P10m's get in further than p20m's but p5m's modern petrol (and probably derv too) get in further and cause more damage. When you burn something you will always end up with particulates as you never get perfect combustion.

P10m's get in further than p20m's but p5m's modern petrol (and probably derv too) get in further and cause more damage. When you burn something you will always end up with particulates as you never get perfect combustion.

Sorry - yep when I said PM10 I meant PM10 and smaller. I always thought that the diesels were significantly worse than Petrols in this regard, particularly given the over fuelling nature and consequential higher particulate output of a diesel engine when floored or under high loads. I thought this was the reason for the DPF's being introduced, potentially across the board.

However you sound better informed than me (I am a few years behind on the data) so are modern petrols now considered as much of an issue re particulates and human health?

Either way it will all count for nothing if the emissions regs for public transport are not brought into line with those for cars. Cars are currently on EU V I think but from memory most widely run PSV's are still struggling to meet EU II?