To function as source control, a fabric mask must be able to filter micro-droplets (≥5 µm) in exp... more To function as source control, a fabric mask must be able to filter micro-droplets (≥5 µm) in expiratory secretions and still allow the wearer to breathe normally. This study investigated the effects of fabric structural properties on the filtration efficiency (FE) and air permeability (AP) of a range of textile fabrics, using a new method to measure the filtration of particles in the described conditions. The FE improved significantly when the number of layers increased. The FE of the woven fabrics was generally higher, but double-layer weft knitted fabrics, especially when combined with a third (filter) layer, provided a comparable FE without compromising on breathability. This also confirmed the potential of nonwoven fabrics as filter layers in masks. None of the physical fabric properties studied affected FE significantly more than the others. The variance in results achieved within the sample groups show that the overall performance properties of each textile fabric are a produ...
The purpose of fabric masks in the prevention of the spread of COVID-19 often requires that the m... more The purpose of fabric masks in the prevention of the spread of COVID-19 often requires that the masks be worn for extended periods without removal. The management of the conditions in the micro-climate inside the masks is important to keep the wearer comfortable and enhance user compliance. In this study, the effect of mask design and fabric type on the micro-climate was investigated using thermocron iButtons to record the temperature and humidity inside the masks. It was found that the mask style, and its effect on the amount of air incorporated in the micro-climate, had a significant influence on the factors that determine the temperature and humidity levels. In the shaped masks, the impact of the mask design on the results was stronger than the effect of fabric type. In the folded masks that fit snugly around the face, the effect of fabric type was significant, and both fibre composition and fabric structure contributed to the differences in the performance of the three fabrics t...
Opsomming vi LIST OF FIGURES PAGE 1.4. Hypothesis To evaluate disinfection properties: The Anol... more Opsomming vi LIST OF FIGURES PAGE 1.4. Hypothesis To evaluate disinfection properties: The Anolyte, filtered water, detergent, and sodium hypochlorite solution will reduce/inhibit the growth of E. coli and Staph. aureus. Different temperatures of 24, 30 and 60°C will influence the efficacy of the Anolyte, filtered water, detergent, and sodium hypochlorite solution. To evaluate the influence on fabric properties: The Anolyte, filtered water, detergent, and sodium hypochlorite solution will have an effect on the tensile strength of the polyester, polyester/cotton and cotton. Different temperatures of 24, 30 and 60°C will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tensile strength of the polyester, polyester/cotton and cotton. The number of laundering cycles (5, 10, and 20) will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tensile strength of the polyester, polyester/cotton and cotton. The Anolyte, filtered water, detergent, and sodium hypochlorite solution will have an effect on the tearing strength of the polyester, polyester/cotton and cotton. Different temperatures of 24, 30 and 60°C will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tearing strength of the polyester, polyester/cotton and cotton. The number of laundering cycles (5, 10, and 20) will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tearing strength of the polyester, polyester/cotton and cotton. 1.5. Terminology Detergents: Organic molecules that serve as wetting agents and emulsifiers because they have both polar hydrophilic and nonpolar hydrophobic ends. Due to their amphipatic nature, detergents solubilize otherwise insoluble residues and are very effective cleaning agents (Prescott, Harley & Klein, 2005). Dimensional stability: A general property of a material, component or structure, which enables it to maintain or retain its shape, size or any dimension (Wolff, 2004). Disinfection: The killing, inhibition or removal of microorganisms that may cause disease. The primary goal is to destroy potential pathogens, but disinfection also substantially reduces the microbial population (Prescott, Harley & Klein, 2005). Electrochemical Activation: A technology used to produce meta-stable aqueous media by way of electrochemical exposure (Bakhir et al., 2006). Elongation: The limiting tensile deformation that corresponds to tensile strength and is expressed in percent of the test length (Švédová, 1990). Inoculum; Inoculation: Implantation of microorganisms into a culture medium to encourage their growth; a culture medium containing microorganisms (Thiry, 2010b) Log reduction: A reduction of bacteria on a (base 10) logarithmic scale (Thiry, 2010b). Sterilization: The process by which all living cells, viable spores, viruses and viriods are either destroyed or removed from an object or habitat (Prescott, Harley & Klein, 2005). Tearing strength: The force required to propagate an existing tear (Saville, 2004).
Tydskrif vir Gesinsekologie en Verbruikerswetenskappe, 2012
Silk is a luxurious fibre with a unique combination of properties. However, this and other factor... more Silk is a luxurious fibre with a unique combination of properties. However, this and other factors such as the costly production process make silk a very expensive fabric and therefore unaffordable for many consumers. Mixed fabrics might provide a solution to this problem of relative cost if the G onometa postica silk could be mixed with an appropriate fibre. Therefore, mixed yarn fabrics were constructed to evaluate and compare the physical properties of the Gonometa postica silk fabric with those of the mixed fabric consisting of Gonometa postica silk weft on a wool warp. The properties were evaluated in terms of tensile strength (ISO 13934), stiffness (British Test Method 3356), crease recovery (AATCC Test Method 66), and shrinkage (AATCC Test Method 99). Results indicated that the silk weft on wool warp fabric had good crease recovery and the stiffness had a close relation to that of the silk fabric, as well as adequate tenacity. This leads to the conclusion that wool would be c...
