One of the most persistent challenges in workplace drug and alcohol testing is ensuring that all employees are tested equitably, regardless of when they work. Organisations that run day, night, and rotating shifts often find that their testing programs disproportionately cover day-shift workers — simply because testing is easier to arrange during business hours when collectors, HR personnel, and management are available.

This inequity is more than an administrative inconvenience. It is a compliance risk, a fairness issue, and, in some cases, a safety gap. If night-shift workers know they are unlikely to be tested, the deterrent effect of the program is significantly diminished. This article addresses the practical challenges of testing across all shifts and provides strategies for getting it right.

Ensuring All Shifts Are in the Selection Pool

The foundation of equitable testing is ensuring that every eligible employee is included in the random selection pool, regardless of their shift pattern. This sounds straightforward, but in practice, several common issues can lead to gaps:

• Roster data accuracy — if your selection pool is based on roster data, it must be current. Employees who have moved between shifts, are on leave, or have changed roles must be reflected accurately in the system.
• Shift-based sub-pools — some organisations create separate selection pools for each shift and run selections independently. This ensures that each shift is represented, but it requires careful management to maintain statistical validity and genuine randomness within each pool.
• Contractor and labour hire inclusion — shift workers supplied by labour hire agencies or working as contractors must be included if your policy covers them. Their shift schedules may not be captured in your primary rostering system, so a separate process may be needed.

Your testing management software should make it straightforward to maintain an accurate, up-to-date pool that includes all shifts. If you are relying on manual spreadsheets, the risk of gaps increases significantly.

Logistics of Night Shift Testing

Night shift testing presents unique logistical challenges that require specific planning:

• Collector availability — not all testing providers offer after-hours collection services. When selecting a provider, confirm their ability to attend your site during night-shift hours. If using in-house testers, ensure they are trained, available, and rostered to conduct tests during night shifts.
• Supervision and authorisation — the person authorised to initiate testing must be available during the shift. If this is typically a day-shift HR manager, a delegate must be appointed for night-shift events. The delegate must have the authority and training to manage the process.
• Testing environment — ensure that an appropriate testing location is available during night shifts. The same requirements for privacy, lighting, and hygiene that apply during the day must be met at night.
• Communication chain — if a positive screening result occurs during a night shift, the process for notifying HR, arranging stand-down, and managing the employee must be defined in advance. Waiting until the next business day is not acceptable if safety is at stake.

Equity Across Rosters

Equity in testing means that over time, each shift has a proportional representation in testing events. If seventy per cent of your tests are conducted on day shift but day-shift workers represent only forty per cent of your workforce, the program has an equity problem.

To achieve equity:

• Track testing by shift — maintain records of which shift each test was conducted on and review this data regularly to identify any imbalance.
• Set shift-specific targets — if your policy specifies an annual testing rate (e.g., fifty per cent of the workforce), break this down by shift to ensure each shift is covered proportionally.
• Rotate testing events — plan your testing schedule so that events are distributed across all shifts throughout the year. If you conduct monthly testing events, ensure that some of those events fall on night shifts and weekend shifts.
• Report to management — include shift distribution data in your regular compliance reports. This demonstrates to management (and to auditors or regulators) that the program is being applied equitably.

Practical Scheduling Strategies

Scheduling testing across multiple shifts requires a structured approach. The following strategies can help:

• Annual testing calendar — at the start of each year, create a testing calendar that maps testing events across all shifts for the full twelve months. This ensures coverage is planned rather than ad hoc.
• Shift changeover testing — conducting tests during shift changeovers captures workers from both the outgoing and incoming shifts. This is operationally efficient and ensures both shifts are represented.
• Rotating collector schedule — if using in-house testers, create a roster that rotates collectors across different shifts. This normalises testing on all shifts and reduces the perception that any particular shift is being targeted.
• Remote site coordination — for FIFO (fly-in, fly-out) or remote operations with defined swing rosters, coordinate testing with swing changeovers to capture both incoming and outgoing crews.

Collector Availability and Training

Having trained collectors available across all shifts is a prerequisite for equitable testing. Options include:

• In-house collectors — training employees on each shift as collectors ensures coverage at all hours. This is particularly important for organisations that operate 24/7 and cannot rely on external providers for after-hours testing.
• External providers with after-hours capability — if outsourcing collection, negotiate service-level agreements that include after-hours and weekend availability. Confirm that the provider’s collectors hold current training and certification.
• On-call arrangements — for organisations that do not test frequently enough to justify rostered after-hours collectors, an on-call arrangement with an external provider can ensure that testing can be arranged at short notice across all shifts.

Fatigue Considerations

Testing during night shifts intersects with fatigue management in important ways:

• Timing within the shift — avoid testing at the end of a long night shift when fatigue-related symptoms may be mistaken for impairment indicators. Testing at the start of the shift or during a break is generally more appropriate.
• Distinguishing fatigue from impairment — supervisors should be trained to recognise that some indicators of impairment (drowsiness, slow reactions, poor coordination) can also be symptoms of fatigue. This is particularly relevant for reasonable suspicion assessments during night shifts.
• Rest period obligations — ensure that the time taken for testing does not reduce the employee’s mandatory rest period between shifts. This is a regulatory requirement in some industries and a good practice in all.

Getting Full Coverage

An effective testing program covers the entire workforce, not just the workers who happen to be on site during business hours. By planning ahead, tracking coverage data, and investing in the logistics of after-hours testing, you can ensure your program is equitable, defensible, and effective across every shift.

If you need a platform that makes it simple to manage selections, testing, and reporting across all shifts and rosters — start your free trial with FairTest and ensure no shift is left behind.