A study was conducted to determine the effect of some wood characteristics such as species, moisture content and tree part on the performance and product quality offered by a mobile industrial chipper, of the type commonly used for roadside chipping. Two main species, two tree parts and two moisture content levels were combined in a factorial design yielding 8 treatments, each replicated 5 or 6 times. A flow meter was installed on the chipper engine, and all chips produced were weighed and sampled for moisture content and particle size distribution. The results indicated that some wood characteristics such as species and moisture content have a secondary effect on chipper productivity and fuel consumption, which are primarily controlled by piece size. In particular, fuel consumption per unit dry mass seem to be rather constant and in the range of 3.2 l per oven dry ton. Moisture content and tree part may have a significant effect on the particle size distribution of chips. Of course, these results were only verified for the species used in the test and for industrial chippers, and may change if substantially different species or machines are used.

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Objective: To identify the critical behaviors that may hinder the correct use of foldable rollover protective structures (FROPS) on tractors and to explore the influence of user factors and FROPS technical characteristics. Background: FROPS are effective in preventing fatal injuries in rollover accidents if they are in the upright position. However, many farmers leave FROPS folded down. Method: Twenty farmers and sixteen models of tractors were involved in the study. Operators were observed while raising the FROPS, and the observed behaviors were correlated with user factors and FROPS technical features. Results: In the initial rotation of the FROPS, higher lowered roll-bar to ground distance and FROPS pivot-pin to ground distance required more awkward and unbalanced postures ( p = .02 and p = .01, respectively). When rotating the FROPS in upright position, smaller stature of the participants and higher FROPS pivot-pin to ground distance were significantly correlated with using the tractor’s rear 3-point lower links as a supporting surface ( p = .01 and p = .02, respectively). Conclusion: FROPS might be revised considering users’ comfort in use and anthropometric variability, to improve reachability, avoid risky behaviors, and enhance FROPS operation. Application: Technical solutions to enhance FROPS accessibility may be developed, particularly by providing safe surfaces to support operators and highlighting the grasping points. Further best practices and information on correct gestures to handle the FROPS should be included in the tractor manual.