Interpreting Drug and Alcohol Test Results

How Hard Can It Be?

Drug and alcohol testing is commonly performed post incident and for cause (when there is a reasonable suspicion that a worker is under the influence)
Most often, alcohol is tested using a standard breathalyzer and results are either clearly above the allowable limit or not. If the results are above the allowable limit, the person is considered to have failed the test. The results of this test are unequivocal and can be relied upon as an indicator of the level of impairment for the individual being tested.

Drug testing is far more complex because of the number of possible drugs to be tested for and the inability to determine impairment with some. Generally, these tests are carried out using either urine or oral fluids, although analysis of hair is also used rarely, and direct testing of blood may be used in certain circumstances.

There are, essentially, 3 types of drugs of concern:

1. Legal recreational drugs (primarily cannabis and derivatives)
2. Illegal recreational drugs (such as Cocaine, psilocybin, Ecstasy etc.)
3. Legal prescription drugs (opioids, barbiturates, benzodiazepines, amphetamines etc.) which can be abused either intentionally (recreational use) or unintentionally (mistaken overdose)

These drugs are used by individuals either for medical purposes (to assist with pain management or other medically authorized reasons) or recreational ones (because they provide the user with a desired effect of making a person “high” in some way.

The use of these drugs either legally or illegally can pose serious risks to worker safety in safety sensitive jobs. The risks include, but are not limited to, impairment of judgement, decision-making skills, motor function, reaction time, etc. It is these risks that are the primary reason why employers implement Drug and Alcohol programs that normally include provisions for testing for the drugs’ presence in the worker’s system under different circumstances, such as:

1. Pre-access testing to determine whether potential employees could pose a risk in the workplace,
2. Post-incident testing as part of an incident investigation to determine whether impairment contributed to the incident,
3. “reasonable cause” testing to determine if a worker, who is exhibiting signs or symptoms of impairment in the opinion of a supervisor,
4. Random testing which is primarily used as a deterrent to the recreational use of drugs of abuse.

Test Results

When a worker is tested for potential drugs of abuse in their system there are basically 4 outcomes. They are:

1. Negative – the drugs tested for are below a standardized cutoff concentration and are, therefore not of concern,
2. Non-negative – drugs are detected using a point of collection test that indicates a possibility of levels above the standard cutoffs. These samples are normally sent for chromatographic analysis in an accredited laboratory to confirm whether the drug(s) tested for are above the accepted standard level(s),
3. Positive – these are the results provided by the laboratory that indicate the drug(s) tested for are clearly above the accepted standard level(s)
4. Medically-negative – these results are positive for the drugs tested for, but the worker has a valid prescription or authorization from a qualified medical professional and the levels are consistent with the therapeutic levels expected for their use. This determination is made by a qualified Medical Review Officer (MRO) after discussion with the worker and, potentially their medical professional. What is important to note about this classification is that the worker may have therapeutic levels that would put themselves or others at risk in safety sensitive positions. The employer must decide whether the worker poses an unacceptable risk in the workplace based on the work they perform. The employer may be required to accommodate the worker up to a level of undue hardship.

If you have any questions related to this article, please feel free to contact Fit For Work and we will be happy to assist

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