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
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:
employees from abusing alcohol and drugs
hiring individuals who use illegal drugs
able to identify early and appropriately refer employees who have drug
and/or alcohol problems
a safe workplace for employees
the general public and instill consumer confidence that employees are
- Comply with State laws or Federal regulations
- Benefit from Workers’ Compensation Premium Discount programs
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.
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
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”
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
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
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
- 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 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 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
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.
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.
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.
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.
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.
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
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:
(meth, speed, crank, ecstasy)
- THC (cannabinoids,
(heroin, opium, codeine, morphine)
(PCP, angel dust)
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.”
typical 8-Panel Test includes the above-mentioned substances plus:
butalbital, secobarbital, downers)
(tranquilizers like Valium, Librium, Xanax)
typical 10-Panel Test includes the 8-Panel Test plus:
(often used to treat heroin addiction)
can also be done for:
(LSD, mushrooms, mescaline, peyote)
(paint, glue, hairspray)
steroids (synthesized, muscle-building hormones)
(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
- Alcohol – 1
oz. for 1.5 hours
Amphetamines – 48 hours
Barbiturates – 2-10 days
Benzodiazepines – 2-3 weeks
- Cocaine –
Metabolite – less than 1 day
- Morphine –
- LSD – 8
- Marijuana –
casual use, 3-4 days; chronic use, several weeks
Methamphetamine – 2-3 days
- Methadone –
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
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
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.
Drug-Free Workplace Advisor helps employers develop customized
drug-free workplace policies (that may or may not including drug testing) by
reviewing the different components of a comprehensive
policy and then generating a written policy statement based on the user’s
responses to pre-set questions and statements. (An organization’s name and logo
can be incorporated and further modifications to the statement made if
desired.) If an organization already has a drug-free workplace policy in place,
this tool can be used to ensure it addresses all necessary issues. Because it
is important to understand and incorporate the various state and Federal
regulations that may apply, it is also recommended that legal consultation be
sought before commencing a drug testing program.
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
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