IBM DS8882F, Introduction And Planning Manual

Page: 108 / 164

Table 46. Operational shock levels
Class Axis
g
1
pw
2
S1 Vertical 3.5 3.0
Notes:
1. g is the peak g level of an approximate half-sine pulse.
2. “pw” is the pulse width in milliseconds.
Contamination information
You must consider the air quality and contamination levels at your installation site.
Airborne particulates (including metal flakes or particles) and reactive gases that
act alone or in combination with other environmental factors, such as humidity or
temperature, might pose a risk to the storage system hardware. Risks that are
posed by the presence of excessive particulate levels or concentrations of harmful
gases include damage that might cause the system to malfunction or cease
functioning altogether. This specification presents 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.
Attention: In the absence of specific limits that are presented 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 damaged the storage
system, the warranty is void. Implementation of correctional measures is a
customer responsibility.
The following criteria must be met:
Gaseous contamination
Severity level G1 according to ANSI/ISA 71.04-1985
1
, which states that the
reactivity rate of copper coupons must be fewer than 300 Angstroms per
month (Å/month,
≈
0.0039 µg/cm2-hour weight gain)
2
. In addition, the
reactivity rate of silver coupons must be less than 300Å/month (
≈
0.0035
µg/cm2-hour weight gain)
3
. The reactive monitoring of gaseous corrosivity
is 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 selecting one of the following filtration methods:
v
The room air can be continuously filtered with MERV 8 filters.
v 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 must be more than 60% RH
4
. Data centers must be free of
zinc whiskers
5
.
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DS8882F Introduction and Planning Guide