Technical manager dismissed for bypassing safety device: conduct dismissal upheld
A Technical Services Manager was fairly dismissed after bypassing an overheat stat on an air handling unit and swearing at a colleague. The tribunal found the employer's investigation and decision were within the range of reasonable responses.
1 min read · Last updated 19 May 2026
Case details
- #gross-misconduct
- #health-and-safety
- #bypassing-safety-device
- #obscene-language
- #summary-dismissal
Key facts
- The claimant was employed as a Technical Services Manager from 7 August 2017 until 14 April 2023.
- On 8 December 2022, the claimant bypassed the overheat stat on an Air Handling Unit (AHU) EV01.
- The bypass was discovered on 9 March 2023 after a carbon monoxide leak was reported.
- The claimant admitted to swearing at a colleague on 13 March 2023.
- The respondent conducted an investigation, disciplinary hearing, and appeal before dismissing the claimant.
- The tribunal found the dismissal was fair and within the range of reasonable responses.
Timeline
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Employment started
Claimant began employment as Technical Services Manager at Bluewater Shopping Centre.
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Bypass of overheat stat
Claimant bypassed the overheat stat on AHU EV01 and sent a photo to Lewis Coates.
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Discussion with Coates
Claimant asked Coates to permanently bypass the overheat stat; Coates refused.
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Fire damper repair
Fire damper specialist restored airflow to EV01, making it operative.
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Carbon monoxide detected
SGN detected carbon monoxide in EV01 ductwork and turned it off.
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Bypass discovered
Williams, Coates, and Fordham found the overheat stat still bypassed.
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Investigation meeting and suspension
Claimant walked out of investigation meeting and swore at Williams; then suspended.
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Disciplinary hearing
Hearing chaired by Michelle Fleming; claimant accompanied by colleague.
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Dismissal
Claimant summarily dismissed for gross misconduct.
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Appeal hearing
Appeal chaired by Matthew Hadley; dismissal upheld.
The legal issue
The tribunal had to decide whether the employer had a genuine belief on reasonable grounds after a reasonable investigation that the claimant committed misconduct, and whether dismissal was a fair sanction.
The outcome
The tribunal dismissed the claimant's unfair dismissal claim, finding the dismissal was fair.
The key reasons were:
- The employer genuinely believed the claimant had bypassed a safety device and used obscene language.
- The employer carried out a reasonable investigation, including a disciplinary hearing and appeal.
- Dismissal was within the range of reasonable responses for a manager with health and safety responsibilities.
No compensation was awarded as the claim failed.
Lessons & takeaways
- Employers should conduct a thorough investigation before dismissing for misconduct, including giving the employee a chance to respond.
- Health and safety breaches by managers are likely to be treated seriously by tribunals, especially where there is a risk to others.
- Swearing at colleagues can be gross misconduct if it undermines working relationships or authority.
- Employees should cooperate with investigations – walking out of a meeting can harm their case.
When bypassing a safety device leads to dismissal
This case shows how seriously tribunals treat health and safety breaches, particularly when committed by a manager. The claimant, a Technical Services Manager with five years' service, bypassed the overheat stat on an Air Handling Unit (AHU) in December 2022. The bypass was discovered three months later after a carbon monoxide leak was reported. The claimant also admitted swearing at a colleague during the investigation.
What the employer did right
The employer carried out a full investigation, held a disciplinary hearing, and considered an appeal. The tribunal found that the employer genuinely believed the claimant had committed gross misconduct, had reasonable grounds for that belief, and had conducted a reasonable investigation. The decision to dismiss was within the range of reasonable responses, given the claimant's senior role and the serious nature of the misconduct.
What the claimant could have done differently
The claimant represented himself and argued that the bypass was necessary to keep the shopping centre operational. However, the tribunal noted that the claimant had asked a colleague to permanently bypass the device, which the colleague refused. The claimant also walked out of the investigation meeting and swore at a colleague, which further damaged his position. Cooperating with the investigation and showing remorse might have led to a different outcome.
Why this matters for similar claims
This case reinforces that employers can fairly dismiss for gross misconduct if they follow a fair process and have reasonable grounds for their belief. Employees in senior roles with health and safety responsibilities should be particularly careful not to bypass safety devices, even if they believe it is necessary for operational reasons. The tribunal will not substitute its own view for that of the employer, as long as the employer's decision was within the range of reasonable responses.
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