X-Ray Calibration


In the State of Minnesota you are required to do several types of testing at regular periods to maintain your X-ray and processing equipment.


Minnesota’s 4732 Radiation Rule

MDH Informational notice on ALARA
MDH How to survive a site inspection


PROCESSOR QC: Perform Processor Quality Control using a CrabTree or Aluminum stepwedge depending on whether you have only intra-orals or if you have an extra oral cassette (pan or ceph). A test must be done per processor. Daily testing records and films must be kept.

MDH Processor QC Crabtree Form
MDH Processor QC Stepwedge Form

Every 6 months:

FOG TESTING: Fog Testing of the dark room – This is sometimes called the “penny test”. We check for light leakage by placing a coin on an un-exposed film and then we dance around in the dark room for two minutes. You do not want to remain stationary as you may be blocking rays of light. If the processed film shows no outline then the darkroom is sealed. If an outline is visible however, there is a light leak that is fogging the film and the light leak must be eliminated.

MDH Darkroom Fog Testing Intraoral
MDH Darkroom Fog Testing Extraoral



SAFETY INSPECTIONS: X-Ray machines must be checked for structural integrity and normal operation. This inspection is normally performed by a staff member designated as the Radiation Safety Officer or RSO.

MDH Yearly Radiation Program Audits – work in progress


CALIBRATIONS: All X-Ray machines must be inspected / calibrated by a service technician. These reports must be kept. We use the most advanced testing equipment in the state, the Unfors Xi. Call us at (800) 826-8704 to request this service.



R-Tech Blank Calibration Record
R-Tech Intra-Oral Technique Charts (3)
R-Tech Panoramic Technique Charts (3)
R-Tech Cephalometric Technique Charts (3)
MDH Dental Technique Chart Information

Unfors Xi R/F Test Tool Calibration

Minnesota State Provider License

FILM SCREEN CONTACT: Film screen contact must be performed by a technician with a Screen/Contact test tool. Films from these tests must be kept. Call us at (800) 826-8704 to request this service.

MDH Screen Contact Test Instructions

CASSETTE SPEED MATCH: Cassette Speed match must be performed if you have more than one extra-oral cassette of the same type (aka two pan cassettes or two ceph cassettes)

MDH Cassette Speed Match Test Instructions
CRCPD Screen Film Speed Combinations – work in progress

X-Ray Installation / Registration:

All new X-Ray installations or changes to X-Ray installations require registration paperwork to be completed.

MDH Initial registration of X-Ray equipment
MDH Adding new X-Ray equipment to your office – work in progress
MDH Moving X-Ray equipment to another branch office
MDH Changing facility ownership or facility information


All new facilities or office remodels that will contain a Panoramic or a Cephalometric X-Ray require a shielding plan to be filed and approved by the state prior to installation of the pan or ceph. Placards need to be placed within Pan/Ceph rooms that show the shielding plan.

MDH Shielding Plan Review
MDH Shielding Placard Requirements
MDH Occupational Exposure – work in progress

X-Ray Waste:

Many offices are going digital and avoiding this problem all together, but for the offices that still use film processors it is necessary that the film waste, fixer, and lead foil all be handled properly. Below are instructions from the MPCA on how to do that, and a contact list of existing waste haulers. The MDH also has a list of local waste disposal companies.

MPCA Managing photographic and X-Ray waste
MPCA Form 6.11 List of hazardous waste haulers
MDH Disposal Services List

Additional requirements:

Staff training
Radiation control manual
Various printed material

For creation of a radiation safety program or the creation of a radiation safety manual, we recommend that you contact:

Statements Plus Compliance Solutions
Leanne M. Mathieu Kramer
Phone: (763) 271-1924
Fax: (763) 271-1925