Combustible Dust Testing

Laboratory testing to quantify dust explosion & reactivity hazards

Flammable Gas & Vapor Testing

Laboratory testing to quantify explosion hazards for vapor and gas mixtures

Chemical Reactivity Testing

Laboratory testing to quantify reactive chemical hazards, including the possibility of material incompatibility, instability, and runaway chemical reactions

DIERS Methodology

Design emergency pressure relief systems to mitigate the consequences of unwanted chemical reactivity and account for two-phase flow using the right tools and methods

Deflagrations (Dust/Vapor/Gas)

Properly size pressure relief vents to protect your processes from dust, vapor, and gas explosions

Effluent Handling

Pressure relief sizing is just the first step and it is critical to safety handle the effluent discharge from an overpressure event

Thermal Stability

Safe storage or processing requires an understanding of the possible hazards associated with sensitivity to variations in temperature

UN-DOT

Classification of hazardous materials subject to shipping and storage regulations

Safety Data Sheets

Develop critical safety data for inclusion in SDS documents

Biological

Model transport of airborne virus aerosols to guide safe operations and ventilation upgrades

Radioactive

Model transport of contamination for source term and leak path factor analysis

Fire Analysis

Model transport of heat and smoke for fire analysis

Flammable or Toxic Gas

transport of flammable or toxic gas during a process upset

OSS consulting, adiabatic & reaction calorimetry and consulting

Onsite safety studies can help identify explosibility and chemical reaction hazards so that appropriate testing, simulations, or calculations are identified to support safe scale up

Mechanical, Piping, and Electrical

Engineering and testing to support safe plant operations and develop solutions to problems in heat transfer, fluid flow, electric power systems

Battery Safety

Testing to support safe design of batteries and electrical power backup facilities particularly to satisfy UL9540a ed.4

Hydrogen Safety

Testing and consulting on the explosion risks associated with devices and processes which use or produce hydrogen

Spent Fuel

Safety analysis for packaging, transport, and storage of spent nuclear fuel

Decommissioning, Decontamination and Remediation (DD&R)

Safety analysis to underpin decommissioning process at facilities which have produced or used radioactive nuclear materials

Laboratory Testing & Software Capabilities

Bespoke testing and modeling services to validate analysis of DD&R processes

Nuclear Overview

Our Nuclear Services Group is recognized for comprehensive evaluations to help commercial nuclear power plants operate efficiently and stay compliant.

Severe Accident Analysis and Risk Assessment

Expert analysis of possible risk and consequences from nuclear plant accidents

Thermal Hydraulics

Testing and analysis to ensure that critical equipment will operate under adverse environmental conditions

Environmental Qualification (EQ) and Equipment Survivability (ES)

Testing and analysis to ensure that critical equipment will operate under adverse environmental conditions

Laboratory Testing & Software Capabilities

Testing and modeling services to support resolution of emergent safety issues at a power plant

Adiabatic safety calorimeters (ARSST and VSP2)

Low thermal inertial adiabatic calorimeters specially designed to provide directly scalable data that are critical to safe process design

Other Lab Equipment (DSC/ARC supplies, CPA, C80, Super Stirrer)

Products and equipment for the process safety or process development laboratory

FERST

Software for emergency relief system design to ensure safe processing of reactive chemicals, including consideration of two-phase flow and runaway chemical reactions

FATE

Facility modeling software mechanistically tracks transport of heat, gasses, vapors, and aerosols for safety analysis of multi-room facilities

Blog

Our highly experienced team keeps you up-to-date on the latest process safety developments.

Process Safety Newsletter

Stay informed with our quarterly Process Safety Newsletters sharing topical articles and practical advice.

Resources

With over 40 years of industry expertise, we have a wealth of process safety knowledge to share.

Recent Posts

An Explosion Accident Case Review and Investigation: PSM

Posted by The Fauske Team on 04.16.14

By Amy Theis, Director of Risk Management Services and Sara Peters, Marketing Specialist, Fauske & Associates, LLC

process safety evaluationA deflagration incident (explosion) occurred during the cleaning procedure of a pan coater that was used in an encapsulation process where a latex coating was spray-applied intermittently to small beads of an oxidizing chemical. This case study describes the incident, and investigation including reviewing testing results, providing process hazard evaluation (PHA) and outlining benefits of process safety management (PSM) systems and best practices for fire and explosion protection due to combustible dust.                             

