There are 55 million employee drug tests submitted for analysis each year—over 90% of them are urine tests. That’s largely due to the fact that the urine drug test is the only approved method for employers regulated by the federal government.

Until recently anyway.

No longer the one and only

The HHS (U.S. Department of Health and Human Services) released oral fluid drug testing guidelines at the end of October. Beginning January 1, 2020, employers of the  safety-sensitive workforce and other federally mandated employees will be free to choose whether to continue with the urine drug test or switch to the oral fluid test.

Furthermore, the DOT officially requested changing from the urine drug test to the hair follicle drug test. It affords employers the advantage of a 90-day window of detection. Currently, the request is passing through the chain-of-command and expected to meet with approval at each stage of the process.

Even though it seems the DOT may eventually stop using the urine drug test, many employers use this drug test because it’s the most cost-effective method and, quite frankly, expected by employees upon hearing that a company drug tests.

They know what to expect

If someone hasn’t actually had to take a urine drug test, it’s more than likely that they know the drill.

Collection specialists greet the employee or prospect and complete the identification process. Next, the specialist explains the procedure in full and asks the person to remove any outer garments, such as coats or jackets, and to show the contents of their pockets or purse. The collection specialist provides the subject with a specimen cup and escorts them to the assigned restroom to collect the sample.

After collecting the required amount, about one and one-half ounces, the employee or prospect returns the sample to the specialist who measures and documents the temperature immediately.

If it fails to fall within the required range, it’s an immediate sign of tampering.

The employee or prospect then completes any custody and control paperwork to complete the testing process.

Lab tests

All urine samples undergo an initial screening process. The immunoassay (IA) test determines if drugs are present with a positive or negative response. The test is the most cost-effective test by far because the majority of drug tests are negative.

Tests that yield a positive result are sent for confirmation testing. The gas chromatography/mass spectrometry (GC/MS) test confirms the positive drug result by identifying the drug present and the detection level as well.

Employers receive test results within a few days.

Reading results

The results of a drug test are read as follows:

  • Positive—A positive result identifies drug use.
  • Negative—A negative result indicates no drug use.
  • Inconclusive—An inconclusive results concludes neither a positive nor negative result.

There are several reasons that a drug test returns with an inconclusive result.  Human error may have somehow played a part, although it’s a rare occurrence, the possibility remains. Evidence of tampering or substitution warrants an inconclusive test result, one way drug users attempt to falsify the test results is to “cleanse” drug metabolites form the system by drinking lots of water.

It’s possible for urine to become so diluted by excessive fluid intake that it throws off the natural balance of creatinine levels in the urine. When these levels are off it alerts lab technicians that the specimen has been diluted.

Dilute results

When a test sample is diluted, but there are drugs identified as well, the result is deemed a positive dilute. Because there is definite drug identification, employers proceed with company protocol pertaining to a positive test result.

A negative dilute, on the other hand, doesn’t identify any drugs in the system. However, the fact that a urine sample is diluted indicates to an employer someone may have been trying to mask drug use. Some employers conduct a second test. However, it better be a negative result. There won’t be a third attempt.

Detection periods

The urine test can identify all manner of drugs in the system.

The length of the identification period varies from a few hours after ingestion to days or weeks after discontinuing use. Several factors play in to the length of time that drug tests can identify drugs in the system.

Drug specific

The amount of time that drug metabolites remain in the system depends largely on the drug itself. Furthermore, drug tests identify different types of the same drug for various periods of time. For instance, extended release tabs take longer to make their way through the system.

Dosage and frequency

It stands to reason that the amount of the drug ingested and the number of times its used effects the detection period.

Genetically speaking

Our DNA is what makes us unique. Our DNA make-up determines the amount of time that it takes the body to complete the metabolization process.


Young people tend to metabolize things more quickly than older adults.

Body mass

Drug metabolites store themselves throughout the body awaiting excretion. Metabolites stored in the fat cells may take longer to cleanse if someone is overweight. Comparatively, someone who is lean probably excretes the metabolites sooner.

The reason employers drug test

There’s no doubt that drug use in the workplace is a huge safety hazard. Employees who use drugs may have a distorted sense of time and space, impaired motor skills, and be unable to maintain focus on the task at hand.

They’re not only putting themselves at increased risk of an accident, but everyone else around them is at risk as well.

Employers want to keep drugs out of the workplace for safety’s sake. They are responsible for the well-being of each and every employee.

That includes the drug abuser.

If an employee pops positive on a drug test, expressing concern for their well-being can be a ray of light on a very dark day. Realizing that your drug use has caused you to lose your job can put you at a big fork on the road of life.

The path chosen from that moment on is going to be life changing either way.