1. Report 22
Anti heat stress clothing for construction workers in hot and humid weather
27 May, 2013

2. Aim and Objectives of the research
Part one
Aim and Objectives of the research
Aim of the research
The aim of the study is to assess the effects of heat stress on construction workers and to design clothing which is suitable for work in hot and humid weather.   
Objectives
Examine the current dress patterns of construction workers in hot and humid weather;_Jackie, previous study, video, photo, papers, report
Identify the shortcomings of these current dress patterns in dealing with hot and humid weather; _Jackie, previous study, video, photo, papers, report
Determine the physiological conditions of construction workers when subject to different degrees of heat and humidity exposure; _Jackie, team members, previous study, video, photo, papers, report, cooling vest field study results and report
Design and engineer clothing for construction workers which is appropriate for extreme physiological conditions;
Evaluate the effectiveness of the newly designed clothing for construction workers.
To be done

3. Part two
Main work tasks
Design and engineer clothing for construction workers which is appropriate for extreme physiological conditions;
Evaluate the effectiveness of the newly designed clothing for construction workers.

4. Anti heat stress clothing development and evaluation
Phase 1: field survey on construction workers’ requirement for clothing _Done --- to be reported by Jackie
Phase 2: Fabric and garment objective measurement_ be in progress
Phase 3_1: computer simulation for screening new fabrics _Guo YP ---waiting for fabric testing results
Phase 3_2: Design, pattern and production of new clothing _ Han Xiao --- to be started
Phase 4: Evaluate the effectiveness of existing clothing and newly designed clothing for construction workers
Phase 5: Design evaluation field wear trials

5. Phase 1: Field survey on construction workers’ requirement for clothing

6. Phase 2: Fabric and garment objective measurement
Collecting existing clothing and recruited new fabrics according to the requirement
Testing items：
Fiber content;_Song
Thickness_ Jackie
Weight per unit area_ Jackie
Thermal conductivity _ Jackie
Air resistance_ Jackie
Water vapour permeability _Song
Moisture management capacity _Guo
UV-Blocking _Song
IR Radiation _Song
Anti-static properties_ Jackie
Hand properties _Guo
Contact angle_ Jackie

7. Objective Measurement
Basic characters
Protection
Weight per unit area
Thickness_ Thin
UV protection factor (UPF)
IR Radiation
Thermal function
Anti-static properties
耐磨性质测试
Water vapour permeability(↑ )_Vapour permeable(↑ )
Air resistance(↓ )_Breathability(↑)
Thermal resistance(↓ ) _ heat dissipation (↑ )
Handle properties
Thermal insulation (CLO)
Stiffness
Overall moisture management capacity (OMMC) (↑ )_ sweating transfer function(↑ )
Fullness and softness
Smoothness

8. Phase 3_1: computer simulation for screening new fabrics

9. Simulation results

10. Phase 3_2: Design, pattern and production of new clothing

11. Long sleeved T- shirt and long trousers
Possible style
Short sleeved T- shirt and long trousers
To be decided

12. Phase 4: Evaluate the effectiveness of existing clothing and newly designed clothing for construction workers
Lab study
Heat stress
Physiological stress
Psychophysical evaluation

13. Phase 5: Design evaluation field wear trials
Clothing: Newly designed clothing 1 type and existing clothing
Experimental location: selected construction workplaces
Protocol: follow daily routine activities with filling questionnaires and feedback comments after wearing each time.

14. Part three
Review of the project

15. 1. Existing construction uniform in the whole world

16. Existing uniform 1: Long sleeved shirt and trousers

17. Existing clothing 2: Short sleeved T- shirt and long trousers

18. Existing clothing 3: Cooled garments

19. 2. Existing construction uniform in the Hong Kong

20. 2.1 地盤工制服 千瘡百孔搞成年
Existing uniform
成本: 長袖及短袖T 恤每件成本為五十七元及五十二元

21. Existing uniform Long sleeved T-shirt 短袖T 恤制服  反領T 恤以棉質為主， 衣領以橙色和藍色分

22. 風褸制服

23. 2.2

24. 成本: 長袖及短袖T 恤每件成本為五十七元及五十二元

26. 2.3 Construction workers

27. 3. Guidelines/Publication on clothing requirement for construction workers

28. Assessment of Risks for heat stress (C IC, 2008, Guidelines on Site Safety Measures for Working in Hot Weather)
The following factors are particularly relevant to risk assessment for heat stress –
(a) high temperature resulting from work in hot weather, or heat generated by plant and machinery;
(b) exposure to direct sunlight;
(c) high humidity resulting from humid weather or plant or processes generating moisture;
(d) insufficient ventilation in enclosed areas;
(e) heavy physical work; and
(f) wearing of protective clothing which affect heat dissipation from the body.

29. Mitigation of risks
(a) elimination of risks - for example by re-scheduling the construction works, using mechanical aid to replace manual work and providing adequate ventilation for enclosed environment;
(b) reduction of risks – for example by using equipment that generates less heat to reduce the temperature of the works area;
(c) administrative controls and safe work practices – for example by providing appropriate training and work instructions; and
(d) personal protective equipment – for example provision of light clothing or face shields.

