A rural household cooks using unprocessed biomass fuel in a kitchen without a chimney. The WHO Indoor Air Quality Guideline sets the 24-hour mean limit for PM2.5 in such settings at:

• A 10 µg/m³
• B 15 µg/m³ ✓
• C 25 µg/m³
• D 35 µg/m³

Explanation

The WHO Indoor Air Quality Guidelines for household fuel combustion set the recommended 24-hour mean PM2.5 interim target at 15 µg/m³ for clean technologies, though for unprocessed biomass in unventilated kitchens, actual concentrations far exceed this. The WHO global ambient air quality guideline for annual PM2.5 is 5 µg/m³ and 24-hour is 15 µg/m³. Option D matches India's NAAQS but not the stricter WHO indoor guideline.

Reference: WHO Indoor Air Quality Guidelines, 2021 ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.