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Re: X-Ray Vision Is Here



GEORGE CICOTTE wrote:
> 
>      Anyone want to bet the "3 microREMs" that NIS advertises is over a
>      short (far less than 1 s ) period of time?  The 6 to 10 micro-r that
>      constitutes a typical background wouldn't contribute a significant
>      photon fluence for that picture.
> 
>      What seems rather interesting is to see dose described as an emission,
>      and 36 micro-r per hour (3 x 60 min/h / 5 min) as a typical exposure
>      rate for naturally occurring background environmental radioactivity.
>      One wonders who their health physicists are.  Are they perhaps located
>      over the Reading Prong, or do they simply have a really poorly
>      ventilated home in Colorado?
> 

Hi George and Radsafers,

The average US natural background dose rate is 400 mrem/y (30 cosmic, 25
external gamma, 30 internal K-40, and 300 radon). This works out to 45
microrem/h TEDE or 3.8 microrem per 5 min. If you believe that Effective
Dose Equivalent is proportional to risk (cancer), than it makes sence to
equate a 3 microrem EDE from this machine to about 5 min of natural EDE.
Both SHOULD have the same radiation risk, according to current
mainstream radiation protection theory.

Bset Regards,
Wes
-- 
Wesley R. Van Pelt, Ph.D., CIH, CHP                KF2LG
President, Van Pelt Associates, Inc.     
Consulting in radiological health and safety.
mailto:VanPeltW@IDT.net        
http://shell.idt.net/~vanpeltw/index.html