SHANGHAI has been experiencing some of its most serious and long-lasting air pollution in months, as well as weather conditions that have contributed to thick clouds and a haze that has grounded some flights and led to vehicular crashes which killed at least one person and injured dozens.
Some expressways were closed from 3am to 9am yesterday because fog and haze created dangerous driving conditions, causing vehicles to line up for kilometers, according to the Shanghai highway authority.
Serious pollution that started on Saturday may continue today, though conditions may improve tomorrow, forecasters said.
The PM2.5 readings of tiny airborne particles smaller than 2.5 micrometers started to rise on Saturday afternoon and exceeded 300 micrograms per cubic meter yesterday morning, four times the standard for good air quality, which is 75 micrograms per cubic meter, according to the Shanghai Environmental Monitoring Center.
All 10 monitoring stations for PM2.5 across Shanghai turned on a purple light to indicate the second-highest level in the six-color alert system, meaning serious air pollution. That means those with some health conditions such as pulmonary problems may want to stay indoors when possible.
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