Workplace drug testing can be a powerful tool for maintaining safety, productivity, and a healthy culture — especially in high-risk industries like transport, construction, or mining. But timing matters just as much as the testing itself.
Whether you're reviewing your drug and alcohol policy or implementing one for the first time, understanding when you can — and can’t — drug test employees is crucial for legal compliance and maintaining trust within your team.
Let’s break it down.
✅ When you should drug test your employees
Workplace drug testing is most effective when done for the right reasons and at the right time. Here are the most common (and legally sound) scenarios:
1. Pre-employment testing
Testing candidates before hiring is common in safety-sensitive roles. It helps ensure that employees entering the workforce are fit for duty — particularly important in sectors like:
- Transport and logistics
- Construction and infrastructure
- Mining and resources
- Aviation or maritime operations
Make sure this is clearly communicated to candidates as part of your hiring process.
2. Random testing
Random drug testing is a preventative strategy used to maintain a safe, drug-free workplace. It must:
- Be conducted fairly (random selection with no bias)
- Be part of a written drug and alcohol policy
- Focus on roles where impairment poses a risk
🚫 Blanket testing — where all employees are tested regardless of role — is generally not advised unless all roles carry high safety risks.
3. Post-incident testing
If an accident or near-miss occurs, post-incident testing can determine whether drugs or alcohol played a role. This:
- Supports your WHS obligations
- Helps guide return-to-work decisions
- Can assist in insurance or legal investigations
4. Reasonable suspicion
If a supervisor notices signs of impairment (e.g. slurred speech, unsteady movement, smell of alcohol), this can warrant a test — but only if your policy allows for it and the suspicion is clearly documented.
Make sure managers are trained in recognising these signs and following procedure.
5. Return-to-work or follow-up testing
After rehabilitation or time off related to substance use, ongoing testing may be agreed upon as part of a recovery plan. This ensures that employees remain safe and supported as they return to work.
When you can’t or shouldn’t drug test your employees
While drug testing is legal in Australia, it must be fair, reasonable, and proportionate to the risks involved. Here’s when it can become a legal grey area — or outright breach:
❌ Blanket testing in low-risk roles
You should not test employees indiscriminately if they’re in non-safety-sensitive roles (like admin, finance, or marketing). Testing must relate to the nature of the work.
❌ Without a policy or informed consent
Testing is only lawful if employees:
- Are aware of the policy
- Understand how and when testing may occur
- Have provided consent (ideally in writing)
Without these, you may be in breach of employee rights or privacy laws.
For more information, refer to Safe Work Australia’s guide on alcohol and other drugs.
Best practices for compliance and fairness
To avoid legal issues and build trust with your team, make sure you:
- ✅ Develop a clear Drug and Alcohol Policy
- ✅ Use certified testing methods (e.g. AS/NZS 4308 or AS/NZS 4760 drug test kits)
- ✅ Train managers on recognising signs of impairment
- ✅ Respect employee privacy and rights
- ✅ Provide access to Employee Assistance Programs (EAPs) or support services
Explore our Workplace Drug Testing Kits to stay compliant with Australian Standards.
Testing is about safety, not punishment
A fair, well-timed drug testing program protects your people — and your business. But it only works when implemented transparently and legally.
If you're unsure when or how to test, start by reviewing your policy. Need help? Andatech can assist with drug testing kits, guidance, and policy support.
Contact us to learn how we can help you build a safer, more compliant workplace.
