How to safely stop and start circulation

In might not seem like a big deal, but stopping and starting a commercial swimming pool treatment system is fraught with danger for those unaware of the hazards! In this video, I’ll go through the issues and discuss a real-life case study where several unfortunate swimmers were gassed due to procedural errors by the pool operators!


There is a risk of the generation and emission of extremely hazardous chemicals when power to the circulation pumps is cut (intentionally or because of power failure). A system should NEVER be restarted following a failure of the circulation system while there are people in the pool. If there is a concern that there may have been inadvertent mixing of chemicals within the pipework of the circulation system, the fire service should be contacted and the circulation and chemical dosing systems left stopped.