To ensure safety, combustion appliances must be inspected and tested for which of the following?

The focus on inspecting and testing combustion appliances for combustion byproducts is crucial for safety. Combustion byproducts include harmful gases such as carbon monoxide, nitrogen oxides, and unburned hydrocarbons, which can pose serious health risks if they accumulate in living spaces. Regular inspections ensure that appliances are functioning properly and venting these harmful gases safely to the outside environment.

By thoroughly checking for combustion byproducts, technicians can identify any issues, such as incomplete combustion or malfunctioning venting systems, that may lead to dangerous situations. This inspection helps prevent accidents and health hazards, ensuring that the appliances operate safely and efficiently.

While the other options may be relevant in various contexts—such as compliance with aesthetic standards being significant for visual appeal, efficiency ratings indicating how well appliances perform, and manufacturer warranties addressing repairs and replacements—they do not directly relate to the immediate safety implications associated with improper management of combustion byproducts. Therefore, the key priority in ensuring the safety of combustion appliances lies in the monitoring of these byproducts.