Ergonomic study and product intervention for Indian local farmers

Ergonomic study -

Indian local Farmers

By Manas Deobhankar

Index 1. Introduction 2. Literature review 2.1 Summary 2.2 Aim and Objective 3. Methodology 3.1 Task Observed 3.2 Inclusion/Exclusion criteria 3.3 Task analysis 3.4 Nordic Questionnaire 3.5 Body map with VAS 3.6 REBA 3.7 QEC 3.8 Tools 3.8.1 Tools checklist 3.8.2 Anthropometric measurement 3.9 Strength assessment 4. Concept Exploration 4.1 Concept sketches 4.2 Concept details (Material, dimensions) 4.3 Prototypes 5. Conclusion/Future Scope

01

Introduction India is primarily an agrarian economy as farming is one of the most important occupations in the country. It is generally perceived as a healthy outdoor occupation.

However numbers of studies have classified farming as a risky and hazardous job. Musculoskeletal disorders (MSDs) are increasingly recognized as a significant hazard of agricultural occupation. According to the International Labor Organization (ILO), around 160 million work-related illnesses per year occur around the world, in which work-related musculoskeletal disorders (WMSDs) have a prominent role in terms of occupational health and also economics.

Farming being a physically laborious occupation, inevitably places farm workers at potential risk of musculoskeletal disorders such as osteoarthritis (OA) of the hip and knee, low back pain (LBP), neck and upper limb complaints, and hand–arm vibration syndrome. There are various risk factors related to farming activities which may contribute to the development of musculoskeletal disorders among farmers. Some of these occupational risk factors include static positioning, forward bending, heavy lifting and carrying, kneeling, and vibration.

According to Agriculture census of India (2011) about 70% of rural households of India still depend primarily on agriculture for their livelihood.Thus there is a need for study of prevalence of MSDs in farmers of India and necessity of ergonomic intervention.

02

Literature Review A review of literatures related to ergonomics in agriculture in India was performed and the selected papers where categorised into following categories: (1) Investigating the causation and prevalence of MSDs among the farmers.

(2) Design of ergonomically interventions (3) Anthropometric surveys collecting anthropometric measuremnets of farmers in different areas.

Summary: (1) There is variation in discomfort region as per nature of crop evidently from the difference in nature of posture adapted or repetitive movement done by the farmers (2) Four most common musculoskeletal disorders affecting the farmers : lower back pain; knee pain, shoulder pain, and neck pain.

(3) Poor postures adapted for and lack of ergonomic awareness in the farming community are the two principal causative factors contributing to the development of MSDs. 03

Literature Review (4) Discomfort due to farming activities is significantly higher in women farmers than male farmers due to added responsibilities performing numerous household activities.

(5) Various ergonomically designed interventions suggested and tested keeping in view the anthropometric data of farmers in consideration.

04

Aim and objectives Aim: to investigate the causation of discomfort related to working postures and to assess the work related musculoskeletal disorder among the farmers of Loni-Kalbhor, Maharashtra.

Objectives : (1) to determine the prevalence of work related musculoskeletal disorders (WMSDs) in local farmers of Loni-Kalbhor, Maharashtra (2) to analyse the causation of discomfort resulting from awkward and stressful postures due to various repetitive tasks performed by farmers

05

Methodology This study was undertaken in the month of March, when the ploughing and sowing of the fields was completed. The tasks performed by farmers that were observed : (1) Composting (2) Weeding (3) Reaping (4) Watering The tasks observed were predominantly performed on ccrops of green leafy vegetables like – Spinach, fenugreek and mint

06

Tools Used The Artifact model is an object model describing the realization of use cases, and serves as an abstraction of the implementation model and its source code. The design model is used as essential input to activities in implementation and test.

Datal Khurpi

Koyta

Kudal 07

Selection Criteria -

Women Farmers

Inclusion criteria : - Women farmers - Women are the backbone of the development of rural and national economies. They comprise 43% of the world’s agricultural labor force, which rises to 70% in some countries.

- Farmers with farming as a primary occupation, with a minimum experience of 5 years.

- Farmers cultivating leafy vegetables.

