"Phoraid" Disinfectant
Water Treatment Study – March 2003. Carried out by William Keane B.Sc., Manufacturing Chemist for Phoraid International, U.K.
Because iodine retains its activity over a wider range of pH values than chlorine, it has been advocated for the sterilisation of drinking water, especially under emergency conditions, and for the treatment of swimming pool water. Change & Moms (1953) recommended a concentration of 8 parts per million, chosen because at such a level it is lethal to most water-borne pathoganie organisms, including amoebae and virus in about 10 minutes at normal temperatures, or rather longer at lower temperatures. Later Change (1958) put the level at 4 parts per million with a contact time 15-20 minutes. These concentrations appear to be high in comparison with the findings of Chambers et a!. (1952), but it must be borne in mind that the treatment was intended for waters of unknown and doubtful quality (Moms et a!. 1953. Chambers assessed the minimum concentrations lethal in 1 minute against range of organisms of intertinal origin and found that whereas 4.5 parts per million in cold water at pH 9.1, 0.6 part was adequate at pH 6.5 and in the ambient temperature range of 20—26deg.
Alkaligenes faecalis is said to be the most difficult of bacteria to deal with in swimming pools, being about six times more resistant than the coliforms, salmonellae and shingellae (Marshall, Wolford and Faber, 1961).
More recently in 1966 it was determined that using a more stable complexed iodophore — (Phoraid 5000WT) – 5WT 5% Av 12 plus 5% citric acid it was highly effective at the following dilutions:
25 Parts per million effective in 4 minutes contact time (99.999%)
10 Parts per million effective in 60 minutes
5 Parts per million effective in 24 hours
Large volumes 0.5 ppm pH 5 to 6
"PHORAID" is effective against many or all water borne bacteria, fungi, algae and can be used to treat water for chickens, animals, and human consumption. It controls spore forming bacteria and the more resistant coliforms.
Including:
CHART FOR CALCULATING DOSAGE
"Phoraid" 5 WT has been specially formulated for water treatment combining the biological properties of "Phoraid" with the sequestering action and pH control of citric acid. Even at 1,000 – 10,000 dilutions
|
"Phoraid" 5WT |
|
 |
Water |
|
|
ppm |
|
Ph |
|
|
|
1 part |
to |
|
200 parts |
|
= |
25 |
|
4/5 |
|
(Effective in 4 minutes) |
|
1 part |
to |
|
500 parts |
|
= |
10 |
|
6 |
|
(Effective in 60 minutes) |
|
1 part |
to |
|
1,000 parts |
|
= |
5 |
|
6 |
|
Emergency Drinking Water |
|
1 part |
to |
|
10,000 parts |
|
= |
0.5 |
|
6/7 |
|
Large Volumes |
To be dispensed with 100ml - 5ml calibrated two cap bottle.
