A 12% solution is widely used in waterworks for the chlorination of water and a 15% solution is more commonly used for disinfection of waste water in treatment plants. High-test hypochlorite (HTH) is sold for chlorination of swimming pools and contains approximately 30% calcium hypochlorite. The crystalline salt is also sold for the same use; this salt usually contains less than 50% of calcium hypochlorite. However, the level of active chlorine may be much higher.

Spraying - Following rough washing to a good Water White or better, apply dilute Bleach to 1 - 3% strength. First wet the tank surface (spray with DI water), then spray all over with Bleach, wait 30 minute (but do not allow to dry) and then rinse very well with DI water, including the tank top towards the sump. To ensure that you have covered all areas properly, this process should be carried out at least twice with good DI water. Injection -no. HANDLING AND STORAGE PRECAUTIONS: Do not store adjacent to chemicals that may react if spillage occurs. When shipped. If closed containers become heated, vent to release decomposition products (mainly oxygen under normal decomposition). Do not mix or contaminate with ammonia, hydrocarbons, acids, alcohol or ethers. Re-circulation - Following rough washing to a good Water White standard or better, apply dilute Bleach to 1-3% strength. Mix sufficient Bleach with fresh water in the tank and heat this mixture to 40 - 50 degree C, circulate through the drop line if fitted and than circulate through butterworth machine for 3 hours. After re-circulation immediately warm butterworth to (500 C) the tank for 3 hours at maximum pressure, increase the water temperature to 80-850 C after 45 minutes. Check (by smell) that there is no Bleach remaining, then fresh water rinse and dry. ** When there are a number of tanks requiring re-circulation, it may be significantly more efficient to make up a large batch or number of batches that can be transferred on between tanks as required