Combustible Dust Testing

Laboratory testing to quantify dust explosion and reactivity hazards

Safety Data Sheets

Develop critical safety data for inclusion in SDS documents

Gas and Vapor

Laboratory testing to quantify explosion hazards for vapor and gas mixtures

Classification of hazardous materials subject to shipping and storage regulations
Testing and consulting on the explosion risks associated with devices and processes which use or produce hydrogen
Safety Data Sheets

Develop critical safety data for inclusion in SDS documents

Thermal Stability

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

Adiabatic Calorimetry
Data demonstrate the consequences of process upsets, such as failed equipment or improper procedures, and guide mitigation strategies including Emergency Relief System (ERS) design
Reaction Calorimetry
Data yield heat and gas removal requirements to control the desired process chemistry
Battery Safety

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

Safety Data Sheets

Develop critical safety data for inclusion in SDS documents

Cable Testing
Evaluate electrical cables to demonstrate reliability and identify defects or degradation
Equipment Qualification (EQ)
Testing and analysis to ensure that critical equipment will operate under adverse environmental conditions
Water Hammer
Analysis and testing to identify and prevent unwanted hydraulic pressure transients in process piping
Acoustic Vibration
Identify and eliminate potential sources of unwanted vibration in piping and structural systems
Gas & Air Intrusion
Analysis and testing to identify and prevent intrusion of gas or air in piping systems
ISO/IEC 17025:2017

Fauske & Associates fulfills the requirements of ISO/IEC 17025:2017 in the field of Testing

ISO 9001:2015
Fauske & Associates fulfills the requirements of ISO 9001:2015
Dust Hazards Analysis
Evaluate your process to identify combustible dust hazards and perform dust explosion testing
On-Site Risk Management
On-site safety studies can help identify explosibility and chemical reaction hazards so that appropriate testing, simulations, or calculations are identified to support safe scale up
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 safely handle the effluent discharge from an overpressure event

FATE™ & Facility Modeling

FATE (Facility Flow, Aerosol, Thermal, and Explosion) is a flexible, fast-running code developed and maintained by Fauske and Associates under an ASME NQA-1 compliant QA program.

Mechanical, Piping, and Electrical
Engineering and testing to support safe plant operations and develop solutions to problems in heat transfer, fluid, flow, and electric power systems
Hydrogen Safety
Testing and consulting on the explosion risks associated with devices and processes which use or produce hydrogen
Thermal Hydraulics
Testing and analysis to ensure that critical equipment will operate under adverse environmental conditions
Nuclear Safety
Our Nuclear Services Group is recognized for comprehensive evaluations to help commercial nuclear power plants operate efficiently and stay compliant
Radioactive Waste
Safety analysis to underpin decomissioning process at facilities which have produced or used radioactive nuclear materials
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 and Parts for the DSC/ARC/ARSST/VSP2 Calorimeters

Products and equipment for the process safety or process development laboratory


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


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


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.


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

DIERS Methodology Consulting

DIERS Relief System Design training course

Fauske & Associates (FAI) was the principal research contractor for the Design Institute for Emergency Relief Systems (DIERS), an extensive R & D program sponsored by those 29 companies under the auspices of AIChE and completed in 1985. Company founder, Dr. Hans K. Fauske served as the principal investigator and overall technical leader of the DIERS research project. A primary purpose of that effort was the evaluation of emergency relief vent requirements, including energy and gas release rates for systems under upset conditions and the effect of two-phase flow on the emergency discharge process.

The DIERS program resulted in the development at FAI of the first bench-scale low thermal-inertia adiabatic calorimeter, which was first commercialized as the Vent Sizing Package (VSP). Later improvements led to the VSP2. The Reactive System Screening Tool (RSST) was introduced by FAI in 1989 to provide an easy, inexpensive approach to the DIERS testing method. Subsequent enhancements led to the Advanced RSST (ARSST) in 1999.

FAI uses the DIERS-based VSP2 and ARSST calorimeters to characterize reactive chemical systems and design emergency pressure relief systems. Both instruments provide vent sizing data that are directly applicable to the process scale (directly scalable) which is generally a much easier and more reliable approach than mathematical correction for thermal inertia and kinetic modeling of runaway chemistry.

