The complex interactions between fabric and garment design, climate, physiological, and psychological variables that define comfort performance make it one of the most important qualities influencing product acceptance by the end user. With capabilities for both objective and subjective measurement techniques, TPACC is the tool that can inform the textile producer whether their efforts have potential for improving comfort while in the research and development stage.
Comfort performance has obvious importance for daily fashion wear, specialized medical applications, varying types of athletic gear, and protective ensembles for military, industrial, and first responder personnel. Protective clothing has a unique and often contradictory set of properties. The essential requirements for protection against the penetration of environmental threats such as toxic chemicals, or hazardous heat exposures, results in a protective garment which itself contributes to the thermal discomfort, or worse, heat illness (exhaustion, hyperthermia, etc.). Employment of TPACC’s integrated and synergistic research and testing approaches may be the only way to define the optimum balance between protection and wearer comfort.
At all stages of the development process TPACC offers unique opportunities to quantify, study, evaluate, and compare the comfort of textile materials – knits , wovens, nonwovens, and composite systems. From fabric swatch to manikin and human subject assessments of garments and ensemble systems, TPACC comfort resources include the following.
Fabric Level Analysis
Kawabata Evaluation System – series of instruments for assessment of the mechanical properties related to fabric hand (compression, bending, surface roughness and friction, shear and tensile).
Qmax Warm / Cool Touch Test – assess the surface warm/ cool sensations of fabrics sensed when there is initial contact of the material with the skin surface.
Guarded Sweating Hot Plate Instrumentation – assessment of heat and moisture transport through the material into a controlled environment; measurements of thermal and evaporative resistance are used to calculate insulation values (clo), permeability, and Total Heat Loss.
- ASTM F 1868 Standard Test Method for Thermal and Evaporative Resistance of Clothing Materials Using a Sweating Hot Plate
- ISO 11092 Textiles – Physiological effects – Measurement of thermal and water-vapour resistance under steady-state conditions (sweating guarded-hotplate test)
Moisture Vapor Transmission Rate – Simple Dish Method, similar to ASTM E96.
- Vertical Wicking – dangling strip test for upward wicking.
- Gravimetric Absorbency Testing System (GATS) – preferred method for measurement of absorption properties. Sometimes called demand wettability, this is a horizontal wicking test that utilizes a porous plate and no driving force.
- Moisture Management Tester – AATCC Test Method 195
- Drying Time – an assessment to determine how fast the material dries from its saturated state.
Subjective evaluation of fabric hand – AATCC Evaluation Procedure 5
Dimensional Changes of Fabrics after Home Laundering – AATCC 135. For many methods, laundry procedures may be a requirement of conditioning.
Garment Ensemble Comfort Evaluations
Sweating Manikin tests – for demonstrating breathability of clothing ensembles
- ASTM F 1291 – Standard Test Method for Measuring the Thermal Insulation of Clothing Using a Heated Manikin
- ASTM F 2370 – Standard Test Method for Measuring the Evaporative Resistance of Clothing Using a Sweating Manikin
- ASTM F 2371 – Standard Test Method for Measuring the Heat Removal Rate of Personal Cooling Systems Using a Sweating Heated Manikin
- ASTM F 1720 – Standard Test Method for Measuring Thermal Insulation of Sleeping Bags Using a Heated Manikin
- ASTM F 2732 – Standard Practice for Determining the Temperature Ratings for Cold Weather Protective Clothing
Sweating Thermal Hand – for evaluating heat and evaporative resistance of gloves
Glove Hand Function Tests – human subject tests of grip and dexterity. ASTM F 2010 Standard Test Method for Evaluation of Glove Effects on Wearer Hand Dexterity Using a Modified Pegboard Test
- NFPA 1971 Grip Test
- Dexterity Lift Test
- Dexterity Tool Test
- Torque Test for Grip
Full Ensemble Comfort – the ultimate garment assessment involving human subjects following a specified protocol that includes periods of exercise alternating with periods of rest in both moderate and mildly warm climatic conditions. This subjective evaluation obtains wear participant opinions via ratings on comfort descriptor terms that have been selected to correspond with fabric level characterizations. Participants sign up for a visit to wear each garment included in the comparison.
Physiological Wear Test – using a specific and limited subject pool, participants are instrumented to collect data on heart rate, skin temperature, and core temperature while following a prescribed protocol. This type of heat stress assessment also gathers data on garment weights and subjective response ratings of key comfort descriptors.
- ASTM F 2300 Standard Test Method for Measuring the Performance of Personal Cooling Systems Using Physiological Testing.
- ASTM F 2668 Standard Practice for Determining the Physiological Responses of the Wearer to Protective Clothing Ensembles
Thermal Imaging – thermographic record of heat loss and retention.