Delhi AQI: Are air purifiers effective when air quality slips into ‘severe’ category? Doctors answer

North India, particularly Delhi-NCR, has been witnessing deteriorating air quality for the past few weeks, with air quality index (AQI) readings touching the "severe" mark in many areas. This has attracted sharp criticism from citizens and alarming advisories from the health officials. Many have taken to social media to report that the pollution is causing breathing difficulties and eye irritation.

The public concern has also sent sales of air purifiers surging, with e-commerce platforms like Amazon India stating that they have risen by over five times.

However, with air quality worsening, are air purifiers really beneficial for the users? Livemint spoke with several doctors to decode this.

Dr Shaleen Bhatnagar, HOD - Critical Care, Pulmonologist at Dehradun's Kailash Hospital, said that air purifiers equipped with high-efficiency particulate air (HEPA) filters and activated carbon layers are capable of removing fine particulate matter like PM2.5, allergens, and certain toxic gases, thereby reducing the burden of pollutants that exacerbate respiratory and cardiovascular symptoms.

"However, their effectiveness is limited to the closed space in which they operate. They cannot replace the need for clean outdoor air or address the root cause of pollution," he added.

“When the AQI gets too bad, their effectiveness is doubtful as indoor air itself is too unhealthy to be purified by the purifier,” said Dr Harish Chafle, Senior Consultant, Chest Physician, Bronchoscopist, Intensivist and Sleep Disorders specialist, at Mumbai's Gleneagles Hospitals.

According to Dr Akshay Mehta, Senior Consultant- Neonatology & Paediatrics at Motherhood Hospitals, Noida Extension, pollution poses a major health concern for mothers and young children.

“For children, their lungs are still developing, and they breathe nearly twice as fast as adults, which means they inhale more polluted air per minute. In such conditions, air purifiers can make a noticeable difference, particularly in protecting infants, toddlers and expectant mothers who spend most of their time indoors,” he said.

"For optimal performance, keep it running 24/7, though you can use a lower setting during the day and run it on a high setting when needed. Keeping doors and windows closed is essential for the device to work effectively," said Dr Chafle.

Doctors also suggested that going out should be avoided as much as possible during the period of high pollution.

"Ensuring proper ventilation in kitchens and bathrooms through exhaust fans helps eliminate smoke and moisture that promote microbial growth. Avoiding the burning of incense sticks, candles, or mosquito coils can further minimise indoor particulate matter," he said.

Dr Sushil Kr Upadhyay, Consultant Pulmonologist, Kailash Deepak Hospital, added, "Keeping windows closed during high pollution hours, cleaning floors and furniture with a damp cloth instead of dry dusting, and avoiding smoking or incense burning inside the house all help maintain better indoor air."