What must be done with vent terminals after a smoke test reveals their presence?

When a smoke test reveals the presence of vent terminals, sealing them is the appropriate action to take. Vent terminals play a vital role in maintaining the integrity of the venting system by allowing gases or vapors to safely exit the building. If a smoke test indicates that vent terminals are functioning or that there is a potential for gas migration, sealing them helps prevent any potential hazards associated with unwanted ventilation or the ingress of harmful gases from outside.

Covering them with insulation, removing them, or simply labeling them do not address the immediate concern presented by the smoke test results. Covering with insulation could obstruct proper ventilation, while removing them could compromise the ventilation system. Labeling them is useful for identification but does not mitigate any risks presented by their presence. Therefore, sealing the vent terminals ensures that they are either properly maintained or closed off as required by safety and code regulations.