Which component is NOT a part of a mine ventilation system?

The correct choice is the heating elements, as they are not typically considered a standard component of a mine ventilation system. Instead, a mine ventilation system primarily focuses on the movement and circulation of air to ensure a safe working environment for miners.

Blower fans are essential for introducing fresh air into the mine and maintaining airflow, while air filters are crucial for removing particulates and pollutants from the air, ensuring that the air quality is adequate for workers' health. Exhaust ducts play a key role in expelling stale air and harmful gases from the mine.

In contrast, heating elements are not a standard part of ventilation systems; while they may be used in some contexts, their primary purpose is to provide warmth rather than to facilitate air circulation or quality, which is the core function of a mine ventilation system.