The purposes of DIERS is to:

  • Reduce the frequency, severity, and consequences of pressure producing accidents
  • Develop new techniques which will improve the design of emergency relief systems

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Relief System Design Training

Fauske & Associates proudly provides training and regularly published articles and blogs on these topics. The popular Relief System Design Course is generally taught over two or three days.

Unlike other emergency vent sizing course, this curriculum includes simplified calculation methods capable of giving safe – but not overly conservative relief system designs, with an emphasis on reactive chemistries and the role of two-phase flow.

Benchmarking of these methods is illustrated with incidents and available plant data. Utilization of methods and equations is demonstrated through practical design examples, covering vapor, gassy, and hybrid systems.  Our FERST software is used to perform detailed calculations using DIERS methodology.

Attendees will participate in group workshops and complete an independent quiz at the end of the course to ensure comprehension of the material. Includes a laboratory session to demonstrate experimental techniques.


Relief System Design Training Course Schedule

Day 1
Day 2
Day 3
  • Introduction to Vent Sizing and Case Study
  • Vent Sizing Fundamentals
  • Codes and Standards Explanation
  • History for DIERS
  • Tow-Phase Flow Considerations
  • Experimental Considerations
  • Vent Sizing Based on All Gas or Vapor Venting
  • Vapor System Vent Sizing
  • Gassy System Vent Sizing
  • Hybrid System Vents Sizing
  • Simplified Two-Phase Flow Methods for Vapor, Hybrid and Gassy Systems
  • Non-Reactive Fire Sizing
  • Stable Relief valve Operation
  • Discharge Coefficient Evaluation
  • Containment and Disposal Considerations
  • Lab Demonstrations



Learning Outcomes
  • Understand up to date DIERS vent sizing methodologies and models, as well as the role of single and two-phase flow in venting behavior
  • Perform vent sizing calculations using the correct models and methodologies
  • Understand and apply adiabatic calorimetry data
  • Apply hands-on techniques and “rules of thumb” to ensure that realistic vessel and vent size conditions are specified


More on the ARSST and the VSP2

The ARSST and VSP2 calorimeters generate reliable adiabatic data which can be used directly for a variety of safety applications including emergency vent sizing, thermal stability, characterization of material compatibility, and chemical reaction kinetics. Test data include adiabatic rates of temperature and pressure rise which, due to the low thermal inertia of the instruments, can be applied directly to process scale conditions for design of pressure relief vents, quench tanks, and determination of process safety parameters.


A fast "minimum best practice" solution that is particularly well suited for energetic gas-generating systems, situations with limited sample quantities, for material that is incompatible with metal, and for quickly screening for unknown adverse reactions. Data are directly applicable to vent sizing and thermal stability analysis. Normally run as an open-cell test, with vaporization suppressed by imposed inert gas overpressure.

Learn more about ARSST by clicking here >


Considered to be "available best practice" this versatile instrument is well-suited for simulating a broad range of abnormal process "upset" conditions to collect directly scalable data suitable for vent sizing. Provides superior mixing and continuous vapor pressure data in a closed cell, ideal for vapor pressure dominated systems.  Scale lends itself to more complex simulations than can be done in the ARSST (for example, metered dosing or addition of small catalyst charges or suspensions/emulsions). Data are directly applicable to vent sizing and thermal stability analysis. Normally run as a closed cell test with active pressure balancing, but often run as an open cell test and can be used for blowdown testing to determine two-phase flow regime.  Can also be used for battery testing.

Learn more about VSP2 by clicking here >


Related Services


DIERS Resources

Advanced Reactive System Screening Tool (ARSST™)
A model of the Dilution of a Forced Two-Phase Chemical Plume in a Horizontal Wind
A Practical Approach to Capacity Certification
ARSST™ Experiments to Evaluate Solvent Compatibility with Stabilized Lithium Metal Power
Determination of Two-Phase Flow Regimes and Pressure Relief Sizing
Emergency Relief System Design for Reactive and Non-Reactive Systems: Extension of the DIERS Methodology

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