Are we breathing ‘severely’ polluted air?

Aparna Banerji

Jalandhar, January 11

A 100-point difference has been recorded in the air quality index (AQI) readings in the machines of the Punjab Pollution Control Board (PPCB) and Jalandhar-based industrialist and philanthropist PC Sondhi’s Air Veda air quality trackers, raising questions over the level of air pollution in Jalandhar.

Clear air on ‘real’ data

Air Veda machines operate on laser technology and are accurate…the PPCB should clear the air on the real AQI in the city. — PC Sondhi, Industrialist

Machine accurate, authentic

The data collected by Civil Lines machine is accurate and authentic. We cannot take note of machines whose data is questionable as per NAAQS guidelines. — Sandeep Bahl, PPCB Engineer

Possible anomalies in the readings based on difference in air quality in higher traffic zones in the city cannot be ruled out. Since Jalandhar has only one government machine, the air quality in other higher traffic zones might considerably differ than the AQI at Civil Lines.

At any given point there is at least a 100-point difference in the two AQI trackers. Jalandhar’s air quality has constantly been “severe” as per the Air Veda trackers. However, the formal PPCB machine readings consistently record AQI at “moderate”. While the air quality reading on the Air Veda machine was at 403 at 4.24 pm today, which falls in the “severe” category, the air quality recorded in the PPCB machine was at 211, which is in the “poor” category.

While PPCB officials say they do not rely on air quality readings of low-cost sensor machines, independent experts say differing pollution levels as per areas call for recalibration of either of the machines. PPCB officials maintain their machines are authentic and costly, and installed as per the Central Pollution Control Board (CPCB) norms; they do not recognise any other machines with low-cost sensors. The Jalandhar Civil Lines PPCB machine – “Environment SA India Pvt Ltd”, costing over Rs 1 crore, was installed four years ago at the Civil Lines. It is the only government air quality tracking machine in Jalandhar. However, it needs constant recalibration.

On the other hand, the Sondhis have been tracking air quality through Air Veda air quality trackers, privately installed at their residence at the traffic-heavy area of Football Chowk in Jalandhar. They also formally broadcast the live AQI index recorded on their machine on an AQI bulletin board put at the roundabout.

Namita Gupta, founder Air Veda said: “We are formally working with the Gurugram Metropolitan Development Authority (GMDA) and IIT, Kanpur. Our Air Veda monitors are deployed at various places. At Air Veda, we calibrate our machines with CPCB machines. Since expensive government machines can’t be put up everywhere, that is where our lost-cost machines come in. We partner with the government to set up a hybrid network to record air quality data more democratically.”

Data varies a lot as per the area. One monitor for the city is insufficient. Sometimes 50-metre distance causes a vital difference. It’s quite possible that both the machines (in Jalandhar) are right (based on the area). Both machines also require constant calibration, she adds.

Varying readings

• On November 28, the Sondhis’ machine recorded an AQI of 318 (poor), while the PPCB’s recorded it at 120 (moderate) at the Civil Lines
• On December 22 afternoon, the Sondhi’s AQI board read 421 (severe or hazardous). PPCB’s AQI reading for Jalandhar on the same day was 151 (moderate)
• On January 2 morning, the Sondhis’ machine displayed AQI at 453 (severe) at Football Chowk; On CPCB’s website, ‘live air quality index’ was 189 (moderate)