The Mackey test has been considered from the point of
view of its suitability as a general method for assessing the
spontaneous heating and ignition hazards of materials which
are subject to atmospheric oxidation. An experimental study
has shown that there is an optimum packing density for self-heating
in specimens of oiled fibre in the Mackey tester.
The Mackey test can be used to show whether spontaneous
heating can occur in a given material, and it may give an
indication of the possibility of spontaneous ignition under
practical conditions. But, if the test is to be used for
classification of materials in order of their liability to
spontaneous ignition, it may be necessary to determine the
optimum test conditions for each material. Further experimental
work is required to show if this, extension of the test is
praoticable.
