The Effect of Air Gap and Moisture for the Skin Burn Injury of the Firefighter’s Personal Protective Clothing (PPC)

Fire fighters are commonly exposed to intense heat and fire. They suppressed fire by spraying water to avoid flame from spreading. They are enforced to use the Personal Protective Clothing (PPC) made of the flame-retardant material to protect themselves from the skin burn injury. Skin burn injury is the most common injury occurs among them. Yet, the exposure to extreme heat and moisture absorption into the clothing layers caused severe burn injury formation. The purpose of this study is to investigate the effect of air gap combined with the moisture absorption in the fabrics using Finite Element Method (FEM) and the Bio heat Equation. From the simulation experiment it is discovered the air gap is a good insulator capable of preventing skin burn with a skin temperature of 48°C. However, the presence of moisture strongly affects skin temperature. It had elevated to 59.64°C forming a second-degree type burn injury. The presence of moisture had weakened thermal protection of the flame-retardant material and the air gap against the heat flux. It is found the moist material properties had enhanced heat transfer from the heat flux to the skin surface resulting severe skin burn despite they were encapsulated with the Personal Protective Clothing (PPC)

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Steam Burn Injury Model of Firefighter’s Personal Protective Clothing

Science Proceedings Series ◽

10.31580/sps.v1i1.511 ◽

2019 ◽

Vol 1 (1) ◽

pp. 7-11

Author(s):

Zaina Norhallis Zainol ◽

Masine Md Tap ◽

Haslinda Mohamed Kamar

Keyword(s):

Skin Temperature ◽

Protective Clothing ◽

Burn Injury ◽

Thermal Protection ◽

Heat Exposure ◽

Material Condition ◽

Degree Burn ◽

Injury Model ◽

Human Limb ◽

Continuous Heat

Burn injury is one of the most common injury among firefighters. Moisture comes from perspiration or hose spray absorbed in the personal protective clothing and steam burn injury occur with continuous heat exposure. The heat transfer from the heat flux is enhanced due to transformation material properties that holds high thermal conductivity and heat conductivity. Finite element method is used to predict steam burn injury among firefighters. The model is developed in 1dimensional cylinderical quarter geometry representing the human limb. It is discovered the skin temperature 10°C increases with wet material than dry material. The pain threshold at the lower arm of wet material condition is formed 40second rapidly compare to dry material condition. The first degree burn occur at t=9.5second sooner than the dry condition t=25second. The skin temperature increases with the wet material resulting severe skin burn. It is found that the wet personal protective clothing had compromised its thermal protection. Therefore, firefighters will experience high risk of thermal hazard.

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Study on the influence of the thermal protection material on the heat dissipation of the battery pack for energy storage

E3S Web of Conferences ◽

10.1051/e3sconf/202125202045 ◽

2021 ◽

Vol 252 ◽

pp. 02045

Author(s):

Shuping Wang ◽

Fei Gao ◽

Hao Liu ◽

Jiaqing Zhang ◽

Maosong Fan ◽

...

Keyword(s):

Energy Storage ◽

Flame Retardant ◽

Heat Dissipation ◽

Thermal Protection ◽

Storage System ◽

Negative Influence ◽

Thermal Runaway ◽

Air Gap ◽

Battery Pack ◽

Chain Reaction

The thermal runaway chain reaction of batteries is an important cause of the battery energy storage system (BESS) accidents, and safety protection technology is the key technology to protect the BESS. Although the flame retardant thermal protection material can delay the thermal runaway chain reaction between batteries and reduce the heat conduction between batteries, it has a negative influence on the normal heat dissipation of batteries. In this paper, 12 series of batteries were assembled into the battery pack. The battery pack with closely arranged batteries, the battery pack with 3mm air gap between batteries and the battery pack with flame retardant thermal protection material between batteries were studied. The battery temperatures and temperature differences of these three types of battery packs were cyclically charged and discharged at rated power, and the effects of air gap and flame retardant thermal protection materials on the heat dissipation of batteries under charge/discharge cycle were analysed.

