Re: Thanks for the data. Here is some additional data and perspective.February 10 2011 at 6:10 PM
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Response to Thanks for the data. Here is some additional data and perspective.
Not necessarily so, I am afraid. Photon radiation only follows the inverse square law when the distance it is being measured is at least 1/2 of the source diameter. As an example, if the source was 10 mm in diameter, the inverse square principal only comes into play outside of 5 mm distance away. Anything closer, and the photon decreases at an inversly proportional level (the distances in the equation are not squared).
As an example, supppose one had a dial reading 10mr/hr @ 1 mm. At 5mm it would be reading 2mr/hr.
If one used the inverse square principal (incorrectly) in this scenario, the 5 mm reading would be .4 mr/hr.
Also, as the watch movement and case is of a metal composition, which is denser than the crystal, less radiation would be found on the side of the watch that most folks place on the skin.
But, agreed that the real hazard is when one has a cracked/broken crystal, or does take it apart to work on it. The alpha radiation from the Ra 226 is what to worry about.