Drug testing for employment

Pre-employment or on-the-job drug and alcohol testing

Key points about drug testing for employment  

  • Some businesses and employers might have workplace policies that include drug and alcohol testing or you might need to be tested before you are employed.
  • The employment policy should outline what is (and what isn’t) included, and what happens if you choose not to do it. 
  • Generally, an employer can only ask you to take a drug or alcohol test if it’s: 
    • part of their health and safety policy 
    • a condition of your employment 
    • in your employment agreement. 
  • This page has information about pre-employment and employment drug testing, how to prepare for it and what to expect. 
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The main reasons employers test their workers for drugs and alcohol use are to prevent potentially harmful situations and keep their employees safe. Using alcohol and drugs can affect how you function by leading to: 

  • poor concentration 
  • poor judgement – bad decisions, taking risks 
  • less productivity 
  • injuries 
  • absenteeism – time off work. 

There are no specific employment laws for workplace drug testing, but employers are responsible for keeping you and others in the workplace safe. Some businesses and high-risk work environments may need to focus more closely on safety, eg, where heavy machinery and equipment is being used or truck driving is involved. This means they might have developed a specific policy on workplace drug and alcohol testing.  

How often you might be tested depends on your workplace policies and your personal contract. It's likely to depend on your role and the risks associated with it.

Your employer doesn't have to give you any warning that testing is going to be done unless it's required by your contract or by workplace policies. 

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A company’s policy should clearly set out what happens next if employees or workers test positive for drugs or alcohol at work. 


If an employer has a drug and alcohol policy you might be asked to take a drug test if you apply for a job, as a condition of your application. You can refuse to take a drug test, but it will probably mean you won’t be considered for the role. 

Employment (on-the-job) testing 

Generally, an employer can only ask you to take a drug or alcohol test if it's: 

  • part of their health and safety policy 
  • a condition of your employment 
  • in your employment agreement. 

If you've signed an agreement to consent to drug and alcohol testing, your employer might choose to do it if: 

  • you work in a high-risk or safety sensitive environment 
  • your work directly affects the safety of other people 
  • you show signs of being affected by drugs or alcohol at work 
  • you have recently been involved in a workplace accident or near-miss. 

Even if you choose to use drugs or drink alcohol in your ‘own time’, the side effects of many drugs mean you could be a health and safety risk for yourself and others at work. Read more about the effects of alcohol.

You will have to provide a sample of urine (wee) to be tested. It usually takes about 10–15 minutes to complete a drug test, including paperwork and admin. The test itself takes about 5 minutes.  

You’ll need to bring photo ID, eg, a valid driver’s licence or passport. 

It’s recommended that you have at least 1 glass of water in the 2 hours leading up to the test. However, drinking too much might mean your urine sample is too dilute. If this is the case you might be asked to produce another sample. You should avoid going to the toilet for an hour before the test so you can provide enough urine to test. 

If your test is done onsite (eg, at a workplace) you should know the result about 5 minutes after giving the sample. If the test is done at a commercial testing facility (eg, Labtests), your results will be emailed to the address you provide at the time of collection, within 24 hours. If further testing is needed you will get the results after it's been done. 

The results of your drug test are very accurate. If an on-site test needs extra testing, it’s sent to an accredited laboratory for final, confirmed results.  

Sometimes medicines that you’re taking for legitimate reasons (eg, some vitamins, herbal remedies and fitness supplements) can cause a false positive result. An accredited lab can do further analysis to reveal exactly just what drug or substance is in your body. 

The only people who will know the results of your drug test are you, the hiring manager or HR (Human Resources) and the person who did the test. You’ll be provided with a copy of the completed test results. Your drug test results won’t be given to anyone else (eg, the police) without your permission. 

  • If the test is part of a pre-employment check, and you test positive, you’re unlikely to be hired in the role.  
  • If your test is at your workplace, your company’s policy should clearly set out what is acceptable, what isn’t and what will happen if you test positive.
  • There may be circumstances (eg, someone using medicinal cannabis) where an employer could be sympathetic and make changes to your role to enable you to keep working. For example, they might reassign you from driving or operating equipment to working in a lower-risk area.  

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

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