Which labeling indicates compliance for smoke and draft control doors?

The labeling that indicates compliance for smoke and draft control doors is indeed the label “S,” which signifies that the door meets the requirements set forth in UL 1784, the specific standard for smoke and draft doors. This standard establishes important specifications for how these doors should perform, ensuring that they adequately prevent the passage of smoke and air during a fire event, which is crucial for occupant safety and building integrity.

Smoke and draft control doors are essential in maintaining safe egress routes and in limiting smoke spread throughout a building, enhancing life safety measures and property protection. The label “S” denotes that the door has been tested and certified to hold up against certain performance metrics related to smoke leakage, which is a vital consideration in fire protection.

Other labeling options provided do not correspond to the requirements for smoke and draft control doors. The label "D" might represent a different standard or requirement, while label "C" could refer to compliance with other fire-rated doors that do not specifically address the smoke and draft control factors. Additionally, stating that no labeling is required would contradict the regulatory framework that mandates identifying specific compliance standards in order to ensure safety protocols are followed.