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.
The Ordinance on Occupational Safety and Health in Forestry proposes no more than 4 h of effective chainsaw work daily, while EU Directive 2002/44/EC proposes an EAV of 2.5 m/s2, and an ELV of 5 ...m/s2. The aim of this paper was to compare and assess the viability of the proposed restrictions. A case study in Croatia including 91 felled and processed trees, a detailed time study, and vibration magnitude measuring on European beech wet wood in compliance with ISO 5349-1:2001 and ISO 5349-2:2001 standards were performed. The results implied that tree species, processing method, and DBH have no influence on the time structure of working hours. Using bigger and more powerful chainsaws resulted in higher A(8) values; it was also noted that the right hand is more exposed. On average, none of the observed chainsaws exceeded 5 m/s2 of A(8). It can be concluded that state legislature, which allows a maximum of 4 h of chainsaw work a day, is appropriately protecting chainsaw workers from vibration exposure, but is also obsolete (1986) as it only uses the time limit. In contrast, European legislature requires a methodical approach to A(8) calculation and leaves room for individual evaluation of specific chainsaw work, which opens up possibilities of extending or shortening some chainsaw operations.
Compiling the research on forestry ergonomics, which is still a marginal field in terms of the sheer volume of published forestry-related articles, gives a good foundation and guidance for future ...research and publishing. This review aims to compile, classify, and analyze forestry ergonomics publications in JIF (Journal Impact Factor) journals regarding their spatial and temporal distribution, observed operations, machines and tools, and risk factors. A reference period from 2014 to 2023 was observed in this study. The Web of Science Core Collection database was used to filter publications in the field of forestry and ergonomics. A total number of 102 articles were selected. After selection, data regarding publishing year, journal name, main field, country of origin, forest operation, machine/tool, and risk factor were noted. The number of articles is ever-increasing with the last four years having above average numbers of articles. Countries from Europe and South America (Brazil) have the most publications. Most of the journals are ranked in the top 50%. Harvesting, wood extraction, and pre-harvesting operations have the highest number of records. Chainsaw, skidder, and pre-harvesting tools are the most observed means of work. The risk factors with the highest percentage of records are workload (23%), noise (20%), vibration (20%), postural load (16%), and MSD (Musculoskeletal Disorder) occurrence (7%).
The application of various graphic analytical software solutions in the research aimed at designing and determining the ergonomic and biomechanical harmony between forestry workers’ anthropometric ...measures and their working positions and movements is still scientifically incomplete and largely unexplored in forestry, especially regarding motor manual work with chainsaws. Accordingly, the aim of this research is to numerically represent the general kinematic model of forestry workers’ upper body while starting a chainsaw. The same is determined by using a state-of-the-art motion capture suit with inertial measurement units (IMUs). An additional research aim is to investigate numerical values of the forestry worker kinematic model against the three potentially applicable methods of starting a chainsaw and work experience with a chainsaw. Field data collection was carried out during the spring and summer of 2022 and 2023, and a total of 51 chainsaw workers were sampled in different relief areas. The results of the subject research show that none of the observed methods of starting a chainsaw are entirely safe for the worker, concerning the aspect of MSD development, if the body movements within the working element are performed in an incorrect way. From safety and kinematic aspects, regarding forestry workers’ upper body values, the most neutral work posture (N-pose) is when a worker is using the “between the knees” method. The method “from the ground” can be used as secondary option if the workers are educated in taking the correct position of the upper body, i.e., to practice the rule of hip hinge. With the aim of extending the working ability and working life of forestry workers, interdisciplinary cooperation between occupational medicine, kinesiologists, and forestry experts is needed to create a guide of statodynamic efforts and correct postural movement habits during motor manual work in logging operations.
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.
Professionally trained, motivated, and responsible forestry workers are a fundamental prerequisite of successful forest production and an integral part of the modern, generally accepted paradigm of ...sustainable forest management. However, the forestry sector today is increasingly facing the problem of a shortage of forestry workers and the challenge of obtaining a qualified and sustainable workforce. This paper, therefore, presents the reflections of forestry workers on the challenges and future perspectives on their profession and forest work. The findings of the examination of forestry workers in Bosnia and Herzegovina include some general characteristics of forest work and indicators of the state and position of forestry workers (socio-demographic characteristics, attitudes toward work, profession, etc.). Specially addressed are some problems and challenges faced by the forestry sector in obtaining and recruiting the necessary workforce—the severity of the forestry worker shortage, the main causes and reasons for the lack of workers, factors for stronger recruitment and retention of workers, work commitment, sustainability of the workforce, future perspectives on forestry work, etc. The differences between workers employed in public and private forestry companies were examined. The survey included 268 respondents and was carried out in the second half of 2021. The purpose of the work was in sensibilizing the profession and the public to the issues of the workforce in forestry, its position, and reflections, and in providing the basis that can be an important contribution toward improving the condition and sustainability of the forestry workforce.
