The May 11, 2026, final rule (effective June 10, 2026) updates Part 40 terminology and clarifies that, where an oral-fluid collection would be required, but oral fluid isn’t available, a directly-observed urine collection must be used instead. It does not add oral-fluid testing as a usable option and does not change who is tested or when. DERs and collectors should review procedures before June 10, 2026.