This is the first part of a three-part article about ADA-compliant hand dryers.

The Americans with Disabilities Act of 1990 (ADA) was designed, in part, to provide people with disabilities safe accessibility to public accommodations. The wide-ranging bill affected nearly every aspect of a building, down to basic fixtures like hand dryers in the restroom.

Under ADA regulations, any fixture that sits 27 inches or more above the floor must not protrude from the wall more than 4 inches. In the past, most facilities met the rules by mounting bulky dryers in a box that was then recessed into the wall. This “Band-Aid” approach is finally changing, however, as manufacturers now offer better, low-profile, surface-mounted dryers.

“By making them under 4 inches, they are ADA-compliant out of the box, without being retrofit,” says Rob Green, senior design engineer for Dyson, which has its U.S. headquarters in Chicago.

This year, the ADA turns 25. Manufacturers have been offering slim, compliant hand dryers for about 10 years. Despite the long history, sales of these machines have seen a serious uptick recently. There are several reasons for the renewed interest in a decades-old law.

“ADA compliancy standards are now more regulated,” says William Gagnon, vice president of marketing at Excel Dryer, in East Longmeadow, Massachusetts.

As the rules are more strictly enforced, facilities have a greater interest in upgrading their fixtures. Likewise, the public is demanding more forcefully (and more loudly, thanks to social media) that facilities of all types meet the standards.

Another important reason manufacturers now offer more compliant hand dryers is a rapid improvement in technology in recent years.

“The biggest technology change is the motor,” says Dan Storto, president of World Dryer in Berkeley, Illinois. “The motors are so much more advanced than 20 to 30 years ago. They are smaller and pack a bigger punch.”

Manufacturers are now able to produce dryer motors that are small enough to fit into a 4-inch footprint without sacrificing power. While old models typically drained 2,300 watts of energy per use, most new dryers clock in at less than 1,200 watts, and some at even less than 1,000 watts.

That dramatic bump in energy efficiency has facilities investing in slimmer hand dryers at a rapid rate, regardless of their interest in, or adherence to, ADA regulations.

“More commercial restrooms are adopting the technology for cost savings and energy-efficiency,” says Gagnon. “Restroom patrons also prefer high-speed, energy-efficient hand dryers that dry hands completely in 10 to 15 seconds, compared to the 45 seconds required by conventional hand dryers.”