Significance and Use 4.1 The design and operation of a self-
contained irradiator should ensure that reproducible absorbed
doses are obtained when the same irradiation parameters are
used. Dosimetry is performed to determine the relationship
between the irradiation parameters and the absorbed dose. 4.1.1
For most applications, the absorbed dose is expressed as
absorbed dose to water (see ISO/ASTM Practice 51261). For
conversion of absorbed dose to water to that to other materials,
for example, silicon, see Annex A1 of ISO/ASTM Practice 51261.
4.2 Self-contained dry-storage gamma irradiators contain
properly shielded radioactive sources, namely 137Cs or 60Co,
that emit ionizing electromagnetic radiation (gamma radiation).
These irradiators have an enclosed, accessible irradiator sample
chamber connected with a sample positioning system, for example,
irradiator drawer, rotor, or irradiator turntable, as part of
the irradiation device. 4.3 Self-contained dry-storage gamma
irradiators can be used for many radiatio