Are you one of 38 million in the UK living in areas with illegal air pollution?

I'm not cherry picking anything, read where I said I got the info from. read where the info originates from. i stated that petrol puts out more pollution than diesel.

the rest is another commenter as i stated and the info from TFL

Quite interestingly, you can observe the effects of vehicles by looking at street-level pollution data immediately after large-scale vehicle restrictions such as during the London Marathon, RideLondon sportive and so on.

Immediate, drastic decreases in street level NOx pollutants, most noticeable in the high pollution spots such as Trafalgar Square and Oxford Street.

Next day as traffic is back to nromal and bag, it's through the roof again.

Meanwhile the Mayor is making various sweeping statements about his absolute commitment to maybe thinking about doing something at some point in the not-too-distant future. All nice and woolly.

It needs immediate and drastic action - not sticking paster solutions of a "pollution charge".

"If the level of NOX or particulates rise on an occasional basis due to unusual meteorological levels, this does not mean that 60% of the population are being poisoned."

But the frequency of 'unusual meterological levels" over time is likely to be constant (ignoring climate change for the moment!). So if those spikes in NOx occur more often in a location, it's likely that that location has generally high levels of pollution.

Having looked at the TfL report (or, 'puff piece', depending on how much one trusts TfL - that report seems quite keen on 'targets' and 'projections', which always inspires scepticism) it answers some of the questions, to be fair.

But I'd still like to know how they obtained those figures. I don't think one can put any faith in lab measurements of emissions by vehicles.

As well as the proven 'fiddling' the manufacturers have engaged in, every source seems to agree that levels can increase dramatically if there are any imperfections in the vehicle's engine. And given the number of cars I see with visible clouds of black crud pouring out of their exhaust, and the frequent stories of garages simply removing failed catalytic converters, I suspect UK vehicles are generally not maintained in perfect, rolling-off-the-production-line condition.

Also, even the figures in that TfL document, indicate that diesel vehicles contribute twice as much to particulate emissions in London as do petrol vehicles (it's just that many of those diesel vehicles are not cars).

Also, this seems relevant

http://www.livescience.com/52284-volkswagen-scandal-clean-diesel-challen...

@Behindthebikesheds

Those are pretty incomplete 'facts', though.

What _size_ are those particulates? That's pretty important - it makes a big difference to the health effects.

Are they based on real world street-level measurements (if so, how did they determine what was coming from which source?) or the bogus lab test figures for diesel?

Another point against black cabs, though, I see.

In any case, the problem is motorised vehicles, whether diesel or petrol, and that's what needs to be addressed.

Fair point that heating systems might not have had enough attention (though surely that effect would be seasonal?)

And yet the levels of pollution on our roads come more from petrol than diesel.

Here is a comment and some actual facts lifted from a commenter on the grauniad;

"The limits are specified at two levels, average levels and occasional incident levels.

If the level of NOX or particulates rise on an occasional basis due to unusual meteorological levels, this does not mean that 60% of the population are being poisoned.

If you had the level of smoke in your house 24/7 that you have when you are barbecuing in the garden or the park, you would soon be in trouble, but you don't and you aren't, so your burning of sausages or steak makes no difference to your life span. It is the same with air pollution.

The facts are these:

At a few congested sites - mostly in London, there is unacceptable pollution. Half of it comes from taxis. more than 23% of it comes from space heating, commercial and domestic and industry. 11% of the NOX in London air come from diesel cars. 29% of London's NOX comes from goods vehicles, buses and taxis..

Particulates in London come more from petrol cars than diesel ones. THESE ARE FACTS and you can see them in the TFL air quality document I link to below

This distorting article selects only one source and by far not the biggest - diesel cars.

See this TFL Mayor of London analysis of the sources of London's air pollution.

Figure 2

diesel car NOX contribution to overall nox 11%
TFL Bus NOX contribution to overall nox 8%
Goods vehicles NOX contribution to overall nox 17%
Gas heating NOX contribution to overall nox 16%
Machinery NOX contribution to overall nox 14%

Fig 3 Particulate Emissions % of whole.

Petrol cars 17%
Diesel Cars 11%
Goods vehicles 13%
Industry and heating 7%
Non mobile machinery 13%

http://content.tfl.gov.uk/transport-emissions-roadmap.pdf

Just reported in the news that the government are being taken to court because of their failure to meet air pollution targets.

And yet there are plenty of local authorities which clearly put driving above the health of their constituents, building more roads to cope with congestion in a never ending spiral of futility.  My own for instance, South Gloucestershire council. 

They recently got a few million from central government to address congestion, and they have a very clear congestion policy, which starts with providing for pedestrians and cyclists and ends with road building and widening.  You can guess what they are actually doing.

They also have clear policies about air pollution and health, including, you guessed, priority for active travel.

It going to cost, not just direct costs but knock on for GDP for the UK. You can't put a cost on health, can you?