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.

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

Recent Posts

Maximum Experimental Safe Gap Test Process

Posted by Fauske & Associates on 08.07.19

Michael Lim, Flammability and Dust Operations, Fauske & Associates, LLC

Industrial Background with Blue BarrelsProcess industries that handle flammable gases and vapors may involve concentrations that can potentially form an explosive atmosphere. In a situation where the right precautions are not taken into consideration, a flammable mixture may be exposed to an ignition source such as a static electric discharge, an electrical arc or a spark, which may ignite and potentially cause an explosion which can then result in personnel injury or damage to property.

Various regulations and standards have been developed to ensure a high level of safety in these hazardous conditions. The testing standards that have been established are aimed to provide information that can be used in engineering designs. An important piece of data that is valuable in designing explosion protection is the safe gap value or the maximum experimental safe gap.

The Maximum Experimental Safe Gap (MESG) is defined as the maximum gap between two flat surfaces, under specified test conditions, that prevents an ignition of a flammable gas/air mixture propagating from an inner chamber through a 25-mm long path into a secondary (outer) chamber. The data generated from MESG testing is commonly used as a guideline in installing properly sized flame arresters on process equipment. Additional information regarding flame arresters is found in NFPA 69 and ISO 16852.

The gases and vapors are classified into different explosion groups. Per NFPA 70, National Electrical Code, Class I locations are those in which flammable gases, flammable liquid-produced vapors or combustible liquid-produced vapors are, or may be, present in the air in quantities sufficient to produce explosive or ignitable mixtures. Class I locations are divided into divisions and zones depending on current or expected conditions. Material Groups, based on the MESG, are also used to further classify the explosive characteristics of specific gas/vapor air mixtures.

The Material Groups are as follows:

MESG Material Group Chart

a. The standard did not provide an MESG value

Per the European standard IEC 60079-20-1, the equipment is classified into groups in accordance with the properties of explosive atmospheres for which it is intended. The groups for equipment for explosive gas atmospheres are as follows:

Group I: Equipment for mines susceptible to firedamp

Group II: Equipment for locations with explosive gas atmospheres other than what was stated for Group I

Group II equipment is then subdivided into three sub-groups. For the purpose of classification of gases and vapors, the MESG limits are:

MESG Group II Chart

FAI has added testing capability to determine the MESG values of flammable gases or vapors. The test is performed in accordance with IEC 60079-20-1 and the setup is shown in Figure 1.

MESG Testing Setup

Figure 1: Setup for MESG Testing

The test equipment was verified by performing tests using propane and methane. The MESG values of the reference samples were determined in accordance to the IEC 60079-20-1 standard. Results obtained for MESG are compared with other reported literature values.

MESG Results of Propane and Methane

MESG Results of Propane and Methane
a. Data was obtained from IEC 60079-20-1 (2010)

For more information about MESG or other flammability testing, please contact us.


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Topics: Flammability


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