This is to initialize a repository "Classification of Immissions".
The objective of this study is tocdetermin the effect of various emission sources
 on local immissions especially in urban environment. 
General background:
Local immissions are measured in the European Union at various sampling stations.
 Immissions may also be calculated from emissions using computer simulations. 
 The result of the simulations are summary values per volume element.
To reduce immissions  emissions have to be reduced.
 The effectiveness of alternative methods  reduction of emissions is measured or 
 calculated depending on the type of the source.As a second step the reduced emissions 
 are used as input of simulation models.The output of the simulation models are maps with  
 2 or three 3 dimensional cells.Because of various assumptions (mostly simplifications) 
 made and  limitations of computer capacity, the accuracy of the results need to be  
 verified. 
Local immissions at measured at various sampling stations.
The measurement method to be used in the EU is "Chemilumineszens".
 For these measurements a standard has been defined in EN 14211.
 These measurements are strongly disturbed by noise. 
 The variance of the anual mean beeing about 15% at low anual means of about 40 μg/m3.