At The Ready Store, we often get this question. Many believe that you can use household bleach to purify water storage. Here is the best answer we can provide. Household bleach is not manufactured with human consumption in mind. The chemicals are much higher than what would be considered safe for human consumption. Having said that, if you don't have anything else, using bleach may be better than nothing.
It's not recommended to use straight bleach to purify your stored water if you have better options. It would be much better to purchase a water treatment that is guaranteed not to harm you when consuming. The water treatment we and many other companies carry would purify the stored water up to 5 years so you don't need to worry about changing it out or over contaminating the water with bleach.
One option is sodium hypochlorite (bleach) but has been manufactured so that there are no impurities in it and as a result it is the only bleach product that has been approved and certified by the EPA for human consumption.
Many people use unscented household bleach to store there water. We don't recommend it because it can potentially be dangerous if you don't know what you're doing. Why not use a bleach that's been certified for consumption just in case?
If you do choose to use household bleach to fill your water storage containers, please follow these steps put out by the Center for Disease Control:
1. Wash the storage container with dishwashing soap and water and rinse completely with clean water.
2. Sanitize the container by adding a solution made by mixing 1 teaspoon of unscented liquid household chlorine bleach in one quart of water.
3. Cover the container and shake it well so that the sanitizing bleach solution touches all inside surfaces of the container.
4. Wait at least 30 seconds and then pour the sanitizing solution out of the container.
5. Let the empty sanitized container air-dry before use OR rinse the empty container with clean, safe water that already is available.
The CDC only recommends using unscented common household bleach for cleaning water supplies if you don't have bottled water or boiling is impractical. They also only recommend using it in small quantities.
Check the label to see what the percentage make up of Sodium Hypochlorite is in the bottle. Here is a chart of how much bleach to add per bleach grade: