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.

Adiabatic Calorimetry & Relief Vent Sizing

VSP2 & Relief Valve SizingBackground

Adiabatic calorimeter testing provides data for relief system design, safe scale-up of chemical processes, and changes to process recipes.  Safe process design requires knowledge of chemical reaction rates, character and energy release - all of which can be obtained from a low phi-factor adiabatic calorimeter such as the VSP2TM (Vent Sizing Package 2) or ARSSTTM (Advanced Reactive System Screening Tool).

Benefits

The VSP2 TM  and the ARSST TM provide thermal data required for safe scale-up of chemical processes and changes to process recipes. A variety of process upset conditions can be tested to quantify hazards identified by a PHA or HAZOP study. The low phi-factor (or thermal inertia) allows the heat and gas generation rates to be measured and directly applied to the process scale, which leads to appropriately designed emergency relief systems.

Process Safety

DIERS

Fauske & Associates, LLC (FAI) was the principal research contractor for the Design Institute for Emergency Relief Systems (DIERS), an extensive R&D program sponsored by 29 companies under the auspices of AIChE and completed in 1985.  Company founder, Dr. Hans K. Fauske served as the principal investigator and overall leader of the DIERS research project.  A primary purpose of that effort was 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 of a bench scale low thermal inertia adiabatic calorimeter, which was first commercialized as the Vent Sizing Package (VSPTM). Later improvements led to the VSP2TM. The Reactive System Screening Tool (RSST TM) was introduced by FAI in 1989 to provide an easy, inexpensive approach to the DIERS testing method. Recent enhancements led to the Advanced RSST (ARSSTTM) in 1999. FAI uses the DIERS-based VSP2TM and ARSSTTM calorimeters to characterize chemical systems and design emergency pressure relief systems. Both instruments provide vent sizing data that are directly applicable to the process scale.

ARSST™ (Advanced Reactive System Screening Tool)

ARSSTBackground

Fauske & Associates, LLC's (FAI) Advanced Reactive System Screening ToolTM (ARSST) is a low thermal inertia calorimeter used to obtain critical upset process design data.  FAI offers the ARSST along with options for customization such as a high-pressure vessel and flow regime detector, as well as commonly used items such as test cells, heaters, glands and thermocouples. At FAI, we not only utilize the ARSSTTM in our fully equipped hazards laboratory but we also manufacture and sell the calorimeter for use by our clients.

The ARSSTTM is based on DIERS two-phase methodology which is recognized by OSHA as an example of good engineering practice. This easy-to-use device is also capable of generating low phi-factor data for DIERS vent sizing and is an excellent tool for industry as well as any university engineering lab for research or unit operation studies.

ARSSTTM tests are used to model such upset scenarios as loss of cooling, loss of stirring, mischarge of reagents, mass-loaded upset, batch contamination and fire exposure heating.  This easy to use and cost-effective calorimeter can quickly and safely identify potential reactive chemical hazards in the process industry.  ARSSTTM data yields critical experimental knowledge of the rates of temperature and pressure rise during a runaway reaction, thereby providing reliable energy and gas release rates which can be applied directly to full scale process conditions. 

The ARSSTTM typically utilizes a sample size of 5-10 grams in a lightweight glass test cell with a volume of approximately 10 ml.  The test cell is outfitted with a belt heater (used to heat the sample through a preprogrammed temperature scan) and then installed in 350 ml containment vessel.  Tests are typically run using open test cell methodology.  In this test configuration, the test cell is vented to the containment vessel.  Volatilization of the test sample is prevented by imposing an inert  backpressure on the containment vessel.

Benefits

The ARSSTTM enables users to quickly obtain reliable adiabatic data which can be used for a variety of safety applications including characterization of material compatibility, thermal stability and reaction chemistry.  Test data includes adiabatic rates of temperature and pressure change which, due to the low thermal inertia, can be directly applied to process scale to determine relief vent sizes, quench tank designs and other relief system design parameters related to process safety management.

