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Ultraviolet (UV) light is divided into wavelength bands. UV-A is the 315-400nm.

The American Optometric Association claim that UV-A may cause injury to the eye:

WHAT PART OF THE UV RADIATION IS HARMFUL TO THE EYE?

Ultraviolet radiation in sunlight is commonly divided into two components: UV-B represents the short wavelength radiation (280 to 315 nanometers) that can cause sunburn and predispose to skin cancer, and the UV-A (315 to 400 nanometers) [...] UV-A radiation has lower energy, but penetrates much deeper into the eye and may also cause injury.

Prevent Blindness (a volunteer eye health and safety organization) claims:

UV-A can hurt your central vision. It can damage the macula, a part of the retina at the back of your eye.

While there's evidence that UV-B light may damage our vision, this question is specifically about UV-A light ranging from 315 to 400 nm.

A similar (but not identical) question has been asked here regarding the effects of blue light - which has a considerably higher wavelength than UV-A light. Most of the comments in that thread indicate that blue light does not cause harm. Additionally, the the top voted answer mostly addresses the fact that blue light blocks melatonin production which could fiddle around with the circadian rhythm. This primarily applies to light in the 470 - 525 nm range, not in other ranges.

Does UV-A light from sunlight, with a wavelength in the range of 315 - 400 nm, cause damage to the eyes of an otherwise healthy individual? Has this assumption been empirically tested and confirmed in humans?

  • Looks like this question may be a duplicate of this one which is also about sunglasses. – Laurel Nov 28 '18 at 3:30
  • Is your question about UV-A (okay) or is it about UV-B (okay) or is it about blue light (not notable and a duplicate) or is it about violet light (not notable)? – Oddthinking Nov 28 '18 at 5:17
  • Welcome to Skeptics! Is your question about UV-A (okay) or is it about UV-B (okay) or is it about blue light (not notable and a duplicate) or is it about violet light (not notable)? – Oddthinking Nov 28 '18 at 5:18
  • It seems it is about UV-A. Editing to make clear. – Oddthinking Nov 28 '18 at 5:19
  • The cornea and lens of the human eye blocks UVA which might suggest we have evolved to minimise the harm. The retina is sensitive to UVA and some people with artificial lenses can see UVA. – matt_black Nov 28 '18 at 10:14

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