Hadex Dosing

After the prescribed working time, drinking water treated with Hadex® is ready for drinking. Hadex® can be added to your drinking water supply manually or by automatic dosing for large flows with either a dosing unit or inline measuring equipment. Three standard dosages are given for drinking water treatment of large capacities (from approx. 50m3) , for smaller quantities when you are camping or with outdoor sports another dosing concentrations are given.

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  • Normal dosage

    (Large quantities)

  • Working

    The normal Hadex® dosage should reduce and prevent growth of bacteria, algae and other micro-organisms. The water to be treated should be clear and of normal quality, meeting the usual public health requirements. This dosage meets the standards laid down by the DSI/DOT/NMD and other maritime authorities.

  • Rule

    Hadex® should be added regularly to the water. As a rule, it should be added during each bunkering, dependent on the amount of fresh water being bunkered, or every 2 weeks (in areas with a warm climate), up to a maximum of every 4 weeks.

  • Dosing

    A normal Hadex® dosage is only 1 litre Hadex®: 50 m3 (50,000 litres) of drinking water.

Hadex concentration

Hadex® contains < 50,000 mg (< 50 gm/dm3) active chlorine per litre of product. This results in a theoretical concentration of ± 1 mg/litre total chlorine after addition of 1 litre: 50 m3. However, in practice, the free chlorine measurement after dosing will come out at ± 0,5 mg/litre (ppm), dependent on the water quality (organic matter, pH, etc.). An accurate testing kit, complete with instructions, is available.

  • Extra dosage

    (Large quantities)

  • When to apply?

    Use the extra Hadex® dosage whenever water is of inferior or questionable quality. It can also be applied when the water contains an abnormal amount of floating particulate and filtration is not possible.

  • Prevention

    The presence of particulate can promote bacteria growth; Hadex® drinking water disinfectant helps to prevent this.

  • Dosing

    The extra Hadex® dosage is 1 litre Hadex®: 25 m3 (25,000 litres) of drinking water.

  • High dosage

    (Shock treatment, large quantities)

  • Application

    This should be applied when treating drinking water under epidemic conditions and/or when the water is suspected of being infected.

  • After repairs or renewals

    The high dosage should also be used as an initial treatment for the disinfection of tanks and pipelines after repairs or renewals. For details of this treatment, please read the following instructions.

  • Dosing

    The high dosage is 1 litre Hadex® : 5 m3 (5,000 litres) of drinking water.

Procedure after repairs or renewals

Before the drinking water in a repaired or renewed system is potable, the whole system should be cleaned thoroughly. The coating of an existing tank should be inspected and, when necessary, repaired or renewed. Allow for sufficient drying out time. Visible contamination should be removed from the tank, after which the tank should be flushed with drinking water, which should subsequently be discharged.

The tank may then be filled with water treated with Hadex® high dosage (1 litre Hadex : 5 m3 drinking water) until the tank starts overflowing. When necessary, 30 minutes after Hadex® dosing leave all drinking water taps open for 15 minutes to ensure that the pipework system has been flushed clean. After allowing the water to stand in the tank for a minimum of 6 hours, this should be pumped out for disposal; the tank may not be entered after this. The tank may then be filled with fresh drinking water and the normal Hadex® dosage should be added (1 litre : 50 m3). We recommend a water analysis to be carried out to check the water quality.

Procedure high-risk situations

In case people have gastric or intestinal complaints you should follow the high dosing procedure. For additional advice, consult a medical expert or your Hadex supplier. We recommend a water analysis to be carried out to check the water quality on a regular base. Once water tests indicate the water has been polluted, you should follow the high dosing procedure as well. Polluted water is more likely to occur in high-risk, tropical areas, but a water management plan will give you insight in the water quality.

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