How Drug Tests Work

Understanding how the various forms of pre-employment, random, and court-ordered tests are administered, and how they work, can help everyone in the workplace and in the legal system.

Pre-Employment Drug Testing

Many employers codify the practice of drug testing policies and procedures in their workplaces.

Usually, employees and staff must agree to submit to a pre-employment drug test, and then further agree to random drug screening for the rest of their employment. However, for legal reasons, employers must have some documented and legitimate suspicion regarding an employee’s drug use before requiring their workforce to submit to random drug testing.

It is the responsibility of employers to create a written policy for enforcing and maintaining a “drug-free workplace,” which provides both employer and employee with legal protection. The policy must be available to the employees at all times.

Before employment actually begins, incoming workers must sign and date a copy of a document that provides legal proof that they have read the terms of creating a drug-free workplace, and that they have understood and agreed to it. The document can then be placed in their personnel file. A number of states have laws that require employers to do this in order to remain compliant with state laws.

The policy has to clearly state that the offer of employment is contingent upon the new hire passing a drug test. Help-wanted postings (both in print, online, and other forms of media) have to clarify that all new hires are equally subject to standardized drug testing.

To remain in compliance with state laws, employers must issue random drug tests to at least half their workforce every year. This is usually done by selecting and screening a percentage of the workforce once a month. Depending on the size of the office and the nature of the job, some companies do this every week.

Reasonable Suspicion

Reasonable suspicion” for a workplace drug test is defined as an employee behaving in an unnatural and uncharacteristic way, acting violent or erratic toward coworkers and management, and physical signs of substance abuse that are directly affecting job performance. The employee should be made aware that they will be subject to a drug test (per the guidelines in the employee handbook) to ensure the well-being of other employees and to maintain the nature of the drug-free workplace.

Every potential employee has to be administered a pre-employment drug test. A potential employee who returns a positive test result will not be eligible for the job anymore, no matter how qualified they were during the application process or how good they would be for the role. In order to maintain a drug-free workplace, failure of a pre-employment drug test is grounds for automatic non-consideration for the position.

Some fields require mandatory drug tests, or drug testing to a greater degree, than other businesses. For example, industries that are regulated by the Department of Transportation are subject to federal and state drug testing rules, which can be much more stringent than those in the private sector.

One of the caveats of random drug screening is that they have to be applied consistently to all employees. Management cannot selectively test some applicants and pass over others. The testing has to be done to everyone who receives the offer of a job.

Court-Ordered Drug Testing

When a court orders a person to undergo random drug testing, they usually give the person a choice of centers to choose from based on location and accessibility. The court will determine the frequency and the length of time that the person must undergo the testing (for example, one drug test a week for six months), but to randomize the process, the courts will not tell the person how often the testing will take place. The only guaranteed way to pass the tests is to refrain from drug consumption.

When a person enrolls in a testing center’s program, they will be assigned to a group. On the day of the testing, the center will announce which groups have to report for testing. If the person’s particular group is up for testing, everyone in that group will have to be there. The only way to find out is to call the testing center every day, first thing in the morning, to find out which group is scheduled. The center will not call clients.

Some centers also have websites, or text and email alerts, to let a person know that any given day is the day of their test.

Failing to show up for a court-ordered drug test will have serious consequences, such as loss of probation and a harsher sentence.

Testing centers arrange their schedules in such a way that people can never anticipate when their testing group will be called.

Field Sobriety Tests

A field sobriety test is usually administered by law enforcement if they believe that a person is intoxicated in a setting where being intoxicated breaks the law. The most common and obvious example is police testing a person for suspected drunk driving. Police administer field sobriety tests to evaluate a driver’s balance, their coordination, and their ability to multitask and divide their attention.

Drivers will have to maintain their horizontal gaze to smoothly follow an object with their eyes, walk heel-to-toe on a straight line and turn on one foot and repeat the process, and stand on one leg for 30 seconds without hopping to keep their balance, putting their foot down, or otherwise unduly struggling.

All these tests have been proven to show legal intoxication in drivers by the National Highway Traffic Safety Administration, and they are admissible as evidence of drunk driving in court.