Exclusion criteria : - Excluding other male farmers - Excluding farmers with no self owned good supply system - Farmers with automation for performing the tasks (for example water pump with pipelines for watering) - Farmers cultivating grains, fruits.

08

Time Motion Analysis

Why? Reaping

Task no A1 A2 A3 A4 A5 A6 A7 A8 A9

Task name Reaping vegetables Uproo�ng vegetables Weeding vegetables Watering the farm Sowing seeds Collec�ng vegetables Packing into bags Loading tempo Cleaning the tools

Time study is a direct and continuous observation of a task, using a timekeeping device (e.g., decimal minute stopwatch, computer-assisted electronic stopwatch, and videotape camera) to record the time taken to accomplish a task.

Uprooting

Time mo�on analysis Avg. �me to complete (In hrs.)

2 to 3 2 to 3 2 to 3 2 to 3 1 1 2 to 3 1 to 2 1

Watering

Frequency of task (Times/week) 2 to 3 2 to 3 2 to 3 1 to 2 1 2 to 3 2 to 3 2 3 to 4

Total Time (In hrs./week) 4 to 9 4 to 9 4 to 9 2 to 6 1 2 to 3 4 to 9 2 to 4 3 to 4

09

Time Motion Analysis Tasks

Repe��ve (R) or not?

(NR) R

Equipment

Ac�ons Performed in task

Cycle length

Barehands/tool used - khurup

3 sec

TASK B: Manual uproo�ng(reaping) squa�ng

R

Barehands/tool used - khurup

Phase 1: Bending to reach the unwanted weeds Phase 2: Uproo�ng the weed by one hand Phase 3: Collec�ng the weeds in other hand Phase 1: Reach the crops in squa�ng posture

TASK C: Manual reaping(bending)

R

Koyta

TASK D: Manual watering – (bending)

R

Kudal

TASK A: Manual uproo�ng (weeding) bending

Phase 2: Uproo�ng by double hand opera�on alternately in same posture Phase 3: Tying the bundle Phase 4: Keeping the bundle on the ground Phase 1: Bending to reach the crops to reap Phase 2: Cu�ng off the crop with sharp tool, repeated thrust.

Phase 3: Collec�ng the crops at a place Phase 4: Packing crops in a bag Phase 3: Li�ing and carrying bag to truck Phase 1: Ploughing the water dam by bending, repeated thrusts Phase 2: Building the dam on the other side

Frequency of cycle (sec) 20 per minute

Total dura�on throughout day

40 sec

1.5 per minute

120 min – 180 min

40 sec

1.5 per minute

120 min – 180 min

60 sec

1 per minute

120 min – 180 min

120 min – 180 min

10

N

ordic Musculoskeletal Questionnaire

The analysis and detection of musculoskeletal symptoms of different individuals in different parts of the planet using indirect methods requires the standardization of the evaluation questions Therefore, Kuorinka and his team developed the NMQ with the support of the Nordic Council of Ministers.

The questions in the questionnaire are forced choice variants and may be either self-administered or used in interviews. They concentrate on symptoms most often encountered in an occupational setting. The reliability of the questionnaires has been shown to be acceptable. Specific characteristics of work strain are reflected in the frequency of responses to the questionnaires.

NMQ was administered by interviewing a total of 20 participants (8 men and 12 women) farmers were randomly selected from the village of Loni-Kalbhor, Maharashtra.

Physical characteristics

Mean

± S.D.

Age (yrs)

37.1

± 7.6

Height, cm

158.7

± 8.3

Weight, kg

54.15

± 10.6

6.5

± 1.2

2.1

± 0.8

16.5

± 7.8

Duration of work per day (hours) Duration of rest per day (hours) Years of Experience

Physical And Physiological Characteristics Of The Subjects

11

N

ordic Musculoskeletal Questionnaire

Results

Insights (1)

Lower back pain experienced by the workers in last 7 days was

significantly associated with t he type of task performed and the type of posture in which the task is performs.

(2)

Lower back pain and neck pain experienced by farmers in last 12 months

was significantly positively associated height of the farmer.

