Accidental Hazardous Release Modeling

In addition to developing toxic dispersion, fire, and explosion modeling software, BREEZE Software also has extensive experience managing and conducting accidental hazardous release modeling projects. The BREEZE Team has a thorough understanding of source term calculation methods and impact analysis models in order to evaluate potential hazards due to accidental release of chemicals under various situations. This thorough understanding of the models in combination with our expertise with U.S. and international regulatory requirements enables BREEZE to complete accidental hazardous release assessments in an efficient and cost-effective manner.

Common accidental hazardous release modeling projects include:

• U.S. EPA Risk Management Program (RMP) Off-site Consequence Analysis (OCA) assessments
• Facility design and safety improvement purposes
• Real-time assessment of hazards in emergency situations
• Reconstruction of a past incident for investigative or litigation purposes

Project Snapshot: Hazardous Release Modeling

The objective was to evaluate the potential effects of a CO₂ release from an orifice in a pressurized pipeline to estimate the area in which a harmful concentration of CO₂ could occur during an accidental release. Eight scenarios were evaluated, covering two different release orifice sizes, two different wind speed conditions, and two different ambient temperatures. To model these eight scenarios, the client provided BREEZE with the CO₂ properties used to calculate the released CO₂ density, which was determined to be denser than air. As a result, the SLAB model, incorporated into BREEZE Incident Analyst, was selected to perform the dispersion modeling analysis. Incident Analyst was used to input values into SLAB, run SLAB, and then analyze the results in a tabular format. The levels of concern used for the modeling analyses were the 5,000 ppm OSHA 8-hour time weighted average permissible exposure limit standard (TWA PEL) and the 40,000 ppm NIOSH immediately dangerous to life and health standard (IDLH). The endpoint distance from the release point to each threshold concentration was modeled for all eight scenarios. Results were presented to the client in graphical and tabular formats.