In Universal Design, Comfort and Function for All

· Flexibility in use. Anticipate a wide range of preferences and skills by providing user adaptability -- for example, serving right- and left-handed people equally -- and optional methods of use.

· Simple and intuitive use. Avoid unnecessary complexity and make designs comprehensible, no matter what a user's experience, knowledge and language skills might be.

· Perceptible information. Communicate effectively with all users, whatever their sensory abilities and under all nominal conditions. This means employing multiple modes of expression -- graphic, verbal, tactile -- to achieve maximum clarity, legibility and speed of comprehension. (Designers of highway signs and image-and-data-dense Web pages should memorize this one.)

· Tolerance for error. Minimize hazards and adverse consequences of accidental or unintended actions, which is a basic objective in designing almost anything. This requires providing fail-safe features, clear warning signs and signals, understandable error messages and, most important, a logical, safe configuration of critical and noncritical components.

· Low physical effort. Design things to minimize physiological stress or fatigue during routine use. Avoid the need for unusual strength, sustained muscular effort, awkward body positions or excessively repetitive actions. (The rituals and tools for changing a flat tire come to mind.)

· Size and space for approach and use. Most closely paralleling ADA goals, this calls for places, spaces and devices to be proportioned to enable comfortable access, manipulation, use and operation, "regardless of user's body size, posture or mobility." It covers factors such as sight lines and variations in gripping ability.

These principles appear to be common sense. Yet homes, offices, furniture, appliances, and everyday tools and utensils, some thoughtfully conceived by designers and expensive to construct, are not universally user-friendly.

Therefore, achieving universal design objectives requires even more creative thought and often more initial investment.

Will universal design ever be legally required, like the ADA? Will it eventually become integral to America's design and production culture, just as the ADA became second nature to designers, almost a matter of ethics, after the first few years of whining by the building industry?

A federal requirement is unlikely. However, in light of economic and demographic projections, the American marketplace is likely to make universal design more universally embraced.

Roger K. Lewis is a practicing architect and a professor emeritus of architecture at the University of Maryland.