“Drug test” covers several very different collections. Choosing the right specimen starts with the question you are trying to answer: recent use, current impairment, or a pattern over months.
Urine
The workhorse of workplace testing and, today, the only specimen actually used for DOT drug tests (DOT also authorizes oral fluid; see below). A laboratory urine test detects most drugs for roughly one to several days after use, depending on the drug and the frequency of use. It is well understood, widely accepted and inexpensive. Its limits: it reflects recent use rather than a long history, it says nothing about impairment at the time of collection, and it requires a restroom and, in some situations, an observed collection.
Hair
Hair incorporates drugs as it grows. A standard head-hair sample reflects roughly the previous three months, and a segmented sample can show a month-by-month pattern. Hair is difficult to adulterate and useful for pre-employment, court and monitoring situations that want history rather than a snapshot. It does not show use in the most recent several days and is not permitted for DOT tests.
Oral fluid
A saliva swab detects very recent use, typically the last day or two, and is easy to collect under observation. DOT regulations authorize oral fluid drug testing, but it cannot be implemented until at least two laboratories are certified by HHS for oral fluid testing, and that minimum has not yet been met. Until it is, DOT drug tests remain urine collections, and Local Mobile Drug Testing does not perform DOT oral fluid collections. Non-DOT programs may use oral fluid under their policy.
Breath
Breath testing measures alcohol only, and it measures current concentration rather than past use. For DOT tests, screening may be done on an approved alcohol screening device (ASD, which may be breath or saliva) or an evidential breath testing device (EBT); a screening result of 0.020 or greater requires a confirmation test, which must be on an approved EBT after the required waiting period. Breath is also the standard for post-accident and reasonable suspicion alcohol tests in most Non-DOT programs.
Blood
Blood testing is precise but invasive and is rarely used in workplace programs; it appears mostly in medical and law-enforcement settings. It is not used for DOT workplace tests.
EtG (a special case)
EtG is not a specimen type but a laboratory test, usually on urine, for an alcohol metabolite that remains detectable for days after drinking. It answers “has this person consumed alcohol recently,” not “are they impaired now,” and is used in monitoring and court programs. It is not used for DOT alcohol tests.
Quick comparison
| Specimen | Detects | Approximate window | DOT permitted? |
|---|---|---|---|
| Urine (lab) | Drugs | About 1 to several days | Yes (drugs) |
| Urine (rapid screen) | Drugs, preliminary | About 1 to several days | No |
| Hair | Drugs | About 3 months (segmentable) | No |
| Oral fluid | Drugs | About 1 to 2 days | Authorized, but not yet available (fewer than two HHS-certified labs) |
| Breath (EBT) | Alcohol, current | Hours | Yes: screening and confirmation |
| Saliva alcohol (ASD) | Alcohol, current | Hours | Screening only |
| Urine EtG | Alcohol, recent | Days | No |
Every specimen above can be collected at your location. See all services or starting prices.