A Mechanical Ventilation job involves the installation, maintenance, and repair of HVAC systems that regulate airflow, temperature, and air quality in buildings. Professionals in this field work with ventilation ducts, fans, air filtration systems, and controls to ensure proper air circulation. They may be employed in residential, commercial, or industrial settings to improve indoor air quality and energy efficiency. Their responsibilities often include troubleshooting system failures, performing routine inspections, and complying with safety regulations.