Barrier free HDB kitchen design for wheelchair users

The analyzed aspects involved: 1 minimum width of the different kitchen layouts; 2 minimum width of a wall with doors; 3 area; 4 shape and 5 location of sink, cooker, refrigerator, washi

BARRIER-FREE HDB KITCHEN DESIGN FOR WHEELCHAIR

USERS

Vol I

XIE HONGYAN (B.E (Hons.), Xi’an Jiaotong University, China)

A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF ARTS (ARCH.)

DEPARTMENT OF ARCHITECTURE NATIONAL UNIVERSITY OF SINGAPORE

2003

Dedicated to my beloved family

Great appreciation goes also to Mr Liem Andre, my supervisor towards the end of my candidature, for his kind regard during my whole research process, his valuable advice and critical comments on this thesis

My appreciation should also extend to Dr Pinna Indorf, for her critical insights, which helped

me to focus and direct my research

My thanks also go to all the people who have participated in the pilot anthropometric studies

of the elderly persons and wheelchair users in this thesis

Great thanks to Judy Wee, the president of the Handicaps Welfare Association; Mr Subrata Banerjee, the Manager of the Rehabilitation Centre, Handicaps Welfare Association; Mr Li Muyan, the manager of the Singapore Buddhist Lodge; and Ms Miaoye Without their help, the anthropometric studies presented here would not have been possible

I am also deeply grateful to the owners of the investigated kitchens, for their hospitality and kindness

I also wish to thank my CASA friends, who helped me during hard times and made my life at NUS enjoyable

Last but not least, thanks to my beloved parents and family, who have always supported and cared for me Without their love, this endeavor would lack any meaning

SUMMARY

Barrier-free kitchen is imperative for disabled persons, especially when they live independently For a wheelchair user, he/she may face many barriers to use a kitchen This research investigates the physical barriers to wheelchair users in small home kitchens in Singapore

The objectives of this research are mainly three:

1) To identify the primary barriers (on the physical aspect) for wheelchair users in small HDB kitchens

2) To understand the current situations of and reasons for these barriers

3) To give recommendations for barrier-free kitchen design

First, through the literature review and field investigation of some kitchens used by wheelchair users, the primary physical barriers were identified It was found that the barriers could be roughly classified into two categories: one was highly related with the wheelchair user’ reach and the height of the appliances; the other was highly related with the turning spaces and kitchen layouts

Second, a pilot study on the wheelchair user’s reach was conducted on 32 wheelchair persons The purpose of this study was to know the rough reach range of the wheelchair users and then how the kitchen could be designed according to their reach range and body dimensions The study results were used to design the mock-up kitchens

Third, the layouts of the HDB kitchens from 1978-1999 were analyzed according to the

Singapore, NKBA and ADA Guidelines (Building and Construction Authority, 2002;

Peterson, 1998; Kearney, 1995) The analyzed aspects involved: (1) minimum width of the different kitchen layouts; (2) minimum width of a wall with doors; (3) area; (4) shape and (5) location of sink, cooker, refrigerator, washing machine and clothes drying From the schematic analysis, some recommendations were derived for the barrier-free kitchen design

Finally, based on the measuring results of the wheelchair user’s reaches and the schematic analysis, three kitchens were designed True scale kitchen mock-ups were built and 12 wheelchair users were chosen to test the kitchens During the testing, the kitchens were improved and tested once more

From the tests, one “Optimum small kitchen” (area is 9.6m2) and one “Minimum small kitchen” (area is 7.4 m2) were derived It was also found that in the existing guidelines recommendations were unavailable on some important issues such as the approaching space to

a refrigerator and the different requirements of different types of wheelchair users These issues should be further investigated in future and recommendations provided There were also some recommendations derived from the research on the detailed design of the barrier-free kitchen

LIST OF ACRONYMS

ADA – Americans with Disabilities Act

ADLs – Activities of Daily Living

ANSI – American National Standard Institute

HDB – Housing and Development Board

HWA – Handicaps Welfare Association

ICF – International Classification of Functioning, Disability and Health

NKBA – National Kitchen & Bath Association (USA)

PWD – Public Works Department

SDD – Scottish Development Department

UFAS – Uniform Federal Accessibility Standards

UNESCAP – United Nation Economic and Social Commission for Asia and the Pacific URA – Urban Redevelopment Authority

