BEIJING — The Chinese capital endured another day under an air quality “red alert” on Wednesday, with schools still closed, half of all cars kept off the roads and factories shut. But in other cities across northern China, tens of millions of people went about their daily routines in toxic air that was far worse than Beijing’s.

In Anyang, Henan Province, the air quality index read 999 at 3 p.m., three times worse than in Beijing and at the top of the scale. Handan, in Hebei Province, was not much better, at 822. And in the same province, the city of Shijiazhuang, a bit closer to Beijing, registered 460.

By United States standards, anything above 300 is “hazardous,” meaning people should stay indoors.

So while Beijing officials issued their first code-red alert, cities that are even more polluted enacted milder emergency plans, or none at all. There was no wholesale shutdown of coal-burning factories. Children continued to attend schools without air purifiers.

The patchwork policies pointed to a major shortcoming of efforts by Chinese officials to battle air pollution and protect residents from its effects.