Quick, proactive: Why Beijing’s Grap works, and Delhi’s doesn’t

NEWDELHI: Delhi’s deadly air pollution has exposed the lack of preparedness in NCR states to implement the Graded Response Action Plan (GRAP). It has also shown that many interventions under GRAP should have kicked in much earlier based on forecasts rather than when particulate matter concentrations were already peaking.

Beijing’s four-tier emergency response plan kicks in based on air quality index (AQI) forecasts and not actual recorded concentrations. For example, their blue alert is implemented when AQI is predicted to be greater than 200 for a day— dust-control measures are enhanced, public transit is preferred, outdoor activities in schools are reduced and vulnerable people are alerted about health impacts. Their red alert or the severe most category comes into force when the AQI is forecast to be more than 200 for four to five days—a routine in Delhi.

Based on such a forecast, offpeak work shifts are promoted, the odd-even scheme is enforced, a 30% traffic ban on government vehicles is enforced, only vehicles complying with latest auto standards are allowed, construction activity is stopped and power is not generated locally.

Under GRAP, severe+ or emergency measures kick in when PM 2.5 concentrations over 250 micrograms per cubic metres persist for 48 hours, the severe category is enforced when PM 2.5 concentrations are more than 250 micrograms per cubic metres or PM 10 concentrations are more than 430 micrograms per cubic metres.

The ministry of earth sciences has come up with an air quality