Barriers experienced by people with disabilities participating in income-generating activities. A... more Barriers experienced by people with disabilities participating in income-generating activities. A case of a sheltered workshop in Bloemfontein, South Africa', African Journal of Disability 9(0), a662.
Purpose The South African wool industry is integral to the country's agricultural sector, par... more Purpose The South African wool industry is integral to the country's agricultural sector, particularly sheep farming and wool production. Small-scale farmers play a vital role in this industry and contribute to employment and food security in rural communities. However, these farmers face numerous challenges, including a lack of funding, poor farming practices and difficulty selling their wool at fair prices. This study aims to address these challenges, the University of Free State launched a wool value chain project for small-scale farmers. Design/methodology/approach In this project, one of the studies conducted assessed the effectiveness of different detergents suitable for traditional wool scouring methods for small-scale farmers who lack access to sophisticated machinery. The investigation was conducted by scouring 160 wool samples using three different detergents and filtered water as a control. The wool samples were then evaluated for their cleanliness, brightness and fib...
Textile materials are usually sterilised with chemicals like sodium hypochlorite, and temperature... more Textile materials are usually sterilised with chemicals like sodium hypochlorite, and temperatures up to boiling point. Chemical treatment poses two potential problems: firstly, a negative effect on strength properties of the textile fabric, and secondly, the fact that harmful chemicals are discarded into the environment. Electro-chemically activated water (ECA) is produced by an anode-cathode system, with water and diluted NaCl being the only raw products used. After production the Anolyte exists in a metastable state, containing free radicals and a variety of molecules and very high oxidation-reduction potential. However, the Anolyte returns to a stable state after 48 hours and therefore it is not a threat to the environment when discarded after use. Cotton, polyester and polyester/cotton swatches were inoculated respectively with Escherichia coli and Staphylococus aureus . The swatches were laundered using AATCC Test Method 61-2009 at temperatures of 24 °C, 30 °C and 60 °C. Dilut...
To function as source control, a fabric mask must be able to filter micro-droplets (≥5 µm) in exp... more To function as source control, a fabric mask must be able to filter micro-droplets (≥5 µm) in expiratory secretions and still allow the wearer to breathe normally. This study investigated the effects of fabric structural properties on the filtration efficiency (FE) and air permeability (AP) of a range of textile fabrics, using a new method to measure the filtration of particles in the described conditions. The FE improved significantly when the number of layers increased. The FE of the woven fabrics was generally higher, but double-layer weft knitted fabrics, especially when combined with a third (filter) layer, provided a comparable FE without compromising on breathability. This also confirmed the potential of nonwoven fabrics as filter layers in masks. None of the physical fabric properties studied affected FE significantly more than the others. The variance in results achieved within the sample groups show that the overall performance properties of each textile fabric are a produ...
The purpose of fabric masks in the prevention of the spread of COVID-19 often requires that the m... more The purpose of fabric masks in the prevention of the spread of COVID-19 often requires that the masks be worn for extended periods without removal. The management of the conditions in the micro-climate inside the masks is important to keep the wearer comfortable and enhance user compliance. In this study, the effect of mask design and fabric type on the micro-climate was investigated using thermocron iButtons to record the temperature and humidity inside the masks. It was found that the mask style, and its effect on the amount of air incorporated in the micro-climate, had a significant influence on the factors that determine the temperature and humidity levels. In the shaped masks, the impact of the mask design on the results was stronger than the effect of fabric type. In the folded masks that fit snugly around the face, the effect of fabric type was significant, and both fibre composition and fabric structure contributed to the differences in the performance of the three fabrics t...
