Drug testing is one action an employer can take to determine if employees or job applicants are using drugs. It can identify evidence of recent use of alcohol, prescription drugs and illicit drugs. Currently, drug testing does not test for impairment or whether a person’s behavior is, or was, impacted by drugs. Drug testing works best when implemented based on a clear, written policy that is shared with all employees, along with employee education about the dangers of alcohol and drug abuse, supervisor training on the signs and symptoms of alcohol and drug abuse, and an Employee Assistance Program (EAP) to provide help for employees who may have an alcohol or drug problem.
Why do employers drug test?
Alcohol and drug abuse creates significant safety and health hazards and can result in decreased productivity and poor employee morale. It also can lead to additional costs in the form of health care claims, especially short-term disability claims.
Common reasons employers implement drug testing are to:
- Deter employees from abusing alcohol and drugs
- Prevent hiring individuals who use illegal drugs
- Be able to identify early and appropriately refer employees who have drug and/or alcohol problems
- Provide a safe workplace for employees
- Protect the general public and instill consumer confidence that employees are working safely
- Comply with State laws or Federal regulations
How is drug testing conducted and how accurate is it?
Generally, most private employers have a fair amount of latitude in implementing drug testing as they see fit for their organization, unless they are subject to certain Federal regulations, such as the U.S. Department of Transportation’s (DOT) drug-testing rules for employees in safety-sensitive positions. However, Federal agencies conducting drug testing must follow standardized procedures established by the Substance Abuse and Mental Health Services Administration (SAMHSA), part of the U.S. Department of Health and Human Services (DHHS).
While private employers are not required to follow these guidelines, doing so can help them stay on safe legal ground. Court decisions have supported following these guidelines, and as a result, many employers choose to follow them. These Mandatory Guidelines for Federal Workplace Drug Testing (also called SAMHSA’s guidelines) include having a Medical Review Officer (MRO) evaluate tests. They also identify the five substances tested for in Federal drug-testing programs and require the use of drug labs certified by SAMHSA.
The most common method of drug testing, urinalysis, can be done at the workplace (at a health unit, for example), a doctor’s office or any other site selected by the employer. An employee or applicant provides a sample to be tested. Usually precautions are taken, such as putting blue dye in the toilet and turning off the water supply, to prevent adulteration or substitution of specimens so that collection can be completed in privacy without any direct visual observation by another person.
Under SAMHSA’s guidelines, once a sample is provided, it is sent to a certified laboratory. The accuracy of drug tests done by certified laboratories is very high, but this certification applies only to the five substances tested for in Federal drug-testing programs and alcohol.
Below are certain procedures required by SAMHSA’s guidelines to ensure accuracy and validity of the testing process:
- Chain of Custody: A chain-of-custody form is used to document the handling and storage of a sample from the time it is collected until the time it is disposed. It links an individual to his or her sample and is written proof of all that happens to the specimen while at the collection site and the laboratory.
- Initial Screen: The first analysis done on a sample is called an initial screen. This one test alone is not always accurate or reliable; there is a possibility of a false positive. Thus, in the event that the initial screen is positive, a second confirmatory test should be done.
- Confirmation Test: A second, confirmation test (by gas chromatography/mass spectrometry or GC/MS) is highly accurate and provides specificity to help rule out any false positives (mistakes) from the initial screen. For a test result to be reported as positive, the initial screen and confirmation test results must agree.
- Split Sample: A split sample is created when an initial urine sample is split into two. One sample is used for the initial screen and, if positive, the second sample is used for the confirmation test. If there is a positive result, the individual being tested may request the confirmation test be done at a different laboratory. DOT's alcohol and drug-testing regulations require all tests be performed using a "split sample” collection process.
In the event that the initial screen and confirmation test are both positive, MRO, a licensed medical doctor who has special training in the area of substance abuse, then reviews the results, makes sure the chain-of-custody procedures were followed, and contacts the individual to make sure there are no medical or other reasons for the result. It is only at this point that the MRO may report a positive test result to the employer. Certain medications can sometimes cause a positive result. If this is the case, and a doctor prescribed the medicine and the employee used it in the proper amount, the test is reported as negative.
Who is allowed access to the results of a drug test?
