-\validity of former assumptions so that more reliable calculations may be
made in shielding design.
The present work is concerned with the attenuation
characteristics of. a shield when the rays from the source enter fhe shield
obliquely.
To a first approximation, the effective thickness of the shield
_ has been assumed to be the length of path of the ray in the shiel id - that
is, the more oblique the direction of incidence, the longer the bath and
the greater the degree of shielding.
In this study it has been Bhown that
While oblique thickness of the barrier may be utilized in desig
g equip-
ment to shield against the primary rays, the contribution of sc
tered
radiation from within the shield may become appreciable. Scatt
ed radia-
tion increases significantly as the obliquity of the incident rdy increases,
because of the shorter path length for a number of the scattered rays.
Data obteined from these investigations will be applicable to the
design of protective shielding for personnel operating cyclotro S, Van de
Graaff generators, or handling Cobalt 60 and radium sources whi
th are used
in research and therzpy.
Radiation Instruments Program
(UNCLASST¥TED}
Recent work under the cooperative contract with the vow. Bureau of
otendards for stucies in the radiation instrument field includ
1.
Study cf Film Dosimeters.
A report has been completed
tion of the several types of film dosimeters in use at the vari
instailations.
on the evalug:
bus Corris S12 CTR
The work consisted of two carts:
E ARCHIVES