Features

  • User friendly
  • Easy setup for fast test turnaround
  • Quickly screen new and existing processes for thermal hazards
  • Scanning and isothermal modes
  • Reliable results for thermal hazard assessment
  • Open or closed cell testing (obtain vapor pressure data from closed cell testing)
  • Small sample size
  • Lightweight glass test cell with good mixing
  • Compatible with Flow Regime Detector (FRED) equipment for vent sizing applications (FRED distinguishes between foamy and non-foamy behavior)

ApplicationsARSST

  • Obtain complete chemical systems data:
    -    Critical temperature
    -    Kinetic parameters
  • Estimate process safety parameters including:
    -    Onset temperature
    -    Temperature & pressure rise rates
    -    Adiabatic temperature rise
    -    Heat of reaction and mixing
    -    Tempering temperature
    -    Time to maximum rate (tmr)
    -    Self-accelerating decomposition temperature (SADT)
  • Vent sizing
  • Emergency relief system design
  • Accommodates handling of energetics and pyrotechnics

Vent Sizing Package 2 (VSP2™)

BackgroundVSP2

Fauske & Associates, LLC's (FAI) Vent Sizing Package 2™ (VSP2™) is a low thermal inertia adiabatic calorimeter used for process hazard characterization that utilizes state-of-the-art DIERS technology to obtain critical upset process design data.  It is the commercial version of the original DIERS bench scale apparatus. At FAI, we not only utilize the VSP2TM in our fully equipped hazards laboratory but we also manufacture and sell the calorimeter for use by our clients.

Its versatile and innovative design allows the VSP2TM to simulate upset (abnormal) conditions which might lead to a runaway chemical reaction (e.g. loss of cooling, loss of stirring, mischarge of reagents, mass-loaded upset, batch contamination, fire exposure heating, etc).  Resulting temperature and pressure rise rates are directly scalable since it is a low thermal inertia (phi-factor) apparatus. 

Benefit

The VSP2TM utilizes established DIERS technology to identify and quantify process safety hazards so they can be prevented or accommodated by process design.  

Test data includes adiabatic rates of temperature and pressure change which, due to the low thermal inertia, can be directly applied to process scale to determine relief vent sizes, quench tank designs and other relief system design parameters related to process safety management.  Adiabatic data obtained with the VSP2TM can be used to characterize reactive chemical and consequences that could occur due to process upset conditions.

Features

The versatile configurations offered by the VSP2TM design directly simulates process conditions including:

  • Loss of cooling or agitation
  • Accumulation or mischarge of reactants
  • Contamination of batch
  • Thermally initiated decomposition
  • Resident incubation time
  • In-situ liquid/gas dosing or sampling

Applications

Use of the VSP2TM can help users obtain complete chemical system data such as:

  • Low thermal inertia testing allows data to be directly applied to process scale
  • Temperature and pressure rise rates applicable to relief system design "Based on DIERS two-phase flow technology, recognized by OSHA as an example of “good engineering practice”
  • Many testing configurations
    -    Solids, liquids or two phase mixtures
    -    Closed or open (vented) tests
    -    Scaled blowdown simulation
    -    Test cells are available in 304 & 316 SS, Hastelloy C, Titanium and glass

VSP2

  • Accurate adiabatic data 
    -    Onset temperature
    -    Total adiabatic temperature rise (ΔTad)
    -    Heat of reaction or mixing
    -    Vapor pressure data
    -    Time to maximum rate (tmr)
    -    Self-accelerating decomposition temperature (SADT)
  • Relief valve sizing
  • Quench tank design
  • Effluent handling
  • Critical temperature
  • Effect of two-phase flow

FAI has also created the PrEVent software to allow users to implement practical emergency vent sizing using industry recognized methodology.  It applies DIERs methodology (including the Leung-Omega and Fauske methods) for reactive chemistry and API 520/2000 or NFPA 30 for non-reactive systems.

Flow Regime Detector (FRED™)

Background

FREDKnowledge of the prevailing flow regime during emergency venting of a runaway chemical reaction is essential in order to estimate a realistic but safe relief system design.  It is not possible to predict the foaming behavior from physical properties alone. Since flow regime characterization methods for actual runaway conditions are not available, the general DIERS practice has been to design for “foamy” conditions, i.e. homogeneous vessel conditions, which is a conservative assumption.  Considering that the occurrence of “foamy” versus “non-foamy” conditions is very sensitive to impurities, minute changes in concentration levels and other factors, the flow regime characterization needs to be performed under actual runaway conditions coinciding with the relief venting process. 

