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Timber harvesting, especially motor-manual felling, in Croatia, as in many other countries, is one of the most hazardous economic activities. Consequently, the aim of this paper is to analyse and compare the latest trends and risk factors related to the incidence of work-induced injuries in structural organization units of national forest enterprise. A combined approach of literature review and assembled secondary data was applied to gather data on workplace accidents over the years 2014–2020. Work-induced injuries data were drawn from the records of the national enterprise Croatian Forests Ltd. which manages state forests (76% of total forest area). A total of 1626 work-induced injuries were processed and entered into the database. Data analysis was conducted using statistical and descriptive methods. Research results have proven a significant difference in the injury rate over the years 2014–2020 in the Croatian forest enterprise. During the analysed period the highest number of workplace accidents (51.35% of all recorded workplace accidents) occurred during the forest harvesting phase, i.e., during motor-manual felling. Trends in the incidence of work-induced injuries in the observed period do not show any significant improvement. The key findings have pointed out that forest administrations which practice even-aged forest management have 25% or more injuries than forest administrations which practice selective forest management. Related to the average rate of change by forest administration, the largest annual increase or decrease of the selected safety indicators is recorded for smallest forest administrations. Related to total number of injuries, the smallest forest administrations have the least injuries and show statistically significant difference compared to large forest administrations. When comparing the number of injuries per 1000 employees, medium sized forest administrations have the highest value of indicator and show statistical significance. Discussion and conclusion of the paper emphasizes the need for systematic research in the field of ergonomy, safety and health of forest workers in Croatian forestry sector. Additionally, the development and inclusion of proactive safety culture is recognized as a mechanism that can further reduce work injuries and improve occupational safety which should have a significant role in the process of certification of forest management according to the FSC standard.

Although professional chainsaws have come a long way regarding technical and ergonomic development since first introduced into forestry, they still remain a high-risk tool that can cause serious health problems. In this research, three types of used professional chainsaws were observed regarding harmful vibrations they emit and possible connection to years in use, chainsaw type, characteristics and level of vibrations. Measurements were performed in accordance with the recommendations of ISO 5349:2001. For the measurements, a measuring chain consisting of a triaxial accelerometer manufactured by Bruel & Kjaer and a vibrometer of the same manufacturer Type 4447. To evaluate the emitted vibrations, a daily exposure value A(8) was used. Exposure durations to predefined working operations were identical for every used chainsaw to enable the possibility of equal comparability. Obtained results indicate that the daily vibration exposure A(8) is not affected by the years in use of the chainsaw. Results also show that the power and chainsaw type have an influence on daily vibration exposure. The recommendation for the praxis is to use even lighter and smaller chainsaw wherever is possible.

Background and Purpose: Due to technological progress and improvement of working processes, significant changes in the field of health protection and safety at work have occurred in the forestry sector. Accordingly, this paper presents the assessment and comparison of the working posture for operators of three different types of forest machines: chainsaw, forwarder and harvester. Materials and Methods: The analysis was carried out from an ergonomic point of view using ErgoFellow 3.0 software, i.e. two ergonomic methods: Ovako Working Posture Analyzing System (OWAS) and Rapid Entire Body Assessment (REBA). Field measurements and data collection were carried out during the summer of 2017, when different wood harvesting technologies were applied within the same forest stand. The operators’ body posture was recorded during effective work by a video camera and was taken as a relevant comparison factor of different types of forest machines and three observed operators. From the video recordings, the working body postures were defined in accordance with the snapshot method with the aim of obtaining an equal number of observations for all three operators of forest machines. Results and Conclusions: The results of the analysis of the working posture for operators of all three types of forest machines show that, in terms of the level and type of their impact on the worker, the work of the chainsaw operator is more demanding and much more risky than that of the harvester or forwarder operators. The comparison of the two risk categorization methods, from the aspect of the working posture, shows that the REBA method has higher risk ratings than the OWAS method for all three types of forest machines. The need to implement preventive measures established in Scandinavian countries and to define the guidelines for future research of the working postures of forest machine operators is presented in the discussion of this paper.

Forest cleaning, being an operation that requires investment, but the return on investment is due for the next generations, utilizes tools and methods that mostly haven’t been humanized. Harmful vibration is still present in today’s forestry operations, and new tools provide possible reduction of exposure to vibrations. Petrol chainsaw and battery chainsaw (late cleaning) and billhook, machete, and battery shears (early cleaning) were used and observed in this study. Vibration levels were measured and assessed using validated Brüel & Kjær 4447 vibrometer which complies with the ISO 8041:2017 standard. The measurement was performed according to the recommendations of ISO 5349-1:2001 and ISO 5349-2:2001 standards. Vibration exposure was assesed using work sampling method on the obtained video recordings in order to calculate relative shares of different work elements. Results show that hand tools (machete and billhook) are causing the highest vibration levels, while battery shears cause the lowest. Battery chainsaw causes higher vibration levels while cutting, but lower daily vibration exposure than petrol chainsaw. A detailed revision in the classification of tools is needed, considering their ability to produce and transmit harmful vibrations to the operator. Using the current classification, the daily exposure to vibration of workers in early forest cleaning is high above legislative values.

