One Authorised Person and Three Weeks of Leave
A 6.5 MW data centre runs two 12-hour shifts with eight technicians, a supervisor, and a contract requiring at least two qualified persons on site at all times. Of the eight technicians, only one holds the high-voltage switching authorisation for the 11 kV intake, and he starts three weeks of pre-booked leave next Monday. During his absence a generator load test and a utility breaker service are scheduled, both requiring switching. Overtime reached 38% of total hours last quarter, and at 05:20 last week a night technician missed a critical chilled-water alarm for 22 minutes; he had worked four consecutive nights and told his supervisor he had not slept properly. The training matrix shows three technicians have never been assessed on the current BMS release and two are overdue for first-aid refresher. The client has just requested evidence of competent cover for the leave period.
1. How do you cover the leave period without breaching the contract or the switching rules, and what do you tell the client?
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Separate the two obligations. The contract is about qualified persons being on site; the switching authorisation is about who may legally and safely operate the 11 kV system. Borrowing an unqualified body to satisfy a headcount does not solve the second problem, and using an unauthorised person to switch is a safety and legal exposure that no staffing rota justifies.
Options, in order of preference.
- Reschedule the elective work. The utility breaker service and the generator load test are planned, not forced. Deferring them into the week after his return is the lowest-risk option, provided the generator test interval and the service window can absorb a three-week slip - check the manufacturer's interval and any contractual testing obligation before committing.
- Import a competent person. Engage a contracted authorised person with current, verified authorisation for the same voltage and equipment class, inducted on the site's switching schedule, single-line diagram and permit system. Verify the authorisation document, not a CV.
- Reduce the scope of the load test to an automatic transfer test that requires no HV switching, and record explicitly that it is a partial test so nobody later claims full coverage.
What not to do. Do not appoint the supervisor as acting authorised person by email. Authorisation follows a competence assessment and a formal appointment against the site's electrical safety rules.
Tell the client the cover plan, the named and verified competent person, the revised dates for the deferred work, and the residual risk while elective maintenance is deferred. Silence is what turns a staffing issue into a contractual dispute.
2. Design the corrective plan for the competence gap and the fatigue problem, with measures you would report monthly.
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Competence gap. A single authorised person is a single point of failure by design. Build a second and third: a documented authorised-person programme with prerequisites (experience record, HV safety rules training, witnessed switching operations, assessment by an external or independent assessor), a target of two authorised persons per shift pattern within twelve months, and an interim rule that no HV work proceeds without an authorised person plus a second competent person present. Close the BMS assessment gap with a hands-on assessment against the live release, including alarm response scenarios, not a slide deck. Keep first-aid refreshers on a tracked calendar with a 60-day advance trigger.
Fatigue. 38% overtime across a 12-hour shift pattern is a direct safety risk, and the 22-minute missed alarm at 05:20 on a fourth consecutive night is the evidence. Controls: a maximum consecutive-night limit (commonly two or three, agreed with the workforce), a hard rule that overtime cannot be added to a night shift, a fatigue-reporting route that does not penalise the reporter, and a review of whether the 12-hour pattern with eight people is structurally under-resourced - eight technicians for 24/7 coverage is thin once leave, sickness and training are deducted.
Monthly measures to report. Number of authorised persons available per shift; percentage of shift hours covered by two qualified persons (target 100%); overtime as a percentage of hours (target below 15%); consecutive-night breaches (target zero); overdue competence assessments (target zero); alarm response times, particularly at night; and near-miss reports per month, with the trend valued as an early-warning signal rather than a failure count. Report leading indicators alongside the missed-alarm metric, otherwise the only thing you learn about is the incident that already happened.