Principle of Comparative Time Studies in Mechanized Forest Work

The principle of comparative work studies was tested in grapple loading by a forest machine simulator. The comparison was between loading in clear-cutting and thinning conditions. The principle seemed to work in the form presented by Harstela (1975), i.e. that the variation of the relative time expenditure between work methods was smaller than the variation within one method when the same subjects worked by both methods.