Saltpeter appears as a white, powdery substance on walls, often due to moisture seeping through masonry. Mildew appears as dark spots or patches caused by dampness. Both can damage surfaces and affect indoor air quality, so it’s best to tackle them promptly.

Step 1: Protect Yourself and the Area

Wear gloves, a mask, and protective eyewear.

Remove furniture or cover it with plastic sheets.

Ventilate the room by opening windows and doors.

Step 2: Remove Saltpeter