If a plumber needs to temporarily leave a site after removing a CWSC in an occupied property, what is the primary safety precaution?

The primary safety precaution when a plumber needs to temporarily leave a site after removing a Cold Water Storage Cylinder (CWSC) in an occupied property is to ensure that the system is isolated and cannot be refilled. This is crucial because an unmonitored open system can lead to several safety issues.

When a CWSC is removed, the plumbing system may be left vulnerable to accidental filling, which can cause flooding or water damage in the property. Additionally, if water enters the system when it is not properly isolated, there might be backflow or contamination risks, potentially compromising the potable water quality.

By ensuring the system is isolated and cannot be refilled, the plumber effectively minimizes the risk of water flow into the system while they are away, safeguarding both the property and its occupants. This action helps to maintain overall system integrity and prevent any unwanted incidents during the temporary absence from the job site.