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


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Published July 22, 2013

5 Steps to Understanding Combustible Dust Electrical Classification

Layer Ignition Test (LIT) Chemical Risk Management and Nuclear Plant Safety   Layer Ignition Test (LIT)

Important Differences between NFPA 499 and OSHA Requirements

When dealing with electrical area classification for combustible dusts, there are several different approaches suggested by scientific and regulatory bodies such as the NFPA, OSHA, and NMAB. The one you choose could have a significant impact on your plant’s safety, and could be costly. 

1. The historical practice has been to use the recommendations from the National Materials Advisory Board (NMAB) report 353-3-80, “Classification of Combustible Dusts in Accordance with the National Electrical Code”, which defines dusts having Ignition Sensitivity (IS) ratios greater than or equal to 0.2 or Explosion Severity (ES) ratios greater than or equal to 0.5 to be appreciable explosion hazards requiring electrical equipment suitable for Class II locations.

2. These ratios are relative measures relying on extensive testing (such as the Pmax, KSt, MIE, MEC, and MIT). The ratios compare these explosibility characteristics of the dust under consideration against Pittsburgh Pulverized Coal.  OSHA has adopted the NMAB interpretation of a Class II dust in their combustible dust national emphases program.

3. Recent changes to the recommended practice NFPA 499 stipulate that only a Go/No-Go explosibility screening test per ASTM E1226 is needed to determine if a sample requires special attention for electrical classification followed by a Layer Ignition Test (LIT) and a Minimum Ignition Temperature Test (MIT) for dust clouds to establish appropriate electrical “T”-codes, thus replacing the former ES and IS ratio determination. This paradigm shift seeks to make a hazardous location determination more accessible (i.e., cost effective); however, it ignores key information that is essential for safe dust management.

4. The explosibility data which constitutes the ES and IS ratios can be used in the design of deflagration relief vents, deflagration suppression and isolation systems, housekeeping level requirements, set pneumatic transport limits, help establish electrostatic hazard avoidance like grounding and bonding protocols and provide guidance on safe operation temperatures. In fact, these data will be required for safe operation of a given process.

5. The Go/No-Go test alone does not provide the data required for effective explosion mitigation engineering. While these tests increase the costs of sample analysis, they provide the data that could have prevented an explosion.

When considering dust, different regulatory bodies have different approaches. If you have questions about what approach is appropriate for your material, please contact Dr. Ashok Dastidar, Fauske & Associates, LLC at 630-887-5249 or via email at

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