Standards for Time Studies for the South African Forest Industry

Ackerman PA, Gleasure E, Ackerman SA, Shuttleworth B
Publication Type
Publication Year
ICFR/FESA Handbook

This South African Standard for Time-studies will provide a common and standard time-study methodology for the South African Forest Industry; a protocol that does not currently exist. Its implementation will serve the purpose of aligning the South African Forest Industry with international forest operations development and assist with the "modernisation" of the Industry’s forest operations. The concept of modernisation essentially includes updating forest operations in terms of both mechanisation and other modern systems improvements with the goal of improving wood/fibre yield, wood/fibre quality and reducing production costs to remain locally and internationally competitive.

The Standard has been compiled by those with specific expertise in work- and time-studies, particularly the statistical analysis component and machine costing. The Standard, with the inclusion of an internationally standardised Machine Costing Model, was developed based on accepted and validated international Time-study standards, protocols and literature. This Protocol is envisaged to be a state of the art model to benefit the South African Forest wood supply chain.

The Standard will be web-based and will guide the user step-by-step through the set up and execution of time studies and their application in Operations Research analysis. The standard deals with the setting of time-study objectives to ensure that time and resources are used efficiently and help to develop the desired results. Three types of studies, observational, experimental and modelling, are introduced. Different techniques are provided to control bias (i.e., systematic error) including randomisation and blocking.

The Standard contains sections on experimental study design, data collecting methodologies including sample size calculations; time study models; selecting an appropriate time study technique; statistical analysis and methods to best analyse the data collected; and ways to use and proceed with the results achieved through linkage with a machine costing model. The user will also be able to calculate machine availability, utilisation and systems efficiency ratios that are useful in determining systems efficiency. Background data forms, a terrain classification, templates to create data collection forms for the user’s study and a brief discussion on available time study software and equipment are also included.

Included in the Standard is a Time-concepts model developed by the International Union of Forest Research Organisations (IUFRO), useful for the precise division of common time elements included in all work and production systems.

The Standard also describes in detail the six different scopes of time studies, ranging from wide to narrow. These studies are shift-level, plot level, cycle level, time and production count, working sampling and the element level. Each study has different strengths and weaknesses and requires a specific technique which is discussed. A statistical analysis manual is also in the drafting stages and will aid the user through conducting their analysis and interpreting the results.