3 weeks ago I stripped my flowering room out and sprayed everything with a bleach solution, wiped that down, then sprayed again with a H2O2 solution AS A PRECAUTION!
I had given a friend some plants which he flowererd but either one hermied or pollen got to them somehow. I didnt want the stuff near my grow since I have people relying on me for their meds, hence the paranoid cleaning frenzie!
I believe I read here somewhere that pollon can affect 3 or 4 grows after a room has been exposed, 4 grows would be 8 months.
If in doubt, clean it out! The way I saw it was either clean the room or have a ruined crop, er, let me think, which do I prefer!
Green mojo fella and have fun cleaning

Peace W