工業用X線の防護法

第3報: Stray Radiationについて

抄録

For the protection against X-rays, stray radiations are to be looked into: they are
(1) Off-focus radiation
(2) Forward-scattered radiation
(3) Back-scattered radiation
(4) Leaked radiation.
Screening of (1) is achieved by using the X-ray tube either with hooded anode and small slit or provided with a conical hood to limit the irradiation field.
Screening of (2) is by using a lead blind at the back of irradiated object.
The radiation (3) is effectively reduced either by making the field as small as possible and by using a filter appropriate to the working voltage and thickness of the object or by covering the object with metal such as Al, Fe, Ti or Pb. The latter utilizes the difference in quality and intensity of secondary X-rays by different materials.
To the screening of (4), the case of protection against direct beam described in the previous Report 2 is applied.