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BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 1
1965
Since
Radioprotection of staff in nuclear medicine
E. De GeestE. De GeestAV Controlatom, Vilvoorde, BelgiumAV Controlatom, Vilvoorde, Belgium
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 2
1965
Since
Overview•• IntroductionIntroduction
•• Situation of NM in the total dose distribution of Situation of NM in the total dose distribution of nuclear workersnuclear workers
•• Study in nuclear medicine (1998 Study in nuclear medicine (1998 –– 2000)2000)
•• Study 2003Study 2003--2005 (Dose determining parameters)2005 (Dose determining parameters)
•• PET study of Health Council (2002PET study of Health Council (2002--2004)2004)
•• ConclusionConclusion
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 3
1965
Since
Introduction
DOSIMETRY?DOSIMETRY?FilmFilm TldTld↓↓ ↓↓
image + doseimage + dose dosedose
223
3 1
1 15 56 6
4 4
7
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 4
1965
Since
IntroductionElectronic dosemeter (EPD)Electronic dosemeter (EPD)
TeachingTeachingReflectionReflection
AwarenessAwareness
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 5
1965
Since
Introduction
Dosimetry to evaluateDosimetry to evaluate
•• Dose limitsDose limits•• OptimisationOptimisation•• Radioprotection measuresRadioprotection measures•• Your own dose Your own dose ‘‘in competitionin competition’’ with with
peerspeers
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 6
1965
Since
Overview•• IntroductionIntroduction
•• Situation of NM in the total dose distribution of Situation of NM in the total dose distribution of nuclear workersnuclear workers
•• Study in nuclear medicine (1998 Study in nuclear medicine (1998 –– 2000)2000)
•• Study 2003Study 2003--2005 (Dose determining parameters)2005 (Dose determining parameters)
•• PET study of Health Council (2002PET study of Health Council (2002--2004)2004)
•• ConclusionConclusion
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 7
1965
Since
Evolution of 12M dosis of nuclear workers in Belgium
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
<0.01 <2 <5 <10 <15 <20 <30 <40 <50 >50
Dose (mSv)
Perc
enta
ge
1992 1993 1994
1995 1996 1997
1998 1999 2000
2001 2002 2003
2004
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 8
1965
Since
Dose distribution of nuclear workers in Belgium
0.00
20.00
40.00
60.00
80.00
100.00
120.00
0 <2 <5 <10 <15 <20 <30 <40 <50 >50
Dose (mSv)
% o
f wor
kers
Medical Sector
Industrial Sector
Education and Research
Total
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 9
1965
Since
Dose distribution of nuclear workers in a hospital
0
200
400
600
800
1000
1200
Cardio
Dagkli
niek
Gastro
HartCath
.
NGTec
hn. Dien
stOnderh
oud OK
Pneumo RT RX
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 10
1965
Since
Overview•• IntroductionIntroduction
•• Situation of NM in the total dose distribution of Situation of NM in the total dose distribution of nuclear workersnuclear workers
•• Study in nuclear medicine (1998 Study in nuclear medicine (1998 –– 2000)2000)
•• Study 2003Study 2003--2005 (Dose determining parameters)2005 (Dose determining parameters)
•• PET study of Health Council (2002PET study of Health Council (2002--2004)2004)
•• ConclusionConclusion
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 11
1965
Since
Study 1998 - 2000
•• In house study of dosimetry without In house study of dosimetry without consultation of the field (20 NM departments)consultation of the field (20 NM departments)
•• Inaccuraccy : no data about working hoursInaccuraccy : no data about working hours
RESULTSRESULTS•• No significant difference in average doses over No significant difference in average doses over
the years 1998 the years 1998 ––2000 (< 20% variation)2000 (< 20% variation)•• Highest doses on the group of technologistsHighest doses on the group of technologists
