• Operating: +10° to +40°C (+50° to +104°F)
• Non-operating -40° to +60°C (-40° to +140°F)
Relative Humidity:
• Operating: 20% to 80% (40% to 50% recommended) non-condensing
• Non-operating: 10% to 95% non-condensing
Airborne Contaminants Limits
Maintain airborne contaminate levels below the limits to prevent equipment damage.
The operating environment for the library must meet to the following requirements:
• ISO 14644-1 Class 8 Environment
• Total mass of airborne particulates must be less than or equal to 200 micrograms
per cubic meter
• Severity level G1 per ANSI/ISA 71.04-1985
Particles ten microns or smaller are particularly harmful to most data processing
hardware. Gasses that are particularly dangerous to electronic components include
chlorine compounds, ammonia and its derivatives, oxides of sulfur, and petrol
hydrocarbons. In the absence of appropriate hardware exposure limits, health
exposure limits must be used.
Humidification with chlorinated water is a common source of airborne chlorine.
Appropriately-designed carbon filters must be used to ensure safe levels of airborne
chlorine when chlorinated water is used for humidification.
Table 2-1 Gas Limit Recommendations
Chemical ASHRAE OSHA (PEL) ACGIH NIOSH
Acetic Acid (CH
3
COOH) Not defined 10 ppm Not defined Not defined
Ammonia (NH) 3500 µg/m
3
350 ppm 25 ppm Not defined
Chlorine (Cl) 2100 µg/m
3
31 ppm (c) Not defined 0.5 ppm (c)
Hydrogen Chloride (HCl) Not defined 5 ppm (c) Not defined Not defined
Hydrogen Sulfide (H
2
S) 50 µg/m
3
320 ppm (c) 10 ppm 10 ppm
Ozone (O
3
) 235 µg/m
3
30.1 ppm Not defined Not defined
Petrol-hydrocarbons (C
n
H
n
) Not defined 500 ppm 75 ppm 300 ppm
Sulfur Dioxide (SO
2
) 80 µg/m
3
35 ppm 2 ppm 0.5 ppm (c)
Sulfuric Acid (H
2
SO
4
) Not defined 1 ppm Not defined 1 ppm (c)
Some basic precautions to follow:
• Do not allow food or drink into the data center.
• Do not store cardboard, wood, or packing materials in the data center clean area.
• Identify a separate area for unpacking new equipment from crates and boxes.
• Do not allow construction or drilling in the data center without first isolating
sensitive equipment. Dry wall and gypsum are especially damaging to equipment.
Chapter 2
Verify the Site Meets Environmental Requirements
2-2