A single data centre fire can disrupt millions of lives. With the UK's data centre capacity doubling by 2028, fire safety has never been more critical — or more complex.. The Data Centre Boom The UK data centre market is experiencing unprecedented growth: Current capacity : 1,200MW across 450+ facilities Projected capacity by 2028 : 2,400MW (doubling in 3 years) Investment : £12 billion in new data centre construction committed Critical dependency : 90% of UK financial transactions process through data centres Why Fire Safety Is Different Data centres present unique fire safety challenges that conventional approaches cannot address: 24/7 operation — evacuation means service disruption for millions High energy density — 5 15kW per rack, massive electrical fire load Battery storage — lithium ion UPS batteries with thermal runaway risk Water sensitivity — even small water leaks can cause catastrophic equipment damage Air handling — massive HVAC systems can distribute smoke throughout the facility Redundancy requirements — Tier III and IV facilities require concurrent maintainability Fire Risk Profile Common Causes of Data Centre Fires Electrical failures — 42% (loose connections, overloaded circuits, arc flash) Battery failures — 23% (thermal runaway in UPS systems) HVAC equipment — 15% (motor failures, bearing friction) Hot works during construction/maintenance — 12% External factors — 8% (wildfire, arson, adjacent property fires) High Profile Incidents OVHcloud Strasbourg (2021) — fire destroyed 2 of 4 data centres, 3.6 million websites offline Samsung Austin Semiconductor (2018) — power outage caused $50M in damage British Airways (2017) — data centre power failure (not fire) cost £150M Suppression System Design Gas Suppression Systems The primary fire suppression approach for data centres: Inert gas systems (IG 541, IG 55) — nitrogen/argon blend, safe for occupied spaces Chemical agent systems (FK 5 1 12, HFC 227ea) — fast acting, minimal residue Design standard : BS EN 15004 / ISO 14520 Key requirement : Total flooding with minimum 10 minute hold time Very Early Smoke Detection Apparatus (VESDA) Standard smoke detection is inadequate for data centres due to high airflow rates: Aspirating detection samples air continuously through a pipe network Detects smoke at concentrations 1,000x lower than point detectors Alert, Action, and Fire thresholds enable graduated response Essential for under floor and above ceiling detection in server halls Water Based Suppression Where gas suppression is impractical: Pre action sprinkler systems — double action (detection AND sprinkler head operation) Water mist systems — reduced water volume, less equipment damage Zoned approach — suppression limited to affected zone only Design Considerations Compartmentation Server halls separated from each other by 2 hour fire rated construction minimum UPS/battery rooms separated from server halls by 4 hour fire rated construction Transformer rooms in separate fire compartments with blast relief Cable routes protected with fire resistant coatings and cavity barriers Smoke Management HVAC shut down on fire alarm with automatic damper closure Smoke extract from affected compartment only Pressurisation of adjacent compartments to prevent smoke migration Fire rated ductwork where crossing compartment boundaries Business Continuity N+1 redundancy — no single fire event should disable the entire facility Concurrent maintainability — suppression systems maintainable without service disruption Automatic failover — services migrate to redundant systems within defined RTO Fire service pre plan — agreed response strategy that minimises water damage Emerging Risks AI and High Density Computing AI workloads are pushing power densities beyond traditional data centre design: GPU racks consuming 30 50kW (vs. 5 10kW for traditional servers) Liquid cooling systems introducing new fire and flooding risks Higher heat rejection requiring enhanced HVAC with associated fire risks Edge Data Centres Smaller, distributed data centres in urban locations present new challenges: Limited space for suppression agent storage Unmanned operation with remote monitoring only Adjacent to occupied buildings with different evacuation requirements Less stringent design standards than hyperscale facilities Magnus Opifex Data Centre Fire Engineering Fire strategy reports for new build and retrofit data centres Suppression system design review and specification VESDA system design and commissioning support CFD smoke modelling for server halls and cable routes Business continuity integration — fire safety aligned with uptime requirements Peer review — independent review of third party fire engineering designs Your data centre is critical infrastructure. Its fire safety should be engineered, not guessed. Contact us.