On Fri, 22 Apr 2005 01:03:47 +0100, Andy Dingley wrote:
On Thu, 21 Apr 2005 00:04:24 -0500, "Tim Williams"
wrote:

Actually, it is! As I recall, removed granite waste is a low-level
radiation "hazard".

I don't believe that for a moment.

Granite has sod-all radioactivity. Get a lump, try counting it - not
easy, even with good tools.

Hm. That's interesting, because I played with the Geiger counter last
night (technically a "Scintillation Meter"), and found the following:

Radiation survey of everyday objects:

Background radiation, 4 sites inside house: 1.5 Counts per Second (CPS)
Background radiation, 4 sites outside house: 1.5 CPS
4 over-ripe bananas, sensor in contact with skin: 3 CPS
Clean diapers: 1.5 CPS (no detectable radiation; same as background)
Dirty diapers, measured at top of diaper pail: 2 CPS
6 month old kid: 1.5 CPS plus drool and two giggles
"First Alert" smoke detector, with Americium goodness: 50 CPS on surface
10 year old Trijicon (Tritium) gunsights on Glock 19: 1.5 CPS
Granite boulder, roughly 1 meter in diameter. Pink: 4 CPS
Black: 3 CPS
Blue/black boulder of unknown ignious type: 1.5 CPS
Garden soil: 1.5 CPS

Obviously this is only a slightly scientific survey, but shows some
interesting non-background results.

The risk from granite is because it's found
in large underground masses and the daughter product is a gas. This can
travel, so if you have a house with a suitable basement and no
ventilation then you can be concentrating the radon from a huge quantity
of rock. If you live in a stone-built house on pillars though, no
hazard at all.

Right. Measurable doesn't mean dangerous. Well, except in the case of
the diaper pail above (trust me on this one). For the record, the kid just
started on bananas. I should check his other foods, just out of curiousity.

Dave Hinz