Dec 08 2014

3 The Environmental Audit Committee Evidence that is NOT in the Report


Written evidence submitted by David Davies.


1/Introduction Thousands of people throughout the UK are dying from Air Pollution confirmed by a recent World Health Organisation report. The Government and Local Authorities have failed to implement effective Air Quality Strategies and the EU is taking action to fine the UK.

In May 2013 The Supreme Court has declared that the Government is failing in its legal duty to protect people from the harmful effects of air pollution.

In London improper and unlawful Air Quality transport policies have failed to reduce harmful emissions and these ineffective policies are replicated nationwide. The Environmental Audit Committee itself filed a damning report in 2011 requesting that the Government and Local Authorities take urgent action. This request has been completely ignored. The only way that urgent effective action will take place is if it is fully understood why air quality strategies have failed. A Public Inquiry into the thousands of deaths caused by pollution each year throughout the UK for which the criteria are fully met, is the ONLY mechanism which will fully scrutinize the evidence as to why previous air quality strategies have failed allowing effective strategies to be implemented going forwards.

2/ Background My personal background is mechanical and production engineering. I have previously designed and developed an emissions reduction system for London Taxis, which successfully significantly reduced the emissions of 2300 London taxis. I am extremely conversant with the technical requirements for emissions reduction and during the course of 2012/13 provided technical information and explanations to Professor David Carslaw of the Environmental Research Group at Kings College who had conducted emissions testing of 100,000 vehicles in London. The tests had shown that newer Euro standards and technologies used to achieve those standards had not improved emissions in an urban environment and I provided information and explanations as to why.

3/ Solutions.

In relation to transport there are many simple and effective solutions which have been suggested and ignored.

In London one of the biggest causes of pollution is from diesel vehicles.

3.1 A regulated engine cleanup programme could significantly reduce emissions of all diesel vehicles (including new vehicles).

3.2 Cleaner fuel could be used to reduce emissions for all diesel vehicles . In Sweden a ‘ Grade 1’ diesel is used which reduces PM (Particulate Matter) by 30% and Nitrogen Dioxide (NO2) by 10%. This is a simple and effective solution which would have a significant and immediate effect and yet has been ignored.

If the Government were to implement a regulatory requirement that all diesel sold in the UK was to be the improved Grade1 Diesel as used in Sweden the reduction in pollution would be massive and immediate.

This would have a far greater impact on improving Air Quality as unlike other measures it would clean up every single diesel engine (including static engines) and this would happen instantly at no cost. There would be no requirement for expensive regulatory control and enforcement of such a scheme or prolonged in service conformity testing.. The improved diesel would give a slight improvement in fuel efficiency. It could also be the case that the Government could offset any slight increase in cost by a slight reduction in Duty, knowing that this money will be saved in reduced health costs.

Once such policy is implemented the benefits would be widespread and automatic

Every other solution that has been proposed to reduce diesel emissions would only improve a small proportion of vehicles and at great cost over a long period.

Below is some information about Clean Diesel taken from a report by the Swedish Transport Authority.






Diesel fuel is the most widely used energy carrier in heavy duty vehicles such as long-haul trucks, coaches and busses all over the world. Besides heavy duty vehicles diesel fuel is also used in non-road mobile machinery, i.e. construction equipment and agricultural and forestry machinery. In these sectors, cost reduction is important and thus the energy efficiency of the engine. Diesel engines are more fuel efficient and has a better engine torque distribution compared with gasoline engines [1]. However, the resulting engine exhaust gas emissions from diesel fuels have a negative effect on human health and the environment [2, 3].

Studies have shown that transport related air pollution results in premature deaths of the same magnitude as traffic related accidents [4, 5]. Estimates in Europe by the Commission’s Clean Air for Europe (CAFE) programme shows that health effects related to air pollution, especially particulate matter and ground level ozone, are responsible for approximately 270 000 to 370 000 premature deaths annually from year 2000 to 2010 within the Community [5]. Exhaust gas emissions from diesel engines contains several pollutants such as particulate-bound polycyclic aromatic hydrocarbons that are highly carcinogenic or has other adverse health effects [6, 7].

