How DOT Random Selection Works for CDL Drivers
Random testing only works if drivers cannot guess who is next. That is why 49 CFR 382.305 sets clear rules for how drivers are picked and when they are tested. This guide walks through those rules in plain English.
Updated September 28, 2026 · Checked against the federal regulations
Who goes in the random pool
Every CDL driver who does safety-sensitive work for you must be in a random pool. Only covered drivers can be in it (382.305(j)(1)). Office staff and non-CDL workers do not belong in a DOT pool.
You can run your own pool, or you can use a service agent such as a C/TPA. With a C/TPA, your drivers can be part of a larger pool with drivers from other companies (382.305(j)(2)). Either way, you are still responsible for making sure the pool is tested at the required rate and holds only covered employees.
FMCSA sets the minimum yearly random testing rates. See our guide to 2026 random testing rates for the current numbers.
The selection must be scientifically valid
Under 382.305(i)(1), drivers must be picked using a scientifically valid method. The rule gives examples like a random number table or a computer random number generator matched to Social Security numbers, payroll ID numbers, or similar ID numbers.
This means a manager cannot hand-pick drivers, skip someone, or pull names in a way that is not truly random.
- Every driver must have an equal chance of being picked each time a selection is made (382.305(i)(2)).
- A driver picked last time goes back in and can be picked again.
- Each driver picked must be tested during that selection period (382.305(i)(3)).
Unannounced and spread through the year
Random tests must be unannounced (382.305(k)(1)). Drivers should not get a heads-up that testing is coming.
Test dates must also be spread reasonably throughout the calendar year (382.305(k)(2)). Doing all your random tests in December to catch up is not a reasonable spread.
Once a driver is notified
When you tell a driver he or she was picked, the driver must go to the test site immediately (382.305(l)). If the driver is doing safety-sensitive work other than driving at that moment, the driver stops that work and goes as soon as possible.
Random alcohol tests have one more limit. They can only happen while the driver is doing safety-sensitive work, just before, or just after (382.305(m)).
Failing to show up for a test within a reasonable time after being told to go is a refusal to test under 40.191(a)(1). For owner-operators, this includes not showing up when called by a C/TPA.
Figuring your pool size
The testing rate is based on the average number of driver positions. Under 382.305(j)(1), add up the number of covered drivers in the pool at each selection period for the year, then divide by the number of selection periods.
For example, if you select quarterly and had 4, 6, 5, and 5 drivers, your average is 20 divided by 4, or 5 drivers.
Random selection records to keep
Section 382.401(c)(1)(ii) lists documents relating to the random selection process as records you must keep. They fall under collection-process records, which must be kept for at least 2 years (382.401(b)(2)).
Records must be kept in a secure place with controlled access. If FMCSA asks, you must make them available at your principal place of business within two business days (382.401(d)).
Pact Compliance runs random selections for small fleets and owner-operators in its consortium pool and keeps the selection records.
Common questions
Can the same driver be picked for random testing twice in a year?
Yes. Under 382.305(i)(2), every driver must have an equal chance of being picked each time selections are made. A driver who was just tested stays in the pool.
Can I tell my driver a day ahead that he has a random test?
No. Random tests must be unannounced (382.305(k)(1)), and a driver who is notified must go to the test site immediately (382.305(l)).
Can I use a consortium for random selection?
Yes. Under 382.305(j)(2), you can use a service agent such as a C/TPA, and your drivers can be in a larger pool. You must still make sure the pool is tested at the required rate and only holds covered employees.
What if a selected driver is on vacation?
The rule says each driver selected must be tested during the selection period (382.305(i)(3)). If the driver is available later in that same period, test the driver then.
How long do I keep random selection records?
382.401 lists random selection documents with collection-process records, which must be kept for at least 2 years.