(3)

Experience was not significantly associated with any of the discomfort

area maybe due to the fact that the farmers have become habitual to the discomfort/pain.

(4)

Though most of the farmers experienced discomfort in different areas,

they deny to have been reduced the amount of work. When asked for the reason, the farmers agreed to have no other option.

12

B

ody map with VAS

`The Visual Analog or Analogue Scale with Body Map was designed to present to the respondent a rating scale with minimum constraints.

Respondents mark the location on the 10-cm line corresponding to the amount of pain they experienced after a task performed associated with the body part marked on the body map. This gives them the greatest freedom to choose their pain's exact intensity. It also gives the maximum opportunity for each respondent to express a personal response style. The VAS frame measures exactly 10 cm. The distances from zero to the markings in cm are result indicators to be processed as continuous variables for statistical analysis.

As in NMQ, it was found that the discomfort/pain experienced by farmers was corelated to the type of task performed, Body map with VAS was used for further insights.

Three of the tasks :Weeding, Reaping and watering was mostly carried out in two postures Squatting and bending - with repetitive hand gestures.

Posture - Squa�ng

BEFORE

AFTER

Posture – Bending (reaping)

BEFORE

AFTER

Lower back

2.2

5.1

Neck

0.9

2.3

Ankles

0.5

1.2

Knees

1.5

2.1

Lower back

2.7

4.9

Neck

0.7

2.9

Ankles

1.2

1.9

Knees

2.3

3.7

Calves

0.4

0.9

Calves

2.1

4.6

Wrist (right)

1.2

1.8

Wrist (right)

1.3

1.9

Shoulder (right)

0.6

2.1

Posture – Bending (watering)

BEFORE

AFTER

Lower back

2.3

4.9

Neck

0.5

1.2

Ankles

0.3

0.4

Knees

0.9

1.3

Calves

0.6

0.8

Wrist (right)

0.9

2.2

Shoulder (right)

1.2

4.5

13

Rapid Entire Body Assessment Rapid Entire Body Assessment (REBA) method was applied for postural analysis of work related musculoskeletal risk factors. REBA (Rapid Entire Body Assessment) was developed by Hignett, S. and McAtamney, to provide a quick and easy observational postural analysis tool for whole body activities (static and dynamic giving musculoskeletal risk action level. The development of REBA is aimed to divide the body into segments to be coded individually with reference to movement planes. It provides a scoring system for muscle activity caused by static, dynamic, rapid changing or unstable postures. It reflects that coupling is important in handling of the loads but may not always be via the hands. It also gives an action level with an indication of urgency.

REBA Employee Assessment Worksheet A. Neck, Trunk and Leg Analysis Step 1: Locate Neck Position

+1

2

+2

Step 7a: Adjust…

If shoulder is raised: +1 If upper arm is abducted: +1 If arm is supported or person is leaning: -1

Step 2: Locate Trunk Position +1 +2

+4

+1

+1

4

Step 5: Add Force/Load Score

Step 10: Look-up Posture Score in Table B

Using values from steps 7-9 above, locate score in Table B

7

Step 11: Add Coupling Score

Well fitting Handle and mid rang power grip, good: +0 Acceptable but not ideal hand hold or coupling acceptable with another body part, fair: +1 Hand hold not acceptable but possible, poor: +2 No handles, awkward, unsafe with any body part,

Posture Score A

+

If load < 11 lbs. : +0 If load 11 to 22 lbs. : +1 If load > 22 lbs.: +2 Adjust: If shock or rapid build up of force: add +1 Force / Load Score

0

Step 6: Score A, Find Row in Table C

Add values from steps 4 & 5 to obtain Score A. Find Row in Table C.

Unacceptable: +3

=

7

Step 12: Score B, Find Column in Table C

Add values from steps 10 &11 to obtain Score B. Find column in Table C and match with Score A in row from step 6 to obtain Table C Score.

Score A

Scoring

1 = Negligible Risk 2-3 = Low Risk. Change may be needed.

4-7 = Medium Risk. Further Investigate. Change Soon.