TABLE OF CONTENTS

VOLUME I

ACKNOWLEDGEMENTS I SUMMARY II LIST OF ACRONYMS IV TABLE OF CONTENTS V LIST OF FIGURES X LIST OF TABLES XIV

CHAPTER I INTRODUCTION 1

1.1 Background 1

1.2 Research Objectives 3

1.3 Research Methodology 3

1.4 Research Scope 7

1.4.1 Scope of the Wheelchair Users 7

1.4.2 Scope of the Barriers in Kitchen 7

1.4.3 Scope of the Operations and Appliances in HDB Kitchens for Wheelchair Users 8

CHAPTER II LITERATURE REVIEW 9

2.1 Concepts of the Disability, Accessible, Persons with Disabilities and Wheelchair Users 9

2.2 History of Barrier-free Design 9

2.3 Barrier-free Design in Singapore 9

2.4 Literature Review of the Established Codes, Guidelines, and Related Researches 10

CHAPTER III IDENTIFYING THE PRIMARY BARRIERS FOR WHEELCHAIR USERS IN HDB KITCHENS 12

3.1 Selection of Kitchens Used by Wheelchair Users 12

3.2 Observations 13

3.2.1 Floor 13

3.2.2 Countertop 14

3.2.3 Wall Cabinet and Corner Cabinet 14

3.2.4 Ventilation Hoods, Sockets and Switches 15

3.2.5 Washing Machine and Clothes Drying 15

3.3 Floor Plan of the Five Kitchens 15

3.4 Summary 17

CHAPTER IV VERTICAL DESIGN OF KITCHENS 18

4.1 Subjects 19

4.2 Method for Taking Measurements 20

4.3 Data Statistics 21

4.4 Measurement Results and Discussion 24

4.4.1 Upward Reach 24

4.4.2 Up-forward Reach to a Wall 25

4.4.3 Down-forward Reach to a Wall 25

4.4.4 Downward Reach Laterally 26

4.4.5 Forward Reach over a Table 26

4.4.6 Lateral Reach over a Table 29

4.4.7 Knee Height, Wheelchair Armrest Height and Countertop Height 29

4.4.8 Summary of the Reach 33

4.5 Accessible Cabinets 33

4.6 Clothes Washing and Drying 34

CHAPTER V FLOOR PLAN DESIGN OF SMALL KITCHENS FOR WHEELCHAIR USERS 36

5.1 Dimensions for Graphic Analysis 36

5.1.1 Approaching Spaces at Doors 37

5.1.1.1 Door width 38

5.1.1.2 Approaching spaces at doors 38

5.1.1.3 Tests at HWA 39

5.1.2 Turning Space for Wheelchair Users 42

5.1.2.1 Tests at HWA 44

5.1.3 Minimum Width of the Different Kitchen Layouts 46

5.1.4 Minimum Width of a Wall with Doors 49

5.1.5 Clear Floor Space for a Wheelchair User at Appliances 51

5.2 Setting up the Database of Kitchen and the Criteria for Graphic Analysis 52

5.2.1 Setting up the Database of Kitchen 53

5.2.2 Setting the Criteria for Graphic Analysis 55

5.3 Floor Plan Analyses of the HDB Kitchens 55

5.3.1 Basic Area Requirement 55

5.3.1.1 Kitchen analyses 56

5.3.2 Kitchen Shapes 57

5.3.2.1 Kitchen analyses 59

5.3.3 Place of Sink and Cooker 60

5.3.3.1 Cooking process and routes 61

5.3.3.2 Limitation 64

5.3.3.3 Place of Sink and Cooker 65

5.3.4 Place of Refrigerator 66

5.3.4.1 Refrigerator’s place related to the sink and cooker 66

5.3.4.2 Refrigerator’s door direction and landing space 66

5.3.5 Place of Washing Machine and Clothes Drying 68

5.3.5.1 Location of washing machine 68

5.3.5.2 Clothes drying 68

CHAPTER VI TESTS ON BARRIER-FREE KITCHEN DESIGNS 73

6.1 The Optimum Small Kitchen Designed for Test 73

6.1.1 Floor Plan Design of the Optimum Small Kitchen 73

6.1.2 Vertical Design of the Optimum Small Kitchen 76

6.2 Two Minimum Small Kitchen Designed for Test 78

6.2.1 The First Design 79

6.2.2 The Second Design 81

6.3 Setting up Kitchen Mock-ups 84

6.4 Test Scenarios 87

6.5 Test Procedure 87

6.6 Subjects 88

6.7 Test Results of the Optimum Small Kitchen Design (Kitchen O1) 89

6.7.1 Scenario 1 89

6.7.1.1 Approaching from door to refrigerator to sink 89

6.7.1.2 How to carry items 97

6.7.1.3 Working at the sink and cooker 98

6.7.1.4 Space 99

6.7.2 Scenario 2 100

6.7.3 Scenario 3 106

6.7.3.1 Cabinet near the cooker 106

6.7.3.2 Rotating cabinet 108

6.7.3.3 Cabinet beside the refrigerator 109

6.7.3.4 Wall cabinet 111

6.7.3.5 Storage 111

6.7.4 Scenario 4 112

6.7.5 Modifications of Kitchen O1 113

6.8 Test Results of the First Modified Design of Kitchen O1 (Kitchen O1m1) 115

6.8.1 Approaching from Door to Refrigerator to Sink 116

6.8.2 Approaching the Microwave Oven 117

6.8.3 Using the Microwave Oven 118

6.8.4 Washing Machine 119

6.8.5 Storage 120

6.8.6 Sink 120

6.9 Test Results of the Second Modified Design of Kitchen O1 (Kitchen O1m2) 120

6.9.1 Approaching from Door to Refrigerator to Sink 120

6.9.2 Approaching the Microwave Oven 122

6.9.3 Using the Microwave Oven 124

6.9.4 Washing Machine 125

6.9.5 Rotating Cabinet 126

6.9.6 Storage 127

6.10 Test Result of the First Minimum Small Kitchen Design (Kitchen M1) 127

6.10.1 Scenario 1 127

6.10.1.1 Approaching from door to refrigerator to sink 127

6.10.2 Scenario 2 131

6.10.3 Scenario 3 133

6.10.4 Scenario 4 133

6.10.5 Modifications of Kitchen M1 133

6.11 Test Results of the Modified Design of Kitchen M1 (Kitchen M1m1) 134

6.11.1 Approaching from Door to Refrigerator to Sink 135

6.11.2 Approaching and Using the Microwave Oven 135

6.11.3 Washing Machine 136

6.11.4 Storage 136

6.12 Test Result of the Second Minimum Small Kitchen Design (Kitchen M2) 137

6.12.1 Scenario 1 137

6.12.1.1 Approaching from door to refrigerator to sink 137

6.12.2 Scenario 2, Scenario 3 and Scenario 4 140

6.12.3 Modifications of Kitchen M2 140

6.13 Test Results of the Modified Design of Kitchen M2 (Kitchen M2m1) 141

6.13.1 Approaching from Door to Refrigerator to Sink 141

6.13.2 Approaching and Using the Microwave Oven 142

6.13.3 Washing Machine 142

6.14 Summary and Findings 143

6.14.1 The “Optimum Small Kitchen” and the “Minimum Small Kitchen” 147

6.14.2 Approaching Methods to a Refrigerator 149

6.14.3 Approaching Methods to a Sink or Cooker 151

6.14.4 Approaching Methods to a Microwave Oven 153

6.14.5 Two Solutions of Making Countertops at the Same Height 155

6.14.6 Routes from Door to Refrigerator to Sink to Cooker, then from Sink to Microwave Oven 156

6.14.7 Cabinet 157

6.14.8 Washing Machine 158

CHAPTER VII CONCLUSION 165

7.1 Important Findings and Recommendations 165

7.1.1 Primary Physical Barriers 165

7.1.2 Reaches and Countertop Height Determination 166

7.1.3 Approaching Spaces at Doors 169

7.1.4 Tests on Turning Spaces 170

7.1.5 Minimum Width of the Different Kitchen Layouts and Minimum Width of a Wall with Doors 170

7.1.6 Optimum Small Kitchen and Minimum Small Kitchen 172

7.1.7 Approaching Space to a Refrigerator 174

7.1.8 Location of Refrigerator in Relation to the Living Room Door, Sink and Cooker 175

7.1.9 Types of Wheelchair Users 176

7.1.10 Other Findings 176

About refrigerator: 176

About countertop: 177

About microwave oven: 177

About cabinet: 178

About washing machine and clothes drying pole: 180

7.2 Research Contribution 180

7.3 Application of the Kitchen Shape 181

7.4 Research Limitation 182

7.5 Future Directions 183

BIBLIOGRAPHY 185

VOLUME II APPENDIX 1 SCOPE OF OPERATIONS AND THE APPLIANCES IN HDB KITCHENS 1

APPENDIX 2 CONCEPTS OF THE DISABILITY, ACCESSIBLE, PERSONS WITH DISABILITIES AND WHEELCHAIR USERS 3

APPENDIX 3 HISTORY OF BARRIER-FREE DESIGN 4

APPENDIX 4 OBSERVATIONS IN THE FIVE INVESTIGATED KITCHENS 6

APPENDIX 5 ANTHROPOMETRY PRINCIPLES 14

APPENDIX 6 METHODS FOR MEASURING THE REACHES 17

APPENDIX 7 ANTHROPOMETRIC DATA OF THE 32 WHEELCHAIR USERS

(TABLES) 20

APPENDIX 8 ANTHROPOMETRIC DATA OF THE 16 MALE WHEELCHAIR USERS 23

