scope:

This standard describes the specific requirements for methods of determining the bulk deposition and the wet deposition of water-soluble anions and cations. The general requirements for the type, design, siting and exposure of sampling systems are covered by VDI 4320 Part 1. This standard can be used to determine the deposition of water-soluble anions (e.g. chloride, nitrite, nitrate and sulphate) and water-soluble cations (e.g. ammonium, sodium, potassium, calcium and magnesium). Where required by the measurement objective, it also allows the determination of further water-soluble ions. Depending on the site and the analyte, the measurement results obtained may vary with the type of collector employed

Typical applications include:

• background measurements to investigate the deposition of air pollutants subject to long-range transport (e.g. spatial distribution and temporal trends)

• measurements performed as part of the permitting procedure for plants, e.g. to determine

− the background concentration and the additional impact as per TA Luft (Technical Instructions for Air Pollution Control)

− eutrophying and acidifying depositions in fauna flora habitat (FFH) conservation areas as part of FFH compatibility assessments

− atmospheric nitrogen depositions in permitting procedures for livestock facilities [4]

• the measurement of substance depositions for the purpose of calculating mass balances or determining nutrients inputs (e.g. nitrogen)

• verification of the effectiveness of emission control measures

• traffic-related measurements (e.g. to complement the determination of road salt in particulate matter)

The sampling procedures here presented may also be used to determine metals and metalloids in atmospheric deposits at high-rainfall background sites (rural sites and moderately polluted urban sites) (e.g. determination of As, Cd, Pb and Ni as per DIN EN 15841 for reporting to the European Commission, for instance). Analysis methods for further elements are described in VDI 2267 Part 2.

Species that are not dissolved in the sample are not captured by the procedures described in this standard.