Inside Science 251, a workshop filled with bolts, ball bearings and wheels of various sizes, Marc Krizack unfolds a RoughRider wheelchair and raises it above his waist.

"This chair is designed to be dropped from the height of a car trunk," he says. "Even in the worst conditions in developing countries, you aren't going to make this break."

The sturdy chair is the latest model from Whirlwind Wheelchair International. Whirlwind, a program of the SF State Institute for Civic and Community Engagement, creates wheelchair designs specifically for people with disabilities in developing countries, where a typical day can involve traversing steep curbs, rocky roads, muddy fields and other treacherous terrain. Wheelchairs are manufactured in Whirlwind workshops in more than 20 developing countries on nearly every continent -- all by the hands of residents who use locally available parts and materials.

In order to keep the prices as low as possible--the price to build each chair can range anywhere from $105 in Vietnam to $300 in Africa -- Whirlwind keeps its designs in the public domain. "We support local economic development in these countries where people with disabilities are the poorest of the poor," says, Krizack, Whirlwind's director of operations.

Founded by Peter Pfaelzer and Ralf Hotchkiss in 1989, Whirlwind was recently singled out for its ability to "substantially improve important aspects of human life." The RoughRider was among 110 nominees vying for a 2007 INDEX: AWARD for the world's best "designs for life."

Hotchkiss, a MacArthur "Genius" award recipient, designed the RoughRider with colleague Chris Howard. Whirlwind staff and engineering students have helped make adjustments and continue to improve the chair's functionality. Helpful feedback also comes from wheelchair users who test Whirlwind prototypes.

A number of factors go into worldwide wheelchair design. There's gender (women's hips tend to be wider than their shoulders which can affect their arm reach), the location it will be used in (adjustable parts can be ideal for areas where replacements are hard-to-come by) and cultural and social considerations (it's important to know how riders spend their days whether cooking or working on a floor), just to name a few.

Unlike standard wheelchairs, the RoughRider is designed to roll over rocks and divets.  It has mountain bike tires in the back and front wheels with a wide, flexible tread that glide over soft or uneven ground. A long wheelbase allows users to push the wheels without unnecessary strain. Toe protectors shield bare feet from rocks and other debris.

"The best part is that it frees a person's mind to think about other things," Krizack says. "Wheelchair riders are always looking down at the ground in front of them, making sure they don't run into something. Once they don't have to do that, their lives change."

Next up: a RoughRider designed to grow along with children who have disabilities. The first models are expected in Columbia this October. Says Krizack, "We're never done."

-- Adrianne Bee