CTE 4443 Study Guide Exam 2 Comfort Freedom from pain discomfort neutral state pleasant state of physiological psychological and physical harmony between a human being and the environment Psychological comfort implies that individuals need specific garments fabrics colors and design features to help them feel confident and at ease within the context of the various roles they assume Factors Self image Relationship with others Need of privacy Physiological Comfort refers to maintenance of thermal balance The proper relationship between body heat production and loss Factors Cardiovascular system Skeleto muscular system Central nervous system Pulmonary system Digestive system Thermoregulatory mechanism Physical Aspects of Comfort refers to different sensations and feelings of discomfort and or pain which influence the two types of comfort Factors Touch Sight Hearing Taste Smell Physical properties Thermo physiological comfort thermal resistance breathability absorption of water wickability water resistance and drying rate Sensorial Neuro physiological Comfort Prickliness itchiness inflammation Roughness Thermal character warm cool feeling Electrostatic propensity Body Movement Comfort Stretch Weight and Pressure compression Hand tactile touch or sight test for Pliable to stiff Stretchy to non stretchy Springy to limp Smooth to rough Compact to open Cool to warm Harsh to slippery Soft to hard Drape manner in which a fabric hangs over a 3 dimensional form how it bends under its own weight occurs when part of fabric is supported and gravity produces deformation in unsupported portion 0 100 is the drape coefficient above 50 stiff Affects of drapability 1 Fiber content some are more stiff rayon known for drapability 2 Yarn structure tight will have less loose has more 3 Fabric structure high fabric count less drape Moisture Absorbency Ability of material absorbent to take in or absorb another material absorbate Ability to retain liquid water in interstices pores and internal portions Evaluate how quickly liquid absorbed and quantity absorbed at saturation point Specular reflectance shiny reflective surface of water drop when it beads up on surface Water repellency relative resistance of material to surface wetting water penetration or water absorption Water resistance ability of material to withstand penetration by water under pressure or water that drops from distance and strikes against material with known force Waterproof materials resistant to water penetration regardless of pressure or force Water Vapor Transmission Speed with which water vapor passes through material Dessicant method known weight of dried calcium chloride placed in container covered by material weight gain Water method specimen covers pan containing known amount of water water loss by evaporation measured Physical aspects that influence thermal comfort Fabric Mass Fabric Thickness Fiber Yarn and Fabric Structures Porosity is the ratio of air space to the total volume of the fabric expressed as a percentage Cover Factor is defined as the opacity or hiding power in textiles Heat transfer refers to the transfer of heat energy from one environment to another Heat transfer occurs whenever a temperature difference DT exists between two environments heat moves from the warmer surface or area to the cooler surface or area Conduction is the transfer of heat by physical contact either within a body or between two touching bodies Convection is heat transfer via a moving air mass within space Radiation involves heat transfer through space in the form of electromagnetic energy Anti Static Finishes Conditions for static electric charge build up are cool dry environment Manufactured fibers build up static electric charges because they are hydrophobic and do not allow conduction of electrical charges Healthy adult human body can tolerate about 5000 volts 5kV of electrical charges Moisture Transfer It refers to the transfer of liquid water or vapor The transfer of moisture generally is from the wetter environment to the drier environment until equilibrium is reached Moisture is produced by the body in the form of perspiration insensible and sensible perspirations Diffusion Sorption Wicking Evaporation Water Resistance a physical barrier to water penetration Water Repellent does not allow water penetration in one side but it allows moisture transfer from body Waterproof does not allow any penetration of water from either side to the other Hydrophilic absorbs water Hydrophobic repels water Air Permeability It is the degree to which the material is penetrable by air It is also the rate of airflow through a fabric when there is a different air pressure on either surface of the fabric Flammability Combustion A chemical process in which oxidation produces heat energy Flaming combustion Spontaneous combustion Flameless combustion Smoldering By Products of Combustion smoke toxic gas CO most toxic molten polymer compounds melting and dripping Limiting Oxygen Index The amount of oxygen required to support the combustion of a fiber Fibers with LOI above 21 self extinguish Cellulosic 17 20 Wool 25 2 Manufactured 18 2 20 6 Flame resistance the property of a material whereby flaming combustion is prevented terminated or inhibited following application of a source of ignition Fire Triangle In order for there to be a fire three elements must be present Oxygen Fuel and Heat O 2 Fuel Heat Flame retardant finishes work by blocking one leg of the fire triangle usually blocking the oxygen Textiles Fireproof asbestos Noncombustible glass Flame resistant aramid wool modacrylic vinyon saran other high performance fibers Flammable cellulosics natural and manufactured acrylic nylon polyester olefin Flammable Fabrics Act Passed in 1953 Banned the use and sale of highly flammable materials for clothing The standards are published with a Code of Federal Regulation CFR Five new standards have been passed since the original 1967 amendment notation CFR 1630 Large Carpets and Rugs CFR 1631 Small Carpets and Rugs CFR 1632 Mattresses and Mattress Pads CFR 1633 Upholstered Furniture All clothing must meet requirements children s sleepwear specifically regulated by Consumer Product Safety Commission CPSC responsible for recalls on many products boy s pajamas Plain surface textiles passes if 3 5 seconds or more burn time ASTM D1230 Raised fiber textiles flannel passes if 7 seconds or more burn time Some fabrics will self extinguish Mattress testing Under the old