910
J. cl. Reissland et al.
force but with no mitial exposure and no ex-workers with radiation exposure.
‘The steady state exposure pattern and ex-worker distribution is built wp by
calculating the annual number of radiation deaths for each year up to 50 years.
The results are summarized in fig. 3 and table 4.
1-0
a
oe AM
eg
0-8
_
x13
zl
/. ae
0-6
i
ME
[4i/
0-4
of
0
Wig. 3.
[er
oo
af
if /
5
0
1
The growth to steady state.
20
25
30
35
40
4&5
56
Time ,/ lyears)
Curve I represents the growth of the number of
ex-workers with radiation exposure. Curve Il is the growth of the expected
miumber of radiation-induced cancer deaths among in-service workers and curve I]
mmonge ox-workers. N(é) is the nuniber in year é and N (co) the mamberin tho steady
stale as in tablo 2, coluinn A.
‘Table 4. Showing the accumulated numberof radiation-induced deaths in 5-year
intervals following time zcro when radiation exposure becan. Also shownis the
number of people involved for our standard 100000 workers exposed to 1 rad}
year cach and for 3000 workers exposed to $radfycar cach
Time (years)
10
15
20
25
30
159 $61
175 749
197 543
216 279
231 905
Lb
7
35
47
103
4526
5272
5 926
G 488
G 957
0-06
0-235
0-57
1-0
1-5
Working population 100 000
(1 rad/year)
Volal workers
IM -|- eX
Accuinulated tu
deaths Agg
Working population 3000
(4 vrad/ycar)
‘Ratal workers
IN + EN
Aecumulated rt
deaths Ay
3.
Observation time
‘3.1. Pane required for a survey
We are interested in an estimate of the number of years over which cancer
deaths among radiation workers must be observed to show a significant
difference between them and a corresponding group of non-radiation workers.