This topic identifies contamination information that pertains
to this product.
Airborne particulates (including metal flakes or particles) and
reactive gases acting alone or in combination with other environmental
factors, such as humidity or temperature, might pose a risk to the SAN Volume Controller hardware.
Risks that are posed by the presence of excessive particulate levels
or concentrations of harmful gases include damage that might cause
the SAN Volume Controller hardware
to malfunction or cease functioning altogether. This specification
sets forth limits for particulates and gases that are intended to
avoid such damage. The limits must not be viewed or used as definitive
limits because numerous other factors, such as temperature or moisture
content of the air, can influence the impact of particulates or environmental
corrosives and gaseous contaminant transfer.
In the absence of specific limits that are set forth in this document,
you must implement practices that maintain particulate or gas levels
that are consistent with the protection of human health and safety.
If IBM determines that the levels of particulates or gases in your
environment have caused damage to the SAN Volume Controller hardware,
IBM might require implementation of appropriate remedial measures
to mitigate such environmental contamination before providing
repair or replacement of the SAN Volume Controller hardware.
Implementation of such remedial measures is a customer responsibility.
The following criteria must be met:
- Gaseous contamination
- Severity level G1 as per ANSI/ISA 71.04-19851, which
states that the reactivity rate of copper coupons shall be less than
300 Angstroms per month (Å/month, ≈ 0.0039 μg/cm2-hour weight gain)2.
In addition, the reactivity rate of silver coupons shall be less than
300Å/month (≈ 0.0035 μg/cm2-hour weight gain)3. The reactive
monitoring of gaseous corrosivity should be conducted approximately
2 inches (5 cm) in front of the rack on the air inlet side at one-quarter
and three-quarter frame height off the floor, or where the air velocity
is much higher.
- Particulate contamination
- Data centers must meet the cleanliness level of ISO 14644-1 class
8. For data centers without airside economizers, the ISO 14644-1 class
8 cleanliness can be met by choosing one of the following filtration
methods:
- The room air can be continuously filtered with MERV 8 filters.
- Air entering a data center can 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 cleanliness depends on the specific conditions
present at that data center. The deliquescent relative humidity of
the particulate contamination should be more than 60% RH4.
Data centers must be free of zinc whiskers5.
- ANSI/ISA-71.04.1985. Environmental conditions for process
measurement and control systems: Airborne contaminants. Instrument
Society of America, Research Triangle Park, NC, 1985.
- The derivation of the equivalence between the rate of copper corrosion
product thickness growth in Å/month and the rate of weight gain assumes
that Cu2S and Cu2O grow in equal proportions.
- The derivation of the equivalence between the rate of silver corrosion
product thickness growth in Å/month and the rate of weight gain assumes
that Ag2S is the only corrosion product.
- The deliquescent relative humidity of particulate contamination
is the relative humidity at which the dust absorbs enough water to
become wet and promote corrosion, ion migration, or both.
- Surface debris is randomly collected from 10 areas of the data
center on a 1.5 cm diameter disk of sticky, electrically conductive
tape on a metal stub. If examination of the sticky tape in a scanning
electron microscope reveals no zinc whiskers, the data center is considered
free of zinc whiskers.