2.2.4.
Air Pollutants
There are three types of pollutants:
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liquids,
solid particles,
gases.
Damage varies according to pollutant type and interaction: corrosion, erosion, mildew,
oxidation, etc.
Solid particles are abrasive, electrostatic, and absorbent. They generally originate from:
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•
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surface crumbling of construction materials used to fit out the Data Processing Center,
the formation of rust inside air conditioning units and on raised floor supports,
systems (e.g. printers, ...),
insufficient filtering of fresh air,
personnel.
Polluted air results in:
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clogged filters and impaired thermal dissipation,
damaged connections (contact points) = intermittent failures,
deterioration of magnetic media,
premature wear and tear of components and moving parts.
Note
The Computer Room and ancillary premises must be cleaned thoroughly at frequent
intervals. See Cleaning, on page 1-13 for further details.
Gas pollution is difficult to control.The known effects of gas pollution on equipment and
hardware are corrosion and oxidation.
CAUTION
In a standard data processing environment, gas concentration does not exceed an
acceptable level. However, if there are chemical or industrial processing factories in the
vicinity, if chemical odors are present, or if any other symptom or inherent problem is
detected, the site must be analyzed immediately.
2.3.
Checks and Alarms
The air-conditioning system is controlled automatically. Variations outside the specified
temperature and hygrometry ranges must be reported to support personnel.
Detectors must be installed in a place not subjected to cold or hot airflow or climatic
variations. Alarms must indicate any variation outside the specified Computer Room climatic
environment conditions.
A weekly thermo-hygrograph recording sheet must be displayed so that any disruptions in
the air-conditioning system can be viewed and recorded. Thermo-hygrograph recording
sheets must be archived for at least three months.
An alert system must be installed to report if ambient temperature exceeds the critical
threshold of 25/26°C. This pre-alarm system should be coupled with an intervention
procedure aimed at repairing faults in the Computer Room air-conditioning system.
mportant We strongly recommend the installation of a dynamic safety device to
automatically cut off the electric power supply to equipment if ambient
temperature exceeds the critical threshold of 30°C.
Chapter 2.
Air-Conditioning
2-5
Summary of Contents for CX1000
Page 1: ...Site Preparation Guide ...
Page 56: ...Cray ...
