Filtration soiling is a problem that affects many carpets.
You can recognize filtration lines easily.
They show themselves as dark lines around walls and underneath doors.
In this article I will explain how these lines are formed and what can be done about them.
Filtration lines form when your air conditioning and heating system blows air into your room.
The air is blown into a room effectively pressurizing it.
The air must go somewhere so it goes underneath walls and closed doors to equalize the rooms pressure.
The carpet along this area acts as a filter.
It traps the fine particles of dust and soot that are in the air.
These fine particles are difficult if not impossible to remove.
If you have these lines your first step is to call a professional carpet cleaner.
They will have the knowledge to get rid of the lines.
You could try home spotters but the residue lef behind would probably cause the lines to reappear later and they would probably be worse.
If you get rid of the lines or just want to prevent them, there are some steps you can take.
Filtration lines are worse if you burn candles, incense or oil burners so use them sparingly.
Also try to leave doors to rooms open as much as possible.
This gives the air a place to go besides under your walls.
Lastly you can use quality air filters in your HVAC system that filter smaller dirt particles.
That's about all you can do.
Unfortunately filtration lines are just a part of owning carpet.