Influential companies setting the snooze alarm these days include Google, The Huffington Post, Time Warner, Nationwide Planning Associates, Proctor & Gamble, Mimecast, Ben & Jerry's, Zappos, Nike, Pizza Hut, AOL, and MetroNaps, just to name a few.

Much of corporate America has yet to sign on to the napping revolution, according to the 2014 Employee Benefits Survey released by the Society of Human Resource Management. Just 3 percent of the survey's 510 respondents said they offered nap rooms, and none of the respondents who currently did not provide the perk said they had plans to offer the benefit sometime in the future.

But those companies who are ahead of the curve when it comes to on-the-job snoozing can rest assured they have the data to back the decision up: Decades of sleep research by the National Sleep Foundation, NASA, the National Transportation Safety Board, and scores of academic and medical researchers have unequivocally shown that a brief 20–30 minute nap can result in the following beneficial effects:

• Increase alertness       
• Reduce accidents
• Improve judgment
• Boost creativity
• Improve learning and memory
• Reduce stress
• Control blood pressure
• Increase reaction time
• Control weight
• Improve mood and energy levels

Regardless of the benefits, however, the stigma of catching a few Z's in a company without a formal nap policy can be severe, subjecting employees to ridicule from peers and, worse, career-blunting labels like unproductive, lazy, and ambitionless from managers.

Yet many employees keenly aware of both the stigma and potential harm to their reputations still find ways to sleep during the workday. Some curl up in their car during lunch breaks. Others become stallnappers, a term coined by authors Camille Anthony and William Anthony in their book, The Art of Napping at Work, to describe employees who sneak off and hide in a bathroom stall to catch a quick 40 winks.

And if employees aren't actually closing their eyes and drifting off someplace out of view, they're right there at their desks where they belong, too fatigued to do anything more than pretend to be productive.

"Employees are hiding their naps from their colleagues, who are hiding their naps from them. And their bosses and supervisors are too tired to notice," note the authors.

In 2007, Arianna Huffington hardly noticed what she was doing to herself. The Huffington Post founder was logging 18-hour days to ensure the success of her then 2-year-old publishing venture when she fainted and came to in a pool of her own blood, the result of a broken cheekbone and a cut over her eye. After weeks of medical tests ruled out the most worrisome possibilities, doctors determined she had simply collapsed from overwork and exhaustion.

Insufficient sleep and workaholism, Huffington realized, were not the friends of sustained and consistent productivity. As a consequence, today the company's New York headquarters, as well as some of its overseas facilities, include nap rooms and even beds. "They are always full," she says.

If a nap room is beginning to sound like a good idea — except for the word "nap" —  no need to employ those three loaded letters.  Take the approach of many companies and call it a "meditation," "quiet,"  "relaxation" or "rejuvenation" room.

The rooms themselves run the gamut from utilitarian to luxurious. Google, needless to say, goes all out, providing employees at various facilities around the world with top-of-the-line shut-eye that, depending on the particular office, may include dedicated relaxation rooms featuring low lighting, built-in aquariums and the $9,000–$13,000 EnergyPod, a special high-end sleep chair made by a company called MetroNaps.

The EnergyPod, also used by Cisco and Proctor & Gamble, looks like a combination chaise lounge and football helmet for practically the entire body. It allows the user to shut out the world by pulling down a visor on the helmet part of the chair, turning on the Bose speakers for music or soothing sounds, and then drifting quietly off with Mr. Sandman. But not for too long. The chair offers timed wakeup with gentle vibrations and, mirroring a morning sunrise, slowly intensifying light.

"No workplace is complete without a nap pod," says David Radcliffe, vice president of Google's Real Estate & Workplace Services.

While it might be nice to hop in your Lamborghini to pick up take-out, you can get the chow just as quickly in a Chevy. For less than the cost of one EnergyPod, James Colleary, a compliance principal at Nationwide Planning Associates, Inc., a 20-employee, Paramus, New Jersey, investment firm, had an unused closet remodeled and outfitted with a recliner, fountain, and bamboo rug. Voila, rejuvenation room! Employees sign up for 20-minute blocks of nap time. During busy or short-staffed situations, however, employees understand that they may have to forgo their nap that day.

