CSB Investigation — Reactive Chemical Explosion
Catalyst Systems Inc. Reactive Chemical Explosion
Catalyst Systems Inc.
📍 Gnadenhutten, OH
Incident Date: January 2, 2003  |  CSB Report Released: October 2003
0
Fatalities
1
Injuries (Minor)
4
CSB Recommendations
Benzoyl Peroxide
Chemical / Hazard
📋 Incident Summary

On January 2, 2003, a vacuum dryer containing approximately 200 pounds of 75% benzoyl peroxide (BPO) explosively decomposed at the Catalyst Systems Inc. production facility in Gnadenhutten, Ohio. Employees were drying granular BPO to increase its concentration from 75% to 98%. The explosion damaged the BPO processing building. One employee received a minor injury while evacuating.

Benzoyl peroxide is a well-known reactive chemical that can undergo exothermic decomposition if overheated or contaminated. The vacuum dryer used in the drying process had been purchased second-hand with no wiring diagram, engineering drawings, or documentation of its heating system characteristics. No written operating procedures for drying BPO had been developed — workers operated the dryer based on verbal instructions only.

The CSB investigation found that Catalyst Systems had no program to formally evaluate the reactive hazards of its processes. The decision to use a second-hand dryer of unknown characteristics for a reactive chemical drying operation was made without any engineering or hazard review. The case illustrates how a well-known industrial hazard can cause an incident when the organization handling the chemical has no process for recognizing or managing reactive risks.

