Paddy is the main crop of Orissa, grown in both the Kharif and Rabi seasons. Beating paddy bundles over a wooden or stone surface is the most common method of threshing, seen in most part of Orissa. Pedal threshers are now beginning to replace the age-old beating method, as animal power is scarce after the super cyclone. During field surveys several types of pedal thresher injuries were recorded, due to the impact of grain flung at high speed at the eyes, face and nose of the operator.
Fifteen female subjects in the age group of 18 to 45 in Orissa University of Agriculture & Technology (OUAT) central farm were selected on the basis of the anthropometrics data for above study. Their heart rate, blood pressure, maximum aerobic power and oxygen consumption were measured in the laboratory at rest and work. The maximum aerobic power of the selected female subjects was observed to be in the range of 1.56 to 1.81 l min-1, which decreases with the increase in age of the subjects. The body mass index was observed to be in the range of 18.4 to 22.4 kg/m2. Oxygen consumption rate at rest was in the range of 0.16 to 0.23 l min-1, which also decreases as the age of the subject increases. Average working oxygen consumption rate was noted to be in the range of 0.86 to 0.91 l min-1 for all workers. The corresponding average working heart rate was found to be in the range of 123 to 139 bpm for female workers. The work pulse was found to be in the range of 52.0 to 66.7 bpm for above female agricultural workers.
Maximum continuous working time for female agricultural workers observed to be 49 minutes operated by double workers against 34 minutes by single worker. Number of strokes per minute for female worker was noticed in the range of 95 to 104. The output of the thresher was observed to be 32 to 40 kg /hr.
Based on the ergonomics study, anthropometric data and feedback received from the subjects, it is recommended to operate the thresher with double worker instead of single operator for higher efficiency, less drudgery and fatigue.
1. There are two major cropping seasons in India, namely, Kharif and Rabi. The Kharif season is during the south-west monsoon (July-October). During this season, agricultural activities take place both in rain-fed areas and irrigated areas. The Rabi season is during the winter months, when agricultural activities take place only in the irrigated areas.
2. The cyclone of 29-30 October 1999 resulted in significant loss of life, damaged 1828532 houses, 1810091 hectares of agriculture land and significant infrastructure damage affecting one third population of the state. The UN agencies along with governmental and non-governmental agencies are actively supporting the state in the relief and rehabilitation programs
3. Santosh Kumar Mohanty, Ph.D., is an assistant professor in the Department of Farm Machinery and Power, College of Agricultural Engineering and Technology, Orissa University of Agriculture and Technology
4. This paper was submitted to the Applied Ergonomics Conference 2006
Source: Dr. S K Mohanty
This article originally appeared in The Ergonomics Report™ on 2007-04-19.