Motor-manual felling and wood processing is a high-risk work process where the chainsaw, in connection to other variables in the working environment, is a key and constant source of risk and danger for forest chainsaw operators. Pursuant to the foregoing, the purpose of this research is to investigate and compare detected musculoskeletal disorder (MSD) symptoms among the chainsaw workers in Croatia according to their employer (state company – Hrvatske šume Ltd. or private forestry contractor) and self-evaluated Workability Index. A combined three-stage research method was used: (a) defining a sample; (b) preparation and administration of questionnaire; and (c) data analysis and elaboration. The Standardized Nordic Questionnaire (SNQ) was used as a medium to detect musculoskeletal disorder symptoms in chainsaw operators and the Workability Index (WAI) questionnaire was used as a medium for workability self-evaluation. The field part of face-to-face data collection was conducted in the first quarter of 2022 with a total of 158 sampled workers interviewed directly at the forest worksite. Descriptive and inferential statistical methods were used to verify and analyze the data. The anatomical area with the highest 12-month period prevalence of MSD symptoms for all chainsaw operators is the low back (70.89%), followed by the shoulders (41.14%), neck (39.87%) and wrist/hands (36.71%). Research results, according to the employer, showed that workers employed by Hrvatske šume Ltd. have a higher prevalence of MSD symptoms in almost all anatomical locations compared to chainsaw operators employed by private forest contractors. Mean WAI Score among all respondents was 34.96 points (max. 49) falling into the rank »moderate«, while the current workability compared with the lifetime best was 7.33 (range 0–10). The results of MSD symptoms confirm the self-estimated higher values related to health problems caused by forestry work and lower WAI Score by workers employed in the state forestry sector compared to workers employed in private forestry sector. The prevalence of MSD symptoms, observed through WAI Score, showed a significantly lower percentage of affirmative responses for all anatomical regions except for shoulders in workers who need to maintain their workability. The obtained results show positive correlation with descriptive indicators, where younger workers with less chainsaw work experience have a lower prevalence of MSD symptoms and better WAI Score. In the discussion and conclusion part of the research in question, the need for development of possible solutions is emphasized. The proposed solutions can be included into educational programs or on-site training related to the MSD risks for professional chainsaw workers to change their behaviour that will reduce occupational risks.

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Motor-manual work with a chainsaw is still an irreplaceable occupational activity in forest harvesting operations in Croatia and in many other countries. Chainsaw workers are exposed to different risk factors, such as noise and vibrations, heavy load lifting, awkward and preflexion postures, repetitive movements, etc. The working posture and the assessment of the center of mass plays an important role in understanding the exposure of forest workers to postural and occupational risks, either as a part of the entire work process or as a part of an individual element of the work technique. Therefore, the aim of this research was to investigate the impact of three different chainsaw starting methods (from the ground, between the knees, and “drop starting”) on the postural load of the chainsaw worker and its association with personal and occupational factors. The field portion of data collection was conducted in the second and third quarters of 2022. For trunk posture assessment (n = 74), the rapid entire body assessment (REBA) tool was used, and for the center of mass measurement (n = 28), the Xsens MVN Link motion capture suit was used, a relatively new technology that allows data collection in real field conditions. Descriptive and inferential statistical methods were used to verify and analyze the field data. Based on the obtained results, almost 50% of the sampled chainsaw workers ignored safety instructions and preferred “drop starting” a chainsaw. The results also showed that there is a significant difference between the three starting methods in the REBA score, as well as in the number of segments scored during the assessment. The obtained mean REBA score for all three methods is between 4 and 7, placing all methods at a medium level of MSD risk. Regarding the analysis of the Center of Mass (CoM) vertical deviation, the statistical difference is noticeable for the body mass index (BMI) group, the group related to experience with the chainsaw, and the age and height group in relation to three methods for starting a chainsaw. The safest method, which implies starting a chainsaw from the ground, resulted also as the riskiest in terms of postural strain, which, cumulatively over the time variable, can contribute to health problems in forest workers. In conclusion, related to the future process of professional training development for chainsaw workers, an integral part of the training must contain the most optimal postural-movement habits that need to be defined by further kinematic research in forestry.