BS/EN 16713-3-2016 pdf download.Domestic swimming pools Water systems Part 3 : Water treatment – Requirements.
In order for a disinfectant to work safely and reliably, it shall be equally effective against viruses, bacteria, fungi and parasites. Indications for the microbiological parameters providing effective disinfection of the pool water is in Annex B. When choosing a disinfectant, differing advantages and disadvantages as regards handling, storage, transport. influence on pH value. etc. shall be taken into account. The safe, simple and economic operation should be at the forefront of that choice.
In addition, the disinfectant should react very quickly, have a long-lasting effect (residual effect), as well as be easily and quickly measurable. Taking all of these requirements into consideration, the recommended reliable and suitable disinfectant is chlorine or bromine. The chlorine may be supplied in a gaseous, liquid (made onsite or delivered ready-made) or solid form.
In order to minimize and reduce disinfectant by-products, special attention should be paid to an effective filtration (see EN 16713-2).
The disinfection of the pool water may require the installation of disinfection equipment. The disinfectant shall be added to the filtrate either using dosing pumps, erosion/soaker feeders, in situ electrochlorination systems, control valves, or other suitable methods. An automatically controlled feeder unit and equipment for determining and recording parameters such as free chlorine, the Redox potential and pH value may also be installed.
NOTE The automatic system may need periodic checks according to the manufacturer’s instructions.
Chlorine tablets and chlorine floating dispensers shall be used according to manufacturer’s Instructions. 4.5.2 Primary disinfectants
Chlorination is the most widely used pool water disinfection method, usually in the form of chlorine gas, sodium or calcium hypochlorite, but also with chlorinated isocyanurates. These are all loosely referred to as ‘chlorine’ or ‘bromine’. The following disinfectants are recommended for the water In pools:
a) chlorine gas/hypochiorous acid/hypochlorite solution, produced at the point of use (in situ) by electrolyzing sodium chloride solution (common salt solution, sea water or brine, as in EN 16401), hydrochloric acid or salt added filtrate;
b) sodium hypochlorite solution, as specified in EN 15077, containing 150 kg/t chlorine and about 12 g/l sodium hydroxide and having a pH value of about 11. During storage, the chlorine concentration decreases, resulting in a daily chlorine loss of about 1 g/l at 20 °C;
c) calcium hypochiorite, as specified in EN 15796, in granular, tablet or pellet form, containing no less than 65 % (rn/rn) Ca(OCl)2 and less than a mass fraction of 16 % water;
d) chlorinated isocyanurates: trichioroisocyanurate compounds, as specified in EN 15032; or dichloroisocyanurate compounds, as specified in EN 15072 and EN 15073;
There are also a variety of alternative disinfectants, which can be applied to pool disinfection some alone and others in combination with a primary disinfectant (in accordance with manufacturers’ instructions). It shall be mentioned that when using these disinfectants, the range of action is limited for the general requirements (effectiveness, quick reaction, residual effect, easy and quick analysis) and cannot be fulfilled all in parallel.
The most common alternative disinfection methods are:
a) ozone (very low residual effect), as specified in EN 15074;
b) Liv (no residual effect);
c) hydrogen peroxide (slow reaction), as specified In EN 16400;
d) potassium monopersulfate as specified in EN 16380 (slow reaction);
e) P11MB (poly hexa methytene biguanide) only used In association with hydrogen peroxide and an algicide (incompatible with some equipment).
Both a) and b) require a disinfectant residual to be used in combination.
NOTE At the time of writing this standard, the use of copper/silver (incompatible with some equipment) is banned in some European countries. In some other European countries Its effectiveness is being reviewed.
4.6 pH-adjustment
For pool water treatment, the pH value is of utmost Importance. The pH is a measurement value that provides information about the acidic, neutral or alkaline nature of a solution. The pH value has a large influence on the activity of the dosed chlorine, the chemical corrosion behaviour, skin and/or eye tolerance, as well as, if applicable, the flocculation process. Therefore, an important pool water treatment step consists of a corresponding correction of the pH value. If, and how much, acid (pH- decreasing) or alkali (pH-increasing) should be added to adjust the pH value depends on the water’s alkalinity, the disinfection method used, as well as on the level of pollution in the pool, and may be regulated and adjusted according to the manufacturers’ recommendations.
The reagents added should be thoroughly mixed with the water.
The following reagents may be used for pH value adjustment and/or stabilization:
a) sodium carbonate (as in EN 15362), sodium bicarbonate (as in EN 15075) or sodium hydroxide (as in EN 15076) If the pH value Is too low;
b) carbon dioxide (as in EN 15513), hydrochloric acid (as In EN 15514), sulphuric acid (as in EN 15078) or sodium hydrogen sulfate (as in EN 16038) if the pH value is too high.BS/EN 16713-3-2016 pdf download.