Personal Safety Checklist for X-ray Diffraction

Last revised 9/20/10. This file can be accessed at http://msg.ucsf.edu
All Authorized Users are required to agree to these policies in writing prior to entering the restricted area. For details, see Chris Waddling.

General information:

Safe Practices: Users must take responsibility for the lockbox key at the beginning of every data collection run by signing the log-book next to the lockbox. At the end of each run, users must relinquish responsibility for the key by signing the log again.

Telltale Lights Users should check the Power and Shutter lights every time they walk into the room. Each light operates in an interlock circuit such that if the light is off, you are guaranteed that either the Power is off, or the Shutter is closed.
Beamstops Beamstops serve two functions: to shorten the path of air scatter, and to protect the image plate. Users should check that the beamstop is in place whenever x-ray power is on, regardless of the shutter status. If you wish to remove the beamstop to check the direct beam position, you must remain in the room while you are doing the experiment.
Protecting Your Fingers from the Direct Beam When you manipulate anything in the vicinity of the goniometer, you should assume that the shutter is open and that there is no beamstop: therefore do not put your fingers in the path of the direct beam.
Generator Room Access Generator rooms are not shielded from air scatter.
Beam-confinement Labyrinths Labyrinths are junctions between two pieces of equipment through which the beam passes. Any small disturbance of the x-ray optics can ruin the alignment, and reduce the beam intensity. In this event, call Chris Waddling for assistance. Furthermore, if the equipment is severely distorted, dangerous amounts of x-rays can leak out. Visually check that the beam path is properly intact before opening the shutter.
Survey Meters Users should know how to conduct radiation survey with portable meter.
X-ray Shutter When data are not being collected the shutter switch should be closed. Before opening the shutter, double check that the beamstop and shields are in place, and that the labyrinths are properly aligned.
Visitors Visitors must be escorted by an authorized user. It is considered to be a risk factor to bring visitors into the generator rooms.

Information specific to the x-ray detector:

Detector RaxisIV
Room S174
Room Access Access by proximity card via S127/S176, then key in lock-box (code given to trained users only)
Generator RU-200 (Charybdis)
Normal Operating Power 50 kV x 90 mA
How to check the status of the x-ray power Red "XRAY Power" lamp above anode housing; Voltage and Current gauges on front of generator
Installation Port Right
Number of independent shutters One
Operation of shutter control switch Up = Open (used only by CAW for direct beam shots)

Middle = closed (no computer control)

Down = external software control (normal data collection mode)

How to check the shutter status Two shutter lamps above anode housing
Beam-containment Labyrinths Interface between Osmic and collimator


Web page maintained by Chris Waddling. Last modified: 9/20/10