Yep there have been a few people that have had to have eye surgery to remove debris and sand from there eyes after standing in the jet wake over the years, you would think they would learn as plenty of signs all over that state how dangerous it is but you do get idiots..
Yes I have stood behind jet engines before and felt the force of full thrust, but I would never stand on a sandy beach and do it, that is madness and asking for trouble, I know how painful it can be getting a few grains of sand in your eyes on the beach on a windy day let alone this..
Now if I took me brazing goggles with me that would be different