Carolina Lombardini

Relating safety, productivity and company type for motor-manual logging operations in the Italian Alps

The study compared the performance of four different logging crews with respect to productivity, organization and safety. To this purpose, the authors developed a data collection method capable of providing a quantitative analysis of risk-taking behavior. Four crews were tested under the same working conditions, representative of close-to-nature alpine forestry. Motor-manual working methods were applied, since these methods are still prevalent in the specific study area, despite the growing popularity of mechanical processors. Crews from public companies showed a significantly lower frequency of risk-taking behavior. The best safety performance was offered by the only (public) crew that had been administered formal safety training. The study seems to deny the common prejudice that safety practice is inversely proportional to productivity. Instead, productivity is increased by introducing more efficient working methods and equipment. The quantitative analysis of risk-taking behavior developed in this study can be applied to a number of industrial fields besides forestry. Characterizing risk-taking behavior for a given case may eventually lead to the development of custom-made training programmes, which may address problem areas while avoiding that the message is weakened by the inclusion of redundant information. In the specific case of logging crews in the central Alps, the study suggests that current training courses may be weak on ergonomics, and advocates a staged training programme, focusing first on accident reduction and then expanding to the prevention of chronic illness.

Productivity and Cost of Industrial Firewood Processing Operations

Abstract The study determined the performance of industrial firewood processing operations under the typical work conditions of Southern Europe. In particular, we surveyed five commercial operations processing 1-m-long oak logs from coppice forests. Mean log volume was very small, in the range of 0.01 to 0.02 m3 solid. Machine utilization was quite high, ranging from 70 to 80 percent. Mechanical availability was excellent, always exceeding 90 percent of the total worksite time. Productivity varied between 1.4 and 4.9 m3 per scheduled machine hour (SMH), inclusive of all delays. Processing cost ranged from 26 to 44 €/m3. The largest machine in the group offered significant productivity and cost benefits over all the others. Owing to their multiple log handling capacity, firewood processors designed for Southern Europe may be less sensitive to log volume, compared with Nordic machines. The energy balance was always very favorable. The ratio between output and input was never smaller than 220 and peaked at 3...

The effect of carriage type on yarding productivity and cost

ABSTRACT The authors describe a study conducted under controlled conditions, with the goal of determining the eventual benefits of replacing the conventional clamped carriage with an unclamped motorized dropline carriage. The rigging was a classic three-cable configuration common to European yarder operations, with a single span standing skyline. The mainline and haulback line were used to move the carriage back and forth along the span. Two carriage types were used to gauge productivity and extraction cost differences between clamped (Hochleitner BW4000) and unclamped motorized dropline (SEIK Skybull 30/60) carriages. The authors conducted a classic time study, recoding work time, delay time and load size individually for 83 cycles. Replacing the standard clamped carriage with the unclamped motorized dropline carriage resulted in a productivity increase equal or larger than 30%. Extraction and processing cost decreased between 10% and 17%, depending on extraction distance. These results are valid for the specific set-up considered with the study, and may not be generalized without repeating the experiment under more varied conditions: however, they are very encouraging and may justify further investigations aimed at determining the effect of carriage type on fuel consumption and machine wear.