A room with three smokers is more dangerous to human health than the air on even Beijing’s most polluted days, according to the World Health Organization.
Bernhard Schwartländer, the WHO’s China representative, told an audience in China on Wednesday that three smokers can push the level of PM2.5—the smallest, most dangerous air pollution particles—to 600 micrograms per cubic meter. That compares with a PM2.5 level of around 500 on a day of heavy pollution in Beijing.
Add in a few more smokers, and the air becomes worse than any level experienced outdoors in Beijing, or in any of the world’s most-polluted cities:
That poses something of an issue for residents of China, home to around 300 million smokers, where smoking indoors is largely accepted. Even in police stations, it is not uncommon to find officers lighting up while taking notes from a victim of crime.
City governments are nevertheless beginning to introduce anti-smoking laws; in June, Beijing will ban smoking in all indoor public places and offices. The Chinese government has tried and failed before to enforce a smoking ban. But this time it has special hand signals.