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Modeling Exposures of a Nylon-Cotton Fabric to High Radiant Heat Flux

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501601100308 ◽

2016 ◽

Vol 11 (3) ◽

pp. 155892501601100

Author(s):

Thomas Godfrey ◽

Margaret Auerbach ◽

Gary Proulx ◽

Pearl Yip ◽

Michael Grady

Keyword(s):

Heat Flux ◽

Cone Calorimeter ◽

Burn Injury ◽

Thermal Protection ◽

Transient Heat Conduction ◽

Radiant Heat ◽

Heat Fluxes ◽

Direct Result ◽

Face Modeling ◽

Flaming Combustion

American soldiers and marines involved in the recent conflicts in Iraq and Afghanistan have suffered increased incidence of burn injury, often as a direct result of exposure to improvised explosive devices. In this work, a one dimensional numerical pyrolysis model for transient heat conduction, incorporating material transformations described by chemical kinetics, is used to investigate the response of the standard 230 g/m2 Army Combat Uniform (ACU) fabric to high radiant heat fluxes in short duration thermal protection tests and long duration cone calorimeter tests. Thermal protection tests are performed using a Thermal Barrier Test Apparatus–an automated device, incorporating a closed-loop controlled IR radiant heat source, automated water cooled shutter, a fabric sample holder, an adjustable stage with a water cooled Schmidt-Boelter heat flux gauge and a PC based data acquisition system. Cone calorimeter tests are performed on fabric specimens at an exposure heat flux of 25 kW/m2. In thermal protection tests involving exposures of 90 kW/m2 for five seconds and 77 kW/m2 for four seconds, modeling indicated that desorption and evaporation of moisture content has an important effect, but melting of the nylon component and material decomposition had insignificant effects on the heat flux transmitted through the fabric back face. Modeling results for cone testing exhibited good agreement for time to ignition and duration of flaming combustion.

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Investigating the Thermal-Protective Performance of Fire-Retardant Fabrics Considering Garment Aperture Structures Exposed to Flames

Materials ◽

10.3390/ma13163579 ◽

2020 ◽

Vol 13 (16) ◽

pp. 3579

Author(s):

Miao Tian ◽

Qi Wang ◽

Yiting Xiao ◽

Yun Su ◽

Xianghui Zhang ◽

...

Keyword(s):

Boundary Condition ◽

Heat Flux ◽

Thermal Aging ◽

Thermal Protection ◽

Fire Retardant ◽

Air Gap ◽

Protective Function ◽

Thermal Protective Performance ◽

Positive Effects ◽

Protective Performance

The application of fire-retardant fabrics is essential for providing thermal protective function of the garments. Appropriate clothing design are beneficial for preventing the wearers from skin burn injuries and heat strains simultaneously. The intention of this work was to investigate the effects of clothing ventilation designs on its thermal protective performance by bench-scale tests. Four boundary conditions were designed to simulate the garment aperture structures on fabric level. Tests of thermal shrinkage, mass loss and time-to-second-degree-burns were performed with and without air gap under three heat-flux levels for two kinds of inherently fire-retardant fabrics. The impacts of fabric type, heat-flux level, air gap and boundary condition were analyzed. The presence of a 6.4-mm air gap could improve thermal protective performance of the fabrics, however, the garment openings would decrease this positive effects. More severe thermal aging found for spaced test configuration indicated the importance of balancing the service life and thermal protective performance of the clothing. The findings of this study implied that the characteristics of fabric type, air gap, boundary condition, and their effects on fabric thermal aging should be considered during clothing ventilation designs, to balance the thermal protection and comfort of the protective gear.

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On the Effectiveness of Temperature-Responsive Protective Fabric Incorporated With Shape Memory Alloy (SMA) Under Radiant Heat Exposure

Clothing and Textiles Research Journal ◽

10.1177/0887302x19892095 ◽

2019 ◽

Vol 38 (3) ◽

pp. 212-224 ◽

Cited By ~ 2

Author(s):

Lijun Wang ◽

Yehu Lu ◽

Jiazhen He

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Protective Clothing ◽

Thermal Protection ◽

Heat Exposure ◽

Radiant Heat ◽

Air Gap ◽

Environment Change ◽

Temperature Responsive ◽

Thermal Insulating

To improve thermal protection of protective clothing, temperature-responsive protective fabrics incorporated with shape memory alloy (SMA) springs varying on four different deformation heights and five types arrangement modes were designed. The thermal protection was investigated under radiant heat exposure of 0.39 cal/cm2 s. The results indicated that the air gap between fabric layers produced by SMA springs effectively improved protective performance. The thermal protection of fabrics with different SAM arrangement modes and sizes showed different trends, and the interaction effects of arrangement mode and size were analyzed. Moreover, the optimized arrangement and size of SMA springs were suggested. The regression models were established to assess the relationship between the air gap and thermal protection. This study demonstrated that the combination of flame-resistant fabric with SMA was feasible to develop temperature-responsive protective clothing because it could improve thermal insulating property by producing intelligent air gaps that responded to environment change.

