HP Cluster Platform Site Preparation Guide

1.9.3 Other Environmental Considerations
The following environmental factors might also be important when planning an installation.
Electrostatic Discharge (ESD)
Static charges (voltage levels) occur when objects are separated or rubbed together. Low humidity
also contributes to undesirably high levels of electrostatic charges by increasing the electrostatic
discharge (ESD) voltage potential. Consider the following to reduce the risk of ESD:
• Maintain the recommended humidity level and airflow rates in the computer room.
• Install a conductive flooring (conductive adhesive must be used when laying tiles).
• If waxed floors are necessary, use a conductive wax.
• Ensure that all equipment and flooring are properly grounded and are at the same ground
potential.
• Use conductive tables and chairs.
• Use a grounded wrist strap (or other grounding method) when handling circuit boards.
• Store spare electronic modules in antistatic containers.
See Appendix E for specific permanent and temporary grounding requirements.
Electromagnetic and Radio Frequency Interference
Cluster components are tested and designed for global market and regulatory compliance, as
defined in the documentation for individual cluster components. Electromagnetic interference
(EMI) and radio frequency interference (RFI) are tested to ensure an equipment neutral installation.
When planning for a cluster installation, consider the impact of wireless communications such
as cellular telephones, wireless telephones, wireless LAN, WAN, and wireless security devices
that meet IEEE specifications 802.11 A, B, and G. Also consider the possibility of EMI or RFI
interference from systems adjacent to the new cluster installation; such devices might cause
undesirable effects in cluster components. Consider the following:
• All I/O cables, I/O assemblies, EMI or RFI enclosures, and component doors must be properly
secured and terminated to minimize the risk of interference.
• Do not use wireless transmission devices within 3 meters (10 feet) of cluster equipment,
including servers, mass storage, I/O cards, and I/O or power cables. This prohibition applies
to both cellular telephones and 802.11 wireless network equipment.
Within three meters of the cluster, you can use devices that meet the following specification:
— Have a power range of three volts per meter or less
— Operate at a frequency of less than 1 GHz
(The user is responsible for verifying the transmission power of low-power devices.)
Note:
Cellular telephones and similar radio frequency networked devices can emit a stronger
signal when hunting for a connection to a network cell. HP recommends that you always
switch off such devices when working in the proximity of a running HP Cluster Platform
system.
• Ensure that no motors or other electromechanical devices in the vicinity of the installed
cluster are shielded and generate no interference.
Other constraints might apply if you have an HP service contract, which might stipulate stricter
conditions on EMI and RFI under the terms and conditions of your service agreement.
Installation and Service Lighting
For safety and efficiency, HP recommends a minimum 70 foot candles (756 lumens) when the
light level is measured at 76.2 centimeters (30 inches) above the floor. Additional illumination
34 Installation Planning