An inline fan, also known as a duct or exhaust fan, plays a vital role in indoor gardening setups, including cannabis grow rooms. Its main purpose is to maintain proper airflow, ventilation, and temperature control within the environment.
Growers position it in the ventilation system, either at the beginning or end of the airflow path, depending on the size and needs of the grow space. When turned on, it creates negative pressure, removing excess heat, humidity, odors, and stagnant air for a healthier environment.

Inline fans come in various sizes and airflow capacities, allowing growers to choose a model that suits their setup.
Growers can also use them with carbon filters to reduce odors. Proper ducting and sealing are essential to prevent air leaks and maintain negative pressure. Some models have adjustable speed controls for precise environmental control.