I can’t count the number of times that people have commented about the bleach they have stored for emergencies, but when you ask how old it is, it was bought so long ago they forget. But people don’t realize that yes, bleach needs to be replaced on a regular basis in your emergency supplies.
How regularly does it need to be replaced? At least once a year! Bleach loses its effectiveness over time and should be replaced regularly to ensure its potency.
Unopened bleach has a shelf life of about six months to one year. And once opened, bleach will start to degrade and lose its effectiveness over time. In general, it’s recommended to replace opened bleach every six months to one year, depending on storage conditions. If the bleach has been exposed to high temperatures or direct sunlight, it will degrade more quickly and may need to be replaced more frequently.
When storing bleach for emergency use, it’s important to keep it in a cool, dry, and dark place. Exposure to heat, light, and air can cause the bleach to degrade more quickly. It’s also a good idea to label the container with the date that the bleach was opened, so you can keep track of how long it has been in storage.
In summary, to ensure that bleach remains effective for emergency use, it should be replaced every six months to one year, depending on storage conditions. Additionally, proper storage can help extend the shelf life of bleach and ensure its potency when it’s needed.
That said, if a real emergency does occur and you use your current stores of bleach, you can use “expired” bleach rather than nothing at all, but as the potency has degraded, you will need more of it. Since bleach isn’t usually an item food banks accept, you can move the expired bleach to the back of your emergency stockpile and make sure it is clearly marked as expired. But of there is a societal breakdown and you cannot purchase new bleach, having old bleach on hand will be useful as it is better than nothing at all. But again, remember its potency will be degraded the older it is so the general rule of thumb on amount of bleach needed for different tasks will need to be greatly increased and it still might not work as well as bleach under a year old.
Lastly, don’t forget you want regular bleach, not any of the other varieties of bleach such as lemon scent which is popular for cleaning or meadow fresh which is popular for laundry and cleaning. While these might smell great for cleaning, they aren’t what you want for disinfecting water, for example.