At 122, harmful AQI days in 2024 six more than last year

The number of days with harmful air quality has risen this year, surpassing figures from the previous years.

  From January 1 to November 18, there were 122 days when the air quality index (AQI) exceeded 201, compared to 116 days during the same period in 2023.

  In contrast, the number of days when the AQI ranged between 0 and 200 stood at 201 this year, slightly lower than 206 days recorded last year.

  According to the Central Pollution Control Board (CPCB), AQI levels between 0 and 200 are divided into three categories — good (0–50), satisfactory (51–100), and moderate (101–200).

 

  While these levels are less harmful, their health impacts vary, ranging from minimal discomfort for sensitive individuals to moderate breathing difficulties for people with lungs, asthma, or heart conditions.

  However, air quality in the poor (201–300), very poor (301–400), and severe (above 400) categories pose a significant threat to health. 

  Poor air quality leads to breathing discomfort for most individuals during prolonged exposure, while very poor conditions can cause respiratory illnesses.

  Severe levels not only affect healthy people but also severely impact those with pre-existing health issues.

  The rising number of days with harmful AQI levels highlights the growing challenge of controlling air pollution.

  India now leads the world in the number of cities listed among the top 100 most polluted globally, surpassing China by a significant margin.

  According to a recent S&P Global Mobility web presentation, 39 Indian cities feature in the list, compared to 30 cities in China, its closest competitor.

  According to data from the CPCB, Delhi remains one of the most polluted cities in India. On November 18, the city recorded an average AQI of 494, the highest in the country.

  Most monitoring stations in Delhi reported an AQI of 500, the upper limit of India's AQI scale.

  However, the international air quality monitoring app IQAir recorded Delhi's AQI at a staggering 1,600 on the same day.

  The discrepancy arises from differing standards for measuring air quality across countries.

  In India, the permissible limit for PM2.5 concentration is 60 micrograms per cubic metre.

  Countries adhering to World Health Organization (WHO) guidelines have much stricter limits of five or 10 micrograms per cubic metre.

  Additionally, India’s AQI scale is capped at 500, which serves as a critical threshold indicating severe pollution levels.

An AQI beyond this cap signals hazardous conditions and highlights the urgency of addressing the capital’s worsening air quality.