This update to the guidelines for safe recreational water environments provides health-based guidance for setting national water quality standards and implementing preventive risk management at the local level. Risk management approaches monitor and reduce sources of pollution, including tools to let users know in real time when it is safe to swim.

链接地址：https://iris.who.int/bitstream/handle/10665/342625/9789240031302-eng.pdf?sequence=1&isAllowed=y