I'm not sure how to link the two posts but interesting post on 'Honor Oak Park to be part of Air Quality Management Area' that Admin just posted.

This thread regarding traffic on Honor Oak Park was started along time ago and it's something I feel really strongly about, something which I believe can be easily remedied.

You just have to look at the state of the wall on the last white house on the left that was converted from a shop to a private residence(walkiking away from the station), all that muck on there I would say is visible dirt and poisonous fumes from car exausts that we're all breathing in daily.