Which of the following is NOT a characteristic of vacuum exhaust systems?

The correct answer indicates that insulation is not a characteristic typically associated with vacuum exhaust systems. Vacuum exhaust systems are designed primarily for the safe and effective removal of gases or vapors from a facility, often in medical or laboratory settings.

Insulation is not an inherent requirement for the operation of these systems, as their primary functions focus on maintaining performance and safety during gas discharge. Proper discharge methods, such as directing exhaust into the atmosphere while avoiding places of public assembly, are essential for preventing exposure to harmful pollutants and odors, which aligns with the overall purpose of such systems. Additionally, minimizing odors is crucial for maintaining a pleasant and safe environment, particularly in healthcare settings.

The other options correlate directly with the design and operation of vacuum exhaust systems. These systems are engineered to handle waste gases responsibly, emphasizing both safety and the integrity of surrounding environments.