The result of a drug test may be considered personal health information. Consequently, there may be restrictions on how and whether such information (as well as other information related to an employee’s history of alcohol or drug use) can be shared with others. This is why employees who undergo a drug test generally must sign a release (usually at the time of the test) in order for their employer to receive the results. For more information about issues related to the release of health information, contact DHHS. This agency administers the Health Insurance Portability and Accountability Act (HIPAA), which dictates under what circumstances and to whom health information may be released. More information about this issue can be found on Office of Civil Rights HIPAA Web page.
When are drug tests conducted?
There are a variety of circumstances under which an organization may require a drug test. Following are the most common or widespread:
- Pre-Employment: Pre-employment testing is conducted to prevent hiring individuals who illegally use drugs. It typically takes place after a conditional offer of employment has been made. Applicants agree to be tested as a condition of employment and are not hired if they fail to produce a negative test. However, it is possible for employees to prepare for a pre-employment test by stopping their drug use several days before they anticipate being tested. Therefore, some employers test probationary employees on an unannounced basis. Some states however, restrict this process. Furthermore, the Americans with Disabilities Act (ADA) of 1990 prohibits the use of pre-employment testing for alcohol use.
- Reasonable Suspicion: Reasonable suspicion testing is similar to, and sometimes referred to, as "probable-cause” or "for-cause” testing and is conducted when supervisors document observable signs and symptoms that lead them to suspect drug use or a drug-free workplace policy violation. It is extremely important to have clear, consistent definitions of what behavior justifies drug and alcohol testing and any suspicion should be corroborated by another supervisor or manager. Since this type of testing is at the discretion of management, it requires careful, comprehensive supervisor training. In addition, it is advised that employees who are suspected of drug use or a policy violation not return to work while awaiting the results of reasonable suspicion testing.
- Post-Accident: Since property damage or personal injury may result from accidents, testing following an accident can help determine whether drugs and/or alcohol were a factor. It is important to establish objective criteria that will trigger a post-accident test and how and by whom they will be determined and documented. Examples of criteria used by employers include: fatalities; injuries that require anyone to be removed from the scene for medical care; damage to vehicles or property above a specified monetary amount; and citations issued by the police. Although the results of a post-accident test determine drug use, a positive test result in and of itself can not prove that drug use caused an accident. When post-accident testing is conducted, it is a good idea for employers not to allow employees involved in any accident to return to work prior to or following the testing. Employers also need to have guidelines to specify how soon following an accident testing must occur so results are relevant. Substances remain in a person’s system for various amounts of time, and it is usually recommended that post-accident testing be done within 12 hours. Some employers expand the test trigger to incidents even if an accident or injury was averted and hence use term "post-incident.”
- Random: Random testing is performed on an unannounced, unpredictable basis on employees whose identifying information (e.g., social security number or employee number) has been placed in a testing pool from which a scientifically arbitrary selection is made. This selection is usually computer generated to ensure that it is indeed random and that each person of the workforce population has an equal chance of being selected for testing, regardless of whether that person was recently tested or not. Because this type of testing has no advance notice, it serves as a deterrent.
- Periodic: Periodic testing is usually scheduled in advance and uniformly administered. Some employers use it on an annual basis, especially if physicals are required for the job. Such tests generally are more accepted by employees than unannounced tests, but employees can prepare them by stopping their drug use several days beforehand.
- Return-to-Duty: Return-to-duty testing involves a one-time, announced test when an employee who has tested positive has completed the required treatment for substance abuse and is ready to return to the workplace. Some employers also use this type of testing for any employee who has been absent for an extended period of time.
- Other: Other types of tests are also used by some employers. For example, follow-up testing or post-rehabilitation testing is conducted periodically after an employee returns to the workplace upon completing rehabilitation for a drug or alcohol problem. It is administered on an unannounced, unpredictable basis for a period of time specified in the drug-free workplace policy. Another type of testing, blanket testing, is similar to random testing in that it is unannounced and not based on individual suspicion; however, everyone at a worksite is tested rather than a randomly selected percentage. Other types of testing include voluntary, probationary, pre-promotion and return-after-illness testing.
What are the different methods of drug testing?
There are a number of different bodily specimens that can be chemically tested to detect evidence of recent drug use. Although some state laws dictate which types of tests can be used, a number of options are technologically feasible. Urine is the most commonly used specimen for illicit drugs, reflecting SAMHSA’s guidelines, and breath is the most common for alcohol, reflecting DOT’s guidelines.
