Explosion Data Determination

Laboratory Testing TÜV SÜD Schweiz Process Safety

Laboratory Testing TÜV SÜD Schweiz Process Safety

Determination of the safety-critical properties of substances, products and mixtures (bulk solids, hybrid mixtures)


Operators or persons responsible for operations involving the handling and processing of substances, products and mixtures.

your benefits

  • All tests performed by a single organization
  • Flawless data from an accredited testing body to establish safe operating conditions

our services

  • Determination of the maximum explosion pressure and the maximum rate of pressure increase (K value)
  • Determination of the lower and upper explosion limits
  • Determination of the minimum ignition energy for a dust explosion
  • Determination of the limiting oxygen concentration
  • Determination of the electrical resistivity of powders
  • Determination of ignition temperature
  • Determination of thermal stability
  • Determination of smoldering temperature
  • Determination of the impact sensitivity
  • Determination of the friction sensitivity

Special tests: Determination of the physical properties of solvents, solvent mixtures, emulsions and suspensions


Most databases on the physical properties of solvents contain only little information, and as a rule this only covers selected products such as acetone, methanol, etc. Plant operators using mixtures of solvents, or less known solvents, simply do not have the information necessary to conduct the process in a safe way.

the benefit for you

All tests for safety-relevant physical properties are accredited to ISO/IEC 17025.

our services

  • Determination of flash-point, fire-point and auto-ignition temperature (and minimum ignition energy up to 1 mJ)
  • Determination of the lower and upper explosion limits, explosion points
  • Determination of the maximum explosion pressure and the maximum rate of pressure increase
    (K value)
  • Determination of the limiting oxygen concentration
  • Determination of conductivity
  • Determination of the vapor pressure curve

special tests: Tests For Highly Toxic or Highly Active Substances

Many standard methods for safety tests of chemicals involve open handling of substance. For highly toxic or highly active substances, new test methods and equipment are therefore necessary.

In Switzerland TÜV SÜD Process Safety has developed such test methods and has validated them against acknowledged standards.

Traditional Hartmanntube

Closed Hartmanntube

During the test using test methods the substances are completely enclosed. The transfer of the sample into the test equipment or sample tubes is done under laminar flow conditions in special laboratory work stations. After the test, the substance is either burned directly inside the equipment, washed out in place or the sample tube is sent for incineration without opening.

Traditional impact sensitivity set-up

Closed impact sensitivity set-up

The following tests are available:

  • Decomposition Test DSC (Standard conditions or under inert gas)
  • Screening for Self-Ignition (DSC under 5bar O2; equivalent to the test according Grewer)
  • Decomposition test with simultaneous recording of pressure in an autoclave
  • Analytical characterization of decomposition gas
  • Screening for dust explosivity (equivalent to test in Hartmanntube)
  • Test for flammability of raised dust with a 10mJ spark
  • Sensitivity on Impact (Falling Hammer 80cm, 5kg)
  • Powder resistivity / conductivity
  • Charge relaxation time

Innovative Tools for the Friction Test


Sparks are observed even in the absence of any test material in the friction test according to Annex V of the EU Directive 67/548. Yellow/brown traces are found on the friction plates and a "smoke" odour is perceived.

These artefacts may lead to false assessments of the friction test, i.e. solids will show flame reactions, which due to their stability do not have the potential to react under mechanical stress. Artefacts were found in particular when testing substances with a melting point below 130°C.



In collaboration with FRIATEC ceramic friction tools made of SiO2-free material have been developed. These tools are essentially spark-free, without jeopardizing the sensitivity of the test.
The figures below shown artefacts for samples 1 and 2, when using conventional porcelain tools (left). With the new ceramic tools these artefacts have disappeared. When testing friction sensitive materials, the flame reaction appears also with the new ceramics (sample 3).

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