Pour 3/4 cup of white distilled vinegar into a bucket. Add 1/2 cup laundry detergent and 1 gallon of warm water. Stir the solution until mixed well.
Submerge the coal-stained work clothes in the vinegar and detergent solution. Rub the solution into the coal stains. Allow the clothing to soak for 30 minutes in your homemade prewash solution.
Remove the clothes from the solution and rinse them with warm water.
Launder your work clothes in warm water with laundry detergent and oxygen bleach.
Check the clothing for any remaining coal stains before drying them. If any coal stains are present, treat the stains by sponging them with rubbing alcohol. As the coal stains are lifted, rinse the sponge, apply more rubbing alcohol and continue to blot the stains.
Wash your work clothes again. Line dry your work clothes or place them in the dryer, as instructed on the care label.