- Urine: Results of a urine test show the presence or absence of drug metabolites in a person’s urine. Metabolites are drug residues that remain in the body for some time after the effects of a drug have worn off. It is important to note that a positive urine test does not necessarily mean a person was under the influence of drugs at the time of the test. Rather, it detects and measures use of a particular drug within the previous few days and has become the defacto evidence of current use. Because alcohol passes rapidly through the system, urine tests must be conducted very quickly after alcohol consumption in order to ensure any degree of accuracy. For this reason, urine tests are generally not helpful in detecting alcohol use as opposed to illicit and prescription drug use, which is more easily traced in urine.
- Breath: A breath-alcohol test is the most common test for finding out how much alcohol is currently in the blood. The person being tested blows into a breath-alcohol device, and the results are given as a number, known as the Blood Alcohol Concentration (BAC), which shows the level of alcohol in the blood at the time the test was taken. BAC levels have been correlated with impairment, and the legal limit of 0.08 for driving has been set in all states. Under DOT regulations, a BAC of 0.02 is high enough to stop someone from performing a safety-sensitive task for a specific amount of time (usually between 8 and 24 hours) and a BAC reading of 0.04 or higher is considered to be a positive drug test and requires immediate removal from safety-sensitive functions. Under DOT regulations, a person who tests at the 0.04 BAC level may not resume job duties until a specific return-to-duty process has been successfully completed.
Other alternative specimens that can be used for detecting the use of selected drugs of abuse include blood, hair, oral fluids and sweat.
- Blood: A blood test measures the actual amount of alcohol or other drugs in the blood at the time of the test. Blood samples provide an accurate measure of the physiologically active drug present in a person at the time the sample is drawn. Although blood samples are a better indicator of recent consumption than urine samples, there is a lack of published data correlating blood levels for drugs and impairment with the same degree of certainty that has been established for alcohol. In cases of serious injury or death as the result of an accident, the only way to determine legal intoxication is through a blood specimen. There is also a very short detection period, as most drugs are quickly cleared from the blood and deposited into the urine.
- Hair: Analysis of hair provides a much longer "testing window,” giving a more complete drug-use history going back as far as 90 days. Like urine testing, hair testing does not provide evidence of current impairment, but rather only past use of a specific drug. Hair testing cannot be used to detect for alcohol use. Hair testing is the least invasive form of drug testing, therefore privacy issues are decreased.
- Oral Fluids: Saliva, or oral fluids, collected from the mouth also can be used to detect traces of drugs and alcohol. Oral fluids are easy to collect (a swab of the inner cheek is the most common collection method), harder to adulterate or substitute, and may be better at detecting specific substances, including marijuana, cocaine and amphetamines/methamphetamines. Because drugs do not remain in oral fluids as long as they do in urine, this method shows promise in determining current use and impairment.
- Sweat: Another type of drug test consists of a skin patch that measures drugs in sweat. The patch, which looks like a large adhesive bandage, is applied to the skin and worn for some length of time. A gas-permeable membrane on the patch protects the tested area from dirt and other contaminants. Although relatively easy to administer, this method has not been widely used in workplaces and is more often used to maintain compliance with probation and parole.
What drugs do tests detect?
Testing conducted according to SAMHSA’s guidelines checks for five illicit drugs plus, in some cases, alcohol (ethanol, ethyl alcohol, booze). These five illicit drugs are:
- Amphetamines (meth, speed, crank, ecstasy)
- THC (cannabinoids, marijuana, hash)
- Cocaine (coke, crack)
- Opiates (heroin, opium, codeine, morphine)
- Phencyclidine (PCP, angel dust)
However, most private employers are not limited in the number of substances they can test for and may include drugs that individuals legitimately and/or therapeutically take based on a physician’s prescription. Although most private employers can test for any combination of drugs, there are commonly selected "panels.”
The typical 8-Panel Test includes the above-mentioned substances plus:
- Barbiturates (phenobarbital, butalbital, secobarbital, downers)
- Benzodiazepines (tranquilizers like Valium, Librium, Xanax)
- Methaqualone (Quaaludes)
The typical 10-Panel Test includes the 8-Panel Test plus:
- Methadone (often used to treat heroin addiction)
- Propoxyphene (Darvon compounds)
Testing can also be done for:
- Hallucinogens (LSD, mushrooms, mescaline, peyote)
- Inhalants (paint, glue, hairspray)
- Anabolic steroids (synthesized, muscle-building hormones)
- Hydrocodone (prescription medication known as Lortab, Vicodin, Oxycodone)
- MDMA ( commonly known as Ecstasy)
How long are drugs in one’s system?