With improvements on the engine and the diesel fuel the harmful pollutants can be reduced. In the European Union engine exhaust gas emission from heavy duty diesel engines are regulated through different directive and regulations depending on the date of placing on the market [8, 9, 10]. Since the first regulation was introduced, Euro I in 1992, the limit value for nitrogen oxides and particulate matter have been reduced with more than 95 percent. Besides engine exhaust gas regulation, emissions are also affected by the composition of the fuel [11, 12, 13]. Sweden has had a unique situation in the world regarding diesel fuel quality. For the last decade the dominating diesel fuel in Sweden has been the sulphur free, low aromatics “Environmental Class 1” (MK1) diesel fuel [14, 15]. Sulphur free corresponds to a maximum content of less than 10 ppm on mass basis. This fuel has been used in the transport sector and by non-road mobile machinery.

The European diesel fuel standard, EN 590, has gradually reduced the maximum content of sulphur from 2 000 ppm in the early 1990-ies for both on-road and non-road application to 10 ppm in 2004 for on-road and in 2011 for non-road [16, 17]. When the MK1 was introduced in Sweden the European diesel fuel standard had no requirements for either aromatic content or polycyclic aromatic hydrocarbons (PAH). While MK1 was limited to maximum content of 5 percent and 0.02 percent by volume of aromatics and PAH’s respectively the corresponding content of European diesel fuel was in the order of 20 to 25 percent of aromatics and up to 5 percent of PAH. Today the difference has been reduced but European diesel fuel still contains more than 10 times the PAH and around 3 times the aromatics compared with Swedish MK1 diesel fuel.

A literature study of the engine exhaust gas emissions from on-road engines from pre-Euro up to Euro III and non-road Stage I technologies fuelled with European diesel fuel and Swedish MK1 diesel fuel shows a significant emissions benefit with the Swedish MK1 fuel [12, 13]. The test has been performed with modern low sulphur European fuel and the results are reported below. The use of Swedish MK1 fuel had a positive effect on the emissions of both particulate mass and nitrogen oxides. Emissions of particulate matter were reduced with approximately 10 to 30 percent depending on the tested engine and test cycle. The relative results were independent from emission reduction technology, i.e. Euro or Stage level. Similar trends were found for emissions of nitrogen oxides where the use of Swedish MK1 diesel fuel reduced the emissions in the order of 10 percent compared with the class 3 diesel fuel.

It is important to notice that even if the relative difference in emissions between MK1and EN 590 diesel fuel were persistent over the various engine technologies tested, the absolute amounts were reduced in the same order as prescribed in the European emission regulations. However, that effect was not observable for emissions of PAH, thus the absolute emissions was rather constant from one engine generation to the next. The use of Swedish MK1 diesel fuel had a significant impact on emissions of PAH, ranging from a reduction of 40 to 90 percent compared with EN 590 diesel fuel.

However, although the data investigated indicates clear environmental and health benefits with the use of Swedish MK1 diesel fuel the results are inconclusive for modern engines with state of the art engine exhaust gas after-treatment technology. It is essential to investigate whether MK1 still have an emission benefit for engines fulfilling the Euro V regulation or better as these engines will have a significant impact of the future air quality and health effects.

In this study emission results from tests performed on two heavy duty vehicles (emission standard Euro V) fuelled with the Swedish MK1 and European diesel fuel fulfilling the standard EN590 are presented. The tests have been carried out on a chassis dynamometer and the vehicle has been driven according to the WHVC test cycle. The study comprises comparisons of regulated components, CO2 and fuel consumption. The particulate matter have been collected on filter according to the standardized method, as well as measured second-by-second with a TEOM instrument.

In addition to the regulated emission components the particle size distribution has been measured with an ELPI instrument. Unregulated components i.e. olefins, PAH and aldehydes have been analyzed. Extract of the particulate and semivolatile phase has been used to carry out the Ames’ bio assay to analyze the level of mutagenicity in the exhausts.


The use of diesel fuelled vehicles for transportation shows no tendency to decline, rather the opposite. For heavy duty vehicles and non-road mobile machinery diesel is, and will be (at least in the near future), the dominating fuel. Since vehicles are expensive, the transport sector will always be a mix of different emission standards. This puts focus on the fuel, since improvement of the fuel is the easiest way to improve the emissions from all diesel vehicles.

In this study a comparison between two different diesel fuels have been made – the Swedish Environmental class 1 (MK1) and diesel fulfilling the European diesel standard EN590 (MK3). The main difference between these fuels is the content of aromatics and polycyclic aromatics (PAH), of which many are known or potential carcinogen. The MK3 fuel contains more than 10 times the amount of PAH in %m/m compared to the MK1 fuel.

