Products you must never mix

Chlorine bleach and ammonia (found in some glass and multi-surface cleaners) — produces chloramine gas.

Chlorine bleach and acids such as vinegar or limescale remover — produces chlorine gas.

Hydrogen peroxide and vinegar in a sealed container — produces peracetic acid.

If one treatment fails, rinse the fabric thoroughly and let it dry before trying another. Layering removers is the most common way people damage an item they could have saved.