Biomedical Engineering Reference
In-Depth Information
If the radon concentration (
222
Rn) inside a building is
0.85 pCi L
-1
and the equilibrium factor is 0.6, what is the rate of
release of alpha-particle energy in MeV L
-1
h
-1
?
34.
35.
Show that
(a)
1WL
= 2.1 × 10
-5
Jm
-3
1WLM
= 0.0036
Jhm
-3
.
(b)
36.
A 3-L air sample contains the following radon-daughter
activities:
218
Po, 16.2 Bq;
214
Pb, 15.0 Bq;
214
Bi, 12.2 Bq; and
214
Po, 12.2 Bq. Calculate the WL concentration.
37.
A person spends an average of 10 hours per day, 5 days per
week, in an atmosphere where the average radon-daughter
concentration is 0.68 WL. What is his exposure in WLM after
one year of this activity?
38.
A basement measures 12 m
2.5 m. The air inside
contains the nuclide inventory shown in Table 4.6.
(a)
×
10 m
×
Calculate the WL concentration.
(b)
If the given activities are average and a person occupies the
basement 10 hours per day, 7 days per week, for
12 months, what will be his exposure in WLM?
Tab l e 4 . 6
Problem 38
Activity
Nuclide
(
µ
Ci)
222
Rn
0.81
218
Po
0.69
214
Pb
0.44
214
Bi
0.25
214
Po
0.25
3m
. It contains 80 pCi L
-1
of
218
Po,60pCiL
-1
of
214
Pb, and 25 pCi L
-1
each of
214
Bi
and
214
Po.
(a)
39.
A room measures
10 m
×
8m
×
Calculate the WL concentration in the room.
(b)
Calculate the total potential alpha-particle energy in the
room.
What is the concentration of
214
Po atoms in the air?
(c)
(d)
If secular equilibrium existed at this working-level
concentration, what would be the activity concentration of
214
Pb atoms?
(e)
What would be the exposure in WLM of an individual who
occupied the room 12 hours per day, 6 days per week, for
one year?
