Particulate 
contamination
Specifications
NOTE: Air entering the data center must have MERV11 or MERV13 filtration.
Conductive dust Air must be free of conductive dust, zinc whiskers, or other conductive particles.
NOTE: Applies to data center and non-data center environments.
Corrosive dust
• Air must be free of corrosive dust.
• Residual dust present in the air must have a deliquescent point less than 60% 
relative humidity.
NOTE: Applies to data center and non-data center environments.
Gaseous 
contamination
Specifications
Copper coupon 
corrosion rate
<300 Å/month per Class G1 as defined by ANSI/ISA71.04-1985.
Silver coupon 
corrosion rate
<200 Å/month as defined by AHSRAE TC9.9.
NOTE: Maximum corrosive contaminant levels measured at ≤50% relative humidity.
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