HP xw2x220c Blade manual Electrostatic discharge prevention, Acoustic noise specification

Electrostatic discharge prevention

Static charges (voltage levels) occur when objects are separated or rubbed together. The voltage level of a static charge is determined by the following factors:

•Types of materials

•Relative humidity

•Rate of change or separation

Follow these precautions to minimize possible ESD-induced failures in the computer room:

•Maintain recommended humidity level and airflow rates in the computer room.

•Install conductive flooring (conductive adhesive must be used when laying tiles).

•Use conductive wax if waxed floors are necessary.

•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.

Acoustic noise specification

Declared noise emission values for the c7000 enclosure in accordance with ISO 9296:

Specification	Value
Declared sound power level, LWAd Bels
Idle	7.5
Operating	7.5
Declared sound pressure level, LpAm dBA
Idle	57
Operating	57

Detailed information on conformance to country Technical Regulations and certificates of conformance can be found on the HP website (http://www.hp.com/go/certificates).

These levels are appropriate for dedicated computer room environments, not office environments.

You must understand the acoustic noise specifications relative to operator positions within the computer room when adding additional systems to computer rooms with existing noise sources.

Ambient noise level in a computer room can be reduced as follows:

•Dropped ceiling—Cover with a commercial grade of fire-resistant, acoustic rated, fiberglass ceiling tile.

•Sound deadening—Cover the walls with curtains or other sound deadening material.

•Removable partitions—Use foam rubber models for most effectiveness.

Environmental requirements 17