APPENDIX 9 ANTHROPOMETRIC DATA OF THE 16 FEMALE WHEELCHAIR USERS 29

APPENDIX 10 ANTHROPOMETRIC DATA OF THE 32 WHEELCHAIR USERS 35

APPENDIX 11 KNEE HEIGHT 40

APPENDIX 12 ACCESSIBLE CABINETS 43

APPENDIX 13 APPROACHING SPACES AT DOORS 45

APPENDIX 14 SPACE FOR WHEELCHAIR TURNING 48

APPENDIX 15 MINIMUM WIDTH OF THE DIFFERENT KITCHEN LAYOUTS 51

APPENDIX 16 CLEAR FLOOR SPACE FOR A WHEELCHAIR USER AT APPLIANCES 58

APPENDIX 17 DEVELOPMENT OF HDB FLATS AND KITCHENS 61

APPENDIX 18 KITCHEN DATABASE 66

APPENDIX 19 AREA CRITERION FOR CHOOSING KITCHEN 72

APPENDIX 20 EXAMPLES OF SCHEMATIC ANALYSIS ABOUT THE KITCHEN AREA 75

APPENDIX 21 EXAMPLES OF SCHEMATIC ANALYSIS ABOUT THE KITCHEN SHAPE 81

APPENDIX 22 EXAMPLE OF SCHEMATIC ANALYSIS ABOUT THE BAD LOCATION OF A SINK 84

APPENDIX 23 METHOD FOR ROUTE TESTING 85

APPENDIX 24 REFRIGERATOR’S PLACE RELATED TO THE SINK AND COOKER 87

APPENDIX 25 EXAMPLE OF SCHEMATIC ANALYSIS ABOUT THE REFRIGERATOR DOOR AND LANDING SPACE 89

APPENDIX 26 PLACE OF WASHING MACHINE AND CLOTHES DRYING 90

APPENDIX 27 KITCHEN LAYOUT ANALYSES 93

APPENDIX 28 TEST SCENARIOS 134

APPENDIX 29 OBSERVATIONS AND QUESTIONS IN TESTING KITCHEN O1M1 136

APPENDIX 30 OBSERVATIONS AND QUESTIONS IN TESTING KITCHEN O1M2 137

APPENDIX 31 OBSERVATIONS AND QUESTIONS IN TESTING KITCHEN M1M1 138

APPENDIX 32 OBSERVATIONS AND QUESTIONS IN TESTING KITCHEN M2M1 139

APPENDIX 33 TEST RESULTS OF THE MOCK-UP KITCHENS 140

LIST OF FIGURES

Figure 1 1: Research framework 6

Figure 3 1: Floor layout plan of Kitchen No 1 16

Figure 3 2: Floor layout plans of Kitchens No 2 16

Figure 3 3: Floor layout plans of Kitchens No 3 16

Figure 3 4: Floor layout plan of Kitchen No 4 17

Figure 3 5: Floor layout plan of Kitchen No 5 17

Figure 4 1: Freezer in the wheelchair user’s reach 24

Figure 4 2: Estimation of the wall cabinet height 28

Figure 4 3: The countertop height is decided by the appliance thickness, knee height and armrest height 30

Figure 4 4: Different types of the wheelchair 31

Figure 4 5: Small ancillary countertops below the main countertops 33

Figure 4 6: Top-loaded washing machine and front-loaded washing machine 34

Figure 4 7: Device for easy clothes drying 35

Figure 5 1: Different approaching methods at doors 39

Figure 5 2: The first approaching method to a door 40

Figure 5 3: The third approaching method to a door 41

Figure 5 4: The second approaching method to a door 41

Figure 5 5: Wheelchair’s fore-wheel was beyond the line 42

Figure 5 6: More space is needed on the latch side of the door 42

Figure 5 7: Turning radius based on different pivot points 43

Figure 5 8: Turning in a small circle turning space 44

Figure 5 9: Turning in a large circle turning space 44

Figure 5 10: Turning in a T-shaped space 44

Figure 5 11: Minimum width of the kitchen 50

Figure 5 12: A clear floor space at appliances 52

Figure 5 13: Kitchen layout to suit a wheelchair user 56

Figure 5 14: Traffic area 59

Figure 5 15: Two routes for instant noodle making in Kitchen 8182-11 62

Figure 5 16: Lengths of the two routes in each kitchen layout 63

Figure 5 17: A cooker should not be placed too near a window or a door 65

Figure 5 18: Refrigerator placement considerations 67

Figure 6 1: Plan of the “Optimum small kitchen” 74

Figure 6 2: A-A section of the “Optimum small kitchen” 77

Figure 6 3: B-B section of the “Optimum small kitchen” 77

Figure 6 4: The first design of the “Minimum small kitchen” 79

Figure 6 5: The second design of the “Minimum small kitchen” 82

Figure 6 6: The mock-up of the “Optimum small kitchen” 84

Figure 6 7: The mock-up of the first “Minimum small kitchen” 84

Figure 6 8: The mock-up of the second “Minimum small kitchen” 85

Figure 6 9: The door of the microwave oven could only be opened at 90o 85

Figure 6 10: The inner shelves were made in the refrigerator and rotating cabinets 86

Figure 6 11: The pull-out countertop was made 86

Figure 6 12: The height of inner barrel of the washing machine was simulated 86

Figure 6 13: The wooden props and counter legs could be adjusted 86

Figure 6 14: The three kitchen designs were modified into four kitchens 88

Figure 6 15: The route of a subject from door to refrigerator to sink 89

Figure 6 16: Process of a subject approaching from door to refrigerator to sink 90

Figure 6 17: The left half and right half of the refrigerator 91

Figure 6 18: The route from door to refrigerator to sink 91

Figure 6 19: The process of a subject approaching from door to refrigerator to sink 92

Figure 6 20: The route of a subject approaching from door to refrigerator to sink 93

Figure 6 21: Process of a subject approaching from door to refrigerator to sink 94

Figure 6 22: The route of a subject approaching from door to refrigerator to sink 95

Figure 6 23: Process of a subject approaching from door to refrigerator to sink 96

Figure 6 24: The wheelchair users easily collided with the cabinets when approaching the refrigerator backward 97

Figure 6 25: A wheelchair user dragged the bowl along the countertop 97

Figure 6 26: Sink and cooker with knee space could be comfortably used by the wheelchair users 98

Figure 6 27: Cutting the object on the main countertop 99

Figure 6 28: The ventilation hood could be reached by all subjects 99

Figure 6 29: Frontward approach from the sink to the microwave oven 100

Figure 6 30: Backward approach was easier for the wheelchair users who preferred to use the right hand 101

Figure 6 31: For the wheelchair user who preferred to use the right hand, the microwave oven on his/her left was very difficult to use 101

Figure 6 32: The microwave oven used by a wheelchair user who preferred to use his left arm 101

Figure 6 33: A subject who approached the microwave oven backward chose the countertop left to the microwave oven 102

Figure 6 34: Either bending forward or turning the body was uncomfortable for the subjects 103

Figure 6 35: The subjects had to move the food round the door 103

Figure 6 36: The bowl could be put on the countertop when a subject was opening or closing the microwave oven’s door 103

Figure 6 37: The wider pull-out countertop will make shifting a bowl easier 104

Figure 6 38: Shifting a bowl from microwave oven to the countertops beside 104

Figure 6 39: A step between the main countertop and the pull-out countertop 105

Figure 6 40: The microwave oven at the edge of the main countertop 105

Figure 6 41: Approaching the cabinet, utilizing the knee space 106

Figure 6 42: Approaching the cabinet at an angle 107

Figure 6 43: Approaching the cabinet laterally 107

Figure 6 44: Three approaching methods to the cabinet near the cooker 107

Figure 6 45: The handles installed at the right side of the drawers could be more easily accessed 108

Figure 6 46: Approaching the rotating cabinet where it was on the user’s left 108

Figure 6 47: Approaching the rotating cabinet where it was on the user’s right 109

Figure 6 48: Two approaching methods to the rotating cabinet 109

Figure 6 49: Two approaching methods to the cabinet right to the refrigerator (photos) 110

Figure 6 50: Two approaching methods to the cabinet right to the refrigerator 110

Figure 6 51: The handles installed at the left side of the drawers could be more easily accessed 111

