Measuring doseIonisation chamber

Ionization Chambers

Thimble chambers

600cc chamber

Determination of Absorbed dose • Absorbed dose to water

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• Corrections for Influence quantities

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Corrections

• Accurate dosimetry requires many small corrections

• E.G. Temperature/Pressure– Ionisation charge collected depends on amount of air in chamber– Correct by

• Other corrections for chamber characteristics– Recombination, polarity effects

• Complex business, keeps us in work!

293

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Pk PT

Medical Physics as a career

Training

• Minimum honours degree in physics

• Training process follows– Employed as “registrar” in a radiotherapy department

• Masters or Doctorate will be completed during this time• Five years hospital experience

– After five years, accreditation exams• Three hour written exam• Half day practical exam• Oral exam

• Most recover, with counselling!

Some of the staff

Physicist numbers

• There are 268 ROMPs in Australia employed at ~50 sites

• There is a mild shortage of ROMPs – 14% positions unfilled in Australia

– Many vacancies are filled from overseas

• Very international flavour to most departments

• Peter MacCallum Cancer Centre is one of Australia’s largest employers of ROMPs with 18 staff, including 3 registrars.

Other numbers!Salaries Vs Experience

0

20

40

60

80

100

120

0 5 10 15 20 25

Years experience

Sal

ary

$k

Others states do better …

• NSW has been much more effective at setting conditions• We want what they’ve got!

$40,000

$60,000

$80,000

$100,000

$120,000

$140,000

$160,000

$180,000

$200,000

MeS

3 (1

-2)

MeS

3 (3

)

MeS

4 (1

-2)

MeS

4 (3

)

MeS

4 (4

)

MeS

5 (1

)

MeS

5 (2

)

MeS

5 (3

)

MeS

5 (3

)

MeS

5 (3

)

MeS

5 (3

)

Relative to SA Medical Scientist MeS Levels (brackets indicate increments)

Rat

e o

f P

ay (

per

an

nu

m)

NSW Accrediated

NSW Non-Accrediated

SA with A&R Allowance

SA without A&R Allowance

Roles within Peter Mac • Radiation protection

– Targeting lowest possible occupational doses

• Dosimetry– Checking output against national laboratory standards

• Brachytherapy– Clinical work treating patients using radioactive sources

• Teaching/lecturing– Medical registrars

• Quality assurance– After hours work checking machine outputs and alignments

• Research– Many clinical projects trialling new approaches to treatment

• Development towards improved treatment– Application of new technology

Physicists at work

Physicists at work

Physicists at work

Working conditions:

So, what else do we do?

• About 50% (+/-30%!) of our time is unscheduled

• Most work is project based and open ended

• Most physicists have a specialty and pursue a project in that area

• My interest is in setup correction– Study of position accuracy for patients on treatment

– New imaging tools have become available

– New treatment techniques