When a workplace incident occurs — whether it's an injury, near miss, or property damage — safety teams need to act fast. One crucial step in any incident response plan is post-incident drug and alcohol testing.
This helps determine whether substance use was a contributing factor and ensures your team stays compliant, protected, and accountable.
When should post-incident testing take place?
Post-incident drug and alcohol testing should occur immediately after any workplace incident, such as:
- A workplace injury or fatality
- A near miss involving equipment or vehicles
- Significant property or equipment damage
- Unsafe behaviour that puts others at risk
The sooner testing is carried out, the more reliable and legally defensible the results will be. Delays can cause substances to metabolise or leave the system — particularly alcohol — which could compromise the investigation.
DISCOVER MORE: Random drug testing at the workplace
Why post-incident testing matters
Testing after a workplace incident helps to:
- Ensure safety – Confirms whether workers involved were fit for duty at the time.
- Protect your business – Demonstrates your duty of care and reduces legal exposure.
- Support incident investigations – Identifies contributing factors and helps prevent future occurrences.
- Reinforce your safety culture – Sends a clear message that impairment on the job won't be tolerated.
A 2020 study cited an older study which found that 16% of fatal workplace injuries in Australia involved workers with a Blood Alcohol Concentration (BAC) above zero.
Best practices for post-incident drug and alcohol testing
✅ Have a clear workplace policy
Your drug and alcohol testing policy should outline when and how post-incident testing will be conducted. This keeps the process fair and transparent.
✅ Test as soon as possible
Don’t wait. The longer you delay, the less accurate the results — especially for alcohol or short-acting substances.
✅ Use certified testing equipment
Only use AS/NZS-compliant breathalysers and drug test kits to ensure your results are accurate and legally defensible.
✅ Maintain confidentiality
Testing must be handled discreetly, with respect for privacy and documentation handled securely.
✅ Document everything
Record the reason for testing, the equipment used, test times, results, and any follow-up action. This protects both the worker and employer in any future disputes.
Common mistakes to avoid
❌ Delaying the test
Even a few hours can affect result accuracy — act fast.
❌ Testing without policy backing
Ensure testing is supported by a clear, communicated policy to avoid legal risks.
❌ Using non-compliant tools
Avoid cheap or uncertified equipment — it’s not worth the risk in a legal situation.
❌ Skipping documentation
If it’s not written down, it didn’t happen. Keep records for internal and legal purposes.
Ensure a drug-free workplace today
Post-incident drug and alcohol testing is a key part of any workplace safety strategy — but only when done correctly. By testing quickly, using compliant tools, and documenting the process thoroughly, you can protect your workforce, support fair investigations, and reduce legal risks.
Pair post-incident drug testing with random drug and alcohol testing to deter the use of substances during working hours.
Recommended equipment for post-incident testing
With trusted tools, you're equipped to take action with confidence — ensuring every result is accurate, compliant, and defensible.
DrugSense DS08+ Oral Drug Test Kit
A fast and accurate saliva drug test that detects recent drug use, ideal for post-incident scenarios where timeliness is critical. Verified for compliance with AS 4760.
Andatech Prodigy S Breathalyser
A professional-grade breathalyser with police-level accuracy, certified to AS 3547. Perfect for on-site alcohol testing after an incident, with results you can rely on. Details of test subject can be stored on device and even printed via the Bluetooth printer as part of the print pack version of the breathalyser.
In high-risk industries, post-employment drug testing is more than just a box to tick — it's a key part of keeping your workforce safe.
FURTHER READING: Pre-employment drug and alcohol testing in Australia
