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CTL08 - Group A/B Flammability Screening Lab

Determines whether a dust is capable of explosion when dispersed as a cloud and exposed to an ignition source.


  • Screens for ignition sensitivity to electrostatic spark discharge and / or ignition sensitivity to exposure to a 1000 °C heat source (see options) to represent those ignition sources most commonly encountered in industry
  • Hot coil is relevant for any product processing above 110 °C
  • Small and compact
  • Extremely easy to use
  • Air supply can either be from a standard service air pressure within a laboratory environment or an air cylinder

flammability screeningflammability screening

For the Group A/B Classification of a dust cloud of powder product, this method requires a constant arc to be produced through the test sample. An ignition is an observation of flame propagation away from the ignition source. If at any time during the procedure an ignition is observed then the test is complete and the dust is classed as Group A Flammable.

Note that a Group B classification does not imply that the dust cannot be involved in a fire or show exothermic behaviour (self-heating). Other tests must be performed to establish this.

Functional Specification & Deliverables

  • Mains supply: 110 - 240 V a.c / 3 A
  • Dust / air dispersion base complete with steel mushroom for dust cloud optimisation - typically 7 barg service air required
  • 1 litre acrylic Hartmann Tube (can be cleaned with warm soapy water and dried)
  • Tube rupture papers (for top tube closure)
  • Brass electrodes for creating arc
  • Constant arc power source (10 kV)
  • Remote handset (arc and air activation)
  • 1 x instruction manual

Optional Extras

  • 1 litre glass hot coil tube and power source for screening of products that are to be processed on full-scale plant above 110 °C (comes complete with power source, hot coil holder and wire).
  • Spare electrodes
  • Spare rupture discs

Note: if a result is positive then full testing can be carried out in the MIT Cloud Apparatus CTL05.