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 12
1965
Since
Average dose in functionof time
3000
3200
3400
3600
3800
4000
4200
4400
4600
Average 2000 Average 1999 Average 1998
Dos
e (µ
Sv)
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 13
1965
Since
Average dose in functionof activity
0
1000
2000
3000
4000
5000
6000
Physician In Vitro Lab Technologist
Ave
rage
dos
e (µ
Sv)
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 14
1965
Since
Overview•• IntroductionIntroduction
•• Situation of NM in the total dose distribution of Situation of NM in the total dose distribution of nuclear workersnuclear workers
•• Study in nuclear medicine (1998 Study in nuclear medicine (1998 –– 2000)2000)
•• Study 2003Study 2003--2005 (Dose determining parameters)2005 (Dose determining parameters)
•• PET study of Health Council (2002PET study of Health Council (2002--2004)2004)
•• ConclusionConclusion
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 15
1965
Since
Study 2003-2005
•• 15 NM departments 15 NM departments (1500 (1500 -- 6000 patients/year)6000 patients/year)
•• 38 Technologists38 Technologists
•• In depth evaluation on site by a health In depth evaluation on site by a health physicistphysicist•• Department characteristicsDepartment characteristics•• Personnel characteristicsPersonnel characteristics
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 16
1965
Since
Results
•• Average dose of a technologist normalised for Average dose of a technologist normalised for Full Time Equivalent (FTE)Full Time Equivalent (FTE)
•• 50% doses less than 5 mSv/y (FTE)50% doses less than 5 mSv/y (FTE)•• Minimum : 1.22 mSv/yMinimum : 1.22 mSv/y•• Maximum : 14.43 mSv/yMaximum : 14.43 mSv/y
5.96 mSv5.96 mSv6.62 mSv6.62 mSv6.32 mSv6.32 mSv
200520052004200420032003
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 17
1965
Since
Results
•• Individual dose (FTE) per # patients per Individual dose (FTE) per # patients per FTEFTE
My dose is 3 mSv (12M), I work 4/5, we My dose is 3 mSv (12M), I work 4/5, we do 2500 patients per year and I have a do 2500 patients per year and I have a colleague that works full time.colleague that works full time.
3 * 5/4 * 1/2500 *1.8 = 2.7 3 * 5/4 * 1/2500 *1.8 = 2.7 µµSvSv
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 18
1965
Since
Seniority, working regime
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
40.00
45.00
50.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Technologists
Seni
ority
(yea
rs),
Wor
king
hou
rs/w
eek
(h)
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
Indi
vidu
al d
ose
(FTE
) per
#pa
tient
s pe
r FTE
(µ
Sv)
Working hours/week
Seniority
Normalised individual doses (FTE, p)
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 19
1965
Since Attitude
0
1
2
3
4
5
6
7
8
social behavior syringe protection Lead apron
Indi
vidu
al d
ose
(FTE
) per
#pa
tient
s pe
r FT
E) (µ
Sv)
AlwaysSometimesNever
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 20
1965
Since
Results
•• Collective dose per # patientsCollective dose per # patients
My dose is 3 mSv (12M), (I work 4/5), My dose is 3 mSv (12M), (I work 4/5), we do 2500 patients per year and I have a we do 2500 patients per year and I have a colleague (that works full time) and her colleague (that works full time) and her doses is also 3 mSv (12M).doses is also 3 mSv (12M).
(3 + 3) / 2500 = 2.3 (3 + 3) / 2500 = 2.3 µµSvSv
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 21
1965
Since
Size hotlab and cameraroom
0.00
1.00
2.00
3.00
4.00
5.00
6.00
Small Medium Large
Col
lect
ive
dose
/ # p
atie
nts
(µSv
)
Size hotlab Size Cameraroom
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 22
1965
Since
Overall impression (scored on 5)
0
1
2
3
4
5
6
7
8
9
10
N E C O D K B F A I J H G L MDepartment
Scor
e on
5 p
oint
Clean?
Neat?
Organisation?