The Flow Regime Detector sensor is comprised of a small immersion heater and an attached thermocouple that is positioned in the upper free board space of the test cell.  (For Flow Regime determination tests, the test cell is only about 1/3 full).

Prior to externally heating the chemical sample itself, power is supplied via an auxiliary control box to the internal heating coil to establish an elevated (baseline) sensor temperature.  This baseline temperature should be well above the anticipated boiling (tempering) temperature of the sample.  The detector operates on the principle that if the flow regime following the onset of boiling is non-foamy, then the detector thermocouple (TC2) will continue to measure a temperature well in excess of the sample temperature (TC1). 

Benefits

Fauske & Associates, LLC (FAI) offers a Flow Regime Detector (FRED™) for use in conjunction with the ARSSTTM and VSP2TM  calorimeters to distinguish between foamy and on-foamy runaway reactions.  Relief systems for non-foamy systems may be more realistically designed by treating the two-phase discharge flow as churn-turbulent rather than homogeneous.

Features

  • Easy to use and interpret results
  • Compatible with ARSSTTM and VSP2TM

PrEVent™ - Practical Emergency Vent Sizing Software

Background

PrEVent Fauske & Associates, LLC (FAI) created its PrEVent™ software to allow users to implement practical emergency vent sizing designs utilizing industry recognized methodology including the Leung Omega method, Fauske Gas/Vapor method and Fauske General Screening method.  The software applies DIERS methodology for reactive chemistry and API 520/2000 or NFPA 30 for non-reactive systems. This methodology was designed in conjunction with the VSP2TM and is a great companion to any low phi factor adiabatic calorimeter. 

PrEVent™ handles gassy, hybrid and vapor systems for reactive scenarios and can also accommodate deflagration venting as well as fire load sizing. The modern user interface features clear navigation, logical tabs and intuitive drop down menus that take advantage of cutting edge Windows programming techniques for a crisp seamless user experience. It is available as a standalone Windows application, or as a Silverlight 4 based web application supporting a wide-range of platforms including all major browsers on both Mac OS X and Windows – Internet Explorer 6, 7, 8, Firefox 2 and 3, Safari 3 and 4 and Google Chrome.

Benefits

The streamlined interface allows users to make changes to input values "on the fly" and see the results updated immediately. This is convenient for parametric studies, such as varying the batch size to see how much reactant will "fit" within a particular vessel/relief installation. Input parameters, including vessel geometry, reactant properties and adiabatic reaction rates at venting, are conveniently entered using simple drop down windows and saved for later use.

It is the latest version in a line of vent sizing code solutions designed to be quick and easy to use, requiring many fewer physical properties than other programs. 

Solutions/Expertise/Training

Fauske & Associates, LLC (FAI) has been the industry leader in adiabatic calorimetry since the concept of DIERS testing was first introduced in 1985. 

Our team is happy to help train your staff in the understanding of technical issues, process safety programs or audits, regulations and more.  We perform process safety audits as part of a comprehensive hazards analysis and can work with you to make sure your staff is supplied with skills training needs in many ways including: 

Level I - Gap Analysis
Level II - training & consulting
Level III - Program Development and Implementation

Partial List of Services Offered:
• Reviews and upgrades of all your safety process systems and regulatory requirements
• VPP Consulting
• Audits, reviews, and upgrades of all your Operating, Safety, and Maintenance Procedures
• Training program evaluations for both completeness and effectiveness (from technical skills to professional development) and upgrades where
needed
• Reviews and upgrades of your program elements such as Employee Participation and Process Safety Information for effectiveness and completeness
• Work process effectiveness evaluations and upgrades
• Overall organizational development (e.g., motivation, work processes)
• Stress reduction
• Evaluations of the effectiveness of communication

We design, custom develop and deliver any site specific training materials needed by your organization. Our Consultants, Engineers and Technical Specialists are available to deliver the classroom, lab or on-the-job training your staff needs. In addition, we will assist with the identification and procurement of commercially available training materials where available.

CTA_Strip_Bg-1.jpg

FAI used adiabatic calorimetry and a new thermal analysis technique to obtain decomposition data

Download Case Study

Resources