8-10 = High Risk. Investigate and Implement Change 11+ = Very High Risk. Implement Change

+2

2

Step 9a: Adjust…

If wrist is bent from midline or twisted : Add +1

Add +2

Using values from steps 1-3 above, Locate score in Table A

1

Wrist Score

Leg Score

Step 4: Look-up Posture Score in Table A

+2

Step 9: Locate Wrist Position:

Trunk Score

Step 3: Legs Adjust:

2 Upper Arm Score

Lower Arm Score

3

Add +1

+4

Step 8: Locate Lower Arm Position:

+3

Step 2a: Adjust…

If trunk is twisted: +1 If trunk is side bending: +1

+2

+2

+3

Step 1a: Adjust…

If neck is twisted: +1 If neck is side bending: +1

+1

Date: 24/03/17

Neck Score

+2

+2

Reaping

Step 7: Locate Upper Arm Position:

+2

+1

Task Name:

B. Arm and Wrist Analysis

Scores

7 Table C Score

+

1 Activity Score

=

8 REBA Score

2 Posture Score B

+

0

Coupling Score

=

2 Score B

Step 13: Activity Score

+1 1 or more body parts are held for longer than 1 minute (static) +1 Repeated small range actions (more than 4x per minute) +1 Action causes rapid large range changes in postures or unstable base

Original Worksheet Developed by Dr. Alan Hedge. Based on Technical note: Rapid Entire Body Assessment (REBA), Hignett, McAtamney, Applied Ergonomics 31 (2000) 201-205

From above sheet, score 8 suggest high risk of awakward posture.

14

Rapid Entire Body Assessment REBA Employee Assessment Worksheet A. Neck, Trunk and Leg Analysis

+1

2

+2

Step 7a: Adjust…

If shoulder is raised: +1 If upper arm is abducted: +1 If arm is supported or person is leaning: -1

Step 2: Locate Trunk Position +1 +2

+4

+1

+1

4

Step 9a: Adjust…

If wrist is bent from midline or twisted : Add +1

Add +2

Using values from steps 1-3 above, Locate score in Table A

Step 5: Add Force/Load Score

Using values from steps 7-9 above, locate score in Table B

Well fitting Handle and mid rang power grip, good: +0 Acceptable but not ideal hand hold or coupling acceptable with another body part, fair: +1 Hand hold not acceptable but possible, poor: +2 No handles, awkward, unsafe with any body part,

+

+

0

Coupling Score

Unacceptable: +3

=

6

Step 12: Score B, Find Column in Table C

Score A

6 Table C Score

+

1 Activity Score

Score B

Step 13: Activity Score

7

=

=

2

Add values from steps 10 &11 to obtain Score B. Find column in Table C and match with Score A in row from step 6 to obtain Table C Score.

Scoring

1 = Negligible Risk 2-3 = Low Risk. Change may be needed.

4-7 = Medium Risk. Further Investigate. Change Soon.

8-10 = High Risk. Investigate and Implement Change 11+ = Very High Risk. Implement Change

Posture Score B

Step 11: Add Coupling Score

Posture Score A

0

Add values from steps 4 & 5 to obtain Score A. Find Row in Table C.

2

Step 10: Look-up Posture Score in Table B

6

If load < 11 lbs. : +0 If load 11 to 22 lbs. : +1 If load > 22 lbs.: +2 Adjust: If shock or rapid build up of force: add +1 Force / Load Score

Step 6: Score A, Find Row in Table C

2

+2

Wrist Score

Leg Score

Step 4: Look-up Posture Score in Table A

1

Step 9: Locate Wrist Position:

Trunk Score

Step 3: Legs Adjust:

+2

Lower Arm Score

2

Step 2a: Adjust…

If trunk is twisted: +1 If trunk is side bending: +1

2 Upper Arm Score

Step 8: Locate Lower Arm Position:

+3

Add +1

+4

+3

Step 1a: Adjust…

If neck is twisted: +1 If neck is side bending: +1

+2

+2

Neck Score

+2

+1

Date: 24/03/17

Step 7: Locate Upper Arm Position:

+2

+2

Uprooting

B. Arm and Wrist Analysis

Scores

Step 1: Locate Neck Position

+1

Task Name:

+1 1 or more body parts are held for longer than 1 minute (static) +1 Repeated small range actions (more than 4x per minute) +1 Action causes rapid large range changes in postures or unstable base

REBA Score

Original Worksheet Developed by Dr. Alan Hedge. Based on Technical note: Rapid Entire Body Assessment (REBA), Hignett, McAtamney, Applied Ergonomics 31 (2000) 201-205

From above sheet , score 7 suggest medium risk of awakward posture.

