StorageTek SL8500, Руководство пользователя

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H
Controlling Contaminants H-1
H
Controlling Contaminants
This appendix explains controlling contaminants.
Environmental Contaminants
Control over contaminant levels in a computer room is extremely important because
tape libraries, tape drives, and tape media are subject to damage from airborne
particulates. Most particles smaller than ten microns are not visible to the naked eye
under most conditions, but these particles can be the most damaging. As a result, the
operating environment must adhere to the following requirements:
■
ISO 14644-1 Class 8 Environment.
■
The 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.
Oracle currently requires the ISO 14644-1 standard approved in 1999, but will require
any updated standards for ISO 14644-1 as they are approved by the ISO governing
body. The ISO 14644-1 standard primarily focuses on the quantity and size of
particulates as well as the proper measurement methodology, but does not address the
overall mass of the particulates. As a result, the requirement for total mass limitations
is also necessary as a computer room or data center could meet the ISO 14644-1
specification, but still damage equipment because of the specific type of particulates in
the room. In addition, the ANSI/ISA 71.04-1985 specification addresses gaseous
contaminations as some airborne chemicals are more hazardous. All three
requirements are consistent with the requirements set by other major tape storage
vendors.
Required Air Quality Levels
Particles, gasses and other contaminants may impact the sustained operations of
computer hardware. Effects can range from intermittent interference to actual
component failures. The computer room must be designed to achieve a high level of
cleanliness. Airborne dusts, gasses and vapors must be maintained within defined
limits to help minimize their potential impact on the hardware.
Airborne particulate levels must be maintained within the limits of ISO 14644-1 Class 8
Environment . This standard defines air quality classes for clean zones based on
airborne particulate concentrations. This standard has an order of magnitude less
particles than standard air in an office environment. Particles ten microns or smaller
are harmful to most data processing hardware because they tend to exist in large
numbers, and can easily circumvent many sensitive components' internal air filtration