Figure 6 52: A subject using a wall cabinet 111

Figure 6 53: Approaching methods to the washing machines 112

Figure 6 54: Approaching methods to the washing machine and the preferred locations of the clothes hanging pole 112

Figure 6 55: The subjects’ preference of the clothes pole 113

Figure 6 56: Layout of the first modified design of Kitchen O1 (Kitchen O1m1) 114

Figure 6 57: The second improved design of Kitchen O1 (Kitchen O1m2) 115

Figure 6 58: The knee space made it easier for the subject to open the refrigerator door and get the object 116

Figure 6 59: The route from door to refrigerator to sink when the knee space was utilized 116

Figure 6 60: The bowl could be put on the countertop left to the refrigerator 117

Figure 6 61: The approaching route from the sink to the microwave oven 118

Figure 6 62: A subject using the microwave oven 119

Figure 6 63: The raised washing machine was easy to use 119

Figure 6 64: Approaching route from door to refrigerator to sink 121

Figure 6 65: Process of a subject approaching from door to refrigerator to sink 122

Figure 6 66: Different approaching methods from sink to microwave oven 123

Figure 6 67: Process of a subject using the microwave oven 124

Figure 6 68: Approaching methods to the washing machine and the preferred locations of the clothes hanging pole 125

Figure 6 69: Two approaching methods to the rotating cabinet 126

Figure 6 70: A subject using the rotating cabinet with the left hand 126

Figure 6 71: A subject using the rotating cabinet with the right hand 126

Figure 6 72: Route of the subjects who preferred to use the right hand 127

Figure 6 73: Route of the subjects who preferred to use the right hand 128

Figure 6 74: Process of a subject approaching from door to refrigerator to sink 129

Figure 6 75: Route of the second approaching method used by the subjects who preferred to use the left hand 130

Figure 6 76: Process of a subject approaching from door to refrigerator to sink 130

Figure 6 77: The process of a subject who used the microwave oven 132

Figure 6 78: When a subject sat laterally and the microwave oven was on his right, it was difficult for him to put the bowl to the countertop left to the microwave oven 132

Figure 6 79: Layout of the modified design of Kitchen M1 (Kitchen M1m1) 134

Figure 6 80: Route of the subjects approaching from door to refrigerator to sink when the knee space was utilized 135

Figure 6 81: The washing machine could be used by different approaching methods 136

Figure 6 82: Different approaching methods to the washing machine and the preferred locations of the adjustable clothes pole 136

Figure 6 83: The route from door to refrigerator to sink 137

Figure 6 84: Process of a subject approaching from door to refrigerator to sink 138

Figure 6 85: Route of the subjects from door to refrigerator to sink 139

Figure 6 86: Process of a subject approaching from door to refrigerator to sink 139

Figure 6 87: Layout of the modified design of Kitchen M2 (Kitchen M2m1) 140

Figure 6 88: Route of the subjects approaching from door to refrigerator to sink when the knee space was utilized 141

Figure 6 89: Route of the subjects approaching from the door to refrigerator to sink 142

Figure 6 90: Different approaching methods to the washing machine and the preferred locations of the adjustable clothes pole 143

Figure 6 91: Layout of Kitchen O1m3 148

Figure 6 92: Layout of Kitchen M1m2 149

Figure 6 93: Some space should be provided at both sides of the refrigerator 151

Figure 6 94: The first solution of making countertops at the same height 155

Figure 6 95: The second solution of making countertops at the same height 156

Figure 7 1: (Left) adjustable wall cabinet; 168

Figure 7 2: Different approaching methods at doors 169

Figure 7 3: More space is needed on the latch side of the door 169

Figure 7 4: Minimum width of a wall with doors 172

Figure 7 5: An Optimum small kitchen design (Kitchen O1m3) 173

Figure 7 6: A Minimum small kitchen design (Kitchen M1m2) 173

Figure 7 7: Space for approaching a refrigerator 175

Figure 7 8: locations of the door, refrigerator, sink and cooker 175

Figure 7 9: Two solutions of making countertops at the same height 178

Figure 7 10: Handles on the side from which a wheelchair user is approaching 179

Figure 7 11: (Left) knee space for wheelchair users who are good with the left hand or both hands (Right) knee space for wheelchair users who are good with the right hand or both hands 179

Figure 7 12: Situations in irregular shaped kitchens can be very complex 181

Figure 7 13: The “Optimum small kitchen” example can be adapted to several irregular shaped kitchens 182

LIST OF TABLES

Table 3 1: Five investigated kitchens for wheelchair users 12

Table 3 2: Floor level changes in the five kitchens 13

Table 3 3: Changes in floor level 13

Table 3 4: Heights of the countertops in the five kitchens 14

Table 3 5: Heights of the bottoms of the wall cabinets 14

Table 3 6: Heights of the ventilation hoods 15

Table 4 1: Age distribution of the subjects 19

Table 4 2: Ethnic distribution of the subjects 19

Table 4 3: The health conditions of the subjects 19

Table 4 4: Comparison between the observations, illustrations, measurement results and their applications 23

Table 4 5: Values of the down-forward reach to a wall and downward reach laterally 26

Table 4 6: Values of the forward reach over a table and lateral reach over a table 29

Table 4 7: Measurement results of the knee height 30

Table 4 8: Measurement result of the wheelchair armrest height 30

Table 4 9: Recommendations for the kitchen design for wheelchair users 33

Table 5 1: Time spent in different methods 40

Table 5 2: Recommendations on the turning space 43

Table 5 3: Time spent in three different turning spaces 45

Table 5 4: The minimum width for different kitchen layouts 48

Table 5 5: Recommendations about the clear floor space 51

Table 5 6: Microsoft Access can list data according to different enquiries 54

Table 5 7: Shapes of HDB kitchens from 1978 to 1999 58

Table 5 8: Lengths of the two routes in each kitchen layout 63

Table 5 9: Summary of the observations, recommendations and applications 72

Table 6 1: The wheelchair users selected for the test 88

Table 6 2: Scenario test results in the seven kitchens 146

Table 6 3: Different approaching methods for different wheelchair users 150

Table 6 4: Different approaching methods for different wheelchair users 152

Table 6 5: Different approaching methods for different wheelchair users 154

Table 6 6: Routes of the different types of wheelchair users in different kitchen layouts 164

Table 7 1: Reaches of the wheelchair users 166

Table 7 2: Recommendations for the kitchen design used by wheelchair users 167

Table 7 3: The recommended minimum width for different kitchen layouts 171

CHAPTER I INTRODUCTION

1.1 Background

As Singapore grows in maturity, attitudes toward disability have been gradually changed Singaporeans adopted the fundamental philosophy that the disabled should be treated as equal members of society

There is no comprehensive survey of the number of disabled people in Singapore, though the number is expected to be many According to UN Economic and Social Commission for Asia and the Pacific (UNESCAP) (1995), The Central Registry of Disabled People (CRDP) of the Ministry of Community Development in Singapore recorded only persons with permanent disabilities The total number of registered disabled people in 1988 was 12,526, less than 0.5 per cent of the total population This percentage was much smaller compared to those of Japan, United States, or Canada According to Harrison (1988), this was probably because of the different classification criteria employed and absence of strong incentives for registration Therefore, the figures may not represent the actual number of persons with disabilities, which may be more than the official figures It may be assumed that a more realistic figure would be 67,000 in 1988 (UNESCAP, 1995)

