49 C.F.R. § 40.183
What information do laboratories report to MROs regarding split specimen results?
(a) As the laboratory responsible for testing the split specimen, you must report split specimen test results by checking the “Reconfirmed” box and/or the “Failed to Reconfirm” box (Step 5(b)) on Copy 1 of the CCF, as appropriate, and by providing clarifying remarks using current HHS Mandatory Guidelines requirements.
(b) As the laboratory certifying scientist, enter your name, sign, and date the CCF.