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Your Local Civil Defense Guy
Radioactive consumer products turn up in surprising places.  We found two Radium dial clocks in our house (see analysis below).  A visit to the local thrift store turned up two more clocks.  Both of them were a contamination hazard.  The first had no crystal, so the clock was covered in Radium-Zinc Sulphide dust which is easily detected under UV light. The second had a crystal, but the dust had leaked out from behind the loose seal.  I sealed both clocks in zip lock bags and they now reside in my garage.

Another visit to the thrift store produced several radioactive plates.  These plates use uranium oxide glaze to produce a bright "uranium red" color.  The largest plate measured over 2 million counts per minute owing to its surface area (normal background radiation is around 45 CPM)!

Fortunately, uranium glazing is no longer used as a primary colorant in ceramic plates, tea cups, and saucers, but there are probably millions of pieces still out there.  Uranium and thorium continue to be used in some decorative glass and ceramics (even in some glass marbles), but the radiation levels are much lower. 

Laboratory and Field Equipment
(Aware Electronics RM-80 Radiation Monitor & LCD-90 Data Logger)
Real Time Data Analysis
(Aware Electronics Aw-Radw graphing software)
Personal Photo

Amazing Facts About Radioactivity (amazement guaranteed!)
Health Effects of Ionizing Radiation (Table)
A Note to Science Teachers
Estimating X-Ray and Gamma Ray Energy Levels with a Geiger Counter

Annotated graphs showing levels of radioactivity
(Data plotted with Aware Electronics AW-Graph and MakDecay)
How to Interpret these Graphs:  Assessing the Risk
Radioactivity in Cigarette Tobacco
Potassium-40 Series:  Salt Substitute, Kelp, Fertilizer, Glass
Thorium-232 Series:  Lantern Mantles, Thoriated Glass, Thoriated Welding Rods
Uranium-238 Series:  Pitchblende, Carnotite, Vaseline Glass
Americium-241 Series:  Smoke Detectors

Radium Clock Dial 
Radon Dust:  Decay Analysis
Cosmic Rays vs. Terrestrial Radiation
Bremsstrahlung:  Creating Soft-X-Rays from Beta Radiation
(Correction: While there is probably a small component of bremsstrahlung in these measurements, most of the increase is caused by the deflection of beta particles off the target through elastic collisions)