If the enforcement of a code provision violates the conditions of the listing of a/an, then the condition of the listing and manufacturer's instructions must apply.

The assertion that the conditions of the listing and manufacturer’s instructions must apply when the enforcement of a code provision conflicts with the listing refers to the recognition of both equipment and appliances as governed by specific standards and manufacturer guidelines. Under the International Residential Code, it is crucial to adhere to the established conditions of a device’s listing, which ensures that the item operates safely and effectively as intended.

When enforcement of a code might conflict with these conditions, it underscores the importance of prioritizing the manufacturer's specifications and the certified conditions under which the equipment or appliance was approved. Neglecting these conditions could lead to safety hazards or malfunctioning items, thereby compromising the integrity of the installation and user safety.

Therefore, both equipment and appliances are covered within the context of this question. Recognizing their dual relevance provides a comprehensive understanding of compliance with safety standards and the importance of adhering to both code provisions and manufacturer instructions.