Low cost CCD camera protection against neutron radiation damage

Area of Science:

• Medical Physics
• Radiation Oncology
• Materials Science

Background:

• Linear accelerators (linacs) used in radiotherapy produce high-energy electron and photon beams for cancer treatment.
• Closed-circuit television (CCTV) systems with charge-coupled device (CCD) cameras monitor patients during radiotherapy.
• Neutron radiation, a byproduct of linac operation, can damage sensitive CCD cameras over time.

Purpose of the Study:

• To evaluate the effectiveness of Polyvinyl chloride (PVC) as a shielding material against neutron radiation damage to CCD cameras.
• To determine the protective capacity of a PVC enclosure for CCD cameras used in radiotherapy settings.

Main Methods:

• A shielding box constructed with 6 cm thick PVC walls was designed.
• The shielding box was placed around a CCD camera exposed to neutron radiation from a linac.
• Comparative analysis was performed using a similar box made of polyethylene (PE).

Main Results:

• The PVC shielding box extended the operational lifespan of the CCD camera by at least a factor of two.
• Polyethylene (PE) shielding did not effectively reduce neutron damage to the CCD camera.
• PVC effectively mitigates neutron-induced surface damage, unlike PE which primarily moderates faster neutrons.

Conclusions:

• PVC is a cost-effective and easily accessible material for constructing neutron radiation shields for CCD cameras in radiotherapy.
• Implementing PVC shielding is a practical solution to enhance the durability and longevity of monitoring equipment in radiation environments.
• The findings suggest PVC offers superior protection against neutron radiation damage to CCD cameras compared to PE.