Collective dose / # patients (µSv)
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 23
1965
Since
Influence of radionuclide therapy
0
1
2
3
4
5
6
7
8
9
10
N E C O D K B F A I J H G L M
Col
lect
ive
dose
/ #
patie
nts
(µSv
)
0
20
40
60
80
100
120
140
160
# th
erap
y pa
tient
s
Collect. Dose / # patients
Nr. of therapy patients
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 24
1965
Since
Overview•• IntroductionIntroduction
•• Situation of NM in the total dose distribution of Situation of NM in the total dose distribution of nuclear workersnuclear workers
•• Study in nuclear medicine (1998 Study in nuclear medicine (1998 –– 2000)2000)
•• Study 2003Study 2003--2005 (Dose determining parameters)2005 (Dose determining parameters)
•• PET study of Health Council (2002PET study of Health Council (2002--2004)2004)
•• ConclusionConclusion
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 25
1965
Since
PET study
•• Evaluation of the influence of PET on the Evaluation of the influence of PET on the occupational dose radiation workers.occupational dose radiation workers.Do we need to provide guidelines?Do we need to provide guidelines?
•• Inaccuracy: not fully completed forms Inaccuracy: not fully completed forms
•• 20022002--20042004•• 8 PET/SPECT (61 technologists) 8 PET/SPECT (61 technologists) av. 700 bedsav. 700 beds
13 SPECT (44 technologists) 13 SPECT (44 technologists) av. 400 bedsav. 400 beds
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 26
1965
Since
FTE Hp(10) (mSv/y)
0
5
10
15
20
25
2004 2003 2002
FTE
Hp(
10) (
mSv
//j)
TOTAL PET/SPECT SPECT
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 27
1965
Since
Hp(10)/examination (µSv)
0
2
4
6
8
10
12
14
16
18
2004 2003 2002
Indi
vidu
al H
p(10
)/exa
min
atio
n (µ
Sv)
TOTAL PET/SPECT SPECT
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 28
1965
Since
Work in hotlab?
0
2
4
6
8
10
12
14
16
Indi
vidu
al H
p(10
)/exa
min
atio
n (µ
Sv)
Y N Y N Y N
TOTAL PET/SPECT SPECT
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 29
1965
Since
Injection of patients?
0
2
4
6
8
10
12
14
16
Indi
vidu
al H
p(10
)/exa
min
atio
n (µ
Sv)
Y N Y N Y N
TOTAL PET/SPECT SPECT
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 30
1965
Since
Use of syringe protection?
0
2
4
6
8
10
12
14
16
Indi
vidu
al H
p(10
)/exa
min
atio
n (µ
Sv)
Always Rare Always Rare Always Rare
TOTAL PET/SPECT SPECT
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 31
1965
Since
Use of lead apron?
95% rare/never 95% rare/never poor datapoor data
0
2
4
6
8
10
12
14
16
Indi
vidu
al H
p(10
)/exa
min
atio
n (µ
Sv)
Often Rare Often Rare Often Rare
TOTAL PET/SPECT SPECT
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 32
1965
Since
Overview•• IntroductionIntroduction
•• Situation of NM in the total dose distribution of Situation of NM in the total dose distribution of nuclear workersnuclear workers
•• Study in nuclear medicine (1998 Study in nuclear medicine (1998 –– 2000)2000)
•• Study 2003Study 2003--2005 (Dose determining parameters)2005 (Dose determining parameters)
•• PET study of Health Council (2002PET study of Health Council (2002--2004)2004)
•• ConclusionConclusion
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 33
1965
Since
Conclusions
•• Important parameters: Important parameters:
•• Attitude of workerAttitude of worker
•• Adapted department (design,Adapted department (design,……))
•• Keep it neat and well organisedKeep it neat and well organised
•• Seniority Seniority –– working regimeworking regime
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 34
1965
Since
Conclusions
•• PET/SPECT PET/SPECT ≈≈ SPECTSPECT
↑↑ per examinationper examination
↓↓ number of examinationsnumber of examinations
•• More important to follow RP rulesMore important to follow RP rules
BVS/ABR 20-6-2008 Keeping the doses low by setting the standards high 35
1965
Since
Conclusions
•• Statistic tools on dosimetry shows trends Statistic tools on dosimetry shows trends and can reveal dose determining parametersand can reveal dose determining parameters
Lack of central database!Lack of central database!
•• Dosimetry is an instrument in health Dosimetry is an instrument in health physics for continuous reduction of physics for continuous reduction of individualindividual doses (ALARA)doses (ALARA)