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Combustible Dust

EMSL Analytical, Inc. is headquartered in Cinnaminson, New Jersey, where all of our combustible dust testing is completed in our new state-of-art-the-art testing facility. 

We offer an extensive array of combustible dust testing.  Here at EMSL Analytical, Inc., we work to create interpersonal relationships with our customers to provide the best services possible.  We will work with you thoroughly in order to determine which tests best fit your needs.  Our experts and staff will work to ensure you receive the best service possible.  Service includes compliance with standards such as Occupational Safety and Health Administration (OSHA) and American Society for Testing and Materials (ASTM), data explanation, delivery of results in a timely manner, and reliable results.


Why Test for Combustible Dust?

In 2008, a sugar refinery owned by Imperial Sugar in Port Wentworth, Georgia exploded.  The explosion caused 14 fatalities and injured 40 individuals.  The incident was caused by a combustible dust explosion inside the facility.  Since the explosion, OSHA has issued directive “OSHA Combustible Dust National Emphasis Program CPL 03-00-008”.  This instruction “contains policies and procedures for inspecting workplaces that create or handle combustible dusts”.  Please click link for more information on OSHA CPL 03-00-008 (insert OSHA Instruction Here).


Material Science Division Combustible Dust Testing Services

Combustible dusts include the following materials and are not limited to:

  • Metal dusts (Magnesium, Bronze, Aluminum)

  • Wood (sawdust and flour)

  • Coal Dust

  • Organic Dusts (flour, paper, milk powder, whey protein, plastic, sugar, corn, etc.)

  • Epoxy Powder and Resin dust

  • Lists of Tests, Methods, and Definitions related to Combustible Dust Testing

  • Initial Analysis/Sample Characterization


Method OSHA ID201SG

This is the beginning of any combustible dust analysis.  The initial analysis/sample characterization includes percent combustible material, percent combustible dust, and particle size data. 


Abbreviated Sample Characterization

This analysis is used to determine the composition of the material if a Material Safety Data Sheet is unavailable.  The results are not reported.


Go/No Go Screening Analysis 

Method ASTM E1226-12 “Standard Test Method for Explosibility of Dust Clouds”

This is an explosive screening test.  It is an economical and practical way to determine if the dust in the sample has the propensity to be explosive.  The dust is submitted to low powered chemical igniters inside of the 20-L Siwek explosion chamber to determine explosion overpressure.  If the dust is found non-explosive, the analysis can be aborted.  If the dust is found to be explosive under the screening test, the more comprehensive analysis listed below should be conducted. 


Explosion Severity (Kst, Pmax, dP/dtmax)

Method ASTM E1226-12  “Standard Test Method for Explosibility of Dust Clouds”

This test is used to determine deflagration parameters of dust.  The dust is dispersed inside of the 20-L Siwek chamber and submitted to a 10kJ chemical igniter.  The dust is tested over a range of concentrations to determine the maximum pressure inside the chamber (Pmax), the rate at which this explosion occurs (dP/dtmax), and the Kst (explosion severity) value.


Combustibility Screening Test

Method VDI 2263 “Dust fires and Dust Explosions”

A dust is considered explosible if there is flame propagation after igniting the dust/air mixture resulting in a pressure rise.  This test is conducted in the Hartmann 1.2 Liter Vessel.  The sample is tested over a range of concentrations and is submitted to a continuous induction spark as an ignition source. 


Minimum Explosive Concentration (MEC) 

Method ASTM E1515 – “Standard Test Method for Minimum Explosible Concentration of Combustible Dusts”

This test is used to determine the minimum amount of dust that will sustain combustion.  The dust is dispersed in the Siwek 20-L explosion chamber and submitted to a 5kJ chemical igniter.  The dust is tested over a range of concentrations to determine the minimum explosive concentration.


Minimum Ignition Energy (MIE) 

Method ASTM E2019 – “Minimum Ignition Energy of a Dust Cloud in Air”

This test is used to determine the minimum ignition energy of a dust cloud in air by a high voltage spark.  


Minimum Ignition Temperature (MIT) 

Method ASTM E1491-12 “Minimum Autoignition Temperature of Dust Clouds”

This test is used to determine the minimum temperature at which a dust cloud will auto ignite when exposed to air in a furnace at atmospheric pressure.  This testing is applied to dusts that may come into contact with heated equipment such as dryers and ovens.


Volume Resistivity and Charge Relaxation Time 

Method ASTM D257-99 “Standard Test Methods for DC Resistance or Conductance of Insulating Materials”

This test is used to determine the nature of a dust with regards to electrostatic hazards.  The electrical nature of a dust is one criteria to determine if it is necessary to take special precaution with regard to electrical insulation of the equipment operating in a location with Class II dust.


Limiting Oxygen Concentration (LOC) 

This test method is designed to determine the limiting oxygen concentration of a combustible dust dispersed in a mixture of air with an inert/nonflammable gas. 


Layer Ignition Temperature (LIT) 

Method ASTM E2021 “Standard Test Method for Hot-Surface Ignition Temperature of Dust Layers"

This test method is used to determine the hot-surface ignition temperature of dust layers by measuring the minimum temperature at which a dust layer will self-heat. 


Ignitability of Solids 

Method EPA1030/ CFR § 49.173

This method is suitable for the determination of the ignitability of solids.  Material is formed into an unbroken strip or powder train.  An ignition source is applied to one end of the test material to determine whether combustion will propagate within a specified time period.  If propagation occurs, material is submitted to a burning rate test.  In the burning rate test, burning time is measured over a distance and a burning rate is determined.  Materials that do not ignite or propagate combustion do not require further testing. 


Class II Dust Analysis – includes Initial Analysis/Sample Characterization, explosion severity, MEC, MIE, MIT.

This level of testing involves a number of parameters that determine if the sampled dust is considered a Class II hazardous material. Class II locations are defined as locations with combustible dust having Ignition Sensitivity (I.S.) greater than or equal to 0.2 or Explosion Severity (E.S.) greater than or equal to 0.5. I.S. The I.S. value is calculated from MIT, MIE, and MEC for the sample and compared against the normalized I.S. value of Pittsburg coal dust. The E.S. value is calculated from Pmax and [dP/dt]max for the sample, and compared against the normalized E.S. value of Pittsburg coal dust.



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