A wet or damp sleeping bag is a breeding ground for mould. Even storing it in a cool damp place can cause mould growth. You don't have to throw the sleeping bag away just because there is mould growing on it. The cleaning process may take a few days to complete because a simple washing won't get rid of the mould spores.
Mix 1/2 cup of Lysol with 1 gallon of hot water in either a deep sink or bathtub. You may need to use a measuring cup to get the exact measurements.
Soak the sleeping bag in the Lysol solution for about an hour. Make sure the affected area is completely submerged in the Lysol mixture. This will help kill the mould and prevent it from growing.
Drain the sink or bathtub of the Lysol mixture. Leave the sleeping bag in bathtub or sink.
Mix 1 gallon of hot water with 1 cup of lemon juice and 1 cup of salt in a large pail. This mixture will help get rid of the mould smell.
Pour the water, lemon and salt mixture over sleeping bag in the sink or bathtub.
Squeeze any excess liquid from the sleeping bag.
Dry the sleeping bag completely, either outside in direct sunlight or in a warm place. It may take a day or two for the sleeping bag to dry completely.
Repeat the same steps again to thoroughly kill all the mould spores.
Dry the sleeping bag completely.
It's recommended that you wash your sleeping bag after treating the mould spots. See your instructions manual or the label on the bag for washing instructions.
Do not use any bleach on your sleeping bag. This may damage the fabric and ruin the bag as a result.