Earlier studies have shown significant differences between these two fuels. There have however been improvements both regarding the fuels and engine technologies. The goal for this study was to see if the differences persist.

Two modern (emission standard Euro V) heavy duty vehicles, equipped with a SCR and an EGR after treatment systems, were tested with the two diesel fuels. The vehicles were driven according to the WHVC test cycle on a chassis dynamometer. Regulated exhausts, CO2 and fuel consumption were measured. The gaseous components were sampled in bags as well as measured second-by-second. Particles were sampled on filters and analysed gravimetrically. The size distribution of the emitted particles was measured with an ELPI instrument. Unregulated components such as olefins, PAH and aldehydes have been analyzed. Extract of the particulate and semi volatile phase has been used to carry out the Ames’ bioassay test to analyze the level of mutagenicity in the exhausts.

This investigation has shown that there are still significant differences on emission level between these two fuel qualities even when tested on a modern, Euro V vehicle. There are discrepancies between the fuels regarding fuel properties and the effects on the emissions can depend on several parameters. The health effect of each of these parameters has however not been investigated in this study. For regulated components, the exhaust emission measurements have shown higher levels of NOx, PM and CO for the MK3 fuel. Regarding the unregulated components there are also some differences between the fuels. The total amounts of aldehydes are emitted to a higher extent when MK3 is used. The olifines investigated in this study, together with emissions of benzene, were too close to the detection level and no significant differences could be observed. The difference regarding emitted aromatics and polyaromatics must however be highlighted, where the higher levels of these compounds in MK3 is reflected in the exhaust emissions. The extracts of PAH used for Ames’ bio assay show higher mutagenic activity for the MK3 fuel. The continuous development of engines and reduction of emissions is enforced through legislation. Since the first regulation was introduced, Euro I (effective from 1992), the limit value for NOx and PM have been reduced by more than 95%. The emission limits in Euro VI for heavy duty vehicles, effective from 2013 (new registrations) and 2014 (all registrations), will lead to a more extensive use of after treatment systems (such as SCR and diesel particulate filters) in vehicles, in order to comply with the legislation limits. It is however of importance to point out that an SCR system has to work during suitable conditions, i.e. engine load and exhaust temperature, in order to reduce emissions in a satisfying way outside the test cell (one great challenge is emission reduction on buses in urban areas). The more extensive use of diesel particulate filter will probably have positive effects on emissions of particle matter, particle number as well as PAH emissions. For non-road mobile machinery there is however no enforcement for diesel particulate filters driven through legislated emission limits. The major benefit when improving the fuel quality is that this factor affects emissions from all existent vehicles and non-road mobile machinery, whereas the legislation can affect emissions in the future.

3.3 HGV vehicles are among the most polluting and these vehicles cause the most pollution when they are ‘stop starting ‘ in traffic.(A vehicle causes most pollution when the engine is under load i.e. you see smoke for the back of a truck or bus when it pulls away from a stationary position and not when it is driving along)

A simple solution would be to implement a peak time delivery ban on HGV vehicles. This does not necessarily mean they have to deliver at 4 am, it just means that they are restricted from delivering at peak times i.e. between 7am and 9 am and 5pm and 7pm. This would result in a significant reduction in pollution for the most polluting vehicles but would also improve safety for cyclists. It would also allow the remaining traffic to flow more freely and reduce the pollution from these vehicles as well. This has been ignored by the Mayor since it was proposed more than 3 years ago.
3.4 Effective Traffic management in cities is a simple and cost effective way of reducing emissions. In London in particular many restrictions are ignored; a single van or truck improperly stopped can cause massive disruption to traffic flow. Again vehicles create pollution when stop starting and this can be avoided if effective traffic management in implemented.

3.5 Pedestrian foot bridges could minimize the use of pedestrian crossings and significantly improve traffic flow.

3.6 Many cities have implemented Park and Ride schemes, however in London this has not happened. Car Parks near the M25 with fast train connections or shuttles to central London could significantly reduce the number of vehicles in Central London.

3.7 There has been very limited improvement in cycling infrastructure . It should made easier for cyclists to cycle to their local station, take their bike on train, cycle to their destination on a safe cycle route and then store their bike securely when they arrive there. There are many disused railway tracks and tunnels in London which could be easily used as cycle routes.