Boston-based marketing-software company HubSpot didn't even bother with a recliner. The nap room for its 750 employees offers a red hammock poised above a plush carpet and four walls painted with a couple of palm trees sprouting from a sandy beach. Puffy white clouds join the trees and float in a turquoise sky above a calm, azure sea.

One well-known New York publishing house doesn't bother with anything. Employees are permitted to catch a nap by ducking behind divider screens in the office or curling up under their desks with a yoga mat.

For companies that don't mind employees napping but don't want to get involved at all, there's the Ostrich Pillow, a soft, comfortable, light-blocking cloth sack with a hole in the front for breathing and holes at the side for hands to slip inside and support a sleepy head. An employee slips the sack over the head and can then crash out comfortably right there on the desk.

Cost to the employee: under a hundred bucks and most likely a spate of amusing photos posted around the office and on Facebook with one's head stuck in a silly-looking sack.

Not for everyone

Not everyone, though, believes in the power of the power nap. Nabeel Mushtaq, chief operating officer and co-founder of AskforTask.com, a small Toronto company that connects people who need various tasks done with people willing to do them, decided to set up a nap room for his programmers, many of whom were working as much as 70 hours per week. Though napping was limited to 15 minutes, many employees accidentally overslept and returned to work groggy and more fatigued then they were before the break.

Moreover, in order to recover from the nap, employees hit the restroom to splash water on their face and then returned to make a cup of coffee, adding anywhere from 30 to 90 minutes to the whole process, notes Mushtaq. Six months into the program, employees were reaching only 55 percent of their weekly goal, down 30 percentage points from before the sleep experiment. Mushtaq ended the program.

"We still have the nap room," says one employee, "but nobody uses it."

Read: No room for sleep deficiency on the job

A workplace nap really shouldn't last longer than 20–30 minutes, caution sleep researchers. Sleeping longer than that, as AskforTask.com discovered, triggers deeper sleep stages and the employee often wakes up bleary-eyed, slow, and worse off than before the nap. Because caffeine tends to kick in about 20 minutes after it enters the system, a cup of coffee before the nap, researchers say, can help prevent over-napping,

To foster the success of a nap-room program, experts tend to agree on several points:

• Build a separate room for napping.
• Choose a space without windows or use light-blocking shades.
• Paint the room in cool, restful colors like blue, green and violet.
• Sofas, beanbag chairs and air mattresses are good alternatives to more expensive chairs.
• Establish napping as part of the company culture.
• Encourage appropriate napping. Longer than 30 minutes results in the beginning of deeper sleep, which is harder to rouse from. Employees should understand that imminent deadlines, for example, might not be the best time to insist on a nap.
• Avoid policies that mandate when employees can nap. The need for rest varies among individuals.

But as Arianna Huffington discovered, prioritizing a good night's sleep might be the best and simplest way to recover from periods of overwork and remain consistently alert and productive on the job.

Dr. Carol Ash, a consultant to Fortune 500 companies and director of Sleep Medicine at Meridian Health System in New Jersey, offers a few tips to ensure a decent night's sleep and productive next day.

• Get between seven and nine hours of sleep a night.
• Go to bed and wake up at the same time, even on the weekends.
• Don't nap for more than 20 minutes.
• Turn off electronics an hour before bed.
• Keep your room dark, quiet and cool, preferably between 65 and 70 degrees.
• Avoid spicy food. Avoid alcohol at least three hours before sleep. Avoid caffeine at night.

One final note. In 1999, William Anthony, a Boston University professor and his wife Camille, designated August as National Nap Month, an unofficial, pillow-in-cheek holiday meant to call attention to the benefits of napping. The nice thing about this holiday? You can celebrate it any time of the year.