🔎 Key Findings
Finding 1
BPO Decomposition Hazard Not Formally Recognized
The thermal decomposition hazard of benzoyl peroxide during vacuum drying — a well-documented industrial hazard — was never formally evaluated. No reactive hazard characterization had been performed for the BPO drying process.
Finding 2
Second-Hand Dryer with No Documentation
The vacuum dryer was purchased second-hand with no engineering drawings, wiring diagrams, or documentation. The heating characteristics and thermal control capability were unknown.
Finding 3
No Written Operating Procedures
No written procedures for drying BPO had been developed. All operational guidance was provided verbally, with no documented temperature limits, monitoring requirements, or emergency steps.
Finding 4
No Process Hazard Analysis
No PHA or reactive hazard screening had been performed on the BPO drying process. The reactive hazard of drying BPO in a vacuum dryer was never systematically identified.
Finding 5
BPO Decomposition is a Well-Known Industrial Hazard
Benzoyl peroxide is extensively documented as a heat-sensitive reactive chemical with a low onset decomposition temperature. The hazard class was well known; the facility lacked the management systems to recognize it.
Finding 6
No Management Systems for Reactive Hazard Control
Catalyst Systems had no formal program to evaluate reactive chemical hazards, no written procedures for handling them, and no engineering review process for selecting and qualifying process equipment.
🔍 Root Causes
1
Reactive Hazard Not Characterized or Managed
The fundamental failure was the absence of any management system to recognize, characterize, and control the reactive hazard of drying benzoyl peroxide.
2
Process Equipment Used Without Engineering Review
The second-hand vacuum dryer was placed into service for a reactive chemical operation without any engineering review, equipment qualification, or verification of heating control capability.
3
No Written Procedures for Reactive Chemical Operation
Verbal instructions alone are not adequate for reactive chemical operations. Written procedures with defined temperature limits, monitoring requirements, and emergency steps are a minimum requirement.
4
No PHA for Reactive Process
The absence of a process hazard analysis meant there was no systematic mechanism to identify the BPO decomposition risk before it caused an explosion.
☑ CSB Recommendations
→ Catalyst Systems Inc.
Implement a reactive hazard screening program to evaluate all chemicals used or produced at the facility for reactive hazard potential before beginning new processes or changing existing ones.
→ Catalyst Systems Inc.
Develop written operating procedures for all reactive chemical operations, including BPO drying, that specify temperature limits, monitoring requirements, and emergency response steps.
→ Catalyst Systems Inc.
Conduct engineering review and qualification of all process equipment used for reactive chemical operations before putting new or second-hand equipment into hazardous service.
→ AIChE / CCPS / Chemical Industry
Expand outreach on reactive chemical hazard characterization, specifically targeting small and mid-size chemical manufacturers who may not have in-house reactive hazard expertise.
💡 Lessons Learned
⚠ Benzoyl peroxide and other organic peroxides are reactive chemicals with well-documented decomposition hazards. Not knowing a well-known hazard is a management failure, not an acceptable gap.
⚠ Second-hand process equipment used for reactive chemical operations must be fully characterized and engineering-qualified before use. Unknown heating characteristics plus reactive chemical equal unknown risk.
⚠ Written procedures are not bureaucratic overhead — for reactive chemical operations they are the documented body of knowledge about how to do the job safely. Verbal instructions are not a substitute.
⚠ Process hazard analysis for reactive chemical operations is not optional. It is the mechanism by which an organization systematically identifies its worst-case scenarios before they become incidents.
⚠ Small and mid-size chemical manufacturers face the same reactive hazards as large chemical companies. The absence of in-house reactive hazard expertise does not reduce the hazard — it requires obtaining outside expertise.
PSM Elements: PSI · PHA · SOP · MI
🔨 Safety Meeting Toolbox Talk
Topic: Reactive Chemical Hazard Characterization & Small Manufacturer Safety
💬Does our facility use, produce, or handle any organic peroxides, unstable compounds, or other reactive chemicals? Have we conducted reactive hazard screening for each?
💬Have we developed written operating procedures — not just verbal instructions — for all reactive chemical operations, with documented temperature limits and emergency steps?
💬When new or second-hand equipment is introduced for reactive chemical processing, is an engineering review and qualification performed before the equipment is placed in hazardous service?
💬Has our facility conducted a process hazard analysis for all operations involving reactive chemicals, even if those operations are not subject to OSHA PSM requirements?
💬Are all temperature limits for reactive chemical drying, distillation, or reaction operations based on documented reactive hazard characterization data?
✎ Team Action Items
✓Identify all reactive chemicals in your facility — peroxides, nitro compounds, unstable isomers, polymerizing monomers — and confirm a reactive hazard screening has been conducted for each
✓Pull operating procedures for reactive chemical processes and confirm they include documented temperature limits based on reactive hazard data, not just general operating ranges
✓Identify any second-hand or non-standard equipment used for reactive chemical operations and verify engineering qualification documentation exists
✓Confirm a PHA or equivalent hazard review has been performed for all reactive chemical operations in your area, regardless of OSHA PSM threshold status
🔗 PSM Failures Behind This Incident

This incident traced to breakdowns across 4 PSM elements (PSI · PHA · SOP · MI). Each represents a documented gap that process safety documentation and consulting can close before a similar event occurs at your facility.

Process Safety Information (PSI)
Accurate, complete Process Safety Information is the foundation every other PSM element depends on. When PSI is missing or wrong — chemistry data, equipment specs, P&IDs — the entire hazard analysis is built on a flawed base.
Supporting documents in our library →
Process Hazard Analysis (PHA)
A structured PHA or HAZOP study exists to identify exactly these scenarios before they occur. When PHA is absent, superficial, or overdue for revalidation, hazards operate unseen until they kill someone.
Supporting documents in our library →
Operating Procedures (SOPs)
Operators cannot reliably hold safe operating limits without clear, current, enforced procedures. Deviation from acceptable operating conditions — a root cause here — is a direct consequence of SOP failure.
Supporting documents in our library →
Mechanical Integrity (MI)
Equipment must be designed, inspected, and maintained to operate safely in its intended service. Mechanical integrity failures — degraded equipment, missed inspections, deferred repairs — contributed to loss of containment here.
Supporting documents in our library →
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