2.3 Maximum permissible dose (MPD)
Before operation, persons qualified and authorized to operate this equipment should
be familiar with the recommendations of the international commission on radiological
protection, contained in annals number 60 of the icrp, with applicable national standards;
and should have been trained in use of the equipment.
WARNING： The operator shall use the largest possible focal spot to skin
distance in order to keep the absorbed dose also was reasonably achievable.
2.4 Radiation protection
Because exposure to x-ray radiation can be damaging to the health, use great care to
ensure protection against exposure to the primary beam. Some of the effects of x-ray
radiation are cumulative and may extend over a period of months or years. The best safety
rule for an x-ray operator is “avoid exposure to the primary beam at all times”.
Any object in the path of the primary beam produces secondary (scattered) radiation.
The intensity of secondary radiation depends on the energy and intensity of the primary
beam and the atomic number of the object material struck by the primary beam. Secondary
radiation may be of greater intensity than that of the radiation reaching the film. Take
protective measures to safeguard against this.
An effective protective measure is the use of lead shielding. To minimize dangerous
exposure, use such items as lead screens, lead impregnated gloves, aprons, thyroid collars,
etc. Lead screens should contain a minimum of 2.0 mm of lead or equivalent and personal
protective devices (aprons, gloves, etc.) Must contain a minimum of 0.25 mm of lead or
equivalent. For confirmation of the local requirements at your site, please refer to your
“local radiation protection rules” as provided by your radiation protection advisor.
WARNING: While operating or servicing x-ray equipment, always keep a
distance of not less than 2 meters from the focal spot and x-ray beam, protect
body and do not expose hands, wrists, arms or other parts of the body to the
primary beam.
2.5 Monitoring of Personnel
Monitoring personnel to determine the amount of radiation to which they have been
exposed provides a valuable cross check to determine whether or not safety measures are
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