A comparative study of the effectiveness of photogrammetric versus manual anthropometric measurements.

BACKGROUND: The accurate measurement of the human body is essential when it comes to designing agricultural tools and equipment that can effectively accommodate and interact with individuals when performing a task. The traditional method for measuring an individual's body measurements is highly complex and requires two or more skilled individuals and reliable measurement tools. Finding a new approach that is speedier, more precise, and less expensive than current methods is therefore necessary. OBJECTIVE: This study aims to develop an inexpensive novel photogrammetric anthropometric measurement setup that can extract the dimensions of an individual subject irrespective of their body shape. METHODS: This study involved the creation of a setup comprising four cameras for a 360° photoshoot of human subjects to calibrate and test the developed measurement setup for capturing photos of human subjects and compare the results with manual measurements. RESULTS: Ten different body dimensions were measured using the setup. There was a significant correlation between the manual and photogrammetric measurement methods (0.943 < r < 0.997). The highest absolute error recorded was 1.87%. CONCLUSION: The photogrammetric method for collecting anthropometric data is a reliable substitute for manual measurements across diverse populations. The results indicate that this low-cost approach is highly precise and reliable, with strong correlation to manual measurements. Multiview photogrammetry proves effective for individuals of various body shapes, making it a versatile option for data collection.

Noise exposure and hearing loss among tractor drivers in India.

BACKGROUND: Tractors emit high intensity noise and prolonged exposure to high intensity noise causes hearing loss to the drivers. OBJECTIVE: The aim of this study was to measure noise intensity at the tractor drivers' ear level and hearing loss among tractor drivers. METHODS: Noise intensity was measured on 6 models of tractors which were operated with 5 different tillage implements. In order to assess hearing loss, audiometric test was performed at 7 frequencies, i.e. 250, 500, 1000, 2000, 4000, 6000, and 8000 Hz, among 30 tractor drivers and 30 control group subjects. All the selected tractor drivers and control group subjects were also interviewed to obtain personal information and noise exposure details. RESULTS: The tractor drivers were exposed to noise intensity in the range of 91.7-97.5 dB(A). Audiogram analysis shows that the hearing threshold levels were significantly (p < 0.05) higher among the tractor drivers as compared with the control group subjects. The effect was significantly (p < 0.05) more on the left ear as compared with the right ear among the tractor drivers. Increase in age has significant (p < 0.05) effect on the hearing threshold levels on the left ear. Prevalence of high frequency hearing loss was 50% among tractor drivers as compared with 10% among control group subjects. Hearing loss was significantly (p < 0.05) more in the low frequency as compared with the high frequency among the tractor drivers. CONCLUSION: Indian tractor operators are exposed to high noise levels which may result in hearing loss. It is recommended that hearing conservation programs should be initiated to prevent noise hazards and hearing loss among the tractor drivers.

An investigation of the hand anthropometric database of agricultural workers and integration of the database into tools and protective gear designs.

BACKGROUND: The hand anthropometric data is the baseline for design of hand tools and equipment. OBJECTIVE: This study aimed to generate the hand anthropometric database of male and female agricultural workers and compare it with the hand anthropometric data of other regions of India. The use of collected data is illustrated to design hand tools and protective gear. METHODS: Hand anthropometric data were collected from 228 male and 198 female agricultural workers of northeast India. A total of 35 hand dimensions, stature and body mass from different tribes in the age group of 18-60 years were precisely measured. Measured data were statistically analysed to study the effects of gender, ethnicity, and age on hand dimensions. Correlation coefficients were determined among hand dimensions and linear regression equations were developed between highly correlated dimensions. RESULTS: The results show that all hand dimensions of the male and female subjects are significantly different (p < 0.01). Most of the hand dimensions were significantly different (p < 0.05) among different tribes for the male subjects. However, less number of hand dimensions were significantly different among tribes for the female subjects. Age of the subjects has significant effects (p < 0.01) on dimensions related to thickness, depth and circumference of fingers. The use of these data in the ergonomic design of hand tools and personal protective gear is illustrated to increase safety and comfort as well as efficiency of operators. CONCLUSION: There is a difference in the hand dimensions of different tribes of northeast India. This needs to be considered when designing agricultural hand tools and equipment.

Isometric push and pull strengths of agricultural workers from Northeast India.

