Other uses of plutonium - HDBK-1145-2001new0109

Radiological Safety Training for Plutonium Facilities

DOEHDBK11452001

Student's Guide

The actual nuclide and quantity produced depend

on the source material, type of reactor, and length of

irradiation time.

The reactor grade, with its higher Pu-240 content,

presents a much higher gamma and neutron dose rate

than does the weapons grade. The reason is that the

Pu-240 has more than 1000 times the spontaneous

fission rate than does the Pu-239. Pu-241 and Pu-242

also have a much higher spontaneous fission rate.

The prompt gammas and neutrons from the

spontaneous fission and the fission product gammas

produce a much higher overall dose rate for the

reactor grade material.

Table 1 shows the approximate weight

percentages of the three grades of plutonium.

In November 1946, the first nuclear reactor to use

separated out plutonium as fuel, called Clementine,

was activated at Los Alamos. Since more plutonium

can be bred during the operation of the reactor, the

country's nuclear fuel reserves could be greatly

increased as a result.

Table 1

Approximate Weight Percentages of Predominant Nuclides

Nuclide

Heat-Source

Weapons Grade

Reactor Grade

Pu-238

90.0

<0.05

1.5

9.1

93.6

58.1

Pu-239

24.1

Pu-240

0.6

6.0

0.4

11.4

Pu-241

0.03

<0.05

4.9

Pu-242

<0.01

D. Other uses of plutonium

Plutonium can also be used in neutron detectors

and neutron sources, as well as in the production of

other man-made elements.