MARGA stands for Monitor for Aerosols & Gasses in Ambient Air

With MARGA, gas and aerosol composition of ambient air can be measured simultaneously and continuously. The analytical part of the instrument consists of two Metrohm Ion Chromatograph systems for anion and cation measurements respectively.

Through a size selective inlet (for example to only measure particles smaller than 10 µm) air is drawn into the MARGA system. It enters a Wet Rotating Denuder (WRD) in which the gasses from the air are absorbed into a thin layer of water. From the WRD the air (now without gasses) flow continues into a Steam Jet Aerosol Collector (SJAC) in which aerosols present are collected in water. The whole MARGA systems runs autonomous, generating aerosol and gas concentrations every hour and only requiring user intervention once per week to supply new solutions. The system can thus be operated in the field in remote places easily.

The sensitivity of the ion chromatographs is sufficient to reach detection limits below 0.1 ug/m3 at a 1 m3/hr air sampling flow. The detection system is continuously calibrated by the use of an internal standard of LiBr, containing anions and cations normally not present in ambient air.

The MARGA is available with 1 or 2 sample boxes, the latter allowing simultaneous sampling of two different aerosol sizes for example PM2.5 and PM10.

Features:

Continuous monitoring with hourly results
Results on the composition of gasses and aerosols
Remote access and data transfer
One week unattended operation
Smart software with security and validation levels
Quality assurance of the measurement with internal standard Ion Chromatography

Ion Chromatography
Ion-exchange chromatography (or ion chromatography) is a process that allows the separation of ions and polar molecules based on the charge properties of the molecules. It can be used for almost any kind of charged molecule including large proteins, small nucleotides and amino acids. It is often used in protein purification, water analysis, and quality control.