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X-ray Facility Safety Review

Radiation Safety

The following information is an application of basic radiation safety to the situations encountered in our laboratories.  A familiarity with the fundamental radiation concepts presented in the University radiation safety training films is presupposed.

Sources of Radiation

In our facilities there are two types of radiation:

General Philosophy of Acceptable Radiation Exposure

The equipment in our laboratories is equipped with safety interlocks in order to eliminate accidental exposure.  Our goal is that one should receive no exposure during routine operation of the equipment.  Even during alignment procedures exposure is to be avoided.

Principles of Radiation Exposure Control

There are three aspects of exposure control important in the lab:

Personal Dosimetry

Individuals using the x-ray equipment are monitored to record accidental exposure.  Dosimetry is not a preventative measure, but allows exposure to be quantified.  Dose monitoring will be done using a TLD ring obtained from the university's Environmental Health and Safety Radiation Protection office.  Rings are stored in a cabinet in room 8.  If you have your own ring, wear only the ring assigned to you.  If you are using one of the laboratory's visitor rings wear the same ring every time, if possible.

Legally Permissible Dose Limits

While our goal is to minimize exposure, federal and state regulators have established radiation dose limits.  If these limits are exceeded, the individual will not be allowed to perform any more experiments.

Laboratory Access

Access to the lab is limited to authorized individuals.  Users are required to complete safety training including viewing of the following tapes:
     For Wide Angle Diffraction
           "The Double-Edged Sword"
     For Small Angle Diffraction
           "The Double-Edged Sword"
           Radiation Protection Program Tapes 1, 2, 3, 5

Also required is a review of our laboratory's specific policies as outlined in this document.  A record of the training sessions will be kept on file.

Equipment-Specific Safety Aspects

There are slight differences in the safety considerations for each of the various radiation sources.  Each x-ray generator has an "x-ray on" light that is hard-wired into the instrument's safety circuit.  Check to see if the "x-ray on" light is lit before logging your time on the computer.  Check the box on the log sheet indicating that the x-ray on safety feature is working.

Siemens D-500 and Bruker-AXS D-5005

Panalytical X'pert

Bruker-AXS Rapid Microdiffractometer--Rotating Anode

Fe55 Source

Scintag XDS-2000

Bruker-AXS Microdiffractometer


High-Resolution 6-meter SAXS



  1. Do as much sample preparation as possible before entering the lab.  There is no hood, so use solvents sparingly.
  2. Samples may remain in the lab only while you are present.  Please take them with you when you leave.  Don't throw chemicals in the trash!
  3. Clean the sample holders (and mortar and pestle if you used them) and the sample preparation area before you leave.
  4. If you are working with anything particularly hazardous, let the lab manager and others working in the lab know.

Emergency Telephone Numbers

In case of an emergency, the following numbers are provided:
Environmental Health and Safety Radiation Protection:  612-626-6002
After Hours:  911
Tell them you are in room 8 or 22, Shepherd Labs, phone number 612-626-0776 and give them a brief description of the incident.

General Laboratory Safety

  1. No food or beverages in the facility.
  2. The laboratory's Chemical Hygiene Plan is available at
  3. Gas cylinders must be fastened securely.
  4. Eye washes are located in rooms 8 and 22b.
  5. Fire extinguishers are located in each room.


The facility director is responsible for enforcing the laboratory safety policy.  Safety policy infractions will result in the individual being asked to leave the lab for a period of not less than one day.  Grievous negligence could lead to permanent removal from the lab.

I have reviewed and understand the information in the X-ray Facility Safety Review

Signature of User


Signature of Trainer


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Last update: May 2005 by Characterization Facility Webmaster.