Answer to Question #10292 Submitted to "Ask the Experts"
Category: Radioactive Waste Disposal and Decommissioning — Decommissioning
The following question was answered by an expert in the appropriate field:
High energy x-ray machines are used for cargo and container screening. What are the requirements and procedures for decommissioning of such machines?
The procedure for decommissioning x-ray machines depends on the type of the generating device and its construction. Several manufacturers, upon purchase, provide users with the option to return the equipment for disposal at a cost. The cost varies among manufacturers. If the return option is not available, the machine could be disassembled according to the manufacturer’s specific procedures and its individual components disposed of accordingly.
X-ray machines do not present a radiation hazard when they are not in operation. Additionally, activation of structural components is not likely due to the nature of the produced radiation and its interaction with the structural materials. However, many structural components are built with materials that may be considered hazardous (e.g., lead, tungsten) for disposal purposes. These materials may be segregated and disposed of according to the regulatory agency having jurisdiction.
It is common for users to disassemble the x-ray machines (including x-ray generating tube) and dispose of the individual components as industrial waste upon clearance by a radiological survey. In the United States, this is only performed under a license authorizing disposal or by a holder of a certificate of accreditation to decommission a radiation source. Radiation apparatus that still has its x-ray generating tube attached may not be disposed of as industrial waste.
X-ray generating machines are usually registered with the regulatory agency having jurisdiction. The regulatory requirements may vary among agencies and devices. It is recommended that users contact the regulatory agency and seek advice regarding specific requirements prior to dismantling and disposing of any x-ray generating device. Additionally, if a license is required for the use of x-ray machines, the user should seek removal of the machine from its license upon decommissioning and disposal.
Manuel Diaz