Because the population of disabled people in Singapore is unignorable, it is important to design an environment catering for their needs Kitchen is important element of the home environment where many tasks include washing, cooking, and sometimes eating are performed

A disabled person may face many barriers in such space if the kitchen is unable to meet their special requirements

A barrier-free kitchen benefits a disabled person whether he/she lives with his/her family or independently When a disabled person lives with his/her family, of course, his/her family can cook for him/her But a barrier-free kitchen can provide him/her the opportunity to share the

cooking pleasure; thus, this affords him/her self-confidence, dignity and a sense of achievement Undoubtedly, when a disabled person lives independently, a barrier-free kitchen

is necessary

High-rise, high-density housing is the first and majority choice for the population in Singapore where land is precious (Lam, 1988) The Housing and Development Board (HDB) is the sole national authority responsible for physical planning and implementation of public housing Over 86% of the total population lives in housing produced by the HDB About 78 percent of these dwellings are owner-occupied (HDB, 1998)

As one of the large groups in disabled people, wheelchair users usually face some barriers According to Goldsmith (1976), the wheelchair user is handicapped in three aspects

“Firstly, whatever condition put him in the wheelchair; the disabilities concerned will

be handicapping in themselves Secondly, he must operate at an eye-level which is some 400 mm lower than that of standing people, which is disadvantageous both physically and psychologically Thirdly, he rolls around in a cumbersome, awkward, space consuming, distinctive and inelegant vehicle Whilst the first handicap is outside the designer’s control, the second and third relate to the traditional ergonomic considerations of reach, working level, clearance and access-as such they are potentially soluble.”

Kitchens in HDB flats are designed according to certain principles For example, they are designed not too big, usually attached to a bathroom (Wong and Yeh, 1985) The arrangement

of other rooms also influences a kitchen’s floor shape Some HDB kitchens were built in irregular shapes (HDB, 1977-1999) For these reasons, a wheelchair user who lives in an HDB flat may face some barriers in the kitchen

This research focused on the understanding of the primary barriers for wheelchair users in small HDB kitchens, how the barriers arise and how they can be solved/avoided The findings will add depth to our understanding of the interactions between wheelchair users and the kitchen Such an understanding can then help in the creation of supportive home spaces for wheelchair users in future

1.2 Research Objectives

The objectives of this research are mainly three:

1) To identify the primary barriers (on the physical aspect) for wheelchair users in small HDB kitchens

2) To understand the current situations of and reasons for these barriers

3) To give recommendations for barrier-free kitchen design

1.3 Research Methodology

There were roughly three steps to the research methodology used The first step was a literature review and field investigation The main aim of this step was to identify the primary barriers for the wheelchair users in HDB kitchens Related knowledge, principles and guidelines were found through reference, such as books, journals, newspaper articles, reports and papers presented in conferences Field investigations provided more specific information about the present, local conditions of the kitchens used by wheelchair users in Singapore HDB flats They were necessary for identifying the primary barriers for wheelchair users in the local context After the barriers had been identified, the barriers were classified into two groups: one group was related to vertical design and user’s reach (such as the height of countertop, cabinet, handle, etc.), and the other group was related to the floor plan design (such as space for turning

a wheelchair, kitchen working center layouts, working routes, etc.) A survey on the scope of the operations and appliances in HDB kitchens for wheelchair users was also conducted The following analyses about the floor plan design were also confined by this survey results

The second step of the research was analyses of the physical layouts according to the two categories For the vertical design, this study mainly focused on two questions:

1) What is the reachable range of the wheelchair users?

2) What are the proper heights of the countertop and appliances for the wheelchair users?

Therefore, a pilot study on anthropometry of wheelchair users was conducted The purpose of this anthropometric study was to find out the approximate reach range of the wheelchair users and how the kitchen should be designed according to their reach range and body dimensions There were 16 male and 16 female wheelchair users whose body dimensions and reach range were obtained at the Handicaps Welfare Association (HWA) Based on the measurement results, the suitable heights of the countertop, wall cabinets, appliances, handles, switches and

so on were estimated The results were applied to the vertical design of the mock-up test kitchens

With regard to floor plan design, the main discussions were about the rational area and layouts

of the HDB kitchens from the viewpoint of the barrier-free design for wheelchair users There were three possible methods of carrying out the kitchen floor plan analysis The first was to utilize floor plan drawings for floor plan analysis The second was to construct an experimental kitchen where layouts could be adjusted and rearranged Wheelchair users would be invited to test the kitchen and in the process, found out barriers in various conditions The third was to select existing HDB kitchens for floor plan analysis The third method was impracticable due

to the following constraints: (1) it was difficult to select suitable kitchens for sampling because there were many different kitchen types around the whole island; (2) the owner had to agree to allow tests carried out in his/her kitchen; (3) wheelchair users had to be taken to the kitchen for tests The first method was first chosen for general analyses of the existing kitchen plans It has the advantage of analyzing kitchen types in Singapore comprehensively The layouts of the 28 HDB kitchens from 1978-1999 were analyzed by applying three guidelines which are:

• The Code on Barrier-Free Accessibility in Buildings, 2002 (Building and Construction

Authority, 2002) (abbreviated as Singapore Guidelines in this thesis)

• The National Kitchen & Bath Association Presents, Universal Kitchen & Bathroom

Planning: Design That Adapts to People (Peterson, 1998) (abbreviated as NKBA Guidelines in this thesis)

• The ADA (Americans with Disabilities Act 1990) in Practice (Kearney, 1995)

(abbreviated as ADA Guidelines in this thesis)

The analyzed aspects involved: (1) area requirement; (2) kitchen shape; (3) place of sink and cooker; (4) place of refrigerator; (5) place of washing machine and clothes drying From the schematic analyses, some recommendations were derived for the barrier-free kitchen design The analyses showed that the area for the “optimum small kitchen” should be around 9m2; rectangular shape, which is not too narrow, is well suitable to arrange kitchen appliances The analyses also showed that there were some requirements on the location of the sink, cooker, refrigerator, washing machine and clothes drying All these findings were applied to the floor plan design of the mock-up test kitchens

The third step of the research methodology was to test the barrier-free kitchens newly designed After the general analyses of the existing kitchen plans, three barrier-free kitchens were designed Then the second method was used to test the kitchen examples Mock-ups were built in true scale at HWA 12 wheelchair users took part in the experiment There were 4 scenarios tested in each kitchen After the three mock-up test kitchens had been tested, they were modified based on the users’ comments Then the modified kitchens were tested again During the testing, supporting surveys were also conducted Finally, findings were summarized and the recommendations were given The research framework is illustrated in Figure 1.1

vertical design and floor plan design

Vertical design Floor plan design

Reaches Countertop height

4 Down-forward reach

to a wall

5 Downward reach laterally

6 Lateral reach over a table

1 Area requirement 2 Kitchen shape

3 Place of sink and cooker 4 Place of refrigerator 5 Place for washing machine and clothes drying

Turing space for wheelchair users

Approaching space to doors

Tests in HWA

28 HDB kitchens (1978-1999)

Recommendations on the vertical design

Recommendations on the floor plan design

Three kitchen examples:

in HDB kitchens for wheelchair users

Conclusions and recommendations

Floor space at appliance

1 Minimum width of the different kitchen layouts

2 Minimum width of a wall with doors

1.4 Research Scope

1.4.1 Scope of the Wheelchair Users

People use wheelchairs for many different reasons Some do so because of a sudden change or

an accident that takes away their ability to walk For others, it is because of inner diseases No matter how a person became a wheelchair user, in this thesis, only those who were able to move wheelchairs by themselves were involved as research subjects Some wheelchair users had serious diseases that did not allow them to propel the wheelchairs by themselves They were not involved in this thesis