Incident Description

The company employed four pan coaters in series. Each had an exhaust tube connected to a common duct leading to a wet dust collector as well as an air connection utilizing a common air supply. On the day of the incident, two of the four pan coaters required cleaning due to a layer of latex and chemical that adhered to the inside of the pan. The cleaning process presented a challenge since the pan geometry made it difficult to clean, and the well-cured coating adhering to the pan proved stubbornly resistant to scraping, chipping and other physical means of attack.

In frustration at the difficulty of removing the residual coating, an employee began to chisel at it forcefully with a large and heavy steel pry bar.  The repeated blows from the pry bar caused a roughly 2 inch diameter area on the exterior of the pan to glow red from heat. Two employees then observed the red spot rapidly grow to approximately 6 to 8 inches in size. At this time, they chose to evacuate the room. Approximately 20 seconds later an explosion occurred.

There was no explosion isolation in place between the pan coaters to prevent deflagration propagation between the interconnected pieces of equipment. Such isolation is recommended by NFPA 654, Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids. As a result the deflagration pressure wave and fire generated from the incident spread out of the pan coater mouth and through the exhaust ductwork to the other interconnected coaters.  Due to overpressure, the exhaust system ductwork ruptured.  Residual coating material in the other dirty pan coaters also ignited.  Thankfully, no personnel were injured.

Incident Testing Results

In an effort to characterize the events that led to the incident, several Differential Scanning Calorimetry (DSC) tests were performed using several ratios of coating to oxidizer material. The most energetic sample was then tested in various forms for drop weight impact (BAM Fallhammer) testing. It should be noted that samples 3 and 6 were wet material.

 drop impact sensitivity testing   differential scanning calorimetry tests

Integrated Solution

Though this process was not covered by OSHA Process Safety Management (PSM), several elements of PSM were utilized to reduce risk, improve methods, review management systems and ensure that personnel were aware of critical tasks.

Incident Investigation

  • Root cause analysis identified impact sensitivity, lack of appropriate procedures and inappropriate cleaning tools

Process Safety Information (PSI)

  • Thermal stability and impact sensitivity were not known
  • Cleaning procedures were not available/reviewed during the PHA 

Process Hazard Analysis (PHA)

  • PHA was performed, however PSI was not complete
  • Appropriate personnel were not involved
  • Change in raw material was not considered regarding the impact on the process

Mechanical Integrity (MI)

  • Usage and wear of equipment was reviewed to determine appropriate maintenance and replacement schedules
  • Reviewed MI program with employees to define expectations and unacceptable repair methods

Procedures

  • Job Hazard Analyses (JHAs) were conducted with employees to identify hazards associated with operations cleaning and maintenance tasks associated with equipment used for this process

Training

  • Operators were trained regarding updated procedures, as well as the functionality of the MI and Management of Change (MOC) programs and how to access these programs

Facility Siting & Human Factors                          

  • New production facility was designed incorporating industry best practices

 

Conclusion

Updated process safety information was used to reduce risks associated with this process:

  1. Several alternative cleaning strategies were investigated and a non-impact method was selected.

  2. Spray methodology was changed to reduce the accumulation of coating on the inside wall of the pan coaters by improving the angle of the spray and reducing the timing of the spray.

  3. Employee involvement in the review of procedures was critical to understand current practices, evaluate potential alternatives and obtain employee support for the procedure changes that followed

 
Process Safety Management (PSM) Overview

Topics: Combustible dust, NFPA 654, combustible hazard, OSHA, PSM, process safety management, process safety, process hazards analysis, explosion protection, process hazards, BAM fallhammer, BAM test, DSC, Differential Scanning Calorimetry, explosion accident, deflagration, jobs hazards analysis

cta-bg.jpg

Is My Dust Combustible?

A Flowchart To Help You Decide
Download Now