30. Risk Assessment for the Prevention of Heat Stroke at Work (http://www
Risk factor Examples of specific control measures for risk factor

31. Risk factor Examples of specific control measures for risk factor

33. Work clothing
Protective clothing can be water-cooled garments, air-cooled garments, ice-packet vests, wetted over garments, heat reflective aprons etc.
Work clothing should not be any more than a long sleeved shirt and trousers (NIOSH, 1986) .

34. Clothing and protective equipment (Construction Industry Council (2008), Guidelines on Site Safety Measures for Working in Hot Weather, Publication No. 2. Version 1, available at: Publications/Working_in_hot_weather.pdf)
(a) encourage workers to keep their shirt or other top on and to wear clothing that is –
(i) light-coloured (to minimize heat absorption and enhance heat dissipation);
(ii) loose-fitting (to enhance perspiration. However, clothing that is too loose
are not suitable because of the risk of entangling in the moving parts of
machines);
(iii) made of natural materials (to enhance heat dissipation); and
(iv) long-sleeved (to minimize exposure of the skin to sunlight when working
outdoors);
(b) encourage the use of naturally ventilated helmet to enhance perspiration; and
(c) encourage the use of helmet with broad brim to provide better shade to the face, neck and back.

35. 地盤工制服 千瘡百孔搞成年

38. Clothing requirement from guide/publication and strategy
Full cotton/close to full cotton_fabric choice
Thin_ testing
Light-coloured_fabric choice
Sweating absorbent_ testing
Sweating transfer to environment from skin and clothing microclimate easily_testing
Vapour permeable_ testing
Breathability_ testing
Collarless?_design
Loose-fitting_design

39. 4. Works done
Collecting fabrics for newly designed uniform

40. Fabrics of T-shirt Company Fabrics Composition & Construction G/M2
Price
KEI NGAI CLOTHING COMPANY LIMITED
k17110
kitting
60%Cotton, 6% Spandex，34% polyester
170
HK$ 30.00/Y
k3559
95%Cotton, 5% Spandex
k3159
220
HK$ 43.00/Y
k3431
180
HK$ 40.00/Y
k2990
100%Cotton
140
HK$ 25.00/Y

41. Fabrics of trousers Company Fabrics Composition & Construction Price
YU TEX COMPANY
A-5525
Woven, 100%Cotton
HK$ 35.00/Y
K-4484
JCYO TEXTILE
J-1061
Woven,
95%Cotton, 5% Spandex
HK$ 24.00/Y
J-2081
HK$ 26.00/Y
Bao Rong
Woven, Twill
98%Cotton, 2% Spandex
HK$ 25.00/Y
100%Cotton

42. Retroreflective strip

43. Objective measurement -basic characters (1)
1. Weight (g/100 cm2)
Experimental procedure
i) cut 10 pieces of rounded fabric, each piece is 100 cm2
ii) measure the weight of each piece
Tool: Circular Cutter (Schroder GSM); Electronic scale (Smart Grid, METTLER TOLEDO)

47. Objective measurement -basic characters (2)
2. Thickness (mm)
Experimental procedure
i) select a piece of flat fabric, about 10×10 cm2;
ii) measure the thickness on 10 different places of that piece of fabric
Tool: Thickness apparatus (AMES-SDL).

51. Part four
Progress

52. Field study on the three construction sites during 2012 summer
Jackie
Field study on the three construction sites during 2012 summer
Descriptive statistics
Age
Height (cm)
Weight (kg)
Working experience (years)
Mean±SD
43.3±14.07
168.4±5.84
65.0±11.00
17.1±12.33

58. Air resistance

61. Thermal conductivity

64. Progress of fabric testing
Testing items
Progress
Estimated completion time
Action by
Fiber content
In progress
This Friday
Dr Song
Thickness
Nearly completed
This Wednesday
Jackie
Weight per unit area
Thermal conductivity
Air resistance
Water vapour permeability
Next Wednesday
Moisture management capacity
Dr Guo
Anti-static properties
Not yet start
Next week
Hand properties
Contact angle
Fabric abrasion
Next Thursday

65. Further search on fabric_Song Wen Fang
Manufactory
Component
Weight
Property announced
Price
Dupont (Zhangjiagang Shijiapeng textile company)
Coolmax
100% polyester
(Knit)
140g/m2
Excellent hygroscopic and sweat releasing property, non sticky and excellent anti-static property
HK$25/Y
Dupont (Qingdao Jia Nuo Cheng company)
88%polyester*
12% Spandex
175g/m2
Excellent hygroscopic and sweat releasing and not sticky
HK$43/Y
Far eastern group (Changshu Xundayi company)
Topcool
180g/m2
Excellent hygroscopic and sweat releasing property, UV blocking property, and air permeating property
HK$30/Y
N U of Taiwan
Supercool 100%Polyester with Jade powder inside _
Better hygroscopic and sweat releasing property than coolmax and topcool, higher heat conductivity property and much quicker drying rate that cotton
HK$345/T-shirt

72. Thanks