Water analysis

The Technical Health Regulations for Swimming Pools in Andalusia, approved in Decree 485/2019 of 4 June, establishes the criteria that define the quality of bathing water in public swimming pools and the necessary corrective measures in the event of deviations. AquaVera carries out the controls established by the Decree using chlorine as a product for the treatment and disinfection of the water.

Sampling, monitoring and analyses is conductedduring three daily controls: one before the opening and two others at peak times. The parameters used are as follows:

• Chlorine Free Residual (CLR). Chlorine eliminates any type of bacteria, germs, algae or microorganisms that may be harmful. As it acts, the chlorine disappears from the water. What remains is what we call chlorine free residual. Its values must be between 0.5 and 2 mg/L.
• pH. The pH or hydrogen potential is a measure that tells us whether a substance is basic or acidic. It is expressed on a scale from 0 to 14, with 7 being the neutral value (neutral pH). Below 7, a substance is acidic; above 7 it is basic. Humans have a slightly basic pH (between 7.35 and 7.45), so we must control it to avoid adverse effects on bathers. In addition, a correct pH level is essential for disinfectants to do their job properly. The pH of swimming pool water should be between 7.2 and 8.
• Turbidity. Turbidity in swimming pool water can be due to various causes: very hard water, dust in the air, atmospheric temperature or incorrect water parameters. The regulations state that turbidity must be less than or equal to 5 UNF. In the east of Almeria we have very hard water and frequent westerly or southerly winds that carry a lot of dust. In these circumstances, it is important to have a correct pH level for the chlorine to work.
• Water temperature. Heat facilitates the evaporation of chlorine and causes it to lose its disinfectant power. When we measure high water temperatures (usually above 30^°C), we know that evaporation will be higher. In this case, we increase the chlorine input to compensate for this phenomenon.

We also measure parameters such as total chlorine, combined chlorine residual, transparency or recirculation time.