When AQI exceeds 300, toxic PM2.5 poses serious health risks by penetrating lungs and bloodstream. Experts advise using certified N95/N99 respirators, avoiding high-intensity outdoor activity, and keeping windows sealed. Run true HEPA air purifiers indoors, check local AQI updates, stay hydrated, consume antioxidant-rich foods, and practice steam inhalation and saltwater gargles to reduce respiratory irritation.
