TITLE:
Operations of Knapsack Sprayer and Its Impacts on Physiological Parameters of Selected Operators
AUTHORS:
Bukola Olanrewaju Afolabi, Akinfoye Oyime Daniel Adejumo, Ayoade Oladele Atere, Titus Adeyinka Ilori
KEYWORDS:
Cumulativetrauma, Knapsack Sprayer, Operational Effect, Physiological Changes, Stroke
JOURNAL NAME:
Engineering,
Vol.15 No.2,
February
9,
2023
ABSTRACT: The study was aimed at determining the impacts of operating Manually
Operated Hand Lever Knapsack Sprayers (MOHLKS) on physiological responses of
the operators as dependent on anthropometric variations and sex. Twenty eight
subjects, (4 female, 24 male) Mean ± SD: Age 22.5 ± 1.92, 24.29 ± 2.2 years;
Body Mass Index 24.6 ± 4.8, 21.7 ± 2.4 kg/m2 were employed in the study. Selected anthropometric parameters of weight and
height were used to determine body mass index (BMI), with these are arm-reach
forward, elbow to fingertip, hand length and hand width were measured to
establish human variations in diversity. Subjects undertook the operation at 5
replicates each, before and after which
information about operators’ body pain locations and body physiological changes
of heart rates were obtained. Measured parameters were used in the
determination of expended energy (EE), physiological cost (PC), oxygen
intake (VO2) and aerobic power (VO2max). Alongside with
these were operational parameters of stroke, pace and time taken to get the
operation done and environmental factors of temperature and relative humidity.
The results revealed on the average that the BMI (24.61 ± 4.78 kg/m2)
in female operators was higher, this corresponded to PC and VO2,
while the VO2max (34.83 ± 3.30 ml/min/kg) in males is higher. More
EE was obtained in female subjects (3.53 ±
3.76 kCal/min) as compared to male subjects (3.42 ± 7.48 kCal/min). The
main effects plot of operational factors on EE displayed the stroke made by the
subjects during spraying operation as parameter with largest effect on EE.
Regression equation for EE and PCI is given as PCI = 1.97 + 25.2 EE, while the
P-value at α = 0.05 is
0.000 and R2 = 98.8%. Post operational body pain showed that 19 out
of 28 subjects incurred at least one type of body pain, with shoulder pain as
most frequent. The results of the study suggest that early incidence of fatigue
may occur in female operators as compared to the males, and in addition,
cumulative trauma at shoulder, back, and
upper and lower arm may result over time. Hence, it is recommended that the
tank volume should be reduced and the straps for the shoulders should be
supported with additional cushion.