Pollution from tractors and non-road vehicles and machinery
3 Summary and conclusions
For a number of years, busses and registered vehicles for transport of goods have been regulated in order to decrease their emission. As a result of tighter rules and by that a decreasing pollution from this sector, the relative pollution from other sectors is increasing.
In EU, new directives have been introduced for tractors and other non-road vehicles and machinery. The EU directives have been established as law in Denmark through "Detailforskrifter for Køretøjer" by Danish Road Safety and Transport Agency, and a government order from Danish Environmental Protection Agency.
Present investigation shows that new vehicles are delivered with engines marked according to the directive. The suppliers know that modification of engines is not allowed and tries to persuade their customers to use their supplier network for all service on the engines that can influence on the emissions.
On the other hand, there is no doubt that the owners of the vehicles and the companies
dealing with used machinery or carry out maintenance and
adjustments will need more information. It will take some years before approved tractors,
vehicles or machines are common in the sector and before it is known that engine
modification is not allowed if it means that emissions change. If a control scheme was
introduced, it would reduce the possibilities for readjusting the engines and the emission
level would be kept down.
Analysis of the non-road sector's fuel consumption and emissions compared to the road sector (data for this sector is supplied by the National Environmental Research Institute in Denmark) show that:
 | The consumption of diesel in the non-road sector is approximately 31% of the consumption in the road sector. Emissions of CO, HC, NOx and particulates from the diesel engines are about half of the emissions from the diesel road vehicles. However, the SO2 emission from the diesel vehicles in the non-road-sector is more than three times higher than the diesel road vehicles. |
| The consumption of petrol in the non-road sector is approximately 4% of the consumption in the road sector. The HC and CO emissions from the petrol engines is about one third of the emission from the cars in the road sector. |
| In total, the CO2 emission from the non-road sector is approximately 17% of the CO2 emission from the road sector. The emission of CO, HC and NOx is about 20, 25 and 30% respectively of the total emission from the road sector while the emission of particulates is nearly half the emission of particulates from the road sector. The SO2 emission from the non-road sector is about one and a half (1.5) times the SO2 emission from the road sector. |
In total, the non-road sector contributes considerably to the emissions compared to the road sector.
Compared to 1990, the reduction of sulphur in diesel oil has resulted in a reduction of SO2 of about 80%. In addition, the emission of NOx and particulates is reduced significantly, while the emission of HC and CO has decreased just as the fuel consumption. Compared to 1990, the fuel consumption is reduced with approximately 12%.
This survey is subject to an uncertainty of 36% as regards calculation of the fuel consumption and of 40% as regards calculation of the emissions. This corresponds approximately to the survey in 1990.