scope:

Overview

Environmental requirements of datacom equipment vary depending on the type of equipment and/or manufacturer. However, a consortium of server manufacturers has agreed on a set of four standardized conditions (Classes 1 to 4), listed in Thermal Guidelines for Data Processing Environments (ASHRAE 2008). A fifth classification, the Network Equipment-Building Systems (NEBS) class, is typically used in telecommunications.

• Class 1: typically a datacom facility with tightly controlled environmental parameters (dew point, temperature, and relative humidity) and mission-critical operations; types of products typically designed for these environments are enterprise servers and storage products.

• Class 2: typically a datacom space or office or lab environment with some control of environmental parameters (dew point, temperature, and relative humidity); types of products typically designed for this environment are small servers, storage products, personal computers, and workstations.

• Class 3: typically an office, home, or transportable environment with little control of environmental parameters (temperature only); types of products typically designed for this environment are personal computers, workstations, laptops, and printers.

• Class 4: typically a point-of-sale or light industrial or factory environment with weather protection, sufficient winter heating, and ventilation; types of products typically designed for this environment are point-of-sale equipment, industrial controllers, or computers and handheld electronics such as PDAs.

• NEBS: per Telcordia (2001, 2006), and typically a telecommunications central office with some control of environmental parameters (dew point, temperature and relative humidity); types of products typically designed for this environment are switches, transport equipment, and routers.

Because Class 3 and 4 environments are not designed primarily for datacom equipment, they are not covered further in this chapter; refer to ASHRAE's (2008) Thermal Guidelines for Data Center Environments for further information.