• Employers are required to test drivers at minimum percentages, but may select a higher rate to ensure the company makes minimum testing rates by the end of the year.
• A scientific method must be used to select names at random.
• Employers can decide how often to test, but the DOT requires a minimum of quarterly selections.

Section 382.305(b) requires carriers to test at minimum percentages. Currently, motor carriers are required to have completed tests equal to at least 50 percent of the average number of drivers for drugs and 10 percent of the average number of drivers for alcohol. If the Federal Motor Carrier Safety Administration (FMCSA) revises the number of required annual tests, the revision for the coming year would be printed in the Federal Register by December.

A motor carrier may select a higher rate since the percentages in the regulations are minimums. Many carriers do this to make sure that the company makes the minimum percentages by the end of the calendar year.

For example, a canceled random drug or alcohol test may not be used in the annual total of completed tests. If a motor carrier has canceled or missed tests for a variety of reasons, the employer may elect to test at a higher rate throughout the year to meet the numbers without any adjustments.

Scientific method

The names must be selected using a scientifically valid method, such as a random number table or a computer-based random number generator that is matched to a number associated with the driver (e.g., Social Security Number, employee ID number, driver’s license number, etc.). Each driver must have an equal chance of being selected each time. The person’s name must remain in the driver list each testing cycle even if the person was selected previously during the year. In theory, the same person could be selected each time the motor carrier does a random selection.

Testing periods

Some carriers are left speculating how often the company should test. The decision is left up to the motor carrier. However, Department of Transportation (DOT) reference materials suggest that the agency expects to see at least quarterly selections, even though this requirement does not appear in regulatory text. The company will have to decide what schedule meets its needs. The only requirements are that the year is evenly broken up and the tests are completed within the testing period.

For example, if a motor carrier opts to test monthly, it will select fewer names, but the tests must be completed in shorter period of time. The motor carrier will have to decide whether this is feasible based on scheduling. If an employer instead selects quarterly draws, it will have more time to accomplish the tests, but the number of tests to complete will be greater. Again, the employer will have to look at its operation to determine what cycle is a fit.

An alternative for employers with relatively few drivers is to join a consortium with testing pools large enough so that drivers are always subject to random testing.

Determining the average number of drivers

Fluctuations in employment can skew random numbers if not calculated correctly. The FMCSA testing regulations state that employers' completed tests must equal at least 50 percent (drug) and 10 percent (alcohol) of the average number of driver positions, not necessarily the total number of drivers that were hired, used, or otherwise employed over the course of the year.

For example, suppose a carrier has an average of 100 driver positions for the year, but (due to turnover) actually used or employed a total of 140 drivers during the year. The company would be expected to make random selections based on its average of 100 driver positions, and would have to complete 50 tests for drugs (not 70) and 10 tests for alcohol (not 14) by December 31. Some individuals may be tested more than once, and some not at all.

An employer conducting random testing more often than once per month (e.g., daily, weekly, bi-weekly) does not need to compute the total number of covered drivers rate more than on a once per month basis.