1.4.2 Scope of the Barriers in Kitchen

There are different types of barriers They can be generated from physical, social and attitudinal world to impact on the wheelchair user’s performance According to Goldsmith

(1997), “by the social version of disability, … disabled people are those who are disabled on account of social barriers, by societal institutions which exclude them, and by the apparatus of architectural and other impediments which place them at a disadvantage.” The social version

of disability can cause disabilities in employment, education, transport and so on

However, this thesis mainly investigated the barriers in the physical aspect rather than the social aspect Among the physical barriers, some barriers were highly related to the user’s cognition For example, inadequate illumination or ambiguous indications on appliances could cause barriers to the user These cognitive barriers were not considered in this thesis

The space scope of the barriers was the kitchen The boundary consisted of the kitchen walls and doors Other rooms linking to the kitchen were not discussed

1.4.3 Scope of the Operations and Appliances in HDB Kitchens for Wheelchair Users

Many operations can be conducted in a kitchen There are also varied appliances used in a kitchen In order to identify the important operations and appliances accommodated in HDB kitchens for wheelchair users, a survey was conducted at HWA (for details please see Appendix 1: Scope of Operations and the Appliances in HDB Kitchens) It was found that cooking and laundry are the most important operations in HDB kitchens Wheelchair users prefer to do light cooking The sink, cooker, refrigerator and washing machine are the most often used appliances in HDB kitchens A microwave oven is often used in the kitchen Therefore, in this thesis the operations conducted in a kitchen were strictly limited to cooking and laundry The basic appliances were limited to a sink, cooker, refrigerator, microwave oven and washing machine

CHAPTER II LITERATURE REVIEW

2.1 Concepts of the Disability, Accessible, Persons with Disabilities and

2.2 History of Barrier-free Design

The barrier-free movement began in 1950s in response to demands by disabled veterans and advocates for people with disabilities to have opportunities in education and employment From the 1950s to the 1960s, along with the growing awareness of the need of accessibility, a number of states in USA set up their own accessibility standards (Story et al., 1998) In 1990

the Americans with Disabilities Act (ADA) was passed, and guidelines were passed in 1991

(Kearney, 1995) Equal rights are ensured in employment, access to places of public accommodation, services, programs, public transportation and telecommunications For details please see Appendix 3: History of Barrier-free Design

2.3 Barrier-free Design in Singapore

According to UNESCAP (1995), most of the recent developments in Singapore have been strongly influenced by market forces In recent years, a set of "Agendas for Action" had been proposed The purpose of the agendas was to look at aspects of Singaporean society which would benefit from a more "humane" form of social development Studies were conducted to assess the needs of minority groups

In April 1988, the Advisory Council on the Disabled was established under the purview of the Ministry of Community Development The mission of the organization is to create an environment with supportive facilities so that disabled people can develop their physical, mental, and social capabilities to the fullest extent (Council on Tall Buildings and Urban Habitat, 1992)

In 1989, the Code on Barrier-free Accessibility in Buildings (Public Works Department, 1990)

was issued It was revised in 1995 (Public Works Department, 1995) The latest version was issued in 2002 (Building and Construction Authority, 2002)

Under the Effort of the Urban Redevelopment Authority (URA) and the Public Works Department (PWD), some public spaces such as Streets, Buildings, Bus and MRT stations became more accessible

However, there seem to have been no published guidelines on designing kitchens for disabled people in Singapore Moreover, studies on this aspect are quite few No local studies on the barrier-free kitchen were found during the search for relevant literature

2.4 Literature Review of the Established Codes, Guidelines, and Related

Researches

A literature review was conducted on the barriers for wheelchair users in a kitchen (Donlan et al., 1978; Goldsmith, 1997; Grandjean, 1973; Conran, 1977; Peterson, 1998; Scottish Development Department, 1979) The literature shows that for wheelchair users, the barriers are quite similar The physical barriers are mainly in: steps at the door, too high countertops, lack of knee space, inaccessible cabinets and inaccessible switches/outlets

Some codes and guidelines were reviewed (American National Standard Institute, 1992; National Standard of Canada, 1995; British Standards Institution, 2000; Peterson, 1998; Kearney, 1995) Because the barrier-free kitchen design is closely related with the wheelchair users’ body dimensions and reaches, anthropometry and ergonomics theory and researches on the wheelchair users were reviewed (Batiste and Loy, 2002; Damon et al., 1971; Grandjean, 1973; Grandjean, 1988; Ham et al., 1998; Jarosz, 1996; Floyd et al., 1966) However, most of them are Western codes, guidelines and studies; thus, they cannot be directly applied to the

local context The only local code is The Code on Barrier-free Accessibility in Building, 2002

(Building and Construction Authority, 2002) But in this code, only a little information is available about the kitchen design for wheelchair users

CHAPTER III IDENTIFYING THE PRIMARY BARRIERS FOR WHEELCHAIR

USERS IN HDB KITCHENS

3.1 Selection of Kitchens Used by Wheelchair Users

Field investigations were conducted in order to acquire more information about the local HDB kitchens for wheelchair users Five wheelchair users, who live in HDB flats, were selected among clients of HWA in Singapore They were selected according to the rules that the participants more to be both male and female, old and young, fat and thin, and strong and weak

Investigations were conducted in the five kitchens; the subjects performed certain tasks in the kitchen following the investigator’s requests and the primary barriers encountered by the wheelchair users were recorded The investigated kitchens are listed in the Table 3.1

No

Owner’s Age and

gender Owner’s health status Flat type Kitchen area

Whether modified

2 38, female Paraplegia, fat 4-room flat 10.22m2 Unmodified

3 42, female Paralysis, thin 4-room flat 13.5m2 Unmodified

4 32, female Paraplegia, weak and thin 3-room flat

7.53 m2 (before modification) 14.9m 2 (after modification)

Modified

5 43, male Paraplegia, strong 3-room flat 15.69m2 Modified

Table 3 1: Five investigated kitchens for wheelchair users

Among the five kitchens, three of them (No.1, 2, 3) were ‘common’ ones which had not been modified Kitchen No 4 was newly built Its owner had to move into a new flat which is on a floor that the elevator can access after she had got handicapped; therefore, she had a chance to build the kitchen according to her needs The last kitchen (No.5) was modified after its owner had got handicapped; he stayed in his own flat because the elevator can access to the floor

The following is the summary of the observations in the five kitchens For the details please see Appendix 4: Observations in the Five Investigated Kitchens In order to make a comparison among the observations, recommendations in the literature and the measurement results of the reaches, the findings of the observations were also tabulated in Table 4.4 (p 22-

23) The table shows the important dimensions which were observed, measured and the comparisons between the recommendations in literature and measurement results

3.2 Observations

3.2.1 Floor

The situations of the floor level in the five kitchens are shown in Table 3.2

No 1

Two thresholds (12cm high) between the kitchen and bathroom

A simple ramp was made Very inconvenient

No 2 No any curbs/ thresholds Easy to access the door

No 3 No any curbs/ thresholds Easy to access the door

No 4 Kitchen floor is lower than

that of other rooms

The floor had been raised

A ramp was built Good

Table 3 2: Floor level changes in the five kitchens

Change of the floor level may cause inconvenience or inaccessibility for wheelchair users Therefore, steps and thresholds inside a flat should be avoided as much as possible

