Snow blindness - do people lose their goggles/glasses?

I’ve been watching Mount Everest documentaries and it seems like there are always people coming down the mountain with snow blindness.  (too much UV light in their eyes so it has temporarily burnedtheir retinas).  

One of the guys on the show said he had dropped his sunglasses and had only about 20 minutes of exposure without sunglasses at ~26k feet (8000m).  he was completely blind for days. The show narrator said that at these extreme altitudes that UV light is many times more intense than lower elevations.  

my question is, are all these people who are getting snow blindness dropping their sunglasses?  or is it a cumulative effect of brief moments of taking off their sunglasses/goggles?  (ie 2 min to apply sunscreen, 1 min cleaning lenses, etc).

I understand that none of us are probably not doing Mount Everest, but I’m just curious.

"One of the guys on the show said he had dropped his sunglasses.....he was completely blind for days.

Are people who are getting snow blindness dropping their sunglasses?"

Yes.

"a cumulative effect of brief moments of taking off their sunglasses/goggles?"

Possible. Depends.

Inadequate glasses also leads to snow blindness. 

BryanOC wrote:

..,I understand that none of us are probably not doing Mount Everest…

Wait.  Does this mean we’re ALL doing Everest?!

I better start training ;)

Unprotected eyes at upper elevations with or without snow are a sure way to do serious long-term damage to the eyes. All sunburn. Cover up.

Best to have wrap around sunglasses or goggles at altitude in the winter especially. Leave the skimpy fashion sunglasses at home. UV radiation reflects off the snow even if it is cloudy out and finds it's way into your eyes around smaller glasses or ones that fit further away from the face.

UV damage is cumulative like all radiation damage. A little here, a little there adds up to pain and loss of sight at the end of the day. Also, it is outside the visible spectrum so there is no indication one is being exposed until the cumulative amount gets too high.

Dispoable roll up sunglasses are a good idea for the first aid/repair kit in committing locations where snowblindness is a possibility:

https://www.walmart.com/ip/Roller-Shadz-Post-Mydriatic-Disposable-Roll-up-Sunglasses-3-pack/356403733

Last summer I was on a team of 4 climbing Mt. Baker (Washington) and on summit day, one of our team members took off his sunglasses as we climbed into cloudy, and then near whiteout conditions. He was without eye protection for at least 5 hours I'd say, at about 10,000 feet. Everything was fine until we turned in that evening back at camp and he suddenly started to have searing eye pain. He thought some dust had blown in his eyes - he said it felt like something gritty was in his eyes. We tried flushing his eyes with water several times, but it didn't much help. After a few hours we realized it was probably burnt retinas (snow blindness). That night was miserable for him. I don't think he slept at all. He was in severe, tear-inducing, whimpering pain continuously. We talked about packing up and hiking out that evening, but determined it would be safer to wait and do it in daylight. In the morning he was still in pain and his vision was blurry, but he was never 'blind'. We slowly and carefully made our way out in the morning and stopped at the first pharmacy we could. They had some over the counter stuff that provided some instant (though not total) relief. He followed up with an opthalmologist for some stronger stuff and just needed to wait it out for a few days - just like a sunburn. He was the first person I've ever personally known to suffer the unfortunate condition. I had always assumed snow blindness was a painless loss of vision. The reality was a good scared-straight lesson in remembering to always wear eye protection on snow. To lose total sight though? I imagine the damage would have to be more severe, and presumably more painful. Cover up!