Calorimetry and Dust Explosibility Testing
Reaction calorimetry with RC1 and ARC alongside 20 litre sphere, MIKE, and Hartmann tube testing that generates ATEX and NFPA 660 design data
Calorimetry and Dust
Explosibility Testing
Specialised laboratory testing for reactive chemistry and combustible dust generates the engineering data that underpins vent sizing per DIERS and NFPA 68, suppression design per NFPA 69, ignition source control per IEC 80079 36 and EN 1127 1, and ATEX Zone classification per IEC 60079 10 2. The reaction calorimetry stack of DSC for milligram scale screening, RC1 for millilitre isothermal kinetics, ARC for millilitre scale adiabatic worst case, VSP2 and Phi Tec for 10 millilitre adiabatic two phase work, and Mettler Toledo HEL produces complementary datasets that feed Stoessel criticality and DIERS vent sizing methodology. The dust testing stack of the Hartmann tube for legacy MIE screening, MIKE 3 for modern MIE per EN 13821, the Godbert Greenwald and BAM ovens for MIT per EN 50281 2 1, the 20 litre sphere for Kst and Pmax per EN 14034 and ASTM E1226, and the MEC apparatus per EN 14034 3 generates the parameters required for Zone 20, 21, and 22 classification, vent area calculation, suppression bottle sizing, and inerting LOC determination. Most industrial powder facilities operate without site specific dust data and rely on generic K values that under protect their actual material, and both OSHA NEP and FM Global increasingly demand site specific testing, which is exactly what our team provides.

How the study is executed
A structured, facilitated process that runs from scope definition through close out and produces defensible, actionable outputs.
Prepare dust sample per ASTM E1226 / ISO 6184, sieve to typical 200 mesh (<75 μm), measure particle size distribution (laser diffraction), moisture content, and bulk density, align with NFPA 660 sample protocol.
Conduct explosibility screen per ASTM E1226 modified Hartmann tube or 20 L sphere, classify as explosible (yes / no) per NFPA 660 / IEC 80079 20 2, if yes, proceed to quantitative testing.
Conduct Kst and Pmax testing in 20 L Siwek sphere per ASTM E1226, calculate Kst (bar·m/s) and Pmax (bar), classify per ATEX Dust Class, St 0 (Kst=0), St 1 (0 to 200), St 2 (200 to 300), St 3 (>300).
Conduct MIE (Minimum Ignition Energy) per ASTM E2019, MIT (Minimum Ignition Temperature) per ASTM E1491 (layer) / E2154 (cloud), and LOC (Limiting Oxygen Concentration) per ASTM E2079, align with NFPA 660 / IEC 80079.
For hybrid dust gas atmospheres, characterise interaction effects, MIE depression, MEC reduction, Kst modification, conduct conductivity testing (volume resistivity per ASTM D257) for static ignition risk assessment.
Compile testing report with full Kst / Pmax / MIE / MIT / LOC / MEC results, align with NFPA 660 DHA (Dust Hazard Analysis) input requirements, specify vent sizing per NFPA 68 with Kst input, align with NFPA 69 suppression design.

What the study covers in full
Outcomes of Calorimetry and Dust Explosibility Testing
- We generate site specific data that replaces generic K values which under protect your actual dust
- We identify dusts with an MIE below 10 millijoules that require electrostatic bonding control
- We define defensible vent area, suppression mass, and isolation design
- We anchor the inerting LOC for your nitrogen blanketing strategy
- We meet the NFPA 660 2024 unified DHA data requirement
- We provide DIERS compliant calorimetric data for two phase vent sizing
- We support ATEX Zone classification per IEC 60079 10 2 with EN 14034 evidence
- We provide data that withstands FM Global and OSHA Combustible Dust NEP audits
- We target your dust collection ventilation design to the actual MEC and Kst we measure
- We drive grounding and bonding programmes against measured volume resistivity
- We set inerting nitrogen flow against the measured LOC
- We support realistic vent panel and isolation valve specification
- We help you avoid the 30 to 50 percent vent and suppression over specification that conservative generic values cause
- We reduce your inerting nitrogen consumption through measured LOC operation
- We target electrostatic control investment to genuine MIE risks
- We support your FM Global premium tier dialogue with measured data
Codes & standards we work to
Triggers that signal the need
Where Calorimetry and Dust Explosibility Testing applies
Wellheads, separators, gas compression, FPSO topsides, produced water systems.
Distillation columns, reactors, heat exchangers, storage spheres, LPG handling.
Cryogenic exchangers, liquefaction trains, BOG compressors, storage and sendout.
Reactive systems, batch reactors, solvent handling, runaway reaction scenarios.
Boilers, HRSGs, steam headers, hydrogen systems, ammonia SCR units.
Sterile vessels, CIP/SIP, pressure fermenters, solvent recovery, spray dryers.
Tangible deliverables
- DSC, ARC, RC1, and VSP2 and Phi Tec calorimetric test pack
- 20 litre sphere Kst, Pmax, and St class data per EN 14034
- MEC test data per EN 14034 3 and ASTM E1515
- MIE test data per EN 13821 using MIKE 3
- MIT cloud and layer data per EN 50281 2 1
- LOC determination for inerting
- Electrostatic property data covering resistivity and chargeability
- DHA ready test data package
- DIERS vent sizing input pack
- ATEX Zone classification supporting data
Ready to start your project?
Speak with our team to scope an engagement tailored to your facility, regulatory context, and lifecycle stage.