NH3, NH4 +, NO3- and (HNO3 + NO3-) 24-hour measurements for filter samples (gas / aerosol).

Precipitation is collected during periods of between 24 hours and one month.

Technical description

Method:

• The particulate matter (NH4 + and NO3-) is collected on membrane filters
• The gases (NH3 and HNO3) are collected on impregnated filter.

Analyzes are performed either by ionchromatography or autoanalyzer. The filter samples are extracted by ultrapure water.

Due to the exchange between particulate and gas phase for HNO3 and NO3- only the sum is reported.