HP 3PAR StoreServ 10000 Storage Physical Planning Manual

Additional Flooring Recommendations
Consider the following recommendations for raised floor installations:
• The flooring should be high enough to allow under the floor routing of cables and specified
airflow to system air intakes. The recommended minimum floor clearance is 30.5 cm (12 in).
An additional 7.6 cm (3 in) should be allowed for cables and connectors. A floor clearance
of 46 cm (18 in) is recommended for new construction.
Additional panel support may be required to restore the structural integrity of a raised floor
panel that has been cut for air opening, cable entry, and so on. Raised floors without stringers
may also require lateral support to prevent floor tile movement.
The finished floor-to-ceiling height should be a minimum of 2.44 meters (8 feet).
• The subfloor must have adequate drainage to prevent flooding and trapping of water beneath
the raised floor. Cement should be sealed to prevent the formation of particulates.
• To avoid an electrical hazard when using a metallic floor, no metal or conductive material
should be exposed to the walking surface.
• Sharp edges must be eliminated on all floor cutouts where cables pass. For wood or similar
core material, all cut edges must be covered with metal or plastic clips or grommets so that
none of the core is exposed (see NFPA 75 requirements).
• Asphalt tiles are not recommended because they produce dust that may cause equipment
malfunction.
• Carpeting is not recommended because it produces and holds dust, and can contribute to the
buildup of electrostatic charges on people and equipment.
• Most raised floors are composed of 60 cm (International/Metric) or 24 in. (Domestic/American
Standard) square floor tiles. The maximum panel size should not exceed 60 by 90 cm
(International/Metric) or 24 by 36 in. (Domestic/American Standard). The panels should have
a flame spread rating of 15 or better when tested according to the American Society for
Testing and Materials (ASTM) Standard E 84.
• The floor covering can contribute to a buildup of high static electrical charge. To minimize
static charge:
◦ Provide a conductive path to ground from the metallic raised floor structure through the
metallic supporting structure or separately from each tile.
◦ Ensure the maximum resistance for floor surface material is 20 gigohms, measured between
the floor surface and building ground.
◦ The resistance between adjacent tiles should not be less than 150 kilohms when measured
between any points on the floor, spaced 91.5 cm (36 in) apart.
◦ Maintenance of antistatic floor covering should be performed according to supplier's
recommendations.
Hot-Aisle/Cold-Aisle Cooling Layout
Air flows through the storage systems from the front to the rear, so when installing multiple storage
systems in the same room, consider facing each pair of system in a front to rear configuration. This
allows cool air to be circulated through the rows in the front of the systems and exhausted through
rows in back. This is referred to as a hot-aisle/cold-aisle layout and eliminates the direct transfer
of hot exhaust air from one system into the intake air of another as shown in Figure 13 (page 24).
Establishing the Proper Foundation 23