The aim of this research is to measure the energy consumption and compare the cutting performance of three types of battery-powered chainsaws (Stihl MSA 200, Stihl MSA 220, and Stihl MSA 300). Tested ...chainsaws were powered by two different battery packs (Stihl AP 300 S and Stihl AP 500 S) with different energy capacity and output current when cutting two wooden beams, European beech (Fagus sylvatica L.) and black locust (Robinia pseudoacacia L.) with different densities and moisture content. Energy consumption was measured using a multimeter built-in battery charger housing, and consumed energy was noted in watt-hours. Each individual cut was recorded with an action camera at 60 frames per second, and the duration of the cuts recorded in centiseconds was observed on the obtained recordings. Results show significant differences in energy consumption and cutting duration between individual chainsaw/battery combinations. Energy consumption ranged from 2.45 to 4.50 Wh per cut for beech (Stihl MSA300E_AP500S and Stihl MSA220_AP300S, respectively) and from 3.10 to 5.00 Wh per cut for black locust (Stihl MSA300M_AP500S and Stihl MSA220_AP500S, respectively). Duration of the cut ranged from 3.48 to 9.24 s per cut for beech (Stihl MSA300M/H_AP500S and Stihl MSA220_AP300S, respectively) and from 3.74 to 9.35 s per cut for the black locust (Stihl MSA300M_AP500S and Stihl MSA220_AP300S, respectively). In general, it can be concluded that more powerful chainsaw/battery combinations (Stihl MSA300_AP500S) consumed less energy per cut and had better cutting performance (shorter cut). In that regard, more powerful chainsaws had greater cutting efficiency, i.e., more cuts on one charge (battery) but shorter cutting time on one charge. The effect of tree species (fresh-sawed beech/air-dried black locust) on energy consumption and cutting performance is absent on the most powerful chainsaw/battery combinations. Today, lithium-ion batteries still have 70 times less energy density than petrol. However, if there is a significant increase in the energy density of the batteries in the coming times, battery chainsaws will most certainly displace petrol chainsaws from use in the future.
For the needs of fuel consumption analysis, a database for a period of 2 years was created for three types of skidders operating in two different management methods—even-aged and selective forests. A ...total of 436 skidders were processed in the database, of which 255 skidders worked in even-aged forests and 181 skidders worked in selective forests. The average consumption of skidders in even-aged forests ranged from 1.38 to 1.65 L/m3 or from 7.81 to 9.34 L/PMH, while in selective forests, the average consumption ranged from 1.06 to 1.34 L/m3 or from 6.49 to 7.10 L/PMH. The obtained results indicate higher fuel consumption for all three types of skidders in regular forest management. There is no statistically significant difference in fuel consumption between the studied skidders. Comparing fuel consumption in L/PMH, we notice that there was an increase in fuel consumption in relation to the age of the skidder.
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.
The paper presents the process of electricity and thermal energy production in a cogeneration plant and the process of wood pellet production. The aim of this study was to analyze the energy ...gain—EROI for energy products that are created as a product contained in electrical and thermal energy and the energy contained in wood pellets. According to the obtained results, the production of only electrical energy from wood biomass in a cogeneration plant was not sustainable from an energy point of view, since the obtained electrical energy was only 1.46 times greater than the input wood energy (EROIel = 1.46), while the obtained energy of the produced wood pellets was 4.82 (EROIpel = 4.82). According to the results of equivalent carbon emission, positive net value was achieved only with cogeneration plant and pellet plant working in synergy. Wood is a renewable source of energy, and its economic use can create a significant energy gain. However, due to the trend of using renewable energy sources and the increasing need for electricity, such a process of obtaining electricity is financially profitable, although it is not justified from the energy profitability and environmental sustainability point of view.
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