P32 shielding
Meredith Gould (mgould@bahia.ens.uabc.mx)
Fri, 23 Jan 1998 13:18:10 -0800
Christof Turck wrote asking for advice about shielding P32 radiation.
Usually plastic (e.g. 3/4 inch plexiglas) is used since collision of the
beta particles with nuclei of atoms of low atomic number produces less X-ray
emission (bremsstrahlung) than with heavy nuclei like lead. However, we have
observed that even with plastic there is a significant amount of X-ray
emission (detectable with a gamma dosimeter) if the source is very
radioactive. Therefore we bought a lead-impregnated plastic shield from
Nuclear Associates (a division of Victoreen, 100 Voice Rd., PO 349, Carle
Place NY 11514-0349), which completely absorbs both P32 and X & gamma rays.
It is a portable transparent bench top shield that comes in various sizes.
We use it for manipulations. For shielding wastes, stock solutions, etc. in
the work area we built a "box" with 3/4 in plastic then put lead sheeting
outside. The box has a floor and lid of the same construction to protect
feet and face. We use thick lead because we also work with gamma emitters,
however, for P32 lead foil is adequate. The plastic absorbs the beta then
the lead absorbs the X and gamma. For storage in areas where no one is
exposed, we use just plastic.
Dr. Meredith Gould
Facultad de Ciencias
Universidad Autonoma de Baja California
A.P. 2921, Ensenada 22800, B.C. Mexico
tel/fax 011-52-61-744-560
mgould@bahia.ens.uabc.mx