Donald E. Ross
Retired Consultant
Jaros Baum & Bolles

Prior to World War II, air conditioning in much, if not all, of the United States was limited to movie theaters and similar areas of public occupancy. The Metropolitan Insurance Company's headquarters in midtown New York City, for example, was the only building in the city that was fully air conditioned at the time of its construction. Today, virtually every office building in the country is provided with full, all-season comfort conditions.

I entered the consulting engineering profession when the need to air-condition large office buildings was just beginning. I was also fortunate to do so in New York City, where so many of the early designs were constructed. In looking back on how the industry has changed since then, I can see the different forces behind some of the changes. Sometimes engineers were merely trying to improve on what was done in the last project. Other times technological advances in commercially available products resulted in new systems that were incorporated into a building. And some changes were driven by emerging needs of the public and resulting modifications in building codes.

Although the purpose of the mechanical and electrical systems for large office buildings has remained essentially the same over the last 100 years, the introduction of air conditioning fundamentally altered the architectural design and space usage of such buildings. These systems were and are intended to permit occupants to carry out their business in a productive, comfortable, and safe atmosphere. With the advent of air conditioning, though, each space no longer needed to be next to a window or have a means of providing natural ventilation. Architects could design buildings with large floor plates in which space 40, 50, or more feet from an exterior wall could be gainfully occupied by desks and workers and could even include private offices. The dramatic effect of this on architectural design cannot be overstated.

The past several decades have brought a number of smaller but equally significant changes in the design of the mechanical and electrical systems themselves. Energy-conserving designs, for example, significantly reduce the amount of energy consumed by a building. A building designed in the past decade uses less than half the energy consumed on a per-square-foot basis than a building designed in 1970. Revised and expanded building codes have improved the life safety systems that are mandated to protect both the occupants and the contents of a building in the event of a fire. Today, buildings can include new technology that features distributed intelligence in the form of personal computers and alternative telecommunications systems. And new air-conditioning systems provide greater comfort to occupants by allowing individuals to adjust their office environments to suit their own needs.

The systems-related design profession also recognizes that it must respond to environmental and "green" building concerns. These include, but are not limited to, energy conservation as an end in itself, indoor air quality, sustainable design considerations, and new technology that will better address the global environment of both the present and the future.

Addressing these issues—and success in obtaining real results—gives design engineers the satisfying sense of being part of a dynamic and meaningful area of engineering, one that meets the needs of a large segment of the population. I count myself fortunate to have been part of this ongoing process of improvement in the design of systems that meet the needs of the modern office building.