User manual

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APPENDIX B
An Efficient Protocol for Radiochromic Film Dosimetry
I. PURPOSE
To define a radiochromic film dosimetry protocol to measure radiation dose
distributions for comparison with a radiotherapy treatment plan.
II. SCOPE
The protocol applies to Gafchromic
™
EBT2 and EBT3 films exposed on a linear
accelerator. The object is to provide a time-efficient method for evaluating
radiotherapy treatment plans. It requires an unexposed calibration film, at least one
calibration film exposed to a known dose of radiation and the exposed application
film to be evaluated. It also requires the calibration film(s) and the application film to
be exposed within a time window. An explanation is given in Appendix C. The
application film is usually required for validation of a treatment plan and may be
exposed as a single treatment field, or as a composite of multiple treatment fields. In
either case it is assumed that the planned radiation dose distribution in the plane of
the exposed application film is known.
III. EQUIPMENT AND MATERIALS
 Gafchromic
™
EBT2 and EBT3 film
 Adhesive tape
 Phantom material to provide electron equilibrium, e.g. water equivalent plastic
blocks
 Linear Accelerator
 Treatment plan
 48-bit RGB Epson
®
flatbed scanner, preferably model 10000XL or 11000XL with
transparency adapter