D.C. Mun. Regs. tit. 6-B, § 3906
3906.1 Testing for illegal drug use shall be conducted by collecting a urine sample from the individual being tested.
3906.2 Testing for alcohol use shall be conducted utilizing an evidentiary breath-testing device or EBT, commonly referred to as a "breathalyzer."
3906.3 The vendor or vendors selected to conduct the testing shall conduct the breathalyzer test for alcohol use; or collect urine specimens on site for drug testing at a location designated by each personnel authority for such purposes.
3906.4 In the case of drug testing, the vendor shall split each sample and perform enzyme-multiplied-immunossay technique (EMIT) testing on one (1) sample and store the split of that sample. A positive EMIT test shall be confirmed by the vendor, using the gas chromatography/mass spectrometry (GCMS) methodology.
3906.5 The appropriate personnel authority shall notify, in writing, any appointee or employee in a safety-sensitive position found to have a confirmed positive urinalysis test result. The appointee or employee may then authorize that the stored sample be sent to another HHS-certified laboratory of his or her choice, at his or her expense, for a confirmation, using the GCMS testing method.
3906.6 Probable cause or reasonable suspicion and post-accident employee testing shall follow the same procedures set forth in this section. In the case of a reasonable suspicion referral, as confirmed by a second supervisor, or a post-accident employee, a supervisor shall escort the employee to the vendor's test site for specimen collection or a breathalyzer.
3906.7 In the event that a covered employee may require medical care following an accident, medical care shall not be delayed for the purpose of testing.
3906.8 A breathalyzer test shall be deemed positive if the vendor determines that one (1) milliliter of the employee's breath (consisting of substantially alveolar air) contains .38 micrograms or more of alcohol.