Radiation-Producing Machines

A radiation-producing machine is any device capable of producing ionizing radiation when the associated control devices are operated. X-ray diffraction and radiography units, particle accelerators and high voltage rectifiers operating above 5 keV all fall into the category of radiation-producing machines.

  • Regulation: Use of radiation-producing machines is regulated by the State. Weizmann's policies for the use of radiation-producing machines are designed to ensure the safety of users and other personnel.
  • Registration: Radiation-producing machines must be registered with the State and a registration fee paid. Registration will be in the name of the Institute, with the Radiation Safety Office as the point of contact. The Safety Office must be notified of the acquisition, transfer, or disposal of any radiation-producing machine.
  • Application for Use: Faculty members who wish to operate a radiation producing machine must submit an "Application for Use of Radiation-Producing Machine Form"e; to the Radiation Safety Officer, describing the machine and its usage.

Accelerators, diagnostic or radiographic x-ray machines, or other radiation-producing machines which may present special hazards require operating conditions beyond those listed in this chapter.

Policies and Procedures for Use of Radiation-Producing Machines

  • Authorized Users: Principal Investigators are responsible for ensuring that only authorized users are allowed to operate their machines. Authorized users are those individuals listed on the original application.
  • Training Requirements: New personnel must be trained by the Principal Investigator (or an experienced qualified operator designated by the P.I.) and must satisfactorily demonstrate knowledge of operating and safety procedures before independently operating a radiation-producing machine. New personnel may be required to attend an orientation with the Radiation Safety Office.
  • Posting:
    • A sign bearing the radiation symbol and the words CAUTION X-RAYS or CAUTION IONIZING RADIATION must be posted at the entrance to each laboratory containing a radiation-producing machine.
    • A label bearing the words CAUTION THIS EQUIPMENT PRODUCES RADIATION WHEN ENERGIZED (or similar wording) must be affixed to the control device of each machine. 
    • A label bearing the words CAUTION HIGH INTENSITY X-RAY BEAM (or similar wording) must be affixed on or near the tube of an x-ray unit.
    • An X-RAYS ON warning light, labeled as to its meaning, must be located on or near an x-ray tube to indicate when x-rays are being produced.
  • Access Control: While any radiation-producing machine is in operation, an operator must be present or the laboratory must be kept locked.
  • Operating Procedures: Operating procedures and safety regulations for each machine must be posted near the machine. These procedures must specifically include:
    • means to control and limit exposure to individuals, including controlling access to the area.
    • The use of radiation survey instruments and film badges.
  • Surveys: The Principal Investigator must provide a radiation survey meter to indicate the presence of unwanted radiation and to trace the origin of leaks. Before energizing the machine, the operator must visually make sure that no unauthorized individuals are present, inspect ports, electronic safety devices, shielding, etc. After the machine is energized, a radiation survey should be performed to check for scattered or leakage radiation.
  • Shielding: Protective barriers and/or shielding must be used in x-ray systems. It is important to avoid cracks and gaps in the shielding.
  • Log Book: A log book must be kept which records the following information:
    • Operator
    • Date
    • Voltage
    • Current
    • Exposure time
    • Radiation survey results
  • Dosimetry: Dosimetry requirements will be established by Radiation Safety upon a review of each facility. Users of accelerators, radiographic units, or open system x-ray diffraction units will be issued a personnel dosimeter (film badge). This dosimeter should be worn while in the facility when the machine is in operation. Radiation Safety may position dosimeters at various locations in the facility to measure environmental exposure. These dosimeters should not be moved by laboratory personnel.
  • Radiation Safety Surveys: Radiation Safety performs routine inspections of radiation-producing machines and upon request of the user.

Emergencies Involving Radiation-Producing Machines

In the event of an accident or unusual incident involving a radiation-producing machine:

  1. Turn off the machine; if possible, also unplug or shut off the electricity circuit and leave the area.
  2. Notify the emergency center (08-934-2999) and to the Safety Officer.
  3. Notify the laboratory supervisor or Principal Investigator.
  4. Record information about the incident (e.g., operating voltage and current, exposure time, distance from radiation source).