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

APS Operations and General User Programs During the COVID Pandemic

Argonne National Laboratory and its user facilities, including the Advanced Photon Source (APS), remain in a limited state of operations. 

The Laboratory and the APS are committed to helping protect the health and safety of everyone who visits our site. The following outlines COVID protocol and site access requirements currently in place. 

On-site Rules that Apply to Everyone

  • Users should not come to Argonne or the APS if they are not feeling well or exhibit any symptom(s) consistent with COVID-19, regardless of vaccination status. 
  • Users who develop symptoms consistent with COVID while on-site should call the COVID line at 630-252-2555 and Argonne Health and Employee Wellness staff will advise next steps.
  • Site access can only be granted to users identified as onsite users on approved Experiment Safety Assessment Forms (ESAFs), or if a gate pass is requested and processed by the User Program Office.  Visit the My APS Portal to request a gate pass or email
  • All visitors and users should have their appropriate vaccine documents and/or test results with them when they arrive at Argonne.  If documents are not available, SITE ACCESS WILL BE DENIED. 
  • All users must go the Argonne Information Center (AIC) upon arrival to Argonne to show proof of vaccination, exemption letter, testing results or to pick-up a site access credential.  This is not required for CAT operations staff.

    The AIC hours are 6:30 a.m. - 5:00 p.m. Central Time, Monday through Friday.  See further details on vaccination requirements and after hours, weekend, holiday, and shutdown requirements below.

  • The User Program Office and the AIC staff are not available during non-working hours.  Users /visitors who arrive at Argonne after hours without notifying the APS User Office in advance of arrival WILL BE DENIED ACCESS. 
  • Mail-in and remote-access experiments at the APS continue and remain encouraged and should be identified accurately on ESAFs. 
  • Face coverings are required at all Argonne facilities, regardless of an individual’s vaccination status.  Click here for more information. 
  • Social distancing of at least 6 feet is required at all times, whenever possible.  Wearable Proximity Devices are available to ensure social distancing is maintained and should be worn while working at the APS
  • Information Regarding ESAFs
  • Information about Vaccines, Requirements, Exemptions, and Testing
  • Vaccination Requirements for Site Access
  • After-hours, Weekend, Holiday Access, and Shutdown Periods

Questions pertaining to approval for onsite experiments or site access requirements should be sent to If you have additional questions or require an exception because you are unable to meet the requirements above, please contact



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