C120-H007-05EN 17
2.3 Computer Room Structure
zSecurity and disaster prevention considerations
(1) Base floor strength
The base floor on which the server system is to be set up must have enough strength to
support a raised floor and facilities and equipment, as well as the server system itself.
A floor top view with an equipment layout superimposed with equipment weights for
each lockers must be presented to the building designer or the building constructor as
a means of determining whether the server system can be installed on the floor in
question.
For base floor strength, see Section 2.2.1, "Building structures."
(2) Dustproof finishing
If the surface of the base floor is left unfinished, equipment may be adversely affected
by calcium carbonate scattered as dust from the concrete surface. The concrete
surface must be finished with a dustproof coating to prevent the buildup of dust.
(3) Free-access floor construction
Server rooms covering an area of about 30 m2 (320 ft2 ) or more should have a raised
floor structure as far as circumstances allow. A raised floor structure with a free-
access floor that allows floor plate removal is recommended to facilitate equipment
installation and relocation, cabling, and underfloor ventilation. Requirements for the
raised floor height of a free-access floor and the floor panel strength are described in
Section 2.3.2, "Free-access flooring."
(4) Ceiling height
The ceiling of the computer room must be high enough to allow for the circulation of
cold air up from under the free-access floor to the heated equipment which it cools
down before flowing unrestrained within the room back to the air conditioner. The
ceiling height is measured from the surface of the free-access floor (raised floor) to
the bottom layer of the double ceiling. The values specified in Table 2.1 are required
depending on the equipment height.
Table 2.1 Ceiling heights
Equipment height Ceiling height
Up to 1.8 m (5.9 ft ) 2.3 m (7.5 ft ) or higher
Above 1.8 m (5.9 ft) but not exceeding 2.0 m (6.6 ft) 2.5 m (8.2 ft ) or higher