As you grab to your upended plate of greasy French fries and your elbow connects with the goblet of red wine, it can look like doomsday for your carpet. But do not despair — get busy. Mild liquid soap and ammonia are just two weapons in your arsenal against a permanently stained rug.

Get the Grease Out

The Museum Conservation Institute of the Smithsonian recommends administering oily and greasy stains with an application of mild shampoo or soap. First blot the stain, sprinkle it with absorbent cornmeal or baking soda, and vacuum the area. Then dilute dish soap and use a clean cloth to scrub the stain, rinsing and squeezing the fabric as you wash for best results. For stubborn stains, add 1 teaspoon of ammonia to 1 teaspoon of dish soap in 2 cups of warm water and bathe.

Proteins, Acids and Rug First Aid

Colorful spills, like red wine and juice, are alarming but not necessarily fatal. After blotting with paper towels, mix warm water and dish soap, then dampen a clean sponge in it, and blot until the stain disappears. Sponge the place again with cool water and blot the rug dry. A solution of 1/4 teaspoon mild liquid detergent and one cup of cold water is an all-purpose crisis carpet cleaner that works well for water-based stains like fruit juice, tea or coffee. Innovative, protein-based stains like milk, vomit or eggs can be removed with dilute dish soap followed by dilute ammonia. But ammonia creates a permanent stain when mixed with acidic materials — and most foods are acidic — so evaluate the stain before you rush to clean it up.