If a step or threshold must be set in a flat, the height of the steps and thresholds should be low

so that a wheelchair can easily get across them According to the NKBA Guidelines (Peterson,

1998, p12), “The threshold should not be higher than ½” (1.27cm) (beveled) or ¼” (0.64cm)

(Square).” According to the Singapore Guidelines (Building and Construction Authority,

2002), “Kerbs for roll-in shower stall shall not be more than 10 mm high, beveled at a slope of

1:2.” The Singapore Guidelines also recommends that any changes in level shall conform to

Table 3.3 A step or threshold should be designed following these guidelines

Changes in Vertical Rise, (mm) Gradient not Steeper than

3.2.2 Countertop

The countertop height of each kitchen was measured and the owner’s comment was also recorded The results are listed in Table 3.4

Kitchen Countertop height Knee space Owner’s comment

No 1 84cm Not available A little high

No 2 88cm Not available Too high

No 3 89cm Not available Too high

No 4 75cm Not available Suitable

No 5 85cm Not available Suitable

Table 3 4: Heights of the countertops in the five kitchens

There were mainly two problems about the countertop: one was the unsuitable height, the other was the lack of knee space Working at a countertop which was too high, a wheelchair user had several difficulties: (1) he/she could not see inside the pot on the cooker; (2) he/she could not reach the bottom of the sink; (3) he/she had to raise his/her arm very high when stirring ingredients in the pot, washing ingredients in the sink or cutting ingredients on the countertop; (4) without the knee space, a wheelchair user had to sit at the countertop laterally; he/she had

to turn his/her body facing the sink or cooker and so it was very uncomfortable

3.2.3 Wall Cabinet and Corner Cabinet

Table 3.5 shows the heights of the bottoms of the wall cabinets in the five kitchens Except for Kitchen No 1, all the wall cabinets were unreachable by the owners

Kitchen Height of the wall

Table 3 5: Heights of the bottoms of the wall cabinets

For the lowest drawers of the base cabinet and the corner cabinet, all the wheelchair users had great difficulty in reaching the objects

3.2.4 Ventilation Hoods, Sockets and Switches

In the two modified kitchens, the ventilation hoods were lowered so that the users could reach them The heights of the ventilation hoods in the five kitchens are listed in Table 3.6

Kitchen Height of the

Table 3 6: Heights of the ventilation hoods

The sockets and switches on the wall behind the countertop were very difficult to reach by all the wheelchair users They were often highly installed, and because of the countertop beneath them, a wheelchair user could not get close to them As a result, they became impossible to reach

3.2.5 Washing Machine and Clothes Drying

In the five houses, all the washing machines were placed in the kitchen In fact, it is common for laundry to be done in the kitchen in HDB flats However, because all the washing machines were top-loaded, the openings were too high for the wheelchair users to take the washed clothes out of the washing machines Therefore, the wheelchair users did not use them

Most Singapore residents in HDB flats use bamboo poles to hang wet clothes out through the window for drying However, it was impossible for the 5 wheelchair users to do so The clothes hanging devices inside the kitchens were also too high for the wheelchair users to reach

3.3 Floor Plan of the Five Kitchens

All the five kitchen floor plans were mapped and the main dimensions were measured Figure 3.1 is the floor plan of Kitchen No 1 The area between the countertops was enough for a wheelchair to turn The countertop was L-shaped but the leg of the “L” for placing sink was not long enough The place of the refrigerator was not easy for a wheelchair user to access

because the refrigerator door could not be fully opened As for Kitchen No 2, the owner commented that she felt troubled to move her wheelchair round the washing machine when entering the kitchen from the living room (Figure 3.2) In Kitchen No 3, the refrigerator was not very accessible because it was placed at the corner and the door could not be fully opened (Figure 3.3)

Figure 3 1: Floor layout plan of Kitchen No 1 (unit: m) (R- refrigerator)

Figure 3 2: (Left) floor layout plans of Kitchens No 2 (unit: m) (R- refrigerator;

WM- washing machine)

Figure 3 3: (Right) floor layout plans of Kitchens No 3 (unit: m) (R- refrigerator;

WM- washing machine; T- table)

Figures 3.4 and 3.5 are the floor plans of the two modified kitchens The walls in both kitchens were removed for a more accessible room In Kitchen No 4 (Figure 3.4) the wall between the kitchen and balcony was removed because the kitchen area was constrained Before the modification, the kitchen was 7.53m2 and it was too small for its owner After the modification, the area was 14.9m2 by incorporating the balcony Then the refrigerator and the washing machine could be placed on the balcony The doors between the kitchen and bathroom were also removed to create a wider passage

In Kitchen No 5 (Figure 3.5), the wall between the kitchen and the living room was removed too A wide ramp was built since the kitchen floor is lower than the living room Both the owners were very satisfied with the modification of the walls The findings of the observations were tabulated in Table 5.9 (p 70-72) for a comparison

Figure 3 4: (Left) floor layout plan of Kitchen No 4 (unit: m) (R- refrigerator; WM-

washing machine; T- table)

Figure 3 5: (Right) floor layout plan of Kitchen No 5 (unit: m) (R- refrigerator;

WM- washing machine; T- table)

3.4 Summary

It was found that the barriers observed in the Singapore home kitchens are similar to those found in the literature review related to Western wheelchair users Barriers for wheelchair users in kitchens can be classified into two categories: those related to the vertical design and those related to the design of the floor layout The barriers related to the vertical design exist in: a) the changed floor level; and b) improper height of countertop, cabinet, switches/outlets and appliances The barriers related to the floor plan design exist in: a) improper location and width of door; b) insufficient space for a wheelchair; c) lack of knee space under countertop, sink, cooker, etc.; and d) an improper kitchen countertop layout In the experiment, the above issues were re-addressed, physically tested and verified with findings from the literature

CHAPTER IV VERTICAL DESIGN OF KITCHENS

As discussed in Chapter III, the primary barriers for wheelchair users in a kitchen were classified into two categories: those related to vertical design and those related to floor plan design In this chapter, the vertical design of kitchens is discussed

In a kitchen, the heights of countertop, appliance, cabinet, and switches/outlets are closely linked to the user’s body dimensions and their reach The studies (Floyd, et al., 1966; Jarosz, 1996; Stoudt, 1981; Wright, et al 1997) showed that the anthropometry of people without disabilities simply does not reflect the size, reach, and strength data of persons with disabilities

However, there is lack of information on the anthropometry of the wheelchair users in Singapore Though three anthropometric studies were conducted in 1985, 1988, 1995 (Lim et

al 1986; Ong et al 1988; Singh et al 1995), none of the samples included the wheelchair users Therefore, a pilot study on anthropometric dimensions of wheelchair users in Singapore was conducted

This pilot study examined the approximate reaches of Singapore wheelchair users and their body dimensions As Western data could not be directly applied to the local context and no recommendations on some important reaches and body dimensions were available in the local guidelines, this anthropometric study at least provided more suitable recommendations on the vertical design of the mock-up test kitchens Anthropometry principles were applied to data collection and analyses (for details of the principles please see Appendix 5: Anthropometry Principles)

4.1 Subjects

The study was carried out at the HWA in Singapore All the subjects were the clients of the HWA who attended the physiotherapy and sports training in HWA once or twice a week 16 male and 16 female wheelchair users were measured