REBA Employee Assessment Worksheet A. Neck, Trunk and Leg Analysis

Step 7: Locate Upper Arm Position:

+2

+1

2

+2

+2

+4

+1

+1

2 Add +1

Step 5: Add Force/Load Score

Step 10: Look-up Posture Score in Table B

Using values from steps 7-9 above, locate score in Table B

6

Step 11: Add Coupling Score

Well fitting Handle and mid rang power grip, good: +0 Acceptable but not ideal hand hold or coupling acceptable with another body part, fair: +1 Hand hold not acceptable but possible, poor: +2 No handles, awkward, unsafe with any body part,

Posture Score A

+

If load < 11 lbs. : +0 If load 11 to 22 lbs. : +1 If load > 22 lbs.: +2 Adjust: If shock or rapid build up of force: add +1 Force / Load Score

0

Step 6: Score A, Find Row in Table C

Add values from steps 4 & 5 to obtain Score A. Find Row in Table C.

Unacceptable: +3

=

6

Step 12: Score B, Find Column in Table C

Add values from steps 10 &11 to obtain Score B. Find column in Table C and match with Score A in row from step 6 to obtain Table C Score.

Score A

Scoring

1 = Negligible Risk 2-3 = Low Risk. Change may be needed.

4-7 = Medium Risk. Further Investigate. Change Soon.

8-10 = High Risk. Investigate and Implement Change 11+ = Very High Risk. Implement Change

2

Step 9a: Adjust…

If wrist is bent from midline or twisted : Add +1

Add +2

Using values from steps 1-3 above, Locate score in Table A

+2

Wrist Score

Leg Score

Step 4: Look-up Posture Score in Table A

1

Step 9: Locate Wrist Position:

Trunk Score

Step 3: Legs Adjust:

+2

Lower Arm Score

4

Step 2a: Adjust…

If trunk is twisted: +1 If trunk is side bending: +1

3 Upper Arm Score

Step 8: Locate Lower Arm Position:

+3

+2

+4

+3 Step 7a: Adjust…

If shoulder is raised: +1 If upper arm is abducted: +1 If arm is supported or person is leaning: -1

Step 2: Locate Trunk Position +1 +2

+1

+2

Neck Score

Step 1a: Adjust…

If neck is twisted: +1 If neck is side bending: +1

+2

Date:

B. Arm and Wrist Analysis

Scores

Step 1: Locate Neck Position

+1

Task Name:

8 Table C Score

+

2 Activity Score

=

10 REBA Score

4 Posture Score B

+

1

Coupling Score

=

5 Score B

Step 13: Activity Score

+1 1 or more body parts are held for longer than 1 minute (static) +1 Repeated small range actions (more than 4x per minute) +1 Action causes rapid large range changes in postures or unstable base

Original Worksheet Developed by Dr. Alan Hedge. Based on Technical note: Rapid Entire Body Assessment (REBA), Hignett, McAtamney, Applied Ergonomics 31 (2000) 201-205

From above sheet, score 9 suggest high risk of awakward posture.

