Rust stains on laundry can occasionally occur for a number of reasons including direct contact, rust spots on the washer drum, etc. They can also occur if particles are stirred up in the water supply mains as a result of flushing, construction activity, main breaks or fire events.
The best approach to rust stain treatment is prevention…if you see that the water is cloudy/rusty – call the water company and postpone doing laundry until the condition is corrected. However, if the stains do occur, try the following approach, recommended by Ohio State University, to effectively treat the yellow-orange-brown stains that can result from iron in water.
DO NOT USE BLEACH..…and do not dry stained items in the dryer…..both will serve to “set” the stain and make it harder, if not impossible, to remove.
Relaunder the article using a commercial rust remover (such as Iron Out®, RoVer®, Rit Rust Remover®, Miracle-Rid-Iron® or Whink®). The key ingredient in these compounds is often an acid, normally oxalic or hydrofluoric acid, which puts the iron back in solution and dissolves the stain. Handle with care and avoid skin / eye contact / ingestion. Follow the label directions and work with good ventilation.
After the stains have been treated as above, re-launder with a good detergent and rinse thoroughly.
More information can be found on the Ohio State website at:
Lastly, if you have inadvertently drawn dirty/rusty water into your hot water heater, you may want to flush out the heater after the event to remove any sediment. This procedure should be done every so often to maintain the efficiency of the water heater regardless, using the drain valve at the bottom of the heater. If you are unsure of how do perform this procedure safely, you should contact your plumber or handyperson, as the water that comes out will be hot and under pressure.