Drug Tests - Why Test and How Testing is Conducted

Why 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:

• Deter employees from abusing alcohol and drugs


• Prevent hiring individuals who use illegal drugs


• Be able to identify early and appropriately refer employees who have drug and/or alcohol problems


• Provide a safe workplace for employees


• Protect the general public and instill consumer confidence that employees are working safely


• Comply with State laws or Federal regulations


• Benefit from Workers' Compensation Premium Discount programs

Information above and throughout this document has been provided by the United States Department of Labor http://www.dol.gov/workingpartners/welcome.html

How screening is conducted?

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.

Initial 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 must agree.

Split 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" collection process.

MRO: 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.