An improvement in Beijing’s air quality last year compared with 2014 may have had more to do with weather patterns than with a decline in emissions, environmental experts say.
The Municipal Environmental Protection Bureau said the average concentration of PM2.5 particles — used as a proxy for measuring air quality — at 81 microgrammes per cubic metre, was down
6 per cent from 2014’s average of nearly 86 microgrammes and 10 per cent from 90 in 2013. The World Health Organisation’s standard for safe air is an annual mean of 10 microgrammes.
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