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Procedures for Facility User Access
Note: Access for non-users (visitors for discussions, tours, contractors, etc), see Access for Non-Users.
Purpose of Visit | To get access, you MUST register each time | Deadlines | |
|---|---|---|---|
| First Time Facility User | Click here for detailed instructions. | 35 calendar days before arrival is required unless you are a U.S. citizen or permanent resident (with a green card), in which case a minimum of three full business days is needed. | |
| Returning Facility User (if you are unsure of your access status, contact the User Office at ncnraccess [at] nist.gov (ncnraccess[at]nist[dot]gov) or 301-975-8200) | NOT on the NCNR Access list at the scheduled time of arrival | Click here for detailed instructions. | 35 calendar days before arrival are required unless you are a U.S. citizen or permanent resident (with a green card), in which case a minimum of three full business days are required. Questions regarding the 35-day requirement, contact the User Office. |
| On the NCNR access list at the scheduled time of arrival. | Click here to request access. | Three full business days in advance is needed. | |
Created July 24, 2026, Updated July 27, 2026