In the beginning, in offices, there were men in suits. And ties and calf-length dress socks and shirts buttoned all the way up top. In other words, men perfectly comfortable with having the air conditioning on full blast.
And so, as anyone who has suffered in frigid offices can attest, that became the standard in office buildings.
In the academic world of “thermal-comfort” research, men in suits became the standard, too. The mathematical models for thermal comfort assumed as much. As more women entered the workforce, researchers caught up to study women’s clothing. But in recent years, an even bigger change is afoot: Thermal comfort research is shifting to the developing world. And western clothing is no longer the only standard.
The problem is obvious by the numbers. Buildings already consume 40 percent of the world’s energy, and half of that goes into keeping them warm or cool. And western countries eat up the vast majority of that. “If the developing world follows U.S. traditional practice, it’s going to be energy-intensive,” says Edward Arens, who studies thermal comfort at the University of California, Berkeley. (The world will install 700 million more AC units by 2030, if current trends continue.) In other words, if the hundreds of millions of people who currently live without indoor heat or air conditioning follow the west’s wasteful standards, Earth is boned.
So while “thermal comfort” sounds like a phrase you might find in a spa ad, the study of more energy-efficient ways to keep people cool in the summer and warm in the winter has huge implications for Earth’s future. And you could start by making thermal-comfort models reflect the world—the whole world—a little better.
That’s how, a few years ago, George Havenith, an environmental ergonomist at Loughborough University in the United Kingdom, found himself figuring out how to order custom-made clothes from Indonesia. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), which sets standards in the U.S. that influence the rest of the world, assigns articles of clothing an insulation value in units of “clo.” A bra is 0.01 clo; a double-breasted jacket is 0.44 clo. The original list is, unsurprisingly, western-centric. A few years ago, ASHRAE funded a project, led by Havenith, to assign insulation values to non-western clothing like saris, hijabs, and abayas.
A better understanding of how non-western clothing keeps people warm or cool could translate to energy savings: If a loose-fitting Indian outfit is cooler than a western men’s suit, buildings don’t need to be cooled to the same (very cold) western standard.
The first step was actually collecting all the clothes to study, so Havenith’s U.K. lab along with collaborators in Sweden and Hong Kong hit up all their contacts. The Swedish group found a shop in Sweden where they could order African clothing. A nearby city in the U.K. had a big Indian and Pakistani community, where the lab could shop for clothes from the subcontinent. And the Indonesian outfits they got get custom made in Indonesia; the western mannequins were too big to fit typical Indonesian sizes.
For several months—in three labs in the U.K., Sweden, and Hong Kong—researchers dressed and undressed special thermal mannequins to test the warmness of different outfits. The mannequins looked a lot like ones you’d see in a department store, but their bodies hid complicated electrical wiring. Just as the human body burns calories to keep us at 98.6 degrees Fahrenheit, the mannequins draw electricity to maintain a certain temperature. The less insulation the clothes provide, the more electricity they use.
The mannequins also had to “sweat,” since that’s a major way humans lose heat. “We would wet the skin with a spray can and after an hour and a half, you have to undress it and rewet it,” says Havenith. Other models of thermal mannequins have dozens of “sweat glands” controlled by a water pump. Studying how well sweat evaporates off with these outfits is actually pretty key: Non-western clothing tends to be looser-fitting and more breathable.
In the end, the team came up with insulation values for 52 outfits in total, including ones that would be typical for a man in Ghana or a woman in Kuwait. The gallery of mannequin photos resembles a department store, if the department store were somehow awkwardly Epcot-themed. It’s not that every single outfit on the list necessarily represents typical office clothes in a given country—the qipao, a skintight silk gown, is not exactly the equivalent of business casual in China—but they do dramatically broaden the clothing models thermal comfort researchers can use. The developing world, long-neglected in thermal research, is finally gaining attention.
Thermal comfort researchers in India and China have started to integrate the new insulation values into their research. A man in a suit is no longer the default. And freezing offices will, hopefully, no longer be the default. For the Earth’s sake and ours.