Project activities 

The project is grouped in 4 technical workpackages, plus one creating impact and one management and coordination workpackage. The technical WPs are set up as the following:

  • WP_1: Calibration gases for existing air quality directive pollutants at limit values

  • WP_2: Zero gas standards

  • WP_3: Traceability for the measurement of (S)VOC in indoor air and constant emitting materials for quality assurance purposes

  • WP_4: Micro-sensors for ambient and indoor air

Project objectives 

The objectives of WP_1 are:

  • To revisit static and dynamic dilution methods coupled to generation techniques for the preparation of high accurate calibration gases (and low uncertainties) for reactive air quality directive pollutants, namely nitrogen oxides and sulphur dioxide, at and beyond the limit values set in the Air Quality Directive (2008/50/EC)

  • To harmonize the reviewed generation methods by comparison with existing or new developed travelling standards to obtain a degree of comparability (and uncertainty) among them


The objectives of WP_2 are:

  • To develop a measurement approach with existing and novel optical techniques for the single and simultaneous assessment of the impurities of zero gases used in the measurement of reactive gases (nitrogen oxides and sulphur dioxide)

  • To validate concentration values (of impurities) assigned by optical techniques (absolute method) by comparison with the standard addition method used in purity determination realized with classical detection techniques

  • To investigate the adsorption effect during sampling and measuring reactive gases at trace levels using ammonia as case study

  • To test cleaning systems with the developed assessment approach in order to obtain zero gas standards to be used for the validation of a certification protocol for zero gas


The objectives of WP_3 are:

  • To develop reference measurement methods and materials for the measurement of a selected list of volatile organic compounds with special focus on the challenging semi-volatiles at indoor air concentration levels

  • To produce and test a constant VOC emitting material for the quality control of emission testing chambers




The objectives of WP_4 are:

  • To develop a new highly sensitive and selective NO2 sensor using a promising technology: graphene sensors

  • To develop calibration procedures for micro-sensors and a testing protocol to evaluate their performances

  • To run an extended programme validation for graphene and commercially available sensors for one or two gaseous compounds, likely NO2 and O3, for which limit values exceeding the European Directive keep on being registered

  • To group graphene and/or commercially available sensors and common meteorological parameters (temperature, relative humidity etc.) into a clustered system able to monitor as many as possible air pollutants regulated by the Air Quality Directive 2008/50/EC