Employee FAQ'S: Workplace Drug Testing

As a provider of drug testing services to workplaces and events, we often get asked questions about what the testing involves, if the testing is legal and what substances are detected.



Is it legal for my employer to drug test me? 

Yes, it is.  In fact, it is a legal obligation, as stated in the OHS Act, that employers must provide adequate ‘duty of care’ to employees in the workplace and this includes management of drug and alcohol issues.  However, employers should implement a drug and alcohol policy which explains their position on drugs and alcohol in the workplace as well as any procedures relating to testing and management of issues before commencing testing.

What drugs are tested for in workplaces?

This can depend on a few factors including what type of test being conducted, and what industry you work in.  But Standards Australia, the organisation that develops best practice guidelines for industry, specifies the following drug classes be included in workplace testing programs: Opiates, Amphetamines, Methamphetamine, Cocaine, Cannabis and sometimes, Benzodiazepines.

How long will the drug test take?

On-site drug screening tests are generally quick.   Saliva tests are non-invasive and easy to collect.  The process usually takes no more than 10-15 minutes.  Urine tests can take longer, especially if the donor can’t provide a sample on demand.  In this case, the tester will usually have the donor site aside until they are able to provide the sample.

What is informed consent?

Informed consent means that the process for the drug testing has been explained to the donor and the donor has agreed to undertake the test.  Informed consent should cover why the test is being carried out, the testing process, confidentiality of results and what happens if the result is positive.   

What if I take medication prescribed by my doctor?

Many medications have the potential to cause drowsiness or impaired performance.  It is important to have a confidential talk with your supervisor or health & safety manager if you are prescribed any medications that could cause issues, especially if you are working in safety sensitive areas like operating equipment or a vehicle.  Some medications could be detected in a drug test, such as pain killers or anti-anxiety medication.  Even if they aren’t, it’s important to have the conversation, as you may need to be moved to lighter duties, while taking the medication.

Can I refuse to do a drug test?

You could refuse, but it is not advisable.  Provided your employer has a drug and alcohol policy in place, refusing a test could result in a similar outcome to failing a test.  Many workplace policies implement disciplinary action upon refusal to complete a test, such as standing an employee down or issuing a warning.

What happens if my test comes back positive?

In the case of on-site screening, a positive test result is only the first step.  This is officially called a non-negative.   The screening provides an indication of the status of the employee and provides enough information to the employer to determine if the donor needs to be stood down from work to manage safety risks.  Best practice in the event of a non-negative test on-site, is that the sample must be re-tested in a laboratory.  This is called confirmation testing and is a highly specific and accurate method of testing which provides a definitive result.  The confirmation test uses a method like LC/MS which provides information about exactly what drug or drugs are present in the employee’s sample and at what level.

How long will drugs be detected in my system?

How long a drug can be detected by a drug test is called the window of detection. The exact amount of time drugs stay in your system depends on many factors including:  how much of the drug was taken, the purity of the drug, overall health, whether other drugs or alcohol are also in the system.  As a general guide, the window of detection for are:

Drug Group Saliva Urine
Opiates 24hrs 3 days
Amphetamines 24-36hrs 3-4 days
Methamphetamines 24-36hrs 3-4 days
Cocaine 12-24hrs 3-4 days
Cannabis 8-12hrs 3-30 days
Benzodiazepines up to 12 hrs (not slow release) up to 2 weeks
Oxycodone 24hrs 3 days


What about Cannabis?  Doesn’t it stay in your system for months after use?

Yes and no.  How long cannabis is detected in your system depends on a number of factors, namely, what type of test you are taking – saliva or urine – and how often you use the drug.   

In the case of saliva drug testing, it identifies the active form of cannabis (d-9 THC).  This active drug can be detected in saliva for less than 1 day.   However, in the case of a urine drug test, it identifies the cannabis metabolite, d9-THC-COOH.  This metabolite can be detected in urine for at least 4 days after use, and in cases where the drug is used regularly, the window of detection can extend to months after last use.

What if there is a false positive?

A screening test should not be considered 100% accurate.  It is called a presumptive test and provides an indication of the result.  Therefore occasionally, it is possible for the screening test to produce a false positive result.  Some reasons this can happen are because the test has cross reacted with another substance in the donor's sample, or because the drug level was very close to the cut-off.  It is always necessary to have the screening test confirmed in a laboratory, which will determine if the result was a false positive or a confirmed positive.  


Still have questions?  Email us at info@bmfhq.com.au


Workplace drug testing

Leave a comment

All comments are moderated before being published