The standards were first published in 2004, and in 2008 expanded the recommended temperature and humidity ranges. The recommended temperatures have not been changed for this edition, but include new data center environmental classes that enable near-full-time use of free-cooling techniques in most of the world's climates. Also retained is the cornerstone idea that inlet temperature is the only temperature that matters to information technology equipment. A glance to the future is included, when increased density of machinery will make liquid cooling more cost effective than the air cooling used almost exclusively now. A reference card to stay on site is provided. There is no index Annotation ©2012 Book News, Inc., Portland, OR (booknews.com)
