I took a trip with the family to a cave that I had been in two other times in my lifetime.

This was the very first time that I ever visited this cave with a geiger counter. I took in my Mazur 9000 pancake unit. It reached a high of 500 CPM during the tour.

In fact I did not have my geiger counter in a plastic bag during the 45 minute tour so it took over two hours after leaving the cave for the contamination to fully decay away. Then my unit returned to normal background readings. No change was seen when I was closer to the rock walls during the tour so I believe it is safe to assume the very high levels were caused due to radon gas. I had no idea the readings would be so high. I regret taking my family through there even as enjoyable as it was.

More information later...

So I'm guessing you are not convinced of the hormetic properties of radon?
rc

I'm right on the west coast... smokin hot in our drought stricken state when I'm out working in my garden, even before mid day when I've got to give up... sometimes that cool breeze will come in off the ocean... what a relief it used to be, until I've learned it's a fukushima breeze!

Yesterday there were actually a few raindrops from an overcast sky !
How can you not feel happy about that???
Washout.

It's a whole new ballgame, isn't it !

I have found information that proves that cave tour industry & OSHA are well aware of these high levels too. Unfortunately our young tour guide was completely unaware of radon or any other type of radiation he was being exposed to as a result of giving these tours all day. I told him what I could in the short time I had available.