Revised COVID safety protocols as California reopens

By pjones
July 2, 2021

Dear LCLS User Community,

Across SLAC and the surrounding region, we are continuing to experience significant improvement in COVID-19 conditions. Positive cases are low and immunizations are high.  As of June 15, the state of California has officially reopened its economy, removing or relaxing most physical distancing, masking, and capacity restrictions.

Effective Monday, June 21, SLAC adjusted its COVID safety protocols to align with the latest Cal/OSHA, CDC, and DOE guidance. The primary change is that masking and distancing rules for vaccinated people are being lifted and we will begin to increase the average daily population on site.

We are writing to share with you how SLAC will implement these changes. Please be aware that there may be modifications as conditions and circumstances change, so always consult with your experiment Point of Contact and the LCLS User Office prior to arranging any travel.

Protocol changes

All Onsite Users will need to complete mandatory training prior to access to SLAC, including updated COVID protocol training.


Users who are fully vaccinated for COVID-19 will no longer be required to wear face coverings or maintain physical distance from others, whether indoors or outdoors. Fully vaccinated may elect to voluntarily use face coverings. COVID-19 Return to the SLAC Site requirements will apply for users traveling from outside California.  COVID-19 testing is available at SLAC.

To be counted as fully vaccinated, you need to have had a vaccine recognized by the Center for Disease Control (CDC) or World Health Organization (WHO), with the final dose administered at least 2 weeks prior to access to SLAC. Proof of vaccination must be shown to the Security Badging Office prior to starting work.

Non-vaccinated, second dose of a 2-series vaccine pending, or decline to state status

Users who are not vaccinated may still be at heightened risk of contracting COVID-19, so many of our current COVID safety protocols will remain in place to ensure their continued safety. For those who are not fully vaccinated, or decline to state their status, additional COVID-19 Protocol Matrix requirements will apply, including face coverings and physical distancing. This includes a daily ‘Health Check’ questionnaire using an online process. Contact the User Office for details.

Individuals do not need to self-isolate or test prior to coming onsite.  Work will be limited to Levels 1 & 2 until either a negative test is obtained 5 days or more after arrival in CA, or a 10-day waiting period with no symptoms. Level 3 & 4 work can proceed afterward, subject to approval by the local Area Manager. COVID-19 testing is recommended for individuals from domestic locations for Level 1 & 2 work; COVID-19 testing is required for individuals from an international location for Level 1 - 4 work. SLAC will provide weekly testing and N95 face coverings as required.

Unvaccinated users who are unable to wear a mask due to medical conditions and/or disabilities should work with the SLAC Occupational Health Center to request an accommodation.

Respecting each other’s personal circumstances

Please keep in mind that many people in our community, even those who are vaccinated, may choose to continue wearing face coverings. Some may be taking extra precautions for family members at home, while others may be more comfortable adjusting gradually. We should expect and respect these sorts of decisions.

If you have questions or concerns around these new rules, please review the SLAC Access for Users on the LCLS website, ask your experiment point of contact or send a message to the User Office at

We appreciate the efforts of our staff and user communities that have worked with local and federal authorities to enable LCLS to continue to deliver world-class research during this uniquely difficult period. We look forward to the resumption of operating in a more traditional environment, while retaining ongoing benefits from our enhanced connectivity to offsite staff and users.

Mike Dunne
Director, Linac Coherent Light Source