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The Worker's Guide to Pre-Employment Drug Testing

Rebecca Koenig

Why do companies use pre-employment drug testing? There are three circumstances in which workers encounter drug tests during the hiring process.

The first is when workers have applied for jobs subject to federally mandated safety testing. Some of those positions are government jobs, such as Customs and Border Patrol agents, while others are in private sector industries such as transportation and nuclear power production.

The second is when workers have applied for jobs subject to state-mandated safety testing.

The third is when workers are hoping to be hired at companies that elect to test for drugs for a variety of reasons. Some organizations participate in statewide drug-free workplace incentive programs. At others, drug use can be dangerous or costly.

"There might be a risk to the individual -- or the people they're caring for or serving could be hurt -- if they are impaired," says Phyllis G. Hartman, founder of PGHR Consulting and member of the Society for Human Resource Management HR Disciplines special expertise panel. Health care, child care and petrochemical industries commonly use pre-employment drug testing, she explains.

And still other companies use drug tests as part of their general background check procedures. Leaders at these companies rank candidate sobriety among "the criteria you believe will make them a successful and long-term employee of an organization," says Nina French, managing partner of the Current Consulting Group, an employee background screening consulting firm.

[READ: How to Break Into the Weed Industry: Everything You Need to Know.]

For which drugs do companies test?

Typical pre-employment drug screenings test for:

-- Amphetamines.

-- Cocaine.

-- Marijuana.

-- Opiates.

-- Phencyclidine (PCP).

New federal rules have included additional prescription opioids to the list, and some private companies also test for other prescription drugs like barbiturates.

How do companies perform employment drug testing?

Companies test for drugs using three main specimen types: urine, hair and oral fluid. Each one has different detection windows, advantages and disadvantages.

Urine is the most common sample type, and it's currently the only type permitted by federal testing rules, says Barry Sample, senior director of science and technology at Quest Diagnostics, a clinical laboratory that performs drug testing for employers.

One benefit the urine drug test has for workers is that it's conducted privately. It's also good for employers, Sample explains: "Generally, urine testing offers the broadest menu of drugs that can be tested for."

Oral fluid and hair are collected in public. Some workers find hair drug tests to be unpleasantly invasive, since testers trim their hair, Sample notes. And instead of registering recent drug use, Sample says, "hair detects a pattern of repetitive use. It reflects a lifestyle."

[SEE: What You Need to Know About Getting a Security Clearance.]

When does a drug test for a job take place?

Many employers that require drug tests tell candidates in advance, Hartman says. This kind of heads up may save companies time and money and prevent workers from embarrassment, since it affords those likely to fail an opportunity to bow out ahead of time.

Some employers will administer drug tests before making job offers, but many only issue drug tests after job offers are made. Some states require offers to come first, Hartman says.

Do workers know how to cheat a drug test?

Drug tests include measures designed to thwart manipulation, French says: "Employers and labs are pretty savvy about that."

For urine tests, job candidates typically must remove outer garments, empty their pockets and leave behind purses and bags before stepping into collection rooms. A testing agent may stand by the door to listen "to ensure it sounds like there's normal sounds of providing a sample," Sample says. Specimen testers measure the temperature of urine samples within four minutes of collection.

Some candidates may be tempted to thwart hair tests by shaving their entire bodies, but that act "is often deemed a refusal to test," French says.

As for oral fluid tests, they are "much, much more difficult to adulterate," French says. "Oral fluid replenishes rapidly."

Can a legitimate medical prescription lead to a failed drug test?

Many employers use the services of a medical review officer to ensure that people who take legitimately prescribed drugs are still eligible for jobs. When an officer encounters a non-negative test result, he or she contacts the test subject and asks whether there's a medical explanation. The officer then checks with the subject's pharmacy or physician.

"They're not assessing whether or not the drug is being used as prescribed or whether the prescription is appropriate," Sample explains. "It's a paper exercise to determine whether or not there's a valid prescription."

Having medical review officers perform these checks helps to ensure that employers don't learn about job applicants' private health information.

[READ: To Pass a Personality Test, Use Your Professional Persona.]

What happens if you fail a pre-employment drug screening?

In many cases, job candidates who fail drug tests and who lack legitimate prescriptions will simply be told that they've failed and that they're no longer eligible for the employment opportunity. They may be able to reapply at the company after six months or a year, French says.

There are a few industries where a failed drug test has more serious, lasting career implications, however. For example, the Federal Motor Carrier Safety Administration is creating a clearinghouse for failed test results. It's designed to prevent a truck driver who fails or refuses a drug test at one company from obtaining employment at another without satisfying additional requirements.

How do marijuana legalization laws affect pre-employment drug testing?

Laws in some states making marijuana legal for medical or recreational use have complicated pre-employment drug testing policies and practices. So has the growing popularity of CBD oil in all kinds of consumer products.

"It is a hot mess," French says. "It puts everybody in a horrible position."

Marijuana remains illegal on a federal level, so it's still cause for failure on federally mandated safety tests. Neither cannabis nor CBD oil is currently strictly regulated by the Food and Drug Administration, so it's hard for users to know for sure how much psychoactive material they're consuming and whether it will affect their drug screenings. Pharmacies don't fulfill prescriptions for medical marijuana, so medical review officers can't distinguish between legitimate and illegitimate use.

"Generally there are not explicit employee protections for either recreational or medical marijuana use," Sample says.

Attitudes toward marijuana use may be slowly changing at companies that have the leeway to decide whether to test for it, though. In Washington and Colorado, two states where recreational use is legal, voluntary testing of marijuana decreased from 99% in 2015 to 95% in 2018 among clients of Quest Diagnostics. In Nevada, it decreased from 96.5% in 2015 to 88.5% in 2018.

But as long as the legal status of marijuana remains ambiguous, it's safer from a career standpoint to abstain, experts say.

"You're putting your ability to get the job at risk by using it for any reason," French says.

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