400watter and ventilation

Do I need ventilation for just one light? What about the smell? Should I buy a whole heat and charcoal filter system or just a light?

If your already thinking about getting a fan and filter do so you want good airflow with any lights

I will But could I have a intake and a out take for air? It´s winter and snow here. It would be too cold. Or just a charcoal filter hooked up to the light(airflow around light) then a fan and out.