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Research on Thermal Protective Performance of Thermal Insulation and Flame-Retardant Protective Clothing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.796.607 ◽

2013 ◽

Vol 796 ◽

pp. 607-612

Author(s):

Fei Fei Li ◽

Chun Qin Zheng ◽

Guan Mei Qin ◽

Xiao Hong Zhou

Keyword(s):

High Temperature ◽

Flame Retardant ◽

Thermal Insulation ◽

Protective Clothing ◽

Thermal Protection ◽

Single Layer ◽

Woven Fabric ◽

Standard Requirement ◽

Thermal Protective Performance ◽

Protective Performance

Thermal insulation and flame-retardant (TIFR) protective clothing, which has good thermal protective performance (TPP), could protect people from high-temperature or flame in casting industry, the petrochemical industry, fire industry and et al. That is, TIFR protective clothing must have certain function of slowing or restraining heat transmission, and insulating radiant heat and convection heat from high temperature heat source. The construction of TIFR protective clothing is being developed from single layer to multi-layer fabrics made by flame-retardant (FR) fibre. In this paper, based on TPP-206 tester, the TPP coefficient of single and multi-layer fabrics with flame-retardant were measured, and the TPP of TIFR protective clothing was analyzed. TPP coefficient of single fabrics included the FR viscose non-woven fabric do not meet the standard. That of all of multi-layer fabrics meet the standard requirement, and the FR viscose/wool blended fabric is not suitable for fire fighter. It is significant and the most observable effect to put the PTFE membrane between the outer layer and the insulating layer. It could improve the overall thermal protection performance.

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The Durability of Flame Retardant and Thermal Protective Cotton Fabrics during Domestic Laundering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.441.255 ◽

2012 ◽

Vol 441 ◽

pp. 255-260 ◽

Cited By ~ 2

Author(s):

Wei Bang Chen ◽

Ying Ying Wan ◽

Fei Que ◽

Xue Mei Ding

Keyword(s):

Thermal Resistance ◽

Flame Retardant ◽

Flame Retardancy ◽

Protective Clothing ◽

Flame Retardants ◽

Thermal Protection ◽

Water Vapor Permeability ◽

Vapor Permeability ◽

Before And After ◽

Resistance Value

Flame retardant fabrics have been broadly used for protective clothing, which have strictly requirements on both flame retardancy and thermal protection. Usually, domestic laundering will be carried out frequently to clean these protective garments. However, little research on the performance durability of this type of fabrics after domestic laundering has been reported. This paper selected fabrics of 8 types of cotton and its blend fibers, which were treated with flame retardants Pyrovatex CP, Proban, CFR-201, SCJ-968 respectively. The damaged length, after flame time, after glow time, TPP value, thermal resistance value, weight, thickness, air permeability and water vapor permeability (WVP) of the samples were measured before and after 15 cycles domestic laundering cycles. Results show that the flame retardancy of the 8 fabrics reduce with launderings as measured by the increase in damaged length and after glow time. The TPP increase probably resulted from the increase in the thickness and thermal resistance of the finished fabrics. Domestic laundering resulted in only a slight change in the comfort properties of the fabrics.

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Effect of Undergarments on Micro-Environment under Anti-Static Dust-Free Clothing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.796.630 ◽

2013 ◽

Vol 796 ◽

pp. 630-633 ◽

Cited By ~ 1

Author(s):

Ying Liu ◽

Han Yu Wu ◽

Yu Ping Li ◽

Xiao Qun Dai

Keyword(s):

Relative Humidity ◽

Skin Temperature ◽

Protective Clothing ◽

Skin Surface ◽

Woven Fabric ◽

Mean Skin Temperature ◽

Climate Chamber ◽

Knitted Fabrics

In this study, the effect of different undergarments on micro-climate environment under anti-static dust-free clothing was investigated. Five male undergraduates participated in wear trials conducted in a climate chamber of 24 ± 1°C and 60 ± 5%RH, three undergarments of different materials were worn under an antistatic dust-free overall respectively. While subjects doing mild exercise, the temperature and relative humidity under the undergarment was measured at chest, and the skin temperature at arm, chest, thigh and calf were measured. It was found that undergarment made of plain woven fabric was the best to keep the relative humidity on skin surface low and mean skin temperature stable during mild exercise among three undergarments of different materials. It was demonstrated that hydrophilic fiber might not the best material of undergarment for protective clothing, knitted fabrics which have more volume to hold water might not be good either. It was showed that materials absorb water and moisture and quick dry is suitable to undergarment for protective clothing.

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