The annual cost of substance abuse in the US measures in the billions, with workplace safety, loss of productivity and absenteeism being the biggest issues for employers. As a result, many companies rely on drug tests to prevent and deter drug and alcohol abuse. When you go through the job search process, you may find that in addition to the expected application and interview process, you might also be required to go through a pre-employment drug screening. If you are not sure what that entails, check out the FAQs below.

When Are Drug Tests Required?

When you're pursuing opportunities in certain fields -- for example, federal positions where safety is a priority -- you will be required to take a drug test before you are offered a job and during certain times after being hired. Federally mandated, safety-sensitive workers are those involved in the operation of any vehicle, including trucks, buses, airplanes, as well as those working in safety-sensitive environments such as nuclear plants.

In general, the top ten industries that require pre-employment drug testing include government, health care, manufacturing, automotive, transportation, private security, aerospace and defense, construction, information technology, and education. Most of those also require regular screenings while you are employed since intoxication in the workplace could result in accidents and injury, especially when the industry and occupation are already hazardous.

What Type of Drug Test Will I Need to Take?

Because of its ease of use and accuracy of results, a urine screen is the most commonly used drug test in the US, and the one you are most likely to encounter as a job candidate. Other tests include those relying on the collection of saliva, hair, sweat or blood samples. It's worth keeping in mind that drug screening doesn't always test for immediate or recent use, and many variables impact how long a drug stays in your system. For example, a urine sample can show traces of drugs days or weeks after use, a hair sample can show traces of drugs up to 90 days following use, and blood tests measure the presence of alcohol or drugs at the time a sample is drawn.

Drug tests also differ depending on how and why they are used by employers. Pre-employment drug tests take place during the candidate review process, and employers must require all candidates to take the test before being hired. Employers may also choose drug testing for current employees in one of the following situations:

• For-cause and reasonable suspicion testing: When an employee shows signs of impaired or unsafe behavior or there are issues with performance and absenteeism.
• Post-accident testing: When an employee is involved in a workplace accident.
• Post-treatment testing: When an employee returns to work following a treatment program.

What Are the Tests Screening to Find?

Most drug screens look for both legal and illegal substances that have the potential to be abused and to impact employees' safety, performance and productivity. Those include both street drugs and prescription drugs. The most commonly-used test in the US is the five-panel drug test, which requires a urine sample and screens for opiates (e.g. heroin and morphine), marijuana, amphetamines, PCP and cocaine.

Will Prescription Drugs Prevent Me From Being Hired?

When the test screens for them, certain prescription drugs can show up on a drug test. If this happens, you won't automatically be dismissed as a potential hire. Rather, the employer may investigate further to confirm that you have a medical reason and a prescription for the drug. However, if you're applying for occupations in industries that require or mandate a drug-free work environment, taking prescription drugs may reduce your chances of being hired. What happens depends on many variables, and to fully prepare, you may want to carefully research the field, role and company you are going into and pay attention to drug use policies.

What Happens After I Take a Drug Test?

The result of a drug test could be negative, inconclusive or positive. An inconclusive result means that you will either need to take another test or have the lab run the test again. A positive result suggests that you have used a substance in the past that's being screened. What happens when you test positive depends on employer policy and the state where you live. You may be removed from the qualified pool of candidates (or your role if already an employee) or you may be asked to provide additional information to prove you have a valid medical reason to use a specific drug.

Certain anti-discrimination and privacy laws may be on your side, but keep in mind that those don't give you permission to work under the influence. It's up to the employer to decide if the use could impact the safety of the workplace and if that in turn can impact your employment status. If you believe that your result is a false positive and if you hold a federally-regulated, safety-sensitive role, you have the right to a second test by another lab certified by the US Department of Health and Human Services.

What Happens If I Refuse to Take the Test?

You certainly have the right to refuse a drug test, but doing so may come with serious consequences. If a job offer is contingent upon a pre-employment drug test, you will have to take and pass the test in order to be considered for the role, especially if drug screening is mandated by law. Researching your target occupation and industry ahead of time can help you avoid the situation of looking suspicious by refusing to take a drug test.

How Does Marijuana Legalization Impact Pre-Employment Drug Tests?

Recent years have seen a rapid increase in the number of states legalizing marijuana, and currently, 33 states have legalized it for medical use while 11 have legalized it for recreational use. It's not surprising, then, that the substance is the most commonly detected one by drug tests across different workforce populations. While positive tests for opiates have decreased, those for marijuana have increased, and since the substance is still illegal at the federal level, the issue has created quite the conundrum for employers and HR managers across industries. Though you may live in a state that has legalized the use of marijuana, the law doesn't prevent employers from creating policies prohibiting prospective and current employees from using the substance. Even if you are a person with a medical marijuana identification card (MMID), an employer with a strict drug-free workplace policy may refuse to hire you or may dismiss you as an employee.

In an attempt to address the issue, states with legalized marijuana have started to approve measures that seek to protect candidates. For example, in Maine, a law protects employees from being discriminated against for using marijuana outside their workplaces. Most recently, the City Council in New York City approved a ban on most employers from requiring job candidates to take a drug test for marijuana. Depending on the state where you live, therefore, you could be protected under a nondiscrimination law or an invasion of privacy law. That said, if you are suspected of working under the influence, the law may not be on your side.