What happened
On 24 November 2021, shortly after 10am, Sean O’Connor, 34, was electrocuted at Columbus House, 7 Westferry Circus, Canary Wharf, while changing a heat-pump flow switch in a plant room. He was a Mitsubishi employee. The medical cause of death was electrocution.
He was a lone worker on the job. Under the risk assessment and method statement, he should have asked a Canary Wharf Management Limited colleague to check on him during the day. He did not. A CWML employee thought of doing so, was busy, and did not go.
The inquest jury returned a conclusion of death by accident on 1 May 2024.
The outcome
No prosecution was brought. On 8 May 2024 the Senior Coroner for Inner North London, Mary Hassell, issued a Regulation 28 Prevention of Future Deaths report, reference 2024-0257, to the chief executive of Canary Wharf Management Limited.
The coroner wrote that a check was likely to have been too late to change the outcome for Mr O’Connor, but that it might be different for another lone worker. A CWML director agreed at the inquest that it would be straightforward to add a brief question to the routine site induction, asking whether checks are needed during the day, so that an operative who forgets to ask is reminded. CWML had until 15 July 2024 to respond. The response is not published in the sources read.
What went wrong
The control had no owner. The method statement put the trigger on the man doing the job: he had to ask. The check put the trigger on a colleague: somebody had to remember and be free. Neither side had a time, a name, or a consequence for silence.
A plant room is where a lone worker is hardest to see. The person who thought of him had their own work at the other end of a large site, and being busy was enough to stop the check. That is not a failure of care. It is what happens when a control depends on goodwill at ten in the morning.
The host employer’s induction never asked the question. The coroner’s point is that it could have, and that the question costs nothing.
What it teaches
A check-in with no named time, named person and missed-check escalation is not a control. Write it before the job starts: who calls whom, at what time, and what happens when nobody answers.
Where a lone worker is on someone else’s site, the host’s induction is the natural place to ask whether checks are needed. That question turns an informal favour into a system.
The coroner was careful: the check might not have saved this man. The case is worth teaching anyway, because the next lone worker may be found sooner.
Questions for the room
- Before your next lone task, what is the agreed check-in time, with whom, and what happens if you miss it?
- If you are the host, what question do you ask every contractor at induction, and is it on the form?
- What would have to be true for “I was busy” to be impossible as a reason?
Evidence and limits
Confidence: confirmed. Two documents on the Judiciary website were read in full: the Prevention of Future Deaths report page and its PDF, which carry the same content. The page reports what the coroner records and quotes her where it attributes.
The sources do not include Mitsubishi’s risk assessment, the HSE’s position, or CWML’s response, so the page makes no claim about any of them. Nothing in the sources says who found him or when.
If your staff work alone on other people’s sites, our lone working training covers check-in design and host-employer induction.
Sources
- Courts and Tribunals Judiciary, 2024 · https://www.judiciary.uk/prevention-of-future-death-reports/sean-oconnor-prevention-of-future-deaths-report/
- Courts and Tribunals Judiciary, 2024 (PDF) · https://www.judiciary.uk/wp-content/uploads/2024/05/Sean-OConnor-Prevention-of-future-deaths-report-2024-0257_Published.pdf
Reviewed 20 October 2026.