Interlock Failures in Process Safety Incidents¶
Process interlocks and safety instrumented functions are engineered barriers designed to prevent runaway or out-of-control states from escalating — their defeat, bypass, or failure has been a recurring theme in CSB findings. Each case below details the interlock-related factors and CSB recommendations.
15 CSB investigations in this database involve interlock as a primary or contributing equipment factor, spanning 1998–2024.
Interlock Failures in Process Safety Incidents (15)¶
| Incident | Date | Industry | Key Hazard |
|---|---|---|---|
| Marathon Martinez Renewable Fuels Fire | 11/19/2023 | Petroleum Refining | Fire, Chemical Release |
| DPC Enterprises Glendale Chlorine Release | 11/17/2003 | Chemical Manufacturing | Toxic Release, Chemical Release |
| DuPont La Porte Facility Toxic Chemical Release | 11/15/2014 | Chemical Manufacturing | Toxic Release, Chemical Release |
| Aghorn Operating Inc. Waterflood Station Hydrogen Sulfide Release | 10/26/2019 | Oil And Gas Production | Hydrogen Sulfide Release, Toxic Release |
| First Chemical Corp. Reactive Chemical Explosion | 10/13/2002 | Chemical Manufacturing | Runaway Reaction, Explosion |
| AirGas Facility Fatal Explosion | 08/28/2016 | Chemical Manufacturing | Explosion, Runaway Reaction |
| Bayer CropScience Pesticide Waste Tank Explosion | 08/28/2008 | Chemical Manufacturing | Runaway Reaction, Explosion |
| Millard Refrigerated Services Ammonia Release | 08/23/2010 | Food Processing | Ammonia Release, Chemical Release |
| Sterigenics Ethylene Oxide Explosion | 08/19/2004 | Chemical Manufacturing | Explosion, Fire |
| Dow Louisiana Operations Explosions | 07/14/2023 | Chemical Manufacturing | Explosion, Fire |
| Kuraray Pasadena Release and Fire | 05/19/2018 | Chemical Manufacturing | Chemical Release, Fire |
| Formosa Plastics Vinyl Chloride Explosion | 04/23/2004 | Chemical Manufacturing | Explosion, Fire |
| Yenkin-Majestic Resin Plant Vapor Cloud Explosion and Fire | 04/08/2021 | Chemical Manufacturing | Vapor Cloud Explosion, Explosion |
| Packaging Corporation of America Hot Work Explosion | 02/08/2017 | Paper And Pulp | Explosion, Fire |
| Foundation Food Group Fatal Chemical Release | 01/28/2021 | Food Processing | Chemical Release, Asphyxiation |
Related Hazard Types¶
Chemical Release · Fire · Explosion · Toxic Release · Overpressure
Related Equipment¶
Valve Failures in Process Plant Incidents · Gas Detector Failures and Toxic Release Incidents · Pump Failures and Process Safety Incidents · Relief Valve Failures and Overpressure Events · Pipeline Ruptures, Leaks, and Fires · Storage Tank Fires and Explosions
Data sourced from CSB.gov public investigation reports. This site is an independent project not affiliated with the U.S. CSB.