Drugs have certain "detection windows”—the amount of time after ingestion during which evidence of their use can be detected by a drug test. Though it might not be wise to publicize detection windows and invite employees who may use drugs to push their limits, when implementing drug testing, it is important to understand them. For instance, alcohol is absorbed and eliminated more quickly than other drugs. This is why post-accident testing procedures often require testing for alcohol to occur within two hours. Other drugs are eliminated from the system at different rates and thus detectable for different periods of time, often long after the drug's effect has worn off. The following are estimates of the length of time that certain drugs are detectable:
- Alcohol – 1 oz. for 1.5 hours
- Amphetamines – 48 hours
- Barbiturates – 2-10 days
- Benzodiazepines – 2-3 weeks
- Cocaine – 2-10 days
- Heroin Metabolite – less than 1 day
- Morphine – 2-3 days
- LSD – 8 hours
- Marijuana – casual use, 3-4 days; chronic use, several weeks
- Methamphetamine – 2-3 days
- Methadone – 2-3 days
- Phencyclidine (PCP) – 1 week
How does a drug test determine if a person has been using substances? What are cut-off levels and what do they determine?
Aside from a breath alcohol test, drug testing does not determine impairment or current drug use. Rather, drug testing determines a specified amount or presence of a drug or its metabolite in urine, blood or an alternative specimen. There is a minimum measurement applied to drug testing so that only traces of a drug or its metabolite above a specified level is reported as positive. This measure is known as a "cut-off level,” and it varies for each drug. Setting cut-off levels involves understanding the expected results of testing and determining the needs of the employer’s drug-free workplace program. For instance, if a cut-off level is set low, test results will come back with more "false positives” as some "passive” users could test positive. (For example, a low cut-off level could cause a positive result from consuming poppy seeds.) Conversely, a high cut-off level will result in more "false negatives,” and thus some users may go undetected. However, a high cut-off level lessens the likelihood of taking action against someone based on "passive” exposure, and for this reason SAMHSA’s guidelines set cut-off levels on the high side.
Other considerations when implementing drug testing
Who pays for a drug test? Does an employee have to be paid for time spent having a drug test?
According to SAMHSA, an employer normally pays for a drug test. Also, time spent having a required drug test is generally considered hours worked (and thus compensable time) under the Fair Labor Standards Act (FLSA), a U.S. Department of Labor (DOL) regulation, for employees who are covered by the Act. These types of issues are overseen by DOL’s Wage and Hour Division. For further guidance, please contact the closest DOL Wage and Hour District Office.
Is drug testing legal?
In most cases it is legal for employers to test employees for drugs. No Federal laws prohibit the practice. However, there are several states that restrict or question an employer’s ability to randomly drug test employees who are not in safety-sensitive positions. Thus, it is very important that employers familiarize themselves with the various state laws that may apply to their organization before implementing a drug-testing program. Furthermore, under certain circumstances, someone with a history of alcoholism or drug addiction may be considered a qualified individual with a disability under the Americans with Disabilities Act (ADA) and other Federal non-discrimination statues. As a result, testing for alcohol without individualized suspicions (e.g. pre-employment or random) is not allowable.
How does one start a drug-testing program?
Drug testing is only one component of a comprehensive drug-free workplace program, which also includes a written policy that clearly outlines employer expectations regarding drug use; training for supervisors on the signs and symptoms of drug use and their role in enforcing the policy; education for employees about the dangers of drug use; and an Employee Assistance Program (EAP) to provide counseling and referral to employees struggling with drug problems. DOL’s online A comprehensive drug-free workplace program contributes to a workplace free of the health, safety and productivity hazards caused by employees’ abuse of alcohol or drugs. By educating employees about the dangers of alcohol and drug abuse and encouraging individuals with related problems to seek help, employers can protect their businesses from such dangers, retain valuable employees and help play a part in making communities safer and healthier.
Other Drug-testing resources
In addition to DOL’s Working Partners Web site, the following resources may be helpful to organizations implementing workplace drug testing.