Carbon air filters are the filters most used to remove gases. They are designed to filter gases through a layer of activated carbon and are usually used to combat volatile organic compounds (VOCs) such as car exhaust from Poor door and window seals.They are also often used to remove odors from the air, such as the smell of tobacco smoke or common source of car smell is not from your car at all; spilling, dropping, or forgetting something stinky in your vehicle can leave a lingering odor.