LAHORE: An orientation session was organised by the Punjab Environment Protection Department (EPD) for journalists where they were shown how the Air Quality Monitoring stations’ worked and the Air Quality Index (AQI) measurements were taken.

The meeting held at the EPD head office on Wednesday was presided over by Deputy Director of Laboratories Shaukat Hayat.

Hayat gave a detailed presentation regarding the AQI measurement and briefed the media persons on how the AQI data was being collected.

Independent experts back these devices

“Every country has its own AQI, based on different national air quality standards,” he said. However, he added that different countries rather than basing the standards on their ‘exclusive concern for human health’, based them on the lowest achievable emission rate.

“The AQI by EPD is being monitored on a 24-hour average basis under the international recommendations, because data based on the past 24 hours is more reliable than that based

on two hours or hourly average. AQI can increase due to an increase in air emissions (traffic) during peak hours and also due to stagnant air often caused by temperature inversion or low wind speed due to which air pollutants remain hovering in the area leading to a high concentration during that particular time and space.”

He added that most measurements available on some websites show hourly readings which is contrary to the EPD’s 24-hour collective data collection procedure.

Hayat also talked about private air monitoring devices, which the EPD calls ‘inaccurate and misleading’. EPD officials said since these air monitors even detect steam as particulate matter (PM) their reports were considered incorrect.

He also gave a demonstration of an Air Visual device where steam was blown in front of the device and it showed a high value of pollution, taking steam as a pollutant, while ignoring humidity and moisture as factors. The officials said that EPD’s own recommended analyzers showed the results irrespective of humidity influence. EPD Spokesperson Sajid Bashir added that most of the private devices were not calibrated properly while they are also very cheap. He said one of these devices were recovered in a recent raid conducted by the EPD staff in a factory in Sundar Area.

“During the previous smog span, it was clarified in various smog policy meetings that we cannot measure our air quality according to other countries’ EPA standards,” he said. “Every country has different geographical and climatic conditions so if a device is working in Europe, it will not function in Pakistan.”

DETRACTION

Earlier, experts while speaking to Dawn had dispelled the idea that the monitors by Air Visual were giving false information, saying the instruments were remotely calibrated via cloud and that if one was not properly calibrated or was giving wrong readings it disappeared off the network.

They were of the view that the low-cost devices gave a rough estimate and that these readings were recognised world over by the United Nations.

They also said that these devices could not be compared with the heavy machinery which the EPD was using on its six stations for more precise readings. They said readings were not uploaded on an hourly basis, rathertheir website data was based on the last 24 hours which was of little use.

Jeffery K Smith, an environmental health expert and consultant says there is a great potential for the low-cost sensors to increase the public awareness about air pollutants.

“The public can be aware of the local (and hyper-local) levels of air and environmental pollution,” he told Dawn.

“By local, I mean they will begin to associate street names and neighbourhoods as hot spots of toxic gases (cytotoxins and neurotoxins like oxides of the Nitrogen and Ozone) that are more or less omnipresent on the streets on which they commute daily.”

He said the citizens were using low-cost monitors to help create maps that reveal these pollution hot spots within their city.

“This kind of ‘participatory urbanism’ should be leveraged by the regional air quality monitoring regulators as extra detection capacity, citizens can provide real-time detection of potential hot spots to city managers who then respond to these alerts, validate the air pollution source and take action to ensure the polluter stops the illegal activity,” he said.

“These actions and the awareness generated will lead to a sustainable change of policy, habits and lifestyle.”

Published in Dawn, November 12th, 2020