The data center industry has experienced several evolutions over the past 20 years. One of the principal changes has been the development of the Tier Performance Standards. The standards provide quantifiable plateaus or Tier Levels. Tier Levels provide an objective basis for comparing the capabilities of a particular design topology against other designs as well as the associated site availability metrics for the various levels. The requirements of each Tier Level are clearly defined and provide a road map used in the design and management of the data center.
The Tier Level was developed in the early 1990s and is the foundation used by a number of data center owners/users, consultants and design professionals in establishing a “design-versus performance” ranking approach to today’s data center projects.
This paper will present a brief history of data center infrastructure topologies and their evolution, as well as a summary of the Tier Performance Standards and expectations, and endeavor to normalize several of the commonly used standards referenced in the industry today. The author proposes that the Tier Classification is the core for preparing the Owner’s Project Requirements (OPR) and Basis of Design for such projects and includes the provisions for the electrical, mechanical, environmental and data center infrastructure that is needed to meet a desired performance level.
A real-world project will be presented to illustrate a representative approach that is used in commissioning data centers today.