Which of the following is an essential characteristic of both duct coverings and linings?

An essential characteristic of both duct coverings and linings is compliance with safety standards. This is crucial because both materials must meet various safety codes and regulations to ensure they perform effectively without posing risks, such as fire hazards or health concerns from emissions. Compliance with safety standards ensures that the materials used protect both the building's occupants and the structural integrity of the system throughout its lifecycle.

Choosing materials that adhere to these safety codes helps prevent issues like condensation, mold growth, and energy loss, which are critical considerations for maintaining air quality and system efficiency. Safety standards often encompass aspects such as fire resistance and insulation properties, which are vital for both duct linings and coverings.