A recent Fair Work Commission ruling has sent a clear message to employers – outdated drug testing kits, inconsistent procedures, and poor investigations can lead to costly legal consequences.
The case of Maxwell Parks v WorkPac Pty Ltd highlights how failing to align workplace drug testing with current standards and policy can result in an unfair dismissal finding – even when a valid reason exists.
Mr. Parks was dismissed after returning not-negative drug test results at work, despite having conducted self-tests using Oral Fluid kits provided by the employer’s client, Batchfire, which indicated a negative result to THC. The Oral Fluid self-testing kits were aligned to the AS 4760:2006 standard cut-offs, while workplace testing was aligned to AS/NZS 4760:2019 cut-offs.
Oral Fluid testing units were made available in a private and confidential area for voluntary self-testing by coal mine workers and visitors prior to swiping onto the site access system. These Oral Fluid kits could be taken off-site and were intended to:
Under Batchfire’s policy, if a self-test returned a result at or above the prescribed limit, the individual was instructed not to commence work and to notify their supervisor. Sick leave provisions could be used, but repeat absences were managed under the site’s absenteeism procedures.
The policy referenced AS 4760:2006, which sets the THC detection threshold at 25ng/mL. However, the Oral Fluid kits used on-site were aligned with AS/NZS 4760:2019, which has a lower threshold of 15ng/mL for screening of THC.
This mismatch meant individuals with levels between 15ng/mL to 25ng/mL of THC were left with false confidence —self-testing at home in line with the workplace policy, but being tested at work to a stricter standard.
Mr. Parks Had:
Commissioner Simpson stated:
I have taken into account each of the matters that I am required to consider under section 387 of the Act. Whilst I have concluded that the Respondent had a valid reason for dismissal, the investigation conducted by the Respondent did not take into account all of the circumstances, and I have concluded the decision to terminate the Applicant was harsh given all of the circumstances, including the Applicant taking the proactive step of self testing before attending for work as he had been educated to do and returning negative tests, deficiencies in how the testing was undertaken, his unblemished work history, his personal circumstances, and the financial impact on him.
I am satisfied that the Applicant presenting to work to operate heavy machinery for the Assignment at the Mine two days in a row with THC in his system was a breach of WorkPac policy that was a form of misconduct that contributed to the Respondents decision to dismiss him, and on that basis I intend to reduce the amount of compensation awarded by 50%. That reduces the amount of compensation to $37,222.50.
This case is a powerful reminder that drug testing is not just about detection – it’s about fairness, accuracy, and consistency. Employers must:
Even if an older standard like AS 4760:2006 is referenced in the policy & procedure, relying on it may expose employers to legal and procedural risks – updating to AS/NZS 4760:2019 is highly recommended.
At Alcolizer Technology, we’re committed to helping employers avoid these pitfalls. Our solutions are:
If you’re unsure whether your current kits or policies are up to date, contact us for a compliance review. Let’s ensure your drug & alcohol workplace testing program protects both your people and your organisation.
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