In article , Jim McLaughlin
wrote:

There have been a couple of incidents around here (Portland / Lake Oswego,
OR) recently where Halide lights in school gymnasiums (ok gymnasia to the
Latin /reek scholars) had cracked outer coatings. The lights emitted
a_LOT_ of bad UV stuff; several students and teachers apparently suffered
serious and permanent eye damage. The exposure was over a several month
period, AIUI, and there was no obvious indicator that the bulb outer
coatings were cracked.

I believe the degree of eye damage was overblown. If the bulb has just
a crack, not much nasty UV gets out. And the way I hear it, eye
irritation from shortwave UV and UVB is generally recoverable.

But if the bulbs are in an enclosed fixture, then the fixture covering
stops any nast UV that gets out of the bulb.

- Don Klipstein )