DETROIT — When it comes to uniforms, Sally Hotter has sported some awkward ones.

There was the Taco Bell uniform with the stiff burgundy pants and the shirt that made her sweat.

"For lack of a better word, it was dorky," said the 26-year-old United Parcel Service driver from St. Clair Shores, Mich.

When she became a medical receptionist, she wore scrubs that she said were comfortable but unflattering.

So Hotter was skeptical about how she'd feel when she slipped on her UPS driver browns three years ago.

"It's actually flattering and functional," said Hotter. "I'm only 5-foot-3, and I'm surprised they fit me. They're very proportional to my body. All the pockets are in the right places."

Getting those browns to look and feel good has been an ongoing process since 1907, when UPS drivers first put them on. UPS, a company that likes a conservative yet modern look, makes tweaks to its uniforms almost every year.

Garb updates are becoming more frequent for the nation's 32 million uniform wearers.

Businesses used to update uniforms every five to seven years, but it's now more common for revisions to happen every three years, said Andy Beattie, senior vice president of the school and service apparel division of Strategic Partners, a uniform manufacturer in Chatsworth, Calif.

Advances in fabric technology and design — and the realization that workers and their uniforms are the face of a company — are among reasons for the shift. Companies also realize that uniforms affect morale and motivation, which ultimately affects the bottom line.

"They're changing more and more often so employees who meet the public have an opportunity to not look so dated," Beattie said. "It improves their image, the company's branding and, in turn, they feel better about the way they look and feel more successful."

Big-name retailers such as Wal-Mart are dumping aprons for a trendier look. The company said in October that it started testing a new uniform to attract more upscale shoppers. The new duds consist of a plain dark-blue shirt and khaki plants. They contrast sharply with the lettered smocks workers have been wearing.

The U.S. Army went to a digital print in 2004 that adapts more readily to soldiers' changing environments. The Army also now uses Velcro to keep shirt pockets shut instead of buttons, which ripped off easily and needed frequent repairs.

Last week, Northwest Airlines officials said they are considering new flight attendant uniforms. The uniform was last changed 14 years ago, said spokesman Roman Blahoski.

Although companies say they're attempting to make workers more stylish, they're also changing uniforms to be more comfortable and ergonomically friendly.

The latest uniforms for 85,000 UPS drivers worldwide provide reflective threads for safety, have zippers in the armpits for ventilation and offer brown turbans to workers whose religious and cultural affiliations require them. The company also said it offers alternative fabrics for workers who have allergies.

"We are in constant communication with the garment manufacturing industry and with suppliers to keep us up to date on what the latest options are," said spokeswoman Diana Hatcher.

Strategic Partners said it's also important to have a little fun with fabrics. For instance, the company said it's making hospital scrubs available in many colors and designs instead of the traditional green or blue.

Scrubs made by Strategic Partners are available in more than 40 prints, including Scooby-Doo, Hello Kitty, Betty Boop, SpongeBob Squarepants and Peanuts.

In January, the company will debut a hip-hop scrub designed by BabyPhat.

The scrubs have a slim fit, unique colors and some bling in the silhouettes and treatments, said Susan Nunez, executive vice president for that line.

"One of the things we want to do is bring some laughter into hospitals and put a smile on people's faces," she said.

Margaret D. Mitchell, a former flight attendant with USAir, said she would have welcomed more frequent changes to the uniform she wore for 16 years. Northwest's move toward new uniforms is particularly notable because the airline industry has been notoriously slow about updating garbs.

"I felt like mine was made of titanium," said Mitchell, who retired in October 2005 and currently lives in Atlanta. "You could drop all kinds of food and gravy, and you could just wipe it off. I'm telling you, I never got a stain on it. They should make sofas and carpets out of that stuff."