Lenovo ThinkSystem DW612S System Configuration Manual

Table 1. Limits for particulates and gasesContaminant LimitsReactive gases Severity level G1 as per ANSI/ISA 71.04-19851:• The copper reactivity level shall be less than 300 Angstroms per month (Å/month ≈ 0.0039 μg/cm2-hour weight gain).2• The silver reactivity level shall be less than 200 Å/month (Å/month ≈ 0.0035 μg/cm2-hourweight gain).3• The reactive monitoring of gaseous corrosivity must be conducted approximately 5 cm (2 in.) infront of the rack on the air inlet side at one-quarter and three-quarter frame height off the flooror where the air velocity is much higher.AirborneparticulatesData centers must meet the cleanliness level of ISO 14644-1 class 8.For data centers without airside economizer, the ISO 14644-1 class 8 cleanliness might be met bychoosing one of the following filtration methods:• The room air might be continuously filtered with MERV 8 filters.• Air entering a data center might be filtered with MERV 11 or preferably MERV 13 filters.For data centers with airside economizers, the choice of filters to achieve ISO class 8 cleanlinessdepends on the specific conditions present at that data center.• The deliquescent relative humidity of the particulate contamination should be more than 60%RH.4• Data centers must be free of zinc whiskers.51 ANSI/ISA-71.04-1985. Environmental conditions for process measurement and control systems: Airbornecontaminants. Instrument Society of America, Research Triangle Park, North Carolina, U.S.A.2 The derivation of the equivalence between the rate of copper corrosion growth in the thickness of the corrosionproduct in Å/month and the rate of weight gain assumes that Cu2S and Cu2O grow in equal proportions.3 The derivation of the equivalence between the rate of silver corrosion growth in the thickness of the corrosionproduct in Å/month and the rate of weight gain assumes that Ag2S is the only corrosion product.4 The deliquescent relative humidity of particulate contamination is the relative humidity at which the dust absorbsenough water to become wet and promote ionic conduction.5 Surface debris is randomly collected from 10 areas of the data center on a 1.5 cm diameter disk of stickyelectrically conductive tape on a metal stub. If examination of the sticky tape in a scanning electron microscopereveals no zinc whiskers, the data center is considered free of zinc whiskers.Management optionsThe XClarity portfolio and other system management options described in this section are available to helpyou manage the servers more conveniently and efficiently.4 ThinkSystem DW612S Neptune DWC Enclosure System Configuration Guide