Drug Field Tests

The field tests for detection of drugs for use in preliminary hearings under § 19.2-188.1(A) that have been evaluated and approved by the Department of Forensic Science are accessible in the links below.

“Field test” means any presumptive chemical test or any presumptive mobile instrument used outside of a forensic laboratory environment to detect the presence of a drug.


Under Virginia Code § 19.2-188.1, the Department of Forensic Science approves field tests for use by law enforcement officers pursuant to regulations adopted in accordance with the Administrative Process Act (Virginia Code §2.2-4000 et seq.). Under 6VAC 40-30-30(E), the Department is to “use commonly encountered street drug preparations to examine those field tests submitted for evaluation.”

The regulation further provides that, “[i]n order to be approved, the presumptive chemical test must correctly react in a clearly observable fashion to the naked eye and perform in accordance with manufacturers’ instructions and claims.” In addition, “the presumptive mobile instrument must perform in accordance with the manufacturer’s instructions and advertised claims and offer convenience and efficiency in operation as determined by the department.”

Presumptive mobile instruments may provide benefits such as the ability to scan directly through plastic or glass packaging to reduce exposure and minimize contamination. However, they may not be able to detect drugs in low concentrations within a mixture. There are many drugs, such as synthetic opioids, that remain dangerous even when present in low concentrations.  Therefore, mobile instrument users should continue to take safety precautions designed to prevent exposure to dangerous substances during the handling, testing, and/or transporting of suspected controlled substances.  

The results of any approved field test are considered presumptive, and law enforcement officers should submit any suspected controlled substances to DFS for confirmatory analysis.  

Please note that the most recent version of the Virginia Register of Regulations will provide the most up-to-date list of approved field tests.

Published Lists:

  • Chemical Tests: Official version is published in the General Notices/Errata Section of the Virginia Register of Regulations, Volume 39, Issue 12, January 30, 2023, pages 1519-1523.
  • Mobile Instruments: Official version is published in the General Notices/Errata Section of the  Virginia Register of Regulations, Volume 39, Issue 15, March 13, 2023, page 2073. 

Interested in reading more about mobile instruments for field testing of seized drugs?