radioprotection of staff in nuclear medicine - bvsabr.be · bvs/abr 20-6-2008 keeping the doses low...

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


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


1965

Since

Introduction

DOSIMETRY?DOSIMETRY?FilmFilm TldTld↓↓ ↓↓

image + doseimage + dose dosedose

223

3 1

1 15 56 6

4 4

7


1965

Since

IntroductionElectronic dosemeter (EPD)Electronic dosemeter (EPD)

TeachingTeachingReflectionReflection

AwarenessAwareness


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


1965

Since








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


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


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


1965

Since








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


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)


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)


1965

Since








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


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


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


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)


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


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


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


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)


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


1965

Since








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


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


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)



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



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



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



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



1965

Since








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


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


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)


1965

Since

Thanks to

•• Health CouncilHealth Council

•• FranFranççois ois JamarJamar

•• Peter CovensPeter Covens

•• Belgian Society of Nuclear MedicineBelgian Society of Nuclear Medicine

radioprotection of staff in nuclear medicine - bvsabr.be · bvs/abr 20-6-2008 keeping the doses low...

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