Anti-heat stress clothing for construction workers in hot and humid weather Report 25 23 July 2013

Content 1. Criteria for sourcing fabrics 2. Reliability of data obtained from the fabric tests 3. Reasons of the different fabrics between shirts and trousers 4. Progress report Radar chart Initial design of clothes and trousers

1. Criteria for sourcing fabrics 1) To identify the requirements of clothing worn by construction workers during summer. Aesthetic (Visual and hand comfort) Fabric hand test Colour Mechanical function UV protection IR (radiation heat protection) Abrasion resistance Elastic test Antibacterial and deodorant function Weight and thickness Anti-heat stress Air permeability Water vapour permeability Moisture management treatment

2) Modeling (Tool: Computer simulation) Shortcomings: Interaction among the properties makes it complex. Method: Fix the other properties, the heat and moisture property (output of computer simulation) will not changed a lot when the specific property varies in a range. 1st step. Ranges of core properties 3rd step. Ranges of aesthetic properties 2nd step. Ranges of mechanical properties An interactive range will be found out.

2. Reliability of data All experimental preparation, steps, operation methods, and tools base on ATSM standards. Prepare the fabrics: Standard washing all fabrics (including standard wash detergent -AATCC Detergent Without Optical Brightener, and standard wash method). Then put all fabrics inside a thermostatic chamber (20°C and 65 RH) for 24 hours. Prepare the samples: ensure the test samples to be used are homogeneous. Testing apparatus are manufactured according to ATSM standards. Calibration of testing apparatus– Generally, it was done by the supplier. 4. All tests are conducted in an environment of 21oC and 65 %RH. Test steps are according to ATSM standards.

3. Fabric of shirt and trousers Generally, the same fabric can be used for constructing both shirts and trousers. However, according to differential requirements of shirts and trousers for workers, different fabrics are required. 1) For T-shirt: According to the distribution of sweat glands and the regulation of venous return, the upper body requires better air permeability and water vapour permeability. Moreover, in consideration of construction workers’ movement when they undertake physical work, good elasticity is also important. Knitted fabrics are always used to construct T-shirt for its good heat and moisture properties, comfort, lightweight [Mavruz & Ogulata, 2010], and ease to move.

2) For trousers: In consideration of safety of construction workers, abrasion resistance of trousers is very important. Woven fabrics are always used to construct trousers for its good abrasion resistance, stiffness and drapability.

Radar chart Method: 1. Scales from 1 to 5, 1 represents ‘worst’, 5 represents ‘best’. Based on the standards for Anti-static, Contact angle, MMT, and Water vapor transfer rate. Based on the mean values and standard deviation of data if no standards are available. 2. Setting weight for each property. 3. Calculation of area by the weighted average.

T-shirt

It is assumed that the weight of each property is 1.

It is assumed that each property has different weight.  Anti-heat stress properties: weight=0.5  Mechanical properties: weight=0.3  Aesthetic properties: weight=0.2 Anti-heat stress properties Mechanical properties Aesthetic properties Air permeability Thickness Anti-static Thermal conductivity Weight MMT UPF rating Water vapour permeability Contact angle Abrasion resistance

Composite scores Criteria Weight K2990 #46 blue (Kitting, 100%cotton) K1710 #B5 khaki (Kitting, 60%C 34%P 6%S) K3159 #B3 khaki (Kitting, 95%C 5%S) K3431 #2 yellow (Kitting, 95%C 5%S) K3559 #26 yellow (Kitting, 95%C 5%S) Nano-tex (Green) Nano-tex (Blue) Nano-tex (White) Coolmax 100% (White) Coolmax 100% (Red) Coolmax89%+Spandex11% (150g/cm2) Coolmax89%+Spandex11% (Gray)(169g/m2) CIC T shirt Thickness (mm) 0.3 5 3 4 2 1 Weight (g/100cm2) Air resistance (KPa·s/m) 0.5 Thermal conductivity (W/m°C) Anti-static (*10^11 ohms) 0.2 Contact angle °(Front) Invalid Contact angle °(Back) Overall Moisture Management Capacity (OMMC) Abarison-15000-Weight loss percentage (%) Water vapor transfer rate (g/day/m2) UPF rating When weight=1 Composite Score 41 42 33 31 43 26 32 30 39 35 37 Different weights 15 15.1 12.2 11.2 15.6 11.6 9.1 12.1 10.3 13.2 14.3 12.4

Trousers

It is assumed that the weight of each property is 1.

Composite scores Criteria Weight gray, Woven, Twill, 100%C blue, Woven, Twill, 98% Cotton, 2% Spandex J-1061 #6 gray, Woven, 95%cotton 5%spandex J-2081 #16 blue, Woven, 100%cotton A-4484 #26 gray, Woven, Canvas, 100%cotton A-5525 #15 blue, Woven, Canvas, 100%cotton Denim, C358fB-C1 #37 Denim, T172AN #37 Denim, C193FYS Denim, 6765 #37 Denim, X042-212 HN1 (60%Cotton,40%polyester) HN2 (40% Cotton, 60% Polyester) HN3 (60%Cotton,40%polyester) Cotton 57%+Coolmax18.5% Bamboo fiber 40% + Coolmax 40% Nylon FSD CIC Thickness (mm) 0.3 4 3 1 5 Weight (g/100cm2) 2 Air resistance (KPa·s/m) 0.5 Thermal conductivity (W/m°C) Anti-static (*10^11 ohms) 0.2 Contact angle '(Front) Contact angle '(Back) Overall Moisture Management Capacity (OMMC) Abarison-15000-Weight loss percentage (%) Water vapor transfer rate (g/day/m2) Null UPF rating When weight=1 Composite Score 32 35 43 42 31 34 38 44 45 26 46 33 Different weights 11.7 11.1 12.6 15.2 14.7 10.8 12.8 12.3 14.3 13 11.2 15.7 16.6 15.1 8.1 14.1 16.7 12.4 However, it might not be judged them only by the weight average. Computer simulation should be conducted to judge whether the fabric is good or not.