DEEP: Inspection of Medical X-Ray Machines

Inspection of Medical X-Ray Machines

The following information is provided to familiarize the medical x-ray community with Connecticut’s inspection process and help individual facilities comply with state regulations ensuring safe, high quality x-ray examinations with exposures to patients, operators and non-occupationally exposed individuals that are as low as reasonably achievable.

General Information

Inspections of medical x-ray machines in Connecticut are conducted by the Department of Energy and Environmental Protection, Bureau of Air Management, Division of Radiation.

Inspectors typically provide advanced notifications of facility visits. If your facility is to be visited, the state inspector will contact the person who is most accountable for your x-ray program to schedule the inspection. State inspectors make every effort to accommodate a facility's patient schedule. Inspectors are instructed to work with facility staff when on site and to avoid disruption of patient care whenever possible. It should be noted that state statutes require that facilities provide reasonable access to inspectors.

Inspection Duration

The length of an inspection varies and is contingent upon the number of x-ray tubes at your facility, your patient schedule and the number of questions you may have regarding the inspection or other related matters. Generally, administrative record review takes 30 minutes to 1 hour. The average inspection time for a facility with three tubes is approximately 2.5 to 3.5 hours not including the exit interview.

It should be noted that inspectors travel to all areas of our state and on occasion weather, traffic and delays at other facility inspections may cause an inspector to deviate from a scheduled inspection time. Inspectors are instructed to inform facilities of significant delays in their arrival.

Records Needed for Inspection

To facilitate the inspection process and avoid confusion and delays, each facility should have the following records available for review at the time of inspection.

  1. Written radiation safety practices.
  2. Current registration form.
  3. Maintenance, preventive maintenance, calibration records and owner operator manuals for all of your x-ray units and film processing systems.
  4. Dosimetry badge reports.
  5. The approximate numbers of exposures made in each operatory per week.
  6. The frequency of your processing system(s) chemical changes.

X-ray units may be inspected for the following:

  1. Radiation safety:
    1. The physical layout that will allow an operator to stand at least six feet from the source of ionizing radiation or behind a protective barrier during x-ray exposures.
    2. Testing to ensure that the exposure control terminates the x-ray exposure when pressure is released from exposure control button.
    3. Availability of technique charts indicating machine settings for various projections and patient sizes.
    4. Availability of patient protective shielding and proper storage of same.
    5. Stability of the tube head: Does the tube remain in position without human assistance?
    6. Visual evaluation of the tube head to ensure that it is not damaged or leaking oil.
    7. Measurement of beam size to ensure that it does not exceed regulatory requirements.
    8. Visual evaluation to ensure that the cone/collimator is intact and in place.
    9. Measurement of stray radiation levels.
  2. X-ray unit operating characteristics:
    1. Measurement to ensure that kVp accuracy is within plus or minus 10% of the selected kVp.
    2. Measurement of timer accuracy within plus or minus 10% of a pre-selected time.
    3. Reproducibility: Measurement to ensure that the radiation output is consistent, to within plus or minus 10%, when all machine settings remain the same.
  3. Half Value Layer:
    1. Is the x-ray beam properly filtered?
    2. Entrance skin exposure: Is the measured entrance skin exposure (ESE) for the average patient within the accepted range established by the U.S. Food and Drug Administrations' Center for Devices and Radiologic Health?

Film and Film Processing Systems

One of the most important aspects of ensuring low dose, standardization of technique and good quality images is directly related to film handling and film developing procedures. It is essential that film developing solutions are not allowed to lose their effectiveness either by oxidation or improper temperature. It is also essential that processors and developer solution tanks be regularly cleaned and that chemicals are frequently changed. Without proper film developing procedures, the entrance skin exposure administered (ESE) to patients increases and image quality decreases.

The Department of Energy and Environmental Protection stresses, that without proper maintenance of x-ray equipment and constant vigilance of film developing methods, a facility usually exposes their patients to more radiation than necessary and experiences a significant loss of image quality.

The following items are evaluated during inspection of film handling and film processing systems.

  1. Film speed: Is the film utilized by the facility the fastest speed consistent with the diagnostic objective of the examinations?
  2. Logs: Are logs or other means available which indicate dates of solution changes and processing system cleanings?
  3. Visual inspection of developer solutions for oxidation.
  4. Environmentally safe chemical disposal. It is illegal for film fixer solutions to be dumped into sewer systems.
  5. Dark room and developer system cleanliness.
  6. If applicable, dark room light leaks.
  7. Manual processing system for thermometer and timer to standardize development of films.
  8. Posting of suggested development times and temperatures.

Exit Interview

The most responsible individual available is verbally informed regarding the scope of the inspection, any findings and required corrective actions.

Written Reports

Written inspection reports are provided to all inspected facilities. The reports are usually received by a facility within thirty working days of an inspection. Inspection reports describe the focus of the inspection and lists areas which require corrective actions. Facilities are responsible for providing written documentation of their corrective actions to the DEEP within 30 calendar days from receipt of the inspection report. Each facility is provided with a statement of compliance when all corrective actions are completed and documented

For further information, please contact the Radiation Division by phone at 860-424-3029.

Diagnostic and Therapeutic (Medical) X-Ray Device Program

Content Last Updated March 2010