the cornea.