On the lines of Delhi, Maharashtra CM Eknath Shinde on Thursday directed BMC to install air purifiers in the city. This comes in the wake of the city recording poor air quality for the past several days. On Thursday, Mumbai's overall air quality index was 273, according to the System of Air Quality Weather Forecasting and Research (Safar) which falls in the 'poor' category. Also, BMC has been told to increase urban forestry in the city.