None of the screening tools available for stacks (e.g. the HMIP D1 method or the LAQM Emissions Screening Tools) are applicable to my installation due to a low exit velocity, or buildings taller than the stack. How do I assess its air quality impact?
Low exit velocities can be handled by advanced dispersion models, and even by screening models, such as ADMS-Screen. Complex and tall buildings close to short stacks are a challenge for any predictive technique, and may require sensitivity analyses using more than one dispersion model, or Computational Fluid Dynamics (CFD) if the potential impacts are contentious e.g. in an Air Quality Management Area (AQMA) or very close to sensitive receptors.
Should local authorities require further details relating to assessing air quality impacts of emissions from stacks, then please contact the LAQM Helpdesk.