An EU standard (EN) on Model Quality Objectives

Service Contract Study to Support the performance assessment and adoption of a European standard (EN) for modelling quality objectives for assessment purposes in ambient air

The European Ambient Air Quality Directive (AAQD) sets binding limits on key air pollutants to protect human health and the environment. Compliance has traditionally relied on monitoring stations providing precise, real-time data. These measurements are crucial for tracking trends, identifying pollution hotspots and informing mitigation strategies.

Air quality modelling is becoming increasingly important in the assessment of air quality in the EU, complementing and enhancing measurement networks. Models offer predictive insights and spatial coverage that measurements alone cannot provide, predicting future pollution levels and evaluating policy interventions. They help decision-makers anticipate pollution episodes, understand causes and explore “what-if” scenarios, which real-time measurements cannot achieve alone. Modelling is essential for policy compliance, especially where direct measurement is impractical or costly.

For air quality models to be fully accepted under the AAQD, common standards and transparent methodologies are needed to ensure comparable and reliable results across Europe. Currently, there is no European standard for Modelling Quality Objectives (MQO). The European Commission plans to request the European Committee for Standardisation (CEN) to develop such a standard.

This project aims to support the performance assessment and establishment of a European standard (EN) on Modelling Quality Objectives for ambient air assessment. This involves pre-normative activities to ensure the standard is well-founded, comprehensive and aligned with existing needs and frameworks.

VITO’s air quality modelling team is collaborating with experts from Ricardo (the Netherlands), RIVM (the Netherlands), INERIS (France) and IVU Umwelt (Germany) to deliver this service contract for the European Commission.