EFFECTS OF RADIATION
DOE-HDBK-1015/2-93
Reactor Water Chemistry
ON WATER CHEMISTRY (SYNTHESIS)
CH-03
Rev. 0
Page 10
Two other nuclear reactions with oxygen isotopes are shown below.
O (p, n) F (t
= 112 minutes)
18
18
8
9
1/2
O (p, ) N (t
= 10 minutes)
16
13
8
7
1/2
An ejected alpha particle is indicated by . The protons that cause these reactions result from
inelastic collisions of fast neutrons with hydrogen atoms in water molecules. The radioactivity
levels of these isotopes are much lower than the levels of N and N during reactor facility
16
17
7
7
operation. However, during the period from a few minutes to about five hours after reactor
shutdown or after removing a coolant sample from the system, N and F are the principal
13
18
7
9
sources of radioactivity in the reactor coolant of most reactor facilities.
N C +
13
13
0
7
6
+1
F O +
18
18
0
9
8
+1
The only significant nuclear reaction that occurs with hydrogen involves deuterium ( H), which
2
1
comprises about 0.015 percent of natural hydrogen.
H (n, ) H (t
= 12.3 years)
2
3
1
1
1/2
Tritium ( H) decays by emission of a very weak particle (0.02 Mev) and no gamma rays.
3
1
Thus, tritium is not a radiological hazard unless it enters the body in significant amounts.
Tritium can enter the body through inhalation or ingestion. It is also possible to absorb forms
of tritium through the skin.
