How to hire a data centre commissioning engineer

A data centre (data center in US usage) commissioning engineer proves that power, cooling and controls work as designed before live IT load arrives. Hiring one well means fixing the scope first and starting the search from the commissioning schedule, not the go-live date. Then test candidates for evidence of integrated testing on comparable plant.

What does a data centre commissioning engineer do?

Commissioning verifies that equipment and systems operate as the engineer of record designed them, and sets a performance baseline for the life of the facility. It also lets the operations team learn the systems without risking critical IT load (Uptime Institute Journal, May 2015). The commissioning engineer is the person who plans, witnesses and records that testing for one or more disciplines.

Uptime Institute groups the work into five levels and runs Levels 1–3 during construction, covering factory witness tests, post-installation checks, and start-up and functional checks (Uptime Institute Journal, May 2015). While those run, the commissioning authority and the operations team write the scripts for Levels 4–5.

Level 4 includes load bank tests of the engine-generator sets, UPS and UPS batteries at design and rated capacities. Continuous load bank runs of up to 24 hours are described as best practice (Uptime Institute Journal, May 2015). Level 5 is integrated systems testing (IST): the whole facility is tested together, on utility power and on generator power, with fire detection and suppression live rather than bypassed.

Definitions of each level vary between organisations, and Uptime Institute notes that an activity may sit in a different level on some projects (Uptime Institute Journal, May 2015). Read the project's commissioning specification before writing the job description, so the brief uses the same level definitions as the site.

Which commissioning role does the project need?

Three roles are often confused in briefs. The commissioning authority (CxA) owns the commissioning process for the owner. The commissioning manager runs the plan, schedule and scripts across disciplines. Commissioning engineers prepare and run tests in one discipline, usually electrical, mechanical or controls.

Uptime Institute guidance says the CxA should ideally be an independent third party contracted directly to the owner, not a contractor or designer employee (Uptime Institute Journal, May 2015). The US General Services Administration describes independent third-party commissioning as industry best practice, because it removes the conflict of contractors verifying their own work (GSA, Sep 2020).

Contractors and OEMs still need their own commissioning engineers to run equipment, coordinate vendors and fix defects. A developer hiring for the owner side and a contractor hiring for the delivery side are therefore running different searches, with different candidate pools and different interview tests.

When should commissioning hiring start?

Earlier than most hiring plans assume. Uptime Institute guidance starts commissioning immediately after project approval, with selection of the CxA. Selected at pre-design, the CxA can help shape the owner's project requirements (OPR), the basis of design (BOD), the budget and the schedule (Uptime Institute Journal, May 2015).

The GSA guide makes the same point: a commissioning provider brought in at project initiation reviews the OPR and BOD first. Changes made in design also cost less than changes made after installation begins (GSA, Sep 2020). For hiring, that means the owner-side commissioning lead is a design-stage hire, not a construction-stage one.

Discipline engineers are needed before the first factory witness tests at Level 1, and the team is at its widest during Levels 4–5. Uptime Institute guidance positions commissioning team members and contractors across the facility to monitor all systems during Level 5. A rigorous Level 5 schedule could take up to 20 working days or longer (Uptime Institute Journal, May 2015).

Work back from those dates. A late hire who joins during Level 4 inherits scripts written by someone else and has little time to learn the plant before integrated testing starts.

Why are commissioning engineers hard to hire?

The shortage is broad and getting worse. More than half (53%) of operators report difficulty finding qualified candidates for vacant roles, a statistically significant rise from 46% in 2025 (Uptime Institute, Jul 2026).

Electrical skills are where the gap has grown fastest. Electrical roles are cited by 38% of operators reporting skills gaps, level with junior and mid-level operations, and up 13 percentage points since 2023 (Uptime Institute, Jul 2026). Uptime links this to gigawatts of new electrical infrastructure being built, commissioned and operated.

Retention is the other half of the problem. 28% of operators say they have had staff hired away by competitors (Uptime Institute, Jul 2026). Uptime adds that many operators have responded by spending more on pay, both to keep staff and to recruit trained people from rivals. Expect strong commissioning candidates to hold competing offers, and plan the interview process to close quickly.

Where do commissioning engineers come from?

Most experienced candidates come from three places: commissioning firms, M&E contractors and equipment OEMs. Each brings a different strength. Commissioning firms bring scripting and witnessing, contractors bring installation knowledge, and OEM engineers know their own switchgear, UPS or chillers in depth.

