A random testing program should never feel random in the way it is run. Workers, supervisors and contractors need to understand what may happen, why it happens and how their privacy will be handled. Knowing how to organise random drug testing properly helps employers reduce safety risk while treating people consistently and respectfully.

For Queensland workplaces in mining, construction, transport, agriculture, civil works and industrial operations, the strongest programs are planned well before a tester arrives onsite. They have a clear policy, a defensible selection process, trained people managing the process and an agreed response pathway.

Start with the work health and safety risk

Random drug testing is a workplace control, not a stand-alone safety system. Consider the tasks being performed, the level of supervision, the presence of vehicles, mobile plant, heights, rail corridors, confined spaces, hazardous substances and fatigue-related risks. A worker whose role involves safety-critical decisions may create a different level of exposure than someone performing low-risk administrative work.

This risk picture helps determine whether random testing is appropriate, which groups are included and how often testing may occur. It also helps ensure the program matches the way the business actually operates, rather than being copied from another site with different hazards.

Testing frequency depends on the workplace, workforce size, client requirements and risk profile. A large project with rotating crews may need a different approach from a small local business with a stable team. The key is consistency: the program should be capable of being applied over time, not only after an incident or when concerns arise.

Put a clear policy in place before testing begins

A written drug and alcohol policy provides the operating rules for the program. It should be communicated to employees and made available to contractors before they attend site. Avoid vague wording such as “testing may occur at any time” without explaining the process.

Your policy should set out the purpose of testing, who it applies to, when testing can occur and the types of testing used. It should also explain the random selection method, privacy arrangements, how a non-negative screening result is managed, when confirmatory processes may be used and who is authorised to receive information.

The policy should sit alongside induction requirements, fitness-for-work expectations, incident procedures and relevant client or site rules. For contractor-heavy workplaces, make sure the same expectations are addressed in contractor onboarding and site access arrangements. A policy that only covers direct employees can leave a significant gap in higher-risk operations.

Workers should have a practical opportunity to ask questions before testing starts. Clear communication does not weaken a program. It reduces confusion, supports procedural fairness and makes it easier for supervisors to manage testing professionally when it occurs.

Use a genuinely random selection method

Random selection means each eligible worker has an equal or appropriately defined chance of being selected. It should not be based on appearance, rumours, personal relationships, shift preference or a supervisor’s judgement about who “looks suspicious”. Concerns about a person’s immediate fitness for work require a separate, documented process.

A reliable selection method is usually generated from a current list of eligible workers. Keep the selection process independent from line managers where practical, and keep a record showing how the selection was made. Depending on the workplace, the eligible pool may include employees, labour-hire personnel and contractors who are working under the same site rules.

To keep the process fair, establish the following controls:

• use an up-to-date worker list that reflects who is actually eligible to be tested;
• apply the same selection rules across comparable work groups and shifts;
• document the date, selection method and number of people selected;
• avoid giving advance notice that allows selected individuals to be identified or replaced.

Random does not necessarily mean every person must be selected from one large list. A remote project may need selections across day and night shift, or across separate work areas, so the program remains meaningful. If categories are used, document why they are used and apply them consistently.

Plan the day-of-testing process

Testing should be organised to minimise disruption without compromising confidentiality or collection requirements. Identify a suitable private area away from public traffic, lunch rooms and busy crib areas. Workers should not be tested where other people can overhear conversations or see personal information.

Before the testing day, confirm who will coordinate access, verify worker identification, notify selected people and manage any operational changes if a worker needs to be stood aside. Supervisors need to know their role, but they do not need access to more personal information than is necessary to keep work safe.

Have a practical contingency plan. Consider what happens if a selected worker is offsite, unavailable, called to an emergency task or due to leave before the test can be completed. Predetermine whether the person is replaced through the same random process, tested at the next available opportunity or managed under another documented rule. Ad hoc decisions can undermine confidence in the program.

For sites across regional Queensland, travel time and roster patterns can also affect scheduling. Workplace-based testing may be more practical when it is coordinated around shift starts, shutdown activity or planned contractor mobilisation, provided the selection itself remains protected.

Protect privacy and confidentiality

Drug testing information is sensitive. Treat it accordingly from collection through to storage and follow-up. Records should be kept securely, with access limited to authorised people who need the information for their role.

Workers should understand who receives results, what information a supervisor will be told and what will remain confidential. In many cases, a supervisor only needs to know whether a worker can continue performing their assigned duties, not the detail of the test process or any personal discussion.

Testing conversations should be conducted calmly and privately. Avoid public call-outs, speculation on the worksite or informal discussion between supervisors. Poor handling can damage trust quickly, even where the testing process itself is technically sound.

Know the difference between screening and a final outcome

A workplace screening result is not the same as a final finding. Your process needs to distinguish clearly between an initial non-negative result and any later confirmation process specified in your policy or site requirements.

This is where preparation matters. Decide in advance how a worker will be managed while the matter is being addressed, particularly if they perform safety-critical work. The response should be proportionate to the task, the available information and the rules that apply at the site. Do not leave a supervisor to improvise under pressure.

A suitable response plan may include removing a person from a particular task, arranging safe transport where required by site procedures, notifying the appropriate authorised contact and documenting the steps taken. It should be handled respectfully and without making assumptions or accusations.

Train supervisors to manage the process properly

Supervisors often carry the operational burden of random testing. They may need to release a worker from a task, arrange coverage, communicate with the testing provider and maintain a calm work area. Without guidance, they can accidentally disclose information or apply the process inconsistently.

Give supervisors a short, practical briefing on the policy, confidentiality expectations, escalation contacts and what they can and cannot say to workers. They should understand that random testing is not a disciplinary conversation and should not be used as an opportunity to investigate unrelated concerns.

Testing providers also need to work to a defined site process. Confirm collection arrangements, identification checks, documentation, result reporting channels and any applicable chain-of-custody requirements before the first testing day. Corrsafe can assist eligible workplaces with practical onsite drug and alcohol testing arrangements where available, helping align the testing activity with site operations.

Review the program without turning it into surveillance

A testing program should be reviewed periodically to check whether it is being run as intended. Look at broad operational measures such as the number of tests completed, missed selections, delays, contractor coverage, recurring administrative issues and whether workers understand the policy. Avoid using review data to identify or discuss individuals unnecessarily.

Review the program after major changes as well, such as a new project, a significant workforce increase, revised client requirements or changes to roster arrangements. Update policies and communications when the process changes, then make sure managers and workers receive the revised information.

The aim is not to catch people out. It is to maintain a workplace where everyone understands the fitness-for-work expectations that support safe decisions, safe plant operation and safe return home. When random testing is organised fairly, documented carefully and managed with respect, it becomes one practical part of making every move a safe one.