Does Temperature Affect Worker Productivity In India's Clothing Factories? : Goats and Soda Clothing factories in India can get pretty hot. How does that affect worker productivity? Researchers looked to the lights and gained an unexpected insight.

Why A Drop Of 4 Degrees Made A Big Difference For A Garment Maker's Bottom Line

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The hotter the temperature gets the more we seem to slow down. We are reminded of this every summer. It's hard to work, especially in places where there's no air conditioning. NPR's Nurith Aizenman reports on how one company hit on an unexpected solution. It's part of our summer series on heat.

NURITH AIZENMAN, BYLINE: The story of this discovery begins a few summers ago in the southern Indian city of Bangalore when an economist named Anant Nyshadham was heading to lunch with some executives at a garment factory.

ANANT NYSHADHAM: We walked through the factory floor on the way to the canteen. I thought, whoa, this is really hot.

AIZENMAN: And he grew up in Georgia. But in India - in fact, in a lot of developing countries - factories like this generally don't have air conditioning - too expensive.

NYSHADHAM: I mean, I can't imagine being able to do, like, work for eight hours a day in this environment.

AIZENMAN: And lab studies do suggest that once the temperature rises above around 85 degrees - this heat-stress threshold - our bodies start to warm up on the inside, and doing pretty much anything becomes more difficult.

NYSHADHAM: But it's a different thing to be able to show this in a real-world working setting versus at a laboratory.

AIZENMAN: But then Nyshadham, who's based at Boston College, hit on an unexpected way to do just such a real-world test when one of the executives at the garment factory let drop that...

NYSHADHAM: Oh, by the way, we've been rolling out this lighting change.

AIZENMAN: The company - it's called Shahi Exports - has got more than 50 factories, employs over 100,000 workers and supplies brands that include Gap, Uniqlo, Zara and H&M. Some of these brands had encouraged the company to be more environmentally responsible by switching out the fluorescent tube lights in its factories for LEDs that would consume about one-seventh the amount of energy. Nyshadham's reaction - this lighting switch was probably also going to lower the temperature on the factory floor.

NYSHADHAM: We realized, oh, we can use this as kind of like a natural experiment.

AIZENMAN: So over the next several years, Nyshadham and some collaborators started crunching the numbers. They compared the day-to-day relationship between the outside temperature and the number of garments produced at 26 different factories before and after their lights were switched to LEDs. Anant Ahuja is one of the managers at Shahi Exports who helped get this data to Nyshadham.

ANANT AHUJA: I was thinking that maybe he was wasting his time looking into this.

AIZENMAN: This is India. We're used to the heat. Then he saw the results.

AHUJA: I think all of us were kind of like, wow, that's amazing.

AIZENMAN: Nyshadham found that the mercury spiked above that heat-stress threshold - roughly 85 degrees inside the factory - a quarter of the time. And once it was passed that tipping point - for every extra degree it got hotter, productivity went down by 3 percent. And profits went down by 2.2 percent.

AHUJA: On the days it's hot enough to matter, it matters a lot.

AIZENMAN: One person who was not surprised to hear this...

MANJULA: Hi, madam. How are you?

AIZENMAN: That's Manjula, a seamstress at one of the factories. She's sitting in a long row of sewing machines.

MANJULA: (Laughter) Yes, ma'am.

AIZENMAN: What have you just been making?

MANJULA: Zip finishing on the...

AIZENMAN: Zip finishing she says - adding the zippers to some jeans for H&M. Manjula, who - like many Indians - goes by one name, has been doing this work for over a decade. She says it requires her maximum concentration.

MANJULA: (Speaking Kannada).

AIZENMAN: "The power in this machine," she says speaking the local language, Kannada...

MANJULA: (Speaking Kannada).

AIZENMAN: "If I'm not careful, I could break my finger or my hand."

MANJULA: (Speaking Kannada).

AIZENMAN: "And it's a problem when it gets really "hot." The sweat starts pouring down her face. She starts feeling tired, and sometimes she needs to take a break. Production slows.

MANJULA: (Speaking Kannada).

AIZENMAN: "But ever since the tube lights were swapped for LEDs," she says, she's noticed it's not as hot. And the production targets...

MANJULA: (Speaking Kannada).

AIZENMAN: "We've been achieving more of them," she says. In fact, the study found that the LEDs reduced the temperature on the factory floor by over 4 degrees. And the resulting boost to profits covered the cost of swapping in the LEDs in less than eight months. Now, Nyshadham says this study has implications well beyond this one company. It points up yet another potential downside of climate change - lost productivity.

NYSHADHAM: With rising temperatures - with the rising incidence of extreme temperature days, this is absolutely another avenue by which this has an impact on our lives - on the economic welfare of the world.

AIZENMAN: But he wants to focus on the other, happier takeaway from the study, which is that simple fixes like LED lights might have really big benefits. Nurith Aizenman, NPR News.


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