They're probably something you're not washing every day, but when you do launder oily rags, never put them in the dryer. If you've cleaned up a spill of cooking oil or have oily work rags from the garage, washing them won't always get all the oil out of the fabric. And if you toss them into the dryer, the high heat has the potential to create a fire from the residual oil. The best solution is to hand-wash and air dry. If the rags are beyond saving, toss them into the trash.
ANDREWS MCMEEL SYNDICATION