Important norms and guidelines for pool operation in Europe1 |
|||
|---|---|---|---|
| Parameter | Austria | Germany | Switzerland |
| BHygG/BHygV | DIN 19643 | SIA 385/1 | |
| Free chlorine (residual) | 0.3 to 1.2 ppm2 | 0.2 to 0.6 ppm2 | 0.1 to 0.6 ppm2 |
| Combined chlorine | = 0.3 ppm2 | = 0.2 ppm2 | = 0.2 ppm2 |
| pH value | 6.5 to 7.8 | 6.5 to 7.8 | 6.8 to 7.6 |
| Redox potential (ORP) | = 700 mV2 | = 700 mV2 | = 650 mV2 |
| Aluminum | = 0.1 ppm | = 0.1 ppm | N/a |
| Trihalomethanes (THM) | N/a | = 0.02 ppm | = 0.02 ppm |
| Turbidity | N/a | = 0.02 NTU | = 0.02 NTU |
| (filtred water) | |||
| Fresh water addition/dilution | = 30 L/pers./day | = 30 L/pers./day | = 30 L/pers./day |
| 1 To be amended 2011. | |||
| 2 If swimming pool operates at higher pH levels, higher free chlorine residuals are recommended. | |||
Chart courtesy Wapotec®
Conquering chlorination
Poor filtration also leads to another issue—higher chlorine levels. Take, for example, super chlorination and/or shock treatment. In North America, however, many operators still add greater and greater quantities of chlorine into public pools in order to maintain water clarity. In Europe, however, it has been widely accepted that adding more chlorine to a swimming pool will create more problems than it solves. In fact, numerous scientific articles around the world have documented that adding more chlorine produces increased amounts of toxic chlorine byproducts (CBPs). Tests have shown shock treatment can increase THM levels almost instantly by more than 400 per cent.
DIN standards provide not only an upper chlorine limit, but also a maximum reading for free chlorine; in North American jurisdictions, such as Alberta and Ontario, only a minimum level of free chlorine (0.5 ppm) is required by the provinces’ health acts. Switzerland’s SIA standards, for example, are similar to DIN and allow minimum chlorine levels to be as low as 0.1 ppm, with maximum levels of 0.6 ppm.
DIN sets the maximum levels of free chlorine to prevent the formation of CBPs, while up until recently, North American standards have only provided minimum guidelines based on drinking water research due to the lack of information on swimming pool water. The National Swimming Pool Foundation (NSPF), a non-profit organization focused on creating healthy pools and healthy bodies through aquatic education and research, has prompted more studies on recreational water, which looks to improve North American pool and spa water standards.
