A 2.25 inch by 2.25 inch black and gold tin box of tablets used to contain Halazone. Halazone has been widely used to disinfect drinking water.

Halazone tablets have been used to disinfect water for drinking, especially where treated tap water is not available. A typical dosage is 4 mg/L.

Halazone tablets were commonly used during World War II by soldiers for portable water purification, even being included in accessory packs until 1945.

Halazone has largely been replaced in that use by sodium dichloroisocyanurate. The primary limitation of halazone tablets was the very short usable life of opened bottles, typically three days or less, unlike iodine-based tablets which have a usable open bottle life of three months.