How long can spillage from vented appliances last before indicating a failure?

The correct duration for spillage from vented appliances before indicating a failure is 60 seconds. This timeframe is critical for safety assessments during a combustion appliance test. When spillage is detected during the testing phase, it serves as a warning sign that there may be issues with the venting system or the appliance itself.

If spillage continues for 60 seconds, this extended duration indicates that there is insufficient draft to remove combustion gases effectively, which could lead to dangerous conditions such as backdrafting or the release of harmful gases into the living space. This requirement ensures that any potential safety risks are identified promptly, and corrective actions can be taken to address the venting issues, thus preventing any health hazards for occupants.

Understanding the 60-second guideline is integral for professionals working with combustion appliances, as it helps them ensure compliance with safety standards and protect the well-being of users.