15

Rapid Entire Body Assessment Ac�vity REBA Score Risk Level Task A – Manual up-roo�ng (weeding)- Bending Phase 1: Bending to reach 11 Very high the unwanted weeds

Ac�on category

Phase 2: Uproo�ng the weed by one hand

12

Very high

Necessary urgent- Work must cease un�l a safer solu�on can be found

Phase 3: Collec�ng the weeds in other hand

9

high

Ac�on needs to be taken very soon

Very high

Necessary urgent- Work must cease un�l a safer solu�on can be found Necessary urgent- Work must cease un�l a safer solu�on can be found

Task B- Uproo�ng (reaping)- squa�ng Phase 1: Reach the crops in 12 squa�ng posture Phase 2: Uproo�ng by 12 double hand opera�on alternately in same posture Phase 3: Tying the bundle 6

Very high

Phase 4: Keeping the bundle on the ground

8

high

Further considera�on should be given as to how risk can be lowered Ac�on needs to be taken very soon

Ac�vity

REBA Score

Risk Level

Ac�on category

Very high

Necessary urgentWork must cease un�l a safer solu�on can be found

Task C – Manual reaping - Bending Phase 1: Bending to reach 11 the crops to reap

Medium

Necessary urgentWork must cease un�l a safer solu�on can be found

Phase 2: Cu�ng off the crop with sharp tool, repeated thrust.

Phase 3: Collec�ng the crops at a place

12

Very high

Necessary urgent- Work must cease un�l a safer solu�on can be found

9

high

Ac�on needs to be taken very soon

Phase 4: Packing crops in a bag

4

medium

Further inves�ga�on, change soon

Phase 3: Li�ing and carrying bag to truck

13

Very high

Necessary urgent- Work must cease un�l a safer solu�on can be found

Very high

Necessary urgent- Work must cease un�l a safer solu�on can be found

Very high

Necessary urgent- Work must cease un�l a safer solu�on can be found

Task D- Manual watering - Bending Phase 1: Ploughing the 12 water dam by bending, repeated thrusts Phase 2: Building the dam on the other side

12

16

Quick Exposure Checklist

Why?

Quick exposure checklist tool is very easy to use. It provides exposure scores for body areas. QEC helps to identify needed exposure reduction. It assists with job comparisons as well as before and after evaluations.

Khanchan Choudhari

24/03/17

Khanchan Choudhari

24/03/17

4

4

6

4

4

4

6

6

8

4

4 4 1

4

4 6

4

1

6

6 4

6 24

26

24

4

Exposure levels for back, shoulder, wrist and neck are at high exposure.

And for driving, vibration, work pace and stress it is at moderate level.

Sangita Kunwar

Sangita Kunwar

24/03/17

4

4

6

6

24/03/17

4

8

6

4

12

4

4 4 1

4

4 6

6

1

6

6 4

6 24

26

24

4

Exposure levels for back, shoulder, wrist and neck are at high exposure.

And for driving, vibration, work pace and stress it is at moderate level.

Quick Exposure Checklist Laxmi Kalbhor

Laxmi Kalbhor

24/03/17

12

8

8

6

24/03/17

6

8

6

6

14

8

6 8 1

6

6 10

10

1

8

6 4

8 34

40

30

9

Exposure levels for back, shoulder, wrist and neck are at high exposure. And for driving, vibration, work pace and stress it is at moderate level.

Exposure levels

Insights - QEC scores for squatting as well as bending postures having vary high risk factor which are related to back, shoulder, wrist, neck.

- And for driving, vibration, work pace and stress it is at moderate level.

18

Tools Checklist No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22

Ques�ons

Tool Is the material of the handle easy for grip?

Is the tool equiped with handle that has a grip diameter suitable for most workers?

Does the tool handle have a slippery surface?

Is the handle long enough for your hand?

Does the handle or other parts of tools are damadged?

Does the tool contain sharp edges?

Do you store tools in dry, secure place?

Is the tool evenly balanced?

Handling Is the handle comfortable to hold?

Is the tool heavy to hold, bulky?

Is it managabled size handle?

Do you use glove while using the tool?

Does your arm posi�on goes above waist while using this tool?

Does the use of tool is repeta�ve in working scenario?

Working posture Are both hands needed to hold this tool?

Is your wirst in an awakward posi�on while working?

Do you need to bend while using this tool?

Does the tool need squa�ng posi�on to operate?

Do you feel pain while working con�nuously with tool?

Yes

No

N/A

Is there any twisted posi�on while working with any tool?

Maintenance Do you clean every tool a�er working?

Do you use clean water to clean tools?

19