Summary of Diesel Vehicle Particulate Matter Emission Trial At Askham Bryan Agricultural College University of Leeds 2007


To study the effect of a Magnetic Field on the particulate matter emissions from diesel tractors using the Correct Magnet Fuel Ring.
This Project was submitted to the University of Leeds by Steven Charlesworth in part fulfilment for the award of a BSc(Hons) Sustainable Land Use Degree.


  1. Five tractors of varying Horse Power from 23 128hp were used. The original plan was to use tractors of similar horse power, 70 80hp but due to unforeseen technical reasons this was not possible.
  2. Smoke Analysis readings were taken using a Bradbury 1212 Smoke Tester.
  3. Readings were repeated on 5 separate days at approximately weekly intervals.
  4. Each tractor was subjected to 3 readings.
    1. Without a magnet installed
    2. 1 magnet installed
    3. 2 magnets installed
  5. The Fuel Ring was fitted after the fuel filter.
  6. Ambient temperature, atmospheric and weather conditions were recorded on each occasion.
  7. All readings were taken at the same engine oil temperature.


As tractors get older there is usually a build up of carbon deposits on the piston rings and housing. If this has occurred, the emissions are likely to increase during the initial stages, since the magnetic field from the Fuel Ring leads to the de-coking of the engine. Gradually the emissions begin to reduce as the engine is cleaned. This process can take up to a few weeks depending on the level of carbon deposit.


  1. No conclusion was reached on whether ambient temperature had an influence on emissions.
  2. There is a strong suggestion that High Pressure Weather leads to lower emissions.
  3. There is a strong suggestion that Low Pressure Weather leads to higher emissions.
  4. In older tractors fitting the Correct Magnet Fuel Ring can lead to an increase of emissions during the initial stages due to de-coking of the engine.
  5. The proximity of the magnet to the injectors is important for the efficiency of the Fuel Ring.

Summary of the Results

Average Results spread over 5 test days at approximately 1 week intervals.

Decrease / Increase % Emissions Litres/minute.

Tractor No. Age(yrs) Power Hp Working hrs 1 Magnet 2 Magnets
1 1 128 20 -23.8% -26.2%
2 16 72 946 +5.9% +4.9%
3 7 58 584 -14.1% -15.6%
4 1 80 71 -14.1% -14.2%
5 11 23 1336 -3.1% +0.9%
Average -9.8% -12.4%
Two Oldest Tractors
2 16 72 946 +5.9% +4.9%
5 11 23 1336 -3.1% +0.9%
Average +14.1% +2.9%
Three Newest Tractors
1 1 128 20 -23.8% -26.2%
3 7 58 584 -14.1% -15.6%
4 1 80 71 -14.1% -14.2%
Average -17.3% -18.7%


  1. These results confirm, what has been found previously in field assessments and is strong evidence that :-
    Specifically designed Correct Magnet Fuel Rings reduce Diesel vehicle Exhaust Emissions.
  2. This trial strongly suggests that a correctly applied Magnetic Field, fitted to the fuel pipe of older vehicles, which are likely to have engine carbon deposits, has the ability to de-coke the engine.
  3. This results in a cleaner engine which is then kept continually clean and reduces maintenance costs.
  4. A reduction in emissions suggests that there has been a more complete burn of fuel which must lead to a saving in fuel unless the extra power is used for speed performance.
  5. Field Assessments on a wide variety of vehicle have found that the Correct Magnet Fuel Ring produces saving in fuel. It is reasonable therefore to suggest that when engine emissions are reduced by applying a magnetic field through the fuel pipe that this has resulted in a more complete burn of fuel with an increase in engine power which, if not used, will automatically infer there is a fuel saving.
  6. Field Assessments have shown a saving of up to 1.25 Litres per tractor working hour.