This document addresses environmental control within data centres based upon the criteria and classifications for “availability”, “security” and “energy efficiency enablement” within EN50600-1. This document specifies requirements and recommendations for the following: temperature control; fluid movement control; relative humidity control; particulate control; vibration; physical security of environmental control systems. Safety and electromagnetic compatibility (EMC) requirements are outside the scope of this European Standard and are covered by other standards and regulations. However, information given in this European Standard may be of assistance in meeting these standards and regulations.