Keeping Indoor Dust Down Through Delhi's Bad-Air Months

1. Seal the gaps — the cheapest thing on this list

Most of the dust entering a closed Delhi flat comes through a small number of predictable gaps, and most of them cost very little to close.

• Under the main door. The single biggest one. A brush strip or door sweep is inexpensive and makes a visible difference within days.
• Window frames. Old sliding windows in particular. Self-adhesive foam or rubber sealing tape along the frame is a twenty-minute job.
• The AC core hole. The gap where copper pipes pass through the wall is very often left half-sealed. It should be filled properly — and it is a route for pests as well as dust.
• Exhaust fan openings when not in use, and the bathroom vent.

2. Stop moving dust around and start removing it

Dry dusting with a cloth mostly lifts fine dust into the air, where it settles again an hour later. It feels productive and achieves very little.

• Damp microfibre, not dry cotton. Damp traps and removes; dry redistributes.
• Vacuum before you mop, not after. Mopping over grit turns it into a slurry that dries as a film — and on marble, it grinds.
• Top down. Fan blades and cupboard tops first, floors last, or you clean the floor twice.
• Wash curtains and soft furnishings more often in season. They hold more dust than any surface in the room and release it every time someone brushes past.
• Doormats at every external door, and shoes off inside. This is unglamorous and it works better than anything else here.

Our deep cleaning guide covers what a professional clean reaches that routine cleaning does not.

3. Anything with a filter needs it changed more often here

Delhi shortens every filter interval printed on every manual. Treat the manual as an optimistic minimum.

• AC filters — rinse fortnightly in the season. Our summer AC care tips cover the routine.
• Air purifier filters — they clog faster in Delhi than the rated life suggests. A purifier running on an exhausted filter is a fan.
• Vacuum cleaner filters and bags — a choked vacuum blows fine dust straight back out.
• Chimney filters — kitchen grease plus airborne dust is a worse combination than either alone. See our chimney care tips.

4. Ventilate at the right time of day

A closed flat still needs air changed, particularly a small one where people cook and dry clothes indoors. The question is when.

• Outdoor particulate levels in Delhi are typically at their worst in the early morning and late evening during winter, and better through the middle of the day.
• If you are going to open windows, midday to mid-afternoon is generally the less bad window.
• Always ventilate while cooking and after a hot shower, regardless — trapped moisture causes its own problems, and a bathroom with no airflow is how damp and mould start.
• Check an AQI app rather than guessing. It costs nothing and the daily variation is large.

5. Book the deep clean at the right end of the season

Most Delhi households deep clean before Diwali, which is sensible for the festival and slightly badly timed for the dust. The worst air usually arrives just after.

If you only do one professional clean a year, consider doing it in February or March instead — after the worst of the winter air has passed and before summer. You get the benefit for longer. If you do two, keep the festive one and add the spring one; our pre-Diwali cleaning tips cover the first.