In December , Beijing issued itsvery first“red alert ” over the level of smogginess wrap the urban center . The pollution reached such a point that officials took the decision to come together many factories , keep children indoors , and limit the number of railway car on the road . But to many it arrive as a surprisal , as the level of pollution had been much high in the past , leading some to assume that it was a house of the government taking more business concern over the health of its the great unwashed and the environment .
Yet now the Taiwanese state news way Xinhua has report that the city is toraise the thresholdfor issuing red alerts , which are the highest air defilement word of advice . Many countries use the air quality index ( AQI ) as a measure of how much pollution is in the melody . This looks at the compactness of self-coloured and liquified particles larger than 2.5 micrometers , known as particulates , in the air , as well as other harmful nub such as ozone , carbon monoxide and sulfur dioxide . How land measure the AQI varies from land to commonwealth .
The calculation of the AQI by Chinese authorization combines the measurement taken from all of these pollutants to give a recitation from zero to more than 500 . Back in December , a indication of over 200 for three days directly that prompted the ruby alert . But now it will have to hit 200 for four days , be at over 300 for two sidereal day , or offend an AQI of 500 for one day before the metropolis will issue an alert .
To some , this is an attempt by the government to limit the economical impact of issuing red alerts by reducing them , as they leave in people being unable to go to work and limits on the number of cars on the road being put into plaza . “ There will be multiple time of red alerts in a year if we continue using the current standards , which will bring about a high societal and economic cost , ” Ma Jun , an environmental researcher in Beijing , toldThe New York Times .
During the last red alarum , the metropolis recorded the peak number of particulates in the air as 291 microgram per cubic cadence . The World Health Organization recommends that the level of these particulates should be determine to a 24 - hour norm of just 25 micrograms per cubic measure . So the fact that the Beijing has just made it harder for a red alert to be raised could be seen as worrying .
The new guidelines will not , however , only be in place for Beijing . They will also cover the surrounding industrial areas , including the major porthole city of Tianjin , which has a massive and rapidly extend manufacturing diligence . It is hoped , Xinhua claims , that these unexampled normal might actually work to decoct the air travel befoulment pumped out by the wall regions , which could have a positive whang - on effect for the city itself .
principal image credit : LWYang / Flickr CC BY 2.0