4/Public Law

It is a requirement of Public Law that decisions made by a Public body are rational and evidence based, for proper purpose, proportionate and properly reasoned. (ref.2)These criteria exist to ensure that decisions result in effective policies and strategies.  It is extremely important to acknowledge that these criteria are not just an obligation they are legal requirements and the failure to comply with these requirements is the reason why air quality strategies have failed.

5/ Transport.

5.1 Transport is one of the biggest causes of Air Pollution, particularly in urban environments.

There are many simple and cost effective solutions to reduce pollution from transport which have been ignored.(see para. 8 below)

In London 4267 people a year die from pollution. Boris Johnson has been Mayor for 6 years in which time 25,602 people have died from pollution yet he has not implemented a single effective policy to reduce pollution. This is confirmed by Air Quality Measurements

5.2 The failed Air Quality strategies implemented by the Mayor of London are replicated by Local Authorities throughout the country, who falsely believe that because they have been implemented in London that they must be effective. In fact the Mayor of London’s strategies do not comply with Public Law; they are not evidence based, properly reasoned, rational or for proper purpose.

5.3 He tried to cheat air quality measurements by spraying dust suppressant at the air quality test measurement locations.

5.4 He has wasted millions of pounds of Public money on his vanity ‘New Bus for London’ or ‘Boris Bus’ project. If this money had been spent on existing available Hybrid buses there would have been a massive reduction in pollution.

5.5 The Mayor of London claims in his letter to the Committee dated May 8th 2014 that he has reduced pollution in London by ‘retiring 3000 of the oldest, most polluting taxis’.

In written evidence that the Mayor of London submitted to the Committee in 2011 he stated (ref.3)

‘’11. NO2 levels have not fallen in recent years as modelling had predicted. This is a problem across major cities in the UK and across the EU. Emerging evidence, including a report by King’s College London, suggests that this may be due to the failure of recent Euro standards to deliver expected reductions of NO2 [1]. A Euro 5 car, for example, emits around five times as much direct NO2 as a fifteen year old car.’’

In this report he acknowledges that he had seen a report from Kings College London (prior to 2011) and that a new Euro 5 car would emit around five times as much NO2 as a fifteen year old car.

The Mayor of London had previously stated the same in his Air Quality Strategy report of 2010 (ref 4)

He then implemented a taxi age limit needlessly scrapping the fifteen year old taxis, which he knew would not reduce pollution at all. In fact it has been proven to have failed by a Defra report in May 2013 following testing in London carried out by the Environmental Research Group at Kings College London who tested the emissions from tens of thousands of vehicles. (ref .5)

The results of this testing confirmed what the Mayor had said in his statement more than two years earlier and before he implemented the taxi age limit; that the newer taxis actually created MORE NO2 than the older taxis.

A report by the highly regarded and extremely credible Professor David Carslaw of the Environmental Research Group, Kings College , published in July 2014 indicates that Oxford Street may be the most polluted street in the world.


The Mayor of London has dismissed this very credible scientific evidence as ‘an urban myth’ again claiming that he has reduced pollution by ‘removing 3000 of the most polluting taxis from the road’.

This is yet again a complete contradiction of his own evidence; he has acknowledged in his 2011 report to the EAC that the newer Euro 5 vehicles create MORE NO2 than 15 year old vehicles, yet claims that he has reduced pollution by scrapping the older vehicles.

He may claim that there has been a slight improvement in PMs , however this could have been achieved by retro fitting a Partial Flow Diesel Particulate Filter which would have reduced the PMs by just as much but without the NO2 increase of a Euro 5 vehicle. 5.6 The Mayor was asked on many occasions in Mayors questions by London Assembly Members to conduct proper emissions testing BEFORE he needlessly scrapped taxis, to prove that this strategy would actually reduce pollution. It is a requirement of Public Law for decisions to be evidence based so it would be reasonable to conduct at least some basic testing of taxis.  The Mayor point blank refused to conduct any testing whatsoever, instead relying on the fact that the newer vehicles were Euro 5 and therefore would be cleaner, even though this completely contradicted his own written evidence that he had submitted to the Environmental Audit Committee in 2011.

6/ Public Inquiry It seems that the Government has taken no notice of its own Environmental Audit Committee, The Supreme Court and the European Union. The ONLY reasonable solution is for the failures to be properly investigated in the format of a Public Inquiry. In 2012 ALL of the London Mayoral candidates formally supported a call for a Public Inquiry to investigate the failure to stop the thousands of deaths each year from pollution in London.

