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Characterisation Method Information
Characterisation Method Name:
NOx impact on Base-cat-ion capacity
Version:
1999
Date Completed:
1999
Principal Method Name:
EPS: Equivalency method using SO2 as a reference
Method Description:
The characterisation factor is determined by an equivalency method using SO2 as a
reference.

When reacting with water and oxygen, 1 kg of NO2 may produce the same amount of protons as 0.5*64/46 = 0.70 kg SO2. When adsorbed by biota reactions may occur where N is reduced again and the net acid production is decreased.

The characterisation factor of SO2 for soil base-cat-ion capacity is determined in Base-cat-ion capacity of EPS for SO2 to 1.56 equivalents of base cat-ions per kg SO2. The characterisation factor of NOx is therefore 0.70*1.56 = 1.09 equivalents of base cations per kg NOx.
Literature Reference:
Steen B (1999b): A systematic approach to environmental priority strategies in product development (EPS). Version 2000 Models and data of the default method CPM report Chalmers University of Technology Sweden
Methodological Range:
The residence time in air in the order of a week and the residence time in soil is less than a year. The flow group is emissions anywhere on the globe during 1990. The environmental system investigated is therefore chosen to be global during 1990
Notes:

Existing Characterisation Factors of NOx impact on Base-cat-ion capacity
Characterisation Parameter Category Indicator Impact Indication Principle Aspect Substance Quantity Unit Notes
CFactor Base cat-ion capacity EPS/2000
Type = Emission
Direction = Output
Media = Air
Geography = *
NOx 1.09 H+ mole equivalence/kg