In relation to fire safety in buildings, a raised flooring system at a height of more than 600mm from the original floor should have adequate fire resisting rating (FRR) in compliance with the Code of Practice for Fire Safety in Buildings published by the Buildings Department¹ (BD).

In recognition of the operational need of using some raised flooring systems with a height of more than 600mm as air plenum for cooling of special equipment, servers, etc. in a data centre, the BD has adopted a pragmatic approach to approve such raised flooring systems in server room, computer data hall or other similar accommodation in a data centre to be without FRR, subject to justifications on the operational need of an air plenum of more than 600mm in height and the provision of fire service installations in accordance with the Code of Practice for Minimum Fire Service Installations and Equipment and relevant Circular Letters issued by the Director of Fire Services.

In addition, structural plans of the proposed raised flooring system should be submitted to the BD to demonstrate its capability to safely sustain the dead loads and imposed loads arising from the intended use or purpose during the service life of the raised floor, such as the installation of computer equipment, machinery and servers.

1. Pursuant to the powers under the Buildings Ordinance (BO), the BD is responsible for the enforcement of the safety and health standards for the planning, design and construction of buildings and associated works on private land. Thus, the BO has also set the building design and construction standards on structural and fire safety as well as health issues.