The present report describes design and testing of a method for the practical assessment of the loads in the hand-arm area due to small action forces and greater frequencies or duration.

The result is the draft of a "Key Indicator Method Manual Handling Operations". It supplements the existing methods for assessing working conditions for lifting, holding, carrying and for pulling, pushing. In accordance with the principle of the Key Indicator Methods it includes an objective description of requirements and loads and specifies the possible hazards of physical overload. It takes account of reliably evident activity indicators and their interaction. Key indicators to be taken into account are:

• daily duration of the activity
• nature, level and frequency of the application of force
• physical posture
• hand-arm position
• work organisation
• working conditions.

The key indicators are quantified in individual scales. The scales correspond to the conditions encountered in practice and range form minimum/optimum to maximum/poor. The classification on these scales gives an indication of any load bottlenecks. A total can be obtained by multiplying the scale value for the daily duration by the sum of the other scale values.

A risk assessment is possible which takes account of additional work-organisational and individual indicators.

The elaboration was conducted on the basis of a comprehensive and critical literature analysis, follow-up evaluations of own studies, a review of the actual forms of work and load structures in Germany and the experience accumulated with the application of the Key Indicator Methods. A total of 53 people were involved; scientists, supervisory personnel from State offices and Berufsgenossenschaften (institutions for statutory accident insurance and prevention), company doctors, safety specialists and management personnel from 28 companies in various sectors. Once an initial draft had been created, it was discussed with the potential users on the spot at 112 workplaces and developed further iteratively.

Then two unaccompanied test projects were conducted in the agricultural domain by supervisory personnel from a State Office for Occupational Safety and Health. The results of the method trial are acceptable. The breakdown of the assessment results corresponds to the range in operational practice. Approximately 20 % of the activities are in the "green" zone and 10 % in the "red" zone. With 70 % of all activities an increased load was found. The evaluations were nearly all credible and agreed with the operational experience.

The draft was published for the purpose of field trials. In a follow-up project it is being evaluated scientifically.

Please download the complete report "Key indicator method manual handling operations" (in German only).