The Advanced Photon Source
a U.S. Department of Energy Office of Science User Facility

Experiment Hazard Class 8.3 – X-Ray Generators


This hazard classification applies to all experiments involving the use of X-Ray Generators (excluding the APS storage ring).

As specified in LMS-PROC-109 a Radiation Generating Device (RGD) must be registered with the Argonne RGD Safety Officer using an ANL-847 form.  The RGD will be assigned an inventory number, hazard class, RWP requirement, and inspection and survey frequency requirements.

Experiment Category

Experiments in this experiment hazard class are categorized as high risk or medium risk dependent upon review of the system.

Experiment Hazard Control Verification Statements

Engineered Controls – As determined in LMS-PROC-109.  Sample chambers and all beam paths must be fully enclosed by barriers.  Class 1, Class 2, and higher RGDs require an interlock to fail-safe beam shutter/beam stop or radiation generator power supply and completion of an ANL-848 form - Radiation-Generating Device Inspection.

Procedural Controls – A Standard Operating Procedure is required that addresses the following:

  • RGD normal operation instructions
  • Emergency response, including off-normal alarms, abnormal external radiation level, and proper notification procedures to follow in an emergency
  • Methods and occasions for locking and securing the RGD
  • Calibration and alignment of the useful beam, as needed
  • Documentation of operational checks, inspections, and testing records
  • Control of keys or computer passwords for RGD operation
  • Interlock test procedure

Design Reviews and Equipment Inspections – The need for engineered or procedural controls will be determined by review with RSO-HP and the PSC ESH Coordinator.


  • Class 1 RGD - ESH738 (GERT)
  • Class 2 or higher RGD: Radiological Worker for X-Ray Users (ESH713), Analytical X-Ray Device Safety (ESH705)

Signs and Labeling – All signs and postings required for the area will be supplied by RSO Health Physics.

Personal Protective Equipment – As determined in the review of the experiment.

Dosimetry and Monitoring – Dosimetry requirements are determined during the review of the experiment.

Experiment Authorization

Unless otherwise noted in the approved experiment safety plan, the PSC Deputy Associate Laboratory Director of Operations delegates the authority to authorize an experiment in this hazard class to a member of the APS Experiment Safety Review Board and resident beamline personnel having the authority to authorize experiments as listed in the ESAF system.  Approval by both the host beamline and APS Experiment Safety Review Board are mandatory prerequisites for experiment authorization.

Hazard Control Verification

The PSC Deputy Associate Laboratory Director of Operations delegates responsibility for verifying that required controls are in place to RSO Health Physics, the experiment On-Site Spokesperson, and Beamline Management.


Argonne Radiological Safety Program Description 1/9/2017 (Internal link)

LMS PROC-109: Control of Radiation Generating Devices 5/13/2019 (Internal link)

LMS PROC-143: Radiation Safety Interlock System 8/29/2019 (Internal link)

Contact the APS User Safety Program with any questions or if the internal links are not working properly.

Reviewed: January 21, 2022