Days after Diwali, 24 DPCC monitors go dark for eight hours

As Delhi grappled with its latest pollution crisis on Tuesday morning and failed to shed the after-effects of the unchecked use of firecrackers on Diwali day, a fresh problem impaired the Capital’s pollution response — 24 of the city’s 35 air quality monitors run by the Delhi Pollution Control Committee (DPCC) went dark and stopped throwing up data. As a result, Delhi’s 24-hour average air quality index (AQI) trended much lower than it actually was throughout the day, catching residents and experts off-guard.

- Jasjeev Gandhiok

DPCC attributed the glitch to a server error, adding that the problem did not impair data collection. The glitch, which began at 7am, was rectified by 3pm and the Central Pollution Control Board’s (CPCB) 4pm AQI bulletin took into account data from all active stations throughout a 24-hour period, said the agency.

Still, experts said the blackout underlined the importance of accurately measuring pollution levels, especially when the city was neck-deep in yet another air emergency two days after Diwali.