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CTL06 - Litre Sphere Test Apparatus

Determines the explosion severity (maximum pressure and speed of explosion) of a dust cloud under specified test conditions.


  • Data applicable for explosion vent sizing, suppression & containment design
  • Compact size compared to testing with 1m3 sphere and uses less sample
  • Allows accurate vent sizing calculations for full scale plant
  • Easy to use
  • Automated ignition and data acquisition system
  • Optional accessories eg. seals, lifting gear to assist with head removal / refitting, Limiting Oxygen Concentration control unit together with modification service to take nitrogen feed-line and optional full commissioning and training package also available

litre sphere test

20 litre sphere test apparatus with optional lifting gear shown

The 20 Litre sphere test apparatus is used to determine the explosion severity (maximum pressure and speed of the explosion) of a dust cloud under specified test conditions. The dust is dispersed in the 20 litre explosion chamber by injecting it from a dust container pressurised with air at 20 bar. By pre-evacuating the explosion chamber, the ignition is initiated by very powerful chemical ignitors (2 x 5 kJ chemical ignitors), at atmospheric pressure. The delay time is the period between start of dispersion and ignition and is chosen to obtain results commensurate with the standard 1 m3 vessel.

The pressure-time history is measured and, for each test, the maximum explosion pressure (Pm) and maximum rate of pressure rise ((dP / dt)m) are established and recorded to a PC. The resulting data is normalised to a 1 m3 vessel. The test is conducted according to BS EN 14034 parts 2 & 3 and ASTM E1226.

Functional Specification and Deliverables

  • Mains supply: 110 - 240 V a.c operation
  • 20 litre sphere for dust explosion testing
  • Data control unit – interfaces with measurement piezoelectric sensors via charge amplifiers and sends pressure and control data to / from PC
  • Ignitor initiation unit – sends ignite signal to chemical ignitors and also filters the air and contains air inlet lines
  • Set of spare parts
  • 1 x instruction manual

Please note: customers outside the UK may, due to transport logistics reasons, have to source their own ignitors. Details available on request.

Optional Extras

  • Lifting gear
  • Vacuum pump
  • Ignitor storage safe
  • Full commissioning and training package in safety operational aspects and use of the 20 litre apparatus
  • LOC control unit and 20 litre mods to accommodate this unit
  • Capacitance spark unit (for researching low energy electrostatic effects on ignition)

The following is available at an additional cost:

  • PC with 20 litre software pre-loaded