H1 (formerly D1) Environment Agency Stack Height Calculation Guidance
H1 was the Environment Agencies software tool to calculate the stack height for satisfactory dispersion of the substances handled.
NOTE – It was WITHDRAWN in 2016 and is not their current guidance. However, it is still a useful method for calculating Effective Stack Heights and therefore actual physical stack heights required. It is understood (2020) that HSE in UK will still accept this D1 guidance when calculating required stack heights.
Copy of the (withdrawn) D1 guide can be downloaded here:- Env Agency D1
Now if you are looking at the correct dispersion modelling stack heights to be used for Environmental emissions reasons – you need to visit the URL below pointing to the Environment Agency’s website for more information on Dispersion Risk Assessment and Dispersion Modelling:-