Ergonomic Evaluation of Current Advancements in Blueberry Harvesting

Abstract

Work-related musculoskeletal disorders (MSDs) accounted for 32% of days-away-from-work cases in private industry in 2016. Several factors have been associated with MSDs, such as repetitive motion, excessive force, awkward and/or sustained postures, and prolonged sitting and standing, all of which are required in farm workers’ labor. While numerous epidemiological studies on the prevention of MSDs in agriculture have been conducted, an ergonomics evaluation of blueberry harvesting has not yet been systematically performed. The purpose of this study was to investigate the risk factors of MSDs for several types of blueberry harvesting (hand harvesting, semi-mechanical harvesting with hand-held shakers, and over-the-row machines) in terms of workers’ postural loads and self-reported discomfort using ergonomics intervention techniques. Five field studies in the western region of the United States between 2017 and 2018 were conducted using the Borg CR10 scale, electromyography (EMG), Rapid Upper Limb Assessment (RULA), the Cumulative Trauma Disorders (CTD) index, and the NIOSH (National Institute for Occupational Safety and Health) lifting equation. In evaluating the workloads of picking and moving blueberries by hand, semi-mechanical harvesting with hand-held shakers, and completely mechanized harvesting, only EMG and the NIOSH lifting equation were used, as labor for this system is limited to loading empty lugs and unloading full lugs. Based on the results, we conclude that working on the fully mechanized harvester would be the best approach to minimizing worker loading and fatigue. This is because the total component ratio of postures in hand harvesting with a RULA score equal to or greater than 5 was 69%, indicating that more than half of the postures were high risk for shoulder pain. For the semi-mechanical harvesting, the biggest problem with the shakers is the vibration, which can cause fatigue and various risks to workers, especially in the upper limbs. However, it would be challenging for small- and medium-sized blueberry farms to purchase automated harvesters due to their high cost. Thus, collaborative efforts among health and safety professionals, engineers, social scientists, and ergonomists are needed to provide effective ergonomic interventions.

Forced Postures in Courgette Greenhouse Workers

“…In "Aerating soil" (bent back; Table 7), "Stringing" (both arms at or above shoulder level and standing or squatting on two bent legs; Table 7), "Harvesting" (bent back, standing or squatting on two bent legs, and standing or squatting on one bent leg; Table 7) and "Plant removal" (bent back and standing or squatting on two bent legs; Table 7) something similar happens, but with risk levels between 2 and 3. These disorders and other incorrect postures of the trunk, wrist, and neck have also been described by other authors [12,[25][26][27][28][29][30].…”

Harvest of Southern Highbush Blueberry with a Modified, Over-The-Row Mechanical Harvester: Use of Handheld Shakers and Soft Catch Surfaces

“…However this semi-mechanical harvesting system is not practical for large-scale blueberry growers who make up the majority of blueberry acreage in the United States. Operators of handheld shakers encountered repetitive motion, awkward and/or sustained postures, prolonged standing and vibration which can cause fatigue and various risks to their upper limbs [12].…”

“…Takeda et al [11] found that harvesting blueberries with handheld shakers in conjunction with a portable, soft catch surface frame resulted in less bruise damage than commercial OTR harvesters. However, the ergonomics of using unsupported, handheld shakers while standing on the ground was a concern as the weight, vibration and extended use could lead to musculoskeletal disorders and, without any mechanical fruit conveyance system on the portable harvesting frame, the overall harvest efficiency did not improve over hand harvesting [11,12].In 2017, further tests were conducted in Florida, California, Oregon, and Washington to harvest blueberries with an OTR harvester (Oxbo 7240, Oxbo International, Lynden, WA USA) with several key modifications: (1) a platform with two heights was installed on each side of the OTR harvester between the front and rear wheel wells for human operators to stand on and work the shaker while looking down at the bush, (2) the handheld shakers were suspended from the overhead frame of the OTR harvester. The shaker to be operated from the higher platforms had a 1-m-long handle and the shaker to be operated from the lower platforms had a 0.5-m-long handle, (3) the hard polycarbonate catch plates were replaced with soft fruit catch plates [13] on one side of the harvester by the harvester manufacturer, and (4) intermediate soft sheets were installed over the rigid conveyor as described in a recent companion article by DeVetter et al [14].…”

“…Takeda et al [11] found that harvesting blueberries with handheld shakers in conjunction with a portable, soft catch surface frame resulted in less bruise damage than commercial OTR harvesters. However, the ergonomics of using unsupported, handheld shakers while standing on the ground was a concern as the weight, vibration and extended use could lead to musculoskeletal disorders and, without any mechanical fruit conveyance system on the portable harvesting frame, the overall harvest efficiency did not improve over hand harvesting [11,12].…”

Repetitive Movements in Melon Cultivation Workers under Greenhouses

“…Its objective is to improve and adapt the workplace/environment to people [6]. Musculoskeletal disorders (MSDs) can arise in all types of activities, tasks, or sectors [7]: Agriculture [8,9], health [10,11], industry [12,13], education [14,15], etc.…”