Performed air duct cleaning on a residential HVAC system using the fogging method. Applied an antimicrobial fogging solution throughout the ductwork to eliminate mold, bacteria, and allergens. The fog was evenly distributed through the ducts to ensure thorough cleaning. After the fogging process, tested the system to verify improved airflow and air quality. This method will enhance the indoor air quality and increase the overall efficiency of the HVAC system, reducing potential health risks.