electrons from medical x-ray equipment

["Randy Ross" <RNROSS@BCSC02.GOV.BC.CA>]

To: RADSAFE --INTERNET RADSAFE@ROMULUS.EH AHGOOD  --BCSC02   Alan Good
    FRANSELM--BCSC02   Francine Anselmo


I just can across an article that discusses the use of collimation in medical
x-ray. It says "It must be noted that numerous electrons are produced be the
interaction of photons with the collimator. In order to prevent these
electrons from reaching the patient the collimator position should be at least
15 cm above the patient's skin. If the photon beam contains a large number of
electrons, the energy absorbed by the skin is greatly increased and may result
in severe skin reactions."

I have not heard that this is as significant a situation as the author
above describes.  Does anyone know more about this?      (Thanks in advance,
as they say) - Randy

Radiation Protection, Ministry of Health, British Columbia
The opinions and material above are solely those of the author.
This is a disclaimer for postings to bulletin boards, newsgroups
etc., on the internet.  Randy Ross, rnross@bcsc02.gov.bc.ca