Online CAD/CFD-based design tool to assess ventilation strategies to reduce confined-space entry risk

This article highlights the most salient points from the authors' previously published work on ventilation of manure pits to reduce entry risk. On-farm confined-spaces, such as manure storage pits, often contain toxic and asphyxiating gases including hydrogen sulfide, carbon dioxide, methane and ammonia, as well low oxygen levels. This article describes briefly an innovative approach to manure pit ventilation for human entry into a manure pit that utilizes online software. This software has been turned into an online design aid and represents the culmination of more than a decade-long research and technology development effort at Pennsylvania State University. The online design aid tool results include contaminant gas concentration decay and oxygen replenishments curves inside the manure pit and inside the barns above the manure pits, as well as animated motion pictures of individual gas concentration decay and oxygen replenishment in selected horizontal and vertical cut plots of the manure pits and barns. These results identify ventilation time requirements, manure pit gas evacuation patterns, and animal and personnel evacuation requirements.