

DOESTD112898
fi
= the weight fraction of the ith isotope of plutonium
t
= the time since chemical separation of the plutonium, days.
This equation is only valid for a year or so after chemical separation,
when the ingrowth of 241Am can be represented linearly.
A similar equation has been derived for leadloaded rubber gloves using
the calculations from the computer code PUSHLD. The 80mil lead
loaded glove is nominally 1.9mm (0.076in.) thick in the palm and
forearm and contains the equivalent of about 1 mm of lead. The surface
dose rate, DPbGl, is given by the following equation:
DPbGl(t) = 2.83 f238 e0.00789t + 0.104 f239 + 0.0315 f240
(6.3)
+ 6.35 x 105 f242 + f241 (158.5 e0.0016t  152.5 e0.0457t)
where DpbGl(t) = surface dose rate as a function of time, rad/h
fi
= weight fraction of the ith plutonium isotope
t
= time since chemical separation of the plutonium, years.
times between 50 days and 100 years after the chemical separation of the
plutonium. The formula predicts dose rates from 0% to +20% of those
calculated by the computer code PUSHLD.
6.2.3
Neutron Dose Equivalents
Neutron dose equivalents are significant in any process or decommissioning
efforts involving kilogram quantities of plutonium or gram quantities of 238Pu.
Neutrons originate from three sources:
 Spontaneous fission of even isotopes of plutonium
 alphaneutron reactions with lowatomicnumber elements, including oxygen
and fluorine in plutonium compounds and impurities in metals
 neutroninduced fissions.
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