Factory-built fireplaces must be _________ and installed according to the conditions of the listing.

The correct response emphasizes that factory-built fireplaces need to be both listed and labeled. This means they must come with a certification indicating they meet specific safety and performance standards set by recognized testing agencies. The listing usually refers to the manufacturer’s adherence to design standards, while the label indicates that the product has undergone the necessary testing for safety and compliance.

Following the conditions of the listing is crucial because it ensures that the fireplace is installed correctly to function safely and effectively. Listed and labeled fireplaces have been subjected to rigorous testing, which guarantees that they will perform as intended when installed according to the specified guidelines.

While other decisions might suggest various aspects of installation or assembly, adhering to the listings and labels is pivotal in ensuring the unit performs safely and meets all applicable mechanical code requirements.