7D30.46 - Fluorescent Lights - Radioactive Starter Ballasts

Some compact fluorescent light bulbs have a starter ballast that contains a radioactive substance.
You can tell which bulbs contain the radioactive starters because they will flicker several times before they stay on.
You can cut apart the light bulb to expose the radioactive source.  In most cases this looks like a little glass container with two lead coming out of it.  In our case the radioactive substance is Krypton- 85.
The radioactivity can only be detected with a survey meter if the glass case is removed.
Code Number:
7D30.46
Demo Title:
Fluorescent Lights - Radioactive Starter Ballasts
Condition:
Excellent
Principle:
Particle Decay and Ionization
Area of Study:
Modern Physics
Equipment:
Compact Fluorescent Lights, Radiation Counter if Desired.
Procedure:

Some compact fluorescent light bulbs have a starter ballast that contains a radioactive substance.  You can tell which bulbs contain the radioactive starters because they will flicker several times before they stay on.  

You can cut apart the light bulb to expose the radioactive source.  In most cases this looks like a little glass container with two lead coming out of it.  In our case the radioactive substance is Krypton- 85.  The radioactivity can only be detected with a survey meter if the glass case is removed. 

References:
  • Chris Smolinski, "Radioactive Products and Other Sources Of Radiation".

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