Uptime Institute advises operators to recruit and train staff from diverse sources, including universities, trade schools and industries with overlapping skill sets (Uptime Institute, Jul 2026). Job adverts point the same way. One Irish data centre advert names pharmaceutical and large-scale industrial projects as relevant experience, and lists Level 5 IST experience as highly desirable (indicative, Darwin Recruitment, 2026).

An adjacent-industry hire usually needs coaching on Level 5 testing on a live critical facility. Pair that hire with a lead who has run integrated testing before, and test the candidate's transferable evidence with the scorecard below rather than the sector name on the CV.

What should a commissioning engineer scorecard test?

The scorecard below combines commissioning guidance from Uptime Institute and the GSA with the electrical safety appointment model in NHS England's HTM 06-02. Score each competency from evidence the candidate can describe in detail, not from job titles.

Competency	Strong evidence	Interview probe	Basis
Electrical testing (MV/LV switchgear, UPS, generators)	Has witnessed factory tests and led site load bank tests at design and rated capacity	"Talk through a UPS load bank test you ran: load steps, duration, what failed and what changed."	Uptime Institute Journal
Level 5 integrated systems testing	Has written or run IST scripts, including tests on utility and generator power	"Which integrated test had to be repeated, and how was the retest scoped?"	Uptime Institute Journal
Controls literacy (BMS and EPMS)	Has commissioned control graphics, alarms and trends before integrated testing	"How do you check that alarms and trends are ready before IST starts?"	Uptime Institute Journal
Electrical safety authorisation (AP/SAP)	Holds a written appointment for defined systems under a site's electrical safety rules	"Who appointed you, for which systems, and how did you control safety documents?"	NHS England HTM 06-02
Documentation (OPR, BOD, scripts, systems manual)	Can share a redacted commissioning plan, method statement or script they wrote	"Show a script you wrote and explain one acceptance criterion in it."	Uptime Institute Journal
Independence and owner perspective	Has worked for the owner or a third party and has failed a contractor's test on evidence	"Describe a test you refused to sign off. What happened next?"	GSA Commissioning Guide
Handover to operations	Has run operator training and closed out punch-list items after integrated testing	"What did the operations team receive from you at handover?"	GSA Commissioning Guide

Under HTM 06-02, an Authorised Person is appointed in writing and is responsible for work on, or testing of, defined electrical equipment (NHS England, HTM 06-02). Ask for the scope of any AP or SAP appointment, because it is tied to named systems and sites rather than carried from job to job.

Weight the rows to the role. An owner-side commissioning manager should score highest on documentation and independence. An electrical commissioning engineer for a contractor should score highest on electrical testing and safety authorisation.

How should the search be run?

A commissioning search works best as a short, ordered sequence tied to the commissioning schedule:

1. Define the role: owner-side CxA or manager, contractor commissioning engineer, or a discipline specialist in electrical, mechanical or controls.
2. Set the start date from the commissioning plan, working back from the first factory witness test rather than from go-live.
3. Write the brief around evidence: the levels the candidate has run, the systems tested and the scale of the sites.
4. Source from commissioning firms, contractors, OEMs and adjacent industries at the same time, not one after another.
5. Interview with the scorecard, a technical walk-through of a real test and a redacted document sample.
6. Take references on specific tests the candidate claims to have led, then close quickly, since competitors are hiring from the same pool.

What does a commissioning engineer cost?

Public pay data for data-centre-specific commissioning roles is thin, so treat the figures below as indicative only. In the UK, permanent commissioning engineer adverts quoted £42,500–£69,000 a year between the 10th and 90th percentiles in the six months to October 2026 (indicative, ITJobsWatch, 2026).

UK commissioning manager adverts quoted £70,000–£101,750 a year over the same period, from a small sample of adverts (indicative, ITJobsWatch, 2026). ITJobsWatch tracks adverts across sectors, so these ranges are not specific to data centres.

In the US, one aggregator reports commissioning engineer base pay of $69,000–$118,000 between the 10th and 90th percentiles across all sectors (indicative, Payscale, 2026). Data centre roles with travel, accommodation or rotation allowances can sit outside these ranges, so benchmark against live adverts for the site's market before making an offer.

Workfully is an AI-native recruiting company. AI agents match each role to recruiters with proven data centre placements in that market. Several recruiters work each role in parallel from day one, with every stage tracked in one place (Workfully for data centres).