Data centres and telecommunications facilities are providing mission critical services for their clients. Hence, for the providers business continuity is paramount to deliver promised high levels of service. Fire, along with unintended operation of Emergency Power-Off (EPO), remains the single Point-of-Failure even for a tier IV facility, assuming a site outage occurs no more than once every five years. Any operation interruption due to a fire event – or even a false fire alarm – could lead to an unacceptable extended downtime to customers. Datacom facilities operation reliability is subject to the rigorousness of – among others – fire resilience, whereof Early Warning Fire Detection is a central element. When designing an advanced fire safety system to protect mission critical facilities, general Deem-to-Satisfy (DtS) prescriptive building and fire codes for building protection and life safety are essential. However, most important is applying Performance-based Design (PBD) methodologies to safeguard business continuity.