When can sprinklers be installed with a closed valve?

The appropriate scenario for installing sprinklers with a closed valve involves situations where the system is constantly attended. This means that there is an individual present at all times to manage the system and respond to any potential issues that may arise. The rationale behind this requirement is rooted in safety. If a sprinkler system is installed with a closed valve, it will not be operational in the event of a fire. Therefore, constant supervision is necessary to ensure that any emergencies can be addressed immediately, and the valve can be opened to activate the sprinkler system if needed.

In contexts where the system is not monitored or attended, such as when it is left alone or unmonitored, the risk of a fire occurring without adequate firefighting measures in place is significantly increased, making this practice unsafe. Additionally, during system testing, it is often required for the valve to be open to ensure that the system operates correctly, and options regarding residential buildings may have specific codes and regulations that typically require systems to be functional at all times when installed. Thus, constant attendance is the critical factor that justifies being able to install sprinklers with a closed valve.