Beware of your dive light!!
Dive lights and video lights are a lot brighter and therefore
can be much hotter than an average household flashlight. Some
manufactures of dive lights even say they should be used only
underwater. The reason being that the water keeps them cooler.
In other words, dive lights get hot, real hot. I mean really hot.
The first time I saw how hot this could be was when a diver
was carrying a bag onto an airplane. Halfway to the steps, the
bag was smoldering! In it was a very powerful European made dive
light. If you have never seen one of these, they look like something
made to carry plutonium. When he opened his case the inside of
the bag was more or less a melted pile of plastics and other unrecognizable
items. The light had only been on a few minutes! Imagine if this
had been in the cargo space and happened after the plane took
off with no one around to see it?
The other time was just a small dive light that was in checked
on baggage. When the diver opened his suitcase the next day, the
little yellow light, which previously had a rather flat plastic
lens, now had a very domed plastic lens and very dead batteries.
The picture of this is below. The heat was so intense, and with
the lower airplane pressure, it caused the plastic to bulge out
and discolor. Had something been close by with a low flash point,
a fire could have easily started. One doesn't need much imagination
to think what the result of that could have been. Also the light
was packed with the switch in the locked position! So much for
locks on the switches.
Don' t ever travel with batteries in your lights. Don't trust
the locks on the switches either. And if you feel you absolutely
need to keep the batteries in the light because of space (a poor
excuse though), at least remove the bulb or one battery.
What used to be a flat lens is now a domed lens.