QAL2 stands for Quality Assurance Level 2, and it is a term commonly used in the context of air quality monitoring and the operation of Continuous Emissions Monitoring Systems (CEMS). The concept of QAL2 is part of a framework established to ensure the reliability and accuracy of data collected from air quality monitoring instruments, particularly those used to measure emissions from industrial sources.

The European Union, through the European standard EN 14181, and other regulatory bodies, has defined a set of Quality Assurance (QA) levels for CEMS, and QAL2 is one of these levels. The QA levels are hierarchical and represent different levels of quality control measures. Here’s a brief overview of the QA levels:

The goal of the QAL2 process is to maintain the accuracy and reliability of emissions data, which is crucial for regulatory compliance and environmental protection. It helps ensure that the continuous monitoring systems provide trustworthy information on the emissions of pollutants from industrial sources.