Soaking used pads in cold water prior to washing in warm water, is to ensure the pads remain stain free. Blood is washed out easily when initially rinsed in cold water. After that you can wash the pad in warm water. However, harmful bacteria can develop when the pads stay moist. It is not so much the washing but the drying of your clean pads that matters! Dry your pad in a tumble dryer or in direct sunlight (best as UV kills germs) and you’ll be sure that it is safe to use!