Certain characteristics can be identified in those public inquiries that have taken place:

  •                Widespread loss of life
  •                Threats to public health or safety
  •                Failure by the state in its duty to protect
  •                Failure in regulation
  •                Shocking events
  1.            Allegations of serious misconduct and prima facie merit have been made against those acting, or purporting to act, on behalf of the state and
  2.            Those allegations are sufficiently widespread and are being treated sufficiently seriously by those outside Government to undermine the public’s confidence in the integrity of the State and in the rule of law and
  3.            The allegations relate to a sufficiently defined event or series of events to allow an inquiry to be given proper and clear terms of reference and

An inquiry would represent the most effective means of establishing the merit of the allegations made and so of restoring public confidence.

It is the best possible way of establishing why previous air quality strategies have failed so that these mistakes are not repeated and proper effective urgent action is taken to reduce pollution and prevent thousands of deaths each year.



I would urge the Environmental Audit Committee to support the Campaign for Air Pollution Public Inquiry and initiate the process for this to happen.

This is the only way that the Government will be forced to take the urgent action that is required to prevent the continued thousands of deaths each year from pollution in the UK.

Dave Davies


Declaration of Interests

My company Eco-Power Ltd had previously designed, developed and distributed an emissions reduction system for London Taxis and had also recently proposed a Euro 6 petrol engine conversion of London Taxis which would have significantly reduced pollution but was refused by TFL. Eco-Power Ltd has also put together a diesel engine clean upwhich will significantly reduce pollution.

I have no commercial interest in Clean Diesel or any traffic management schemes which would reduce pollution.



Ref 1-Green Party Press Release


Ref 2 –Legal Requirements of Decisions by a Public Body


Ref 3-The Mayor of London’s written evidence to the EAC in 2011


11. NO2 levels have not fallen in recent years as modelling had predicted. This is a problem across major cities in the UK and across the EU. Emerging evidence, including a report by King’s College London, suggests that this may be due to the failure of recent Euro standards to deliver expected reductions of NO2 [1] . A Euro 5 car, for example, emits around five times as much direct NO2 as a fifteen year old car.

Ref 4-The Mayor of London’s Air Quality Strategy 2010.



Improving the emissions from all vehicles through new technologies

3.6.14. Euro air quality standards play an important role in driving improved performance on emissions. They were developed to ensure that natural fleet replacement results in significant reductions in pollutant emissions. They are also used by policymakers to specify requirements within different policies and schemes. Their ongoing development is therefore vital, with a focus on ensuring they are as effective as possible in delivering the benefits in reduced emissions that they have been designed to achieve, particularly when combined with abatement technologies.

3.6.15. Research into the application of Euro standards has highlighted that the higher standards do not deliver the expected improvements in emissions of NOx, especially for diesel cars and LGVs. Over the past few years, the amount of NO2 emitted directly by these vehicles has increased and overall NOx emissions (which include NO2) have tended to stabilise (rather than reduce), whilst improvements have been seen in HGVs and buses, more so since the introduction of the Euro IV standards for these vehicle types.

3.6.17. The Mayor will encourage the Government and the European Commission toensure that future Euro standards deliver improvements in emissions in order toimprove air quality in London. The Mayor will all also seek to make the case forimprovements to the testing and enforcement processes for Euro standards; forexample, the vehicle approval processes and testing standards could better reflect the actual on-urban road emissions of vehicles, as opposed to those derived from the figures obtained in laboratory conditions or based on drive cycles that are notrepresentative of urban driving conditions.

Ref 5-Report from the Environmental Research Group, Kings College 2013.



Ref 6 Testing by Swedish Transport Authority showing significant reduction in emissions by using cleaner diesel.


Ref 7 –City Diesel


City Diesel City diesel is petroleum based lower emission diesel developed in Sweden but now available in many European Countries including the UK. Exhaust emissions from vehicles fuelled with city diesel compare favourably with exhaust emissions from equivalent vehicles fuelled with conventional diesel. The main benefit of city diesel is that its combustion reduces particulate emissions by 34 – 84% depending on engine type, duty cycle, test basis and type of particulate measured. An additional benefit of city diesel is that it is a low sulphur fuel, which is necessary for the optimum running of oxidation catalytic converters.


2 August 2014