In order that the small sample size in this study can be representative of the wheelchair users in Singapore, three criteria for subject selection had to be met: (1) their age distribution should be even; (2) their ethnic distribution should be according to the proportion of the population in Singapore; (3) their health conditions should comprise most of the symptoms The distributions are listed in Table 4.1, 4.2 & 4.3

Number of Subjects Age (years)

Table 4 2: Ethnic distribution of the subjects (* the ethnic proportion is according

to Singapore Department of Statistics (2002))

Number of Subjects Health conditions

Table 4 3: The health conditions of the subjects

4.2 Method for Taking Measurements

Six types of reach for each wheelchair user were measured These measurements were chosen because they were most likely to be used for the barrier-free kitchen design They were: (1) upward reach; (2) up-forward reach to a wall; (3) down-forward reach to a wall; (4) downward reach laterally; (5) forward reach over a table; (6) lateral reach over a table

No detailed method was found on how the anthropometry of wheelchair users determines the kitchen dimensions Only some illustrations show the relationships between the reaches of the wheelchair users and the kitchen dimensions Based on these illustrations, the important reaches were selected for measurement Table 4.4 (p 22-23) shows the original illustrations and the corresponding reaches which were measured

In each type of reach, both comfortable reach and maximum reach were measured The definitions of the comfortable and maximum reach were given by Floyd et al (1966) in their

anthropometric research about the wheelchair user’s reach “A comfortable reach was defined

as one in which the erect sitting posture was maintained, and only the reaching arm was moved Whereas in determining the maximum reach, any body movements were allowed provided that the subjects remained in contact with the seat” (Floyd, et al., 1966, p27)

Since the time available for measuring was limited, (the clients stayed at HWA for only a short time, and they had to attend training activities), the reaches were measured only on their better functional arm

A measuring board was used to indicate the reaching distances The grid unit was centimeter Because when a wheelchair user is cooking, he/she is usually required to grasp cooking tools, bowls and other utensils rather than to touch them, the grasp reaches were measured

When a subject making a reach, he/she held a wooden stick and pointed it against the board Simultaneously, the surveyor observed the position of the stick in order that it was perpendicular to the measuring board Thus the correct distance was read For details about the measurement methods please see Appendix 6: Methods for Measuring the Reaches

Besides the six types of reach, the knee heights as well as the wheelchair armrest heights were collected These two heights were chosen because they are closely related with the countertop height

4.3 Data Statistics

The data obtained from the 16 male and 16 female subjects were statistically analyzed with the program “SPSS” Means, standard deviations, variance, range, 5th, 50th and 95th percentile values were calculated (For details please see Appendices 7, 8, 9 & 10)

A commonly accepted rule is that the designer should try to accommodate at least 90 percent

of his population In order to accommodate 90 percent of a group, the 5th to 95th percentile should be designed for The extreme values represent chance occurrence which should be disregarded in design Removing 5 per cent at both ends of the range will eliminate most of these “freak” values and leave a range covering 90 percent of the population It is applicable when the population is large In a large group, for example, the whole population of the wheelchair users in Singapore, it may be unrealistic and uneconomical to accommodate the spread from least to greatest value encountered in the group

However, for this study on the wheelchair users’ reaches, the selected sample size was small (only 32 persons totally) In order to secure that the estimation would be suitable for more wheelchair users, estimation was made based on the minimum reach of the subjects The measurement results are shown in the Table 4.4

Observations in the 5 kitchens Illustration figure Dimensions recommended in

literature Dimensions measured or calculated Measurement result Applications

Two subjects could reach the ventilation hood (at the

Upward reach (Left: Max; Right: Com.)

Max: 135cm; Com: 128cm

Ventilation hood (applied to the mock-up kitchens which were designed and tested)

(Source: Stratton, 2001)

According to Stratton (2001):

Up-forward reach is 122cm (Fingertip reach)

Down-forward reach is 38cm (Fingertip reach)

The lower part of the cabinet was difficult to reach by all

Down-forward reach is 40cm (Fingertip reach)

Up-forward reach to a wall (Left: Max; Right: Com.)

Down-forward reach to a wall (Left: Max; Right: Com.)

Up-forward reach:

Max: 121cm; Com: 110cm Down-forward reach:

Max: 35cm; Com: 42cm

Handles of doors/drawers, switches/outlets, shelves, etc (applied to the mock-up kitchens which were designed and tested)

The corner cabinet and the lowest drawer were difficult to

reach by all the subjects

(Source: Building and Construction Authority, 2002)

Downward reach laterally is 25cm

Downward reach laterally (Left: Max; Right: Com.) Max: 32cm; Com: 41cm

Handles of the lowest drawers (applied to the mock-up kitchens which were designed and tested)

Observations in the 5 kitchens Illustration figure Dimensions recommended in

literature Dimensions measured or calculated Measurement result Applications

Because in the five kitchens no knee space was provided

under the counter, such kind of reach was not observed

(Source: Building and Construction Authority, 2002)

Forward reach is the 50cm

Forward reach over a table (Left: Max; Right: Com.)

(The table is at height of 86cm) Max: 50cm; Com: 43cm

The cooking tools on the wall behind the countertop were

hard to reach by all the subjects The depth of the

(The table is at height of 86cm) Max: 50cm; Com: 41cm

A free-standing countertop shelf unit can be used (Source: Barrier Free Environments, Inc., 1991)

The wall cabinets were difficult by all the subjects (at the

heights more than 134cm)

Wall cabinet Not available

The height of the wall cabinet bottom was calculated based

on the maximum and comfortable reach over a table

Max: 116cm; Com: 106cm

Wall cabinets (applied to the mock-up kitchens which were designed and tested)

Two subjects felt the countertop too high (at the height of

88cm and 89cm)

Two subjects felt suitable (at the height of 75cm & 85cm)

One subjects felt a little high (at the height of 85cm)

Countertop height (Peterson, 1998)

The countertop height should

be decided by the wheelchair user’s knee height, the thickness of the sink or cooker

as well as the wheelchair armrest height

Knee height and wheelchair armrest height were measured

When a wheelchair user sits in a “desk arm” or “sport model” wheelchair, the countertop height can be estimated as his/her knee height plus a clearance between the knee and the counter’s bottom and 15cm for the counter’s thickness

When the wheelchair user sits in a “standard arm”

wheelchair, the countertop height should be the armrest height plus a clearance between the armrest and the counter’s bottom and 15cm for the counter’s thickness

Based on the knee height range, the countertop height should be largely from 70cm to 85cm Based on the armrest height range, the countertop height should be largely from 75cm

to 90cm

Countertop height (three heights, 75cm, 80cm and 85cm, were applied to the mock-up kitchens which were designed and tested)

Table 4 4: Comparison between the observations, illustrations, measurement results and their applications (Max- Maximum reach; Com- Comfortable reach)

4.4 Measurement Results and Discussion

The top part of a common refrigerator is often a freezer According to the Barrier Free Environments, Inc (1991), 50% of the freezer volume should be within reach of a wheelchair user (Figure 4.18) On the basis of the measurement results, if the freezer is seldom used by a wheelchair user, the middle height of the freezer could be about 135cm If the freezer is frequently used by the wheelchair user, then the middle height of the freezer should be about 128cm because most of the wheelchair users can reach such height comfortably

Figure 4 1: Freezer in the wheelchair user’s reach (Source: Barrier Free

Environments, Inc., 1991)