Evaluation study of the suitability of instrumentation to measure ambient NH3 concentrations under field conditions

The uncertainties in emissions of ammonia (NH3) in Europe are large, partially due to the difficulty in monitoring of ambient concentrations due to its sticky nature. In the European Monitoring and Evaluation Program (EMEP) the current recommended guidelines to measure NH3 are by coated annular denuders with offline analysis. This method, however, is no longer used in most European countries and each one has taken a different strategy to monitor atmospheric ammonia due to the increase of commercial NH3 monitoring instrumentation available over the last 20 years. In June 2014, a 3 year project funded under the European Metrology Research Programme, “Metrology for Ammonia in Ambient Air” (MetNH3), started with the aim to develop metrological traceability for the measurement of NH3 in air from primary gas mixtures and instrumental standards to field application. This study presents the results from the field intercomparison (15 instruments) which was held in South East Scotland in August 2016 over an intensively managed grassland. The study compared active sampling methods to a meteorological traceable method which was developed during the project with the aim to produce a series of guidelines for ambient NH3 measurements. Preliminary results highlight both the importance of inlets and management of relative humidity in the measurement of ambient NH3 and of the requirement to carry out frequent intercomparison of NH3 instrumentation. Overall, it would be recommended from this study that a WMO-GAW world centre for NH3 would be established and support integration of standards into both routine and research measurements

A new approach to qualifying and quantifying monocyclic aromatic hydrocarbons (MAH ) in workplace atmospheres

At present, monocyclic aromatic hydrocarbons are selectively detected in workplace atmospheres by implementing conventional methods: more specifically, sampling on a medium and conducting a posteriori analysis in the laboratory. The concept of a new realtime analyser, based on CEA/CNRS laboratory research, has been validated by INRS. Work is in progress to design a pre-industrial prototype in the next few years

First French Intercomparison Exercises for Air Quality sensors (EAμC) : results and assessment

International audienc

Discriminating Bacteria With Functionalised Nanoporous Xerogels

International audienceA new colorimetric and easy-to-use solid sensor for the detection of indole-producing bacteria is described. The sensor is a nanoporous matrix with tailored pores doped with a reactant, DMACA. The sensor turns rapidly from transparent to green-blue when exposed to metabolic indole coming from bacteria cultures, both in liquid and gas phases. An example of the discrimination between indole-positive (Eschericia coli) and indole-negative bacteria (Hafnia alvei), two important contaminants in food industry is given