On Tuesday morning, the phone at Torana Clean Air Center was ringing off the hook. As China’s capital woke up to its first-ever “red alert” for smog, the skies outside were a noxious gray, but the air inside the small storefront was crisp and clean, alive with the mechanical whirring of several air purifier machines.

“I’ve already sold seven machines worth 30,000 renminbi,” or about $4,700, said shopkeeper Yuan Yuxia as she tried to keep up with the steady stream of customers pushing through the door just 90 minutes after the shop opened. Pressing a button on her answering machine, her eyes popped. “I’ve got 31 messages to return.”

Among those waiting in line was Lampel Joy Solis, a Filipino who teaches kindergarten in Beijing. When municipal authorities announced the red alert on Monday evening, Solis, like many Beijing residents, was caught off guard.

Few in this city of 20 million were unaffected by the alert's attendant measures: The vast majority of schools, hers included, were closed for the day; construction sites were shut; only cars with even-numbered license plates were allowed on the roads during the day.

The city has previously taken serious precautions to ensure clean air ahead of high-profile international events including last year’s Asia-Pacific Economic Cooperation summit and September’s military parade. But this was the first time authorities had imposed such controls during an ordinary week, giving citizens just 13 hours’ notice to make child-care arrangements and find new routes to work.

“I think this red alert is good for awareness,” said Solis, a seven-year Beijing resident, as she purchased a new $50 filter for her home machine. “It shows that they recognize it’s a problem — before, it was just like, ‘This is part of the normal development of the country.'"

There seemed to be a sense Tuesday that Beijing had crossed a Rubicon. Optimists like Solis smelled change in the smoky air, saying the alert demonstrated a new political will to grapple with a grave public health issue after years of denial and neglect. Others with a darker view said the emergency measures were simply proof of how grim the situation had become, and questioned whether they would have any significant impact on air quality.

“I first heard about the red alert from my friends; I thought they were just kidding because there isn’t any big conference or ceremony like APEC or military parade in the next few days,” said Wang Yanqiang, 23, a full-time Uber driver. “But then the news notification popped up on my cellphone and confirmed this.

“The measures ask too much from drivers because the primary factor leading to the smog is not vehicles,” he continued. “You can see the smog isn’t going away when only half of the cars are allowed on street. I remember they closed a lot of factories before the military parade, and that should be the most effective way to control the air pollution, not traffic controls like this.”

A red alert is supposed to be issued when forecasters predict the Air Quality Index (AQI) – a measure of air pollution with a scale of zero to 500 -- will stay above the 300 mark, considered “hazardous” by the World Health Organization, for 72 hours straight. A forecast for even more severe pollution expected to last for a shorter period would not trigger such an alert.

Last week, the capital endured five days of intense air pollution – some monitors read “beyond index” as the AQI climbed to nearly 600. However, city officials defended their decision not to issue a red alert then, noting that pollution readings had briefly dipped into the marginally better “unhealthy” range.

Since the beginning of 2015, Beijing has already endured 10 days where the AQI climbed into “severe” territory.

With the red alert restrictions set to last through Thursday, Beijingers were contemplating how frequently they would have to endure such limits going forward, how they would cope with the inconveniences, and the health effects of living amid constant bouts of toxic air.

“If these traffic restrictions can really solve the smog problem and make the air in Beijing clean, I'm willing to face such limits on a daily basis,” said Ma Qiansen, 25, who works for an advertising company and was commuting by subway Tuesday because he was not permitted to drive. “But I don't think the restrictions will work, because shouldn't all the gas used in the cars [already] be approved by the government and be clean?”

Outside of the Beijing Children's Hospital in the west of Beijing, Zhang Jiaying, 34, was holding her 5-year-old son's hand and waiting for their appointment in the respiratory department. Her son, she said, had been coughing for five days straight. He was wearing a children's mask, his face turning red as he tried to suppress his fits.

“I feel helpless,” said Zhang, a math teacher. “Maybe my son's sickness isn't directly caused by the smog. But as a parent, I cannot help wondering what if my kid could grow up in a much cleaner environment? What if he had the choice of breathing cleaner air? Would he still fall sick so easily? Would he still cough nonstop?

“Kids these days fall sick much more easily than we did when we were kids, yet we were not as wealthy as them, and we certainly didn't enjoy as much convenience,” she added. “But health is the most important for children, right? Without health, the convenience and facilities are just nothing."

A gas station worker, who gave his name only as Mr. Zhang, praised the government for issuing the alert.

“This time, the Beijing government’s reaction speed should be hailed. It was fast, wasn’t it?” he said, standing near the pumps without a mask on.

“I still need to work,” he said, but “I feel relieved about the schools’ cancellation of classes, because my daughter can stay at home and I don’t need to worry about her breathing bad air.”

When the U.S. Embassy in Beijing began issuing pollution readings several years ago, Chinese state media – and many ordinary Chinese – accused Ambassador Gary Locke of “meddling” in the nation’s internal affairs or seeking to embarrass the Communist Party.

On Tuesday, however, even the previously dismissive Global Times, a nationalist tabloid affiliated with the Communist Party, was taking a bit of a new tack, noting that the American data as well as a chorus of complaints from online commentators known as “big voices” or “big Vs” had spurred the government to act.

“It’s taken just a few short years to go from repudiating PM2.5 [data] to today issuing a red alert — this is a near-revolutionary change. The U.S. Embassy and some of the ‘big Vs’ also made positive contributions,” editor Hu Xijin posted to his official microblog account. “This is one example of working together to promote the progress of China, and shows the country can absorb constructive criticism and adapt.”

Nicole Liu, Tommy Yang, Yingzhi Yang and Alexandra Li in the Times' Beijing bureau contributed to this report.

Follow @JulieMakLAT and @JRKaiman on Twitter for news out of Beijing.

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