Does Hot Water Make Bleach Ineffective?

Put on protective gear when diluting or using bleach as it irritates mucous membranes, the skin and the airway. Cold water should be used for dilution as hot water decomposes the active ingredient of bleach and renders it ineffective.

Does heat affect bleach?

Not only does bleach retain its effectiveness in warm or hot water—it will help it work faster and better as a disinfectant and stain-remover, too.

At what temperature does bleach become ineffective?

The bleach active in Clorox® Regular Bleach₂ is sodium hypochlorite, and it does not “deactivate” in water above 77°F. However, a higher water temperature does increase the rate that the bleach degrades into salt and water. This break down is natural, and is part of what makes bleach so environmentally friendly.