A driver does have the right to refuse a field sobriety test, but this has its own consequences (which might even entail arrest). A driver who fails any one of the field sobriety tests will be given a breathalyzer test to assess their blood alcohol content, which can determine the level of the charge against them for drunk driving.

Types of Drug Tests

A blood drug test is one way of testing for illegal drugs when applicants or employees are tested. Such a test measures the amount of alcohol or drugs in the person’s blood at the time the blood is taken. Examples of the kinds of drugs that are screened in this type of test include opioids, alcohol, nicotine, marijuana, methamphetamines, and cocaine.

Breathalyzer tests are drug tests administered by breath alcohol testing devices. Breathalyzer refers to one such type of device that has become synonymous with this form of testing. They measure the presence and content of alcohol in the person’s blood.

Breath alcohol tests cannot be used to determine a person’s past alcohol use, only their level of impairment and intoxication at the time the test is given. In most cases, it takes one hour to metabolize one ounce of alcohol in a person’s system.

Oral and Hair Tests

A mouth swab test is also known as an oral fluids test or a saliva test. These collect saliva from the inside of the employee’s mouth, and they can show use of drugs in the previous few hours, up to the last couple of days.

Employers tend to prefer mouth swab tests because saliva is fairly easy to collect and test. For employees, this is a simple and less invasive form of drug testing.

A hair test, also known as hair follicle drug testing, does not indicate current drug impairment, but it can show drug use within the past 90 days. It does not show alcohol use, but it can determine the use of certain hallucinogens, methamphetamine, opioids, cocaine, and marijuana.

To administer a hair test, a drug technician will remove 100 strands of hair close to the scalp. Washing, dying, or styling the hair with consumer products will not affect the accuracy of the tests.

Urine Tests

The most commonly administered drug test for job applicants and employees is the urine test. An analysis of the urine will show the residual presence of drugs and alcohol, even after their effects have worn off. Many employers will require that applicants and current employees subject to pre-employment and random urine drug tests, for the purposes of establishing the use (or lack thereof) of drugs, including amphetamines, alcohol, cocaine, marijuana, nicotine, and opioids.

Urine tests use cutoff levels, where the result will only be positive if the traces of a drug are above a certain level. Notwithstanding this, urine tests can occasionally return false positive results (suggesting that a person has taken a drug when, in reality, they haven’t). Eating certain foods that contain the chemical compounds used in prescription or illicit drugs can cause a person to fail a drug test. Eating poppy seeds, for example, can technically throw up a red flag for suspected opioid use.

Diluted urine can also obscure the chemical traces of drugs in a urine sample.

Urine tests are still very reliable. They are considered the gold standard of drug tests in most applications and contexts.

The Detox Process

Detoxing from drugs and alcohol is the first step toward long-term recovery. It is also a complicated and potentially dangerous experience, so it should not be done without medical supervision, in a controlled environment (like a hospital or detox facility).

The process begins with a complete evaluation from a doctor to determine the extent of the patient’s drug consumption, getting a full inventory of how many drugs are involved, the dosage, and the length of time the drugs were taken. The doctor will also assess if there are any other medical conditions the patient has and if there is a family history of substance abuse or mental illness.

This knowledge will help plot out the course of drug detox. Doctors and staff will know which anti-anxiety, anticonvulsant, and antiemetic drugs (to prevent nausea and vomiting) can be safely administered without negatively interacting with other chemicals in the patient’s systems or unwittingly triggering an episode of mental illness.

Depending on the nature and extent of the drug abuse, and how quickly the detox process started, patients usually need a week or so to break the physical hold of the drugs. This can be much longer in cases of chronic abuse.

Completing detox is only part of the treatment process. The next step is receiving psychological care to address the mental health fallout of the substance abuse, as well as group therapy sessions that will help the patient learn to live without the need for alcohol or drugs. Some parts of this process can last a few months. Other parts of the process can be a lifelong effort to stay sober and healthy.

Generally speaking, the sooner the detox process is initiated, the smoother the recovery from the physical and psychological damage of drug use will be. It will also increase the chances of better coping with the inevitable struggles and challenges of recovery.

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