For many federal employees and employees of large-scale federal contractors, drug testing is a condition of employment. In some instances, such as for employees covered by the Omnibus Transportation Employee Testing Act of 1991 (hereinafter the Omnibus Testing Act), this testing is mandatory. In other cases, the testing is voluntarily included as part of the employer’s drug-free workplace program.

Some private employers also require drug and alcohol testing as a part of their drug-free workplace efforts. Often the reasons for testing include a concern for employee and customer safety. Employers have good reason for concern. Collecting data from several sources, including the U.S. Department of Labor, Statistic Brain reports that 65% of all job related accidents are drug or alcohol related.

Are There Rules About How and When an Employee Can Be Tested for Drug or Alcohol Use?

How and when an employee can be tested for drug use may depend on where the employee works and what job he or she performs, such as a safety-sensitive position.

Employees covered by the Omnibus Testing Act are subject to testing pursuant to the federal Department of Transportation’s (DOT) rules. Each agency within the Department of Transportation has specific guidelines for employees within that agency. These rules will indicate which employees must be tested and under what circumstances. A list of resources related to each agency’s rules can be found on the DOT’s Transportation.gov website. (Learn more in "DOT vs. Non DOT Testing: What's the Difference?")

Additionally, all testing for federal employees and certain employees of federal contractors must be conducted in compliance with the technical guidelines from the Substance Abuse and Mental Health Services Administration (SAMHSA), a division of the Department Health and Human Services.

Also adding to requirements of federal laws regarding employee drug and alcohol testing are the various state laws. These laws may limit or restrict the circumstances under which drug or alcohol testing may be conducted in workplaces not covered by the Omnibus Testing Act or other federal laws. (Learn more in "Medical Marijuana Law Differences and Contradictions".)

When Does Drug or Alcohol Testing Usually Take Place?

Statistic Brain reports that 56% of U.S. employers conduct pre-employment drug tests. Additionally, 29% of private employers conduct random drug screenings of employees.

Free Download: What Your Company's Drug and Alcohol Policy May Be Missing (and How to Get It Right)


For federal covered employees, the DOT’s Office of Drug and Alcohol Policy and Compliance employee information booklet, What Employees Need to Know About DOT Drug & Alcohol Testing, states that individuals may be tested prior to employment, when there is reasonable suspicion or cause to suspect drug or alcohol use, or when randomly selected as part of a required testing program. (Learn more in "8 Things Employers Should Know About DOT Drug and Alcohol Testing".) Additionally, an employee may be required to undergo testing prior to a return-to-duty following a violation of the employer’s drug or alcohol policy and throughout a follow-up period as determined by the employee's substance abuse professional (SAP). Finally, drug testing may be required following an on the job accident or near-miss.

While many of these circumstances may seem self-explanatory, determining when to test an employee for cause or reasonable suspicion can be complicated. In this article, we’ll take a closer look at how federal agencies define reasonable suspicion in the context of drug or alcohol testing.

DOT Testing For Cause or Reasonable Suspicion

While the Omnibus Testing Act authorizes DOT testing, the specific requirements for each DOT agency are included in that agencies regulations. As explained in this Federal Transit Administration (FTA) newsletter discussing the Use of Video Cameras in Reasonable Suspicion Determinations, only supervisors or other employer representatives who have undergone specific training to identify the signs of drug or alcohol misuse are allowed to make a reasonable suspicion determination.

Copies of the FTA’s reasonable suspicion training guide and video are available for download at the Federal Transit Administration website.

Each agency’s regulations also define the basis for reasonable suspicion. For example, the Federal Motor Carrier Safety Administration’s (FMCSA) reasonable suspicion provision is found in its regulations governing controlled substances and alcohol use and testing. Title 49, Part 382.307 of the regulations state that reasonable suspicion must be based on a “specific, contemporaneous, articulable observations” that indicates potential drug or alcohol use by an employee before testing may be required.

FMCSA’s regulations state that indications of alcohol use may include observations about the employee’s appearance, behavior, speech or body odor. For suspected drug use, signs of chronic use (such as track marks) or withdrawal may also justify a reasonable suspicion. The same or substantially similar definition is found in the regulatory text of other DOT agencies such as the Federal Railroad Administration and the Pipeline and Hazardous Materials Safety Administration.

Who Has to Observe Concerning Behavior?

First, to justify a request for an employee to take a drug or alcohol test, a supervisor must observe the conditions supporting that request. This requirement means that a decision based on information provided by another employee or co-worker is not sufficient to support a for cause request. The supervisor must personally witness the behavior, appearance, odor, or speech. In some instances, agency rules may require two supervisors to concur before a determination can be made.

Because of the serious consequences associated with requiring an employee to submit to for cause drug testing, observation of the signs of substance abuse alone does not constitute reasonable suspicion. As the regulations indicate, a supervisor’s observations must be specific, contemporaneous, and articulable.

What Does “Specific, Contemporaneous, and Articulable” Mean?

The qualifiers found in the regulations limit when a supervisor may refer an employee for drug or alcohol testing. Even if an employee’s co-workers are certain that the individual is using prohibited substances, the supervisor must satisfy these requirements to order drug or alcohol testing.

The requirement that an observation be specific means that an authorized official cannot act on a vague feeling or hunch. Instead, he or she must be able to point to specific signs of alcohol or drug abuse as the basis of the suspicion. In particular, supervisors should be able to indicate one or more of the indicators of substance abuse taught during their reasonable suspicion training.

In addition, any observation must be contemporaneous. In a brief summary titled "For-cause and Reasonable Suspicion Tests" on the SAMHSA website, the agency identifies testing as for cause when a supervisor notices “discernible signs” that an employee is unfit for duty and for reasonable suspicion when a supervisor has observed and documented a pattern of unsafe work behavior. A single observation may prompt a supervisor to order testing or the decision may be based on the cumulative effect of several observations.

However, regardless of the number of incidents observed, the request for testing must be made in a timely manner. A supervisor may not base a demand for testing today on information gathered several weeks ago.

Finally, the basis for suspicion must be articulable. The individual ordering drug or alcohol testing must be able to clearly state the reasons why he or she has done so. Usually, these reasons will be indicated on a checklist or form designed to ensure that the proper guidelines have been followed. For example, the Federal Aviation Administration uses a Reasonable Cause/ Reasonable Suspicion Documentation Form, while the Federal Transit Administration calls its form a Reasonable Suspicion Determination Report.

Knowing the Rules Protects Everyone

Workplace drug and alcohol testing as part of a workplace drug and alcohol policy is a key tool for maintaining a safe and drug-free workplace. Nonetheless, requiring an employee to submit to for cause testing can be a difficult decision to make. Apply the appropriate standards ensures that every employee is treated with respect while also ensuring everyone’s safety. (Learn more in "The Importance of a Good Drug and Alcohol Policy in the Workplace".)