Opsomming vi LIST OF FIGURES PAGE 1.4. Hypothesis To evaluate disinfection properties: The Anol... more Opsomming vi LIST OF FIGURES PAGE 1.4. Hypothesis To evaluate disinfection properties: The Anolyte, filtered water, detergent, and sodium hypochlorite solution will reduce/inhibit the growth of E. coli and Staph. aureus. Different temperatures of 24, 30 and 60°C will influence the efficacy of the Anolyte, filtered water, detergent, and sodium hypochlorite solution. To evaluate the influence on fabric properties: The Anolyte, filtered water, detergent, and sodium hypochlorite solution will have an effect on the tensile strength of the polyester, polyester/cotton and cotton. Different temperatures of 24, 30 and 60°C will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tensile strength of the polyester, polyester/cotton and cotton. The number of laundering cycles (5, 10, and 20) will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tensile strength of the polyester, polyester/cotton and cotton. The Anolyte, filtered water, detergent, and sodium hypochlorite solution will have an effect on the tearing strength of the polyester, polyester/cotton and cotton. Different temperatures of 24, 30 and 60°C will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tearing strength of the polyester, polyester/cotton and cotton. The number of laundering cycles (5, 10, and 20) will affect the influence of Anolyte, filtered water, detergent, and sodium hypochlorite solution on the tearing strength of the polyester, polyester/cotton and cotton. 1.5. Terminology Detergents: Organic molecules that serve as wetting agents and emulsifiers because they have both polar hydrophilic and nonpolar hydrophobic ends. Due to their amphipatic nature, detergents solubilize otherwise insoluble residues and are very effective cleaning agents (Prescott, Harley & Klein, 2005). Dimensional stability: A general property of a material, component or structure, which enables it to maintain or retain its shape, size or any dimension (Wolff, 2004). Disinfection: The killing, inhibition or removal of microorganisms that may cause disease. The primary goal is to destroy potential pathogens, but disinfection also substantially reduces the microbial population (Prescott, Harley & Klein, 2005). Electrochemical Activation: A technology used to produce meta-stable aqueous media by way of electrochemical exposure (Bakhir et al., 2006). Elongation: The limiting tensile deformation that corresponds to tensile strength and is expressed in percent of the test length (Švédová, 1990). Inoculum; Inoculation: Implantation of microorganisms into a culture medium to encourage their growth; a culture medium containing microorganisms (Thiry, 2010b) Log reduction: A reduction of bacteria on a (base 10) logarithmic scale (Thiry, 2010b). Sterilization: The process by which all living cells, viable spores, viruses and viriods are either destroyed or removed from an object or habitat (Prescott, Harley & Klein, 2005). Tearing strength: The force required to propagate an existing tear (Saville, 2004).
Tydskrif vir Gesinsekologie en Verbruikerswetenskappe, 2012
Silk is a luxurious fibre with a unique combination of properties. However, this and other factor... more Silk is a luxurious fibre with a unique combination of properties. However, this and other factors such as the costly production process make silk a very expensive fabric and therefore unaffordable for many consumers. Mixed fabrics might provide a solution to this problem of relative cost if the G onometa postica silk could be mixed with an appropriate fibre. Therefore, mixed yarn fabrics were constructed to evaluate and compare the physical properties of the Gonometa postica silk fabric with those of the mixed fabric consisting of Gonometa postica silk weft on a wool warp. The properties were evaluated in terms of tensile strength (ISO 13934), stiffness (British Test Method 3356), crease recovery (AATCC Test Method 66), and shrinkage (AATCC Test Method 99). Results indicated that the silk weft on wool warp fabric had good crease recovery and the stiffness had a close relation to that of the silk fabric, as well as adequate tenacity. This leads to the conclusion that wool would be c...
Barriers experienced by people with disabilities participating in income-generating activities. A... more Barriers experienced by people with disabilities participating in income-generating activities. A case of a sheltered workshop in Bloemfontein, South Africa', African Journal of Disability 9(0), a662.
Purpose The South African wool industry is integral to the country's agricultural sector, par... more Purpose The South African wool industry is integral to the country's agricultural sector, particularly sheep farming and wool production. Small-scale farmers play a vital role in this industry and contribute to employment and food security in rural communities. However, these farmers face numerous challenges, including a lack of funding, poor farming practices and difficulty selling their wool at fair prices. This study aims to address these challenges, the University of Free State launched a wool value chain project for small-scale farmers. Design/methodology/approach In this project, one of the studies conducted assessed the effectiveness of different detergents suitable for traditional wool scouring methods for small-scale farmers who lack access to sophisticated machinery. The investigation was conducted by scouring 160 wool samples using three different detergents and filtered water as a control. The wool samples were then evaluated for their cleanliness, brightness and fib...
Textile materials are usually sterilised with chemicals like sodium hypochlorite, and temperature... more Textile materials are usually sterilised with chemicals like sodium hypochlorite, and temperatures up to boiling point. Chemical treatment poses two potential problems: firstly, a negative effect on strength properties of the textile fabric, and secondly, the fact that harmful chemicals are discarded into the environment. Electro-chemically activated water (ECA) is produced by an anode-cathode system, with water and diluted NaCl being the only raw products used. After production the Anolyte exists in a metastable state, containing free radicals and a variety of molecules and very high oxidation-reduction potential. However, the Anolyte returns to a stable state after 48 hours and therefore it is not a threat to the environment when discarded after use. Cotton, polyester and polyester/cotton swatches were inoculated respectively with Escherichia coli and Staphylococus aureus . The swatches were laundered using AATCC Test Method 61-2009 at temperatures of 24 °C, 30 °C and 60 °C. Dilut...
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