X-ray Facility Safety Review

Radiation Safety

Sources of Radiation

• machine-produced X-ray radiation in Rooms 8 and 22 Shepherd Labs
• X-rays from a radioactive material: Fe₅₅ in Room 8 Shepherd Labs

General Philosophy of Acceptable Radiation Exposure

Principles of Radiation Exposure Control

• Equipment is periodically monitored using a hand-held Geiger counter radiation monitor.
• Sufficient shielding is provided so that no exposure occurs during general usage.
• During alignment additional shielding is used, including lead aprons and distance (remote tools) to avoid exposure.  Placing any part of the body in the pathway of the X-ray beam is to be avoided at all times.

Personal Dosimetry

• Record the ring number in the comment section of the computer log.
• Wear the ring at all times while in the lab.
• Wear the ring with the TLD turned towards the source of the x-rays.
• Do not intentionally expose the personnel-monitoring device to radiation, contaminate it with radioisotopes, or damage it in any way.
• When not in use, the ring should be stored in the storage cabinet in room 8.  Do not take it home to avoid loss or exposure to stray radiation.  If you accidentally remove the ring from the lab, make a notation in the comments section of the computer log.
• The Radiation Protection Program maintains a permanent record of the radiation dose accumulated by each individual monitored at the University.  An individual may request information on his or her radiation dose history from the Radiation Protection Program at any time.
• Rings are exchanged by the X-ray Scattering Lab staff and the Environmental Health and Safety Department four times a year for analysis.
• Quarterly dosimetry reports are kept on permanent file by the facility director.  Individuals may see their reports at any time.  The individual will be notified if any significant exposure is detected.
• Visitors to the lab must be monitored using visitor rings.  The ring number and name of the individual using the ring must be recorded in the comment section of the computer log.

Legally Permissible Dose Limits

• The limits for people who are not pregnant and who are exposed in the course of their occupation are:
  1. whole body dose - 1.25 rem/qtr (100 mrem/week)
  2. extremity dose (hands, feet) - 18.75 rem/qtr (1.45 rem/week)
  3. skin of whole body - 7.5 rem/qtr (575 mrem/week) - 30 rem/year


• A recommended maximum dose level for pregnant women is 100 mrem/9 months gestation.  Exposure during the first trimester is the most hazardous.  Generally, pregnant women should not be assigned to a radiation use area during pregnancy unless exposures potential is demonstrated to be below 100 mrem/9 mo.
  

  There are special requirements for pregnant women.  If you are pregnant, you have the option of notifying Linda Sauer of your condition (in writing) and she will initiate the special training and radiation monitoring.



• The radiation protection guide's limit for an individual in the general public (e.g. a visitor) is 100 mrem/year.

Laboratory Access

Equipment-Specific Safety Aspects

Siemens D-500 and Bruker-AXS D-5005

• Shutter interlock--The shutter will close or X-rays will shut off if the door is opened when the shutter is open.

Panalytical X'pert

• The shutter will not open if the doors are open.  The doors are locked when the shutter is open.

Bruker-AXS Rapid Microdiffractometer--Rotating Anode

• The shutter will not open if the enclosure doors are open.
• Work in front of the system-There is an exposed pulley in the back and many cables on the floor.
• Caution!  Never remove the lead shields opposite the anode ports.

Fe₅₅ Source

• Storage:  Keep Fe₅₅ source in the locked cabinet when not in use.
• Usage:  Wear the lead apron and keep the source pointed away from you.

Scintag XDS-2000

• The shutter closes when the door is opened.

Bruker-AXS Microdiffractometer

• The shutter closes when the door is opened.  Do not use the interlock by-pass key!

2-D SAXS

• Shutter interlock on sample chamber.
• Use the manual (yellow) interlock in front of the shutter when opening sample chamber.
• Use caution near the exposed pulley at the back of the tube tower.

High-Resolution 6-meter SAXS

• shutter interlock on sample chamber and rheometer lid.
• Use the manual (yellow) interlock in front of the sample chamber prior to opening sample chamber-- it must be at a 45 degree angle.

SAXSess

• Interlocks on camera-shutter will not open unless interlocks are secure.

Samples

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

Environmental Health and Safety Radiation Protection:  612-626-6002
After Hours:  911

General Laboratory Safety

1. No food or beverages in the facility.
2. The laboratory's Chemical Hygiene Plan is available at http://www.charfac.umn.edu/safety/chp.html
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.

Enforcement

ACKNOWLEDGEMENT OF UNDERSTANDING

I have reviewed and understand the information in the X-ray Facility Safety Review
___________________________________ Signature of User	__________________________ Date
___________________________________ Signature of Trainer	__________________________ Date

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