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.

Recent Posts

Combustible Dust Basics, Part 1: What does a Go/No-Go Test Mean?

Posted by The Fauske Team on 03.18.14

Go no go ChartVery often, when performing dust and explosibility testing quotes for customers, we are asked what exactly a Go/No-Go test is?  While we offer a list of testing services to determine the deflagration hazards of dust samples per ASTM International, OSHA (Occupational Health & Safety Administration, NFPA (National Fire Protection Agency) and UN (United Nations), knowing what this basic test is can go a long way for tackling your safety needs.

In order to "screen" for the possibility of dust cloud explosibility in your facility, we perform a Go/No-Go Explosibility Screening Test.  Based on ASTM E1226, "Standard Test Method for Explosibility of Dust Clouds", this test is an abbreviation of the explosion severity test method looking at a limited number of dust concentrations to determine if the sample is explosible.  This test is generally performed with samples tested "as received" or sieved with a 40 mesh (420μm) screen and using one 5-kJ chemical igniter as the ignition source.  [>100 grams (~¼ lb) of sample less than 420μm required]

In a previous post: "How To Collect and Ship Combustible Dust Samples For Testing", we discussed the simple steps for getting your samples to a lab for testing. The chart provided in this article discusses the outcomes for your dust tested.  If your test sample is a "Yes, it explodes" then further tests can be run to determine how quickly and how severe the explosion will be (KSt/Pmax Test), followed by testing what concentration of dust in the air will cause a risk of explosion (MEC Test).  Next, another test can determine if a spark will cause an explosion (MIE) test.

But, what if your Go/No-Go test result is a "no"?  Well, we next look at what temperature it will take make your dust ignite. To find the Minimum Autoignition Temperature (MIT) of a dust cloud in the air, the MIT tests the minimum temperature that would cause your dust cloud to ignite. Next, is the Layer Ignition Test (LIT), which determines the hot-surface ignition temperature of a dust layer. Finally, a VDI 2263 burning behavior test is conducted to determine if a dust will burn and if it does, how quickly it will spread. It is followed up by a UN 4.1 Burn Rate test for additional confirmation.  

All of these tests start with the Go/No-Go Test.  A comprehensive Process Hazards Analysis (PHA) can apply your test results to real world scenarios at your facility. Better to know what you are dealing with so you can plan safely!

Here are some other tests run for dust explosibility screening:  

  • Combustible Dust Screening Test - Based on VDI 2263 burning behavior test (for organics) and UN 4.1 combustion screening testing (for metals). These tests determine if a dust in a pile supports self-sustaining flame propagation. [>30 grams(~1oz)of sample less than 420μm required; >300 grams (~2/3 lb) of sample less than 420μm required if testing metal dusts]
  • Go/No-Go Screening + Combustible Dust Screening Package - Both tests run in tandem as a screening package
  • Sample Characterization Test - includes determining the sample moisture content and particle size distribution [>30 grams of samples less than 420μm required]
  • “Hard-to-ignite” Explosibility Test - Tested as above but with a 400 J ignition source. [>100 grams (~¼ lb) of sample less than 420μm required]

Unless otherwise instructed, dust testing is performed on the sample as it is received (“as received”) from your facility as mentioned earlier. It may be screened to less than 420 μm (40 mesh) – OSHA’s and NFPA’s demarcation of a “dust” – to facilitate dispersion into a dust cloud. Particle size may vary widely depending on the sample. 

Furthermore, please note that per ASTM recommendations (and some NPFA requirements); samples should be tested at a particle size less than 75 μm and less than 5% moisture. Please note that testing materials in a method not complying with the ASTM/EU recommendations may produce explosion severity and explosion sensitivity data that is not considered conservative enough for explosion mitigation design.

In our next article: "Combustible Dust Basics, Part II: What Testing Do I Need?" we will discuss more detail on the why and the how of available tests.  

For more information on your dust testing questions or needs, contact Jeff Griffin at griffin@fauske.com or 630-887-5278.

 Is My Dust Combustible?

Topics: Combustible dust, explosive dust, dust hazard, explosion severity test, explosibility test, MIT test, Minimum ignition temperature test, mitigating dust, NFPA 654, combustible hazard, NFPA 652, NFPA 68, NFPA 69, go/nogo, dust test, process hazards analysis, process hazards, MIE test, burn rate test, testing

cta-bg.jpg

Is My Dust Combustible?

A Flowchart To Help You Decide
Download Now