BACKGROUND: In agricultural farming operations, the incompatibility between operators' physical capability and labor demands in the operation of tools and equipment results in a decreased performance, productivity, and safety related measures. OBJECTIVE: The aim of this study was to collect a biomechanical database of push/pull strengths for initiating the development of a human-centered design of equipment that is not available for the intended user group, i.e. Nagaland. METHODS: The sample consisted of 399 male and 271 female agricultural workers from the five districts of Nagaland, aged 18 to 65 years, classified into three age groups. In the process of push and pull force measurements, the elbow angle of the participants were set to 30-120°, 120-130°, and 130-180°. All tests were performed in triplicates with a resting period of two minutes between every consequent recording. RESULTS: The results showed that isometric push and pull strength values (Mean±SD) for males were 18.91±4.67 kg and 17.98±3.97 kg respectively and 13.07±4.06 kg and 11.98±3.33 kg for females respectively. The results of independent samples from student's t-test demonstrate that there was a substantial variance in the isometric push and pull strength values (p < 0.05) between the genders across the various age spectrum. CONCLUSIONS: With ageing, muscular strength for push-pull strength in males and females reduce. The study reports that the recommended value of male and female isometric push-pull strength for agricultural workers of Nagaland should be 5th percentile of female data i.e. 6.40 and 1.71 kg respectively.

Nonfatal agricultural work-related injuries: A case study from Northeast India.

BACKGROUND: Occupational injuries are a major problem in agriculture worldwide. In the Northeast region of India, most of the farm operations are carried out manually with hand operated tools and equipment. These tools also cause some nonfatal accidents. In the absence of reliable data on accidents in this region, injury prevention policy cannot be madeOBJECTIVE:The aim of this study was to survey injury causing agricultural accidents occurring during 2010 to 2013 in Arunachal Pradesh of the northeast region to know their magnitude, causes and severity. PARTICIPANTS: In this study, four districts of Arunachal Pradesh namely Papum Pare, Lower Subansiri, West Siang and East Siang were chosen using purposive sampling. From each district, 15 villages were selected. In these villages, a total of 50614 agricultural workers participated and 174 and 48 injuries were found for male and female workers respectively. METHOD: A case-control study was carried out in Arunachal Pradesh. The questionnaire-based approach was used for data collection. The questionnaire contains detailed information on the demographic and injury characteristics. The Demographic information included gender, age, educational background, etc. and injury characteristics included the nature of the injury, the body part injured, and type of tools and equipment that caused the injury. RESULTS: The results showed that farm tools and equipment-related accidents were maximum i.e. 144 (60%) caused due to dao followed by 19 from spade (8%), 18 from sickle (7%) and 8 from axe (3%). The foot and legs were the most frequently injured body parts. From this study, it was also revealed that male agricultural workers are more affected as compared to their female counterparts. CONCLUSIONS: Agricultural accident incident rate (AIR) was found to be 589 per 1,00,000 workers per year. The AIR for males is 462 per 100,000 workers per year which is 3.6 times higher than female workers. The root causes of accidents are the use of traditional tools and equipment in various agricultural activities. Therefore, any ergonomic interventions in designing tools and equipment will significantly improve the occupational health and safety of workers.

Impact of ergonomic intervention in manual orange harvester among the workers of hilly region in India.

BACKGROUND: Manual orange harvesting is very laborious, time consuming and unsafe operation whereas neither mechanical harvesting nor mechanized hand harvesting is possible in north-east India due to its hilly terrains. The awkward postures and repetitive nature of work in orange harvesting, demands a comfortable and appropriate hand harvester for hilly region. OBJECTIVE: The purpose of this study was to develop a manual orange harvester for hilly regions considering the ergonomic parameters, and compare the performance with the existing models of the manual harvester. PARTICIPANTS: In this study twenty healthy experienced orchard workers (10 male and 10 female) participated who did not have any previous functional musculoskeletal disorders. METHODS: We developed a manual orange harvester by eliminating the problems associated with the existing harvesters. The developed model along with existing models was evaluated extensively in the field. During evaluations, heart rate of the subjects was measured and oxygen consumption was predicted to calculate the energy expenditure rate (EER) from the established relationship in the laboratory before the field experiments. Further, performance parameters of orange harvester i.e. plucking rate (PR), damaged quantity (DQ), plucking energy requirement (PER) and discomfort rating were also observed. RESULTS: The PR was 425, 300 and 287 pieces per hour for the developed model (DM), first existing model (EM1) and second existing model (EM2), respectively. The DM showed lower PER (2.14 kJ/piece) followed by EM2 (2.95 kJ/piece) and EM1 (4.02 kJ/piece) which is considered as overall performance as it includes energy per unit of plucking. Further, the body part discomfort score revealed that DM was more comfortable in use followed by EM2 and EM1. CONCLUSIONS: The performance of the DM was found better in terms of plucking rate, energy requirement and body part discomfort than the other existing models. Shoulders and neck are the most affected body parts where all subjects felt severe discomfort.