Final answer:
Clearances for listed water heaters refer to the required minimum distances that must be maintained between the water heater and surrounding objects or structures for safety reasons.
Step-by-step explanation:
Clearances for listed water heaters refer to the required minimum distances that must be maintained between the water heater and surrounding objects or structures for safety reasons. These clearances help prevent fire hazards and ensure proper ventilation and access for maintenance. The specific requirements for clearances may vary depending on the type of water heater and the applicable building codes. For example, a typical clearance for a gas-fired water heater might include a minimum distance of 6 inches from combustible materials and 1 inch from non-combustible materials.