Bleach is typically only good for 24 hours after mixing with water.
Why Bleach Loses Effectiveness After Mixing
The active ingredient in bleach, sodium hypochlorite, degrades over time, especially when diluted. This degradation is accelerated when bleach is mixed with water due to several factors:
- Light Exposure: Light can break down sodium hypochlorite.
- Heat: Higher temperatures speed up the decomposition process.
- Contamination: Even small amounts of contaminants can react with the bleach, reducing its strength.
- Air Exposure: Oxygen in the air also contributes to the degradation.
Best Practices for Using Bleach
To ensure you're using bleach at its optimal strength, follow these guidelines:
- Mix Fresh Daily: Prepare a new bleach solution each day you intend to use it. Avoid storing diluted bleach for extended periods.
- Use Cold Water: Mix bleach with cold water to slow down the degradation process.
- Store Undiluted Bleach Properly: Keep undiluted bleach in a cool, dark place, away from direct sunlight and heat sources. The expiration date on the bottle refers to the undiluted product.
- Measure Accurately: Follow the recommended dilution ratios for your specific cleaning task. Too much water weakens the solution unnecessarily.
- Use Immediately: For the best disinfection, use the freshly mixed bleach solution immediately after preparation.
Alternatives
If you need a longer-lasting disinfectant solution, consider alternatives like:
- Commercial Disinfectant Wipes: These wipes are pre-moistened with disinfectant and have a longer shelf life than diluted bleach.
- Other Disinfectant Sprays: Look for disinfectant sprays that are EPA-registered and suitable for your intended use. Always follow the manufacturer's instructions.
By understanding how bleach degrades after mixing and following the recommended guidelines, you can ensure you're effectively disinfecting surfaces and protecting yourself from harmful bacteria and viruses.
