AbstractID: 8079 Title: Therapy Shielding
The application of the structural shielding design techniques and goals as outlined in NCRP Report 147: Structural Shielding Design
for Medical X-ray Imaging Facilities (November 2004) and NCRP Report 151: Structural Shielding Design and Evaluation for
Megavoltage X- and Gamma-Ray Radiotherapy Facilities will be the basis for this practical course. Actual facility designs will be
used as the example calculations of required shielding for Multi-Slice CT Simulators and Linear Accelerators to be installed in
modern radiation therapy facilities. Examples of methods to minimize the amount of additional shielding needed for new
departments due to well planned designs will be given.
As the equipment in radiation oncology departments has changed to CT simulators and linear accelerators with respiratory gating and
IMRT as state of the art modalities, the requirements for adequate radiation shielding for these modalities has become more rigorous.
Architectural designs no longer depend on standard maze design rectangular rooms. Innovative layouts and utilization of multiple
layers of shielding materials allow much greater flexibility in room designs. Shielding calculations for these challenging designs will
be covered in this presentation.
Educational Objectives:
1.
Understand the workload and occupancy factors to be used for multi-slice CT scanners and dual energy linear accelerators
with IMRT capability to determine required structural shielding to meet exposure limits for occupational personnel and
the public.
2.
Understand the effectiveness of existing and additional structural shielding materials to provide radiation protection and
methods to calculate the required amounts of these materials.
3.
Understand the calculation methods to be used in performing the shielding calculations of CT scanner and linear
accelerator installations to insure adequate shielding is provided to meet applicable state and ALARA requirements.