The National Ambient Air Quality Standards (NAAQS) in India set the 24-hour average PM2.5 standard at:

• A 60 µg/m³ ✓
• B 25 µg/m³
• C 100 µg/m³
• D 150 µg/m³

Explanation

The Central Pollution Control Board (CPCB) NAAQS (2009 revision) sets the 24-hour average PM2.5 standard at 60 µg/m³ for India. The WHO Air Quality Guidelines (2021 update) recommend 15 µg/m³ for 24-hour mean, which is considerably stricter. The annual mean standard under NAAQS is 40 µg/m³. PM2.5 (particles <2.5 µm) penetrate the alveoli and are associated with cardiovascular and respiratory mortality; they are the most health-relevant pollutant in Indian urban settings.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.