What is the maximum allowable protrusion of screws in dryer exhaust ducts into the inside of the duct?

The maximum allowable protrusion of screws in dryer exhaust ducts into the inside of the duct is 1/8 inch. This guideline is essential for maintaining the efficiency of the duct system and ensuring proper airflow. Protrusions that are too long can obstruct airflow, leading to increased resistance within the duct and potential blockages. By limiting the screw protrusion to 1/8 inch, it minimizes the risk of lint buildup and enhances the performance of the dryer by allowing for smooth airflow. This is crucial for preventing lint buildup in the ductwork, which can pose a fire hazard. Additionally, keeping the screws flush with the duct walls helps maintain the integrity of the exhaust system, ensuring it operates safely and effectively.