Proposal for a new statistical procedure for the ergonomic design of furniture: implications of a protocol developed from measurements of a young population.

The current approach to the ergonomic design of furniture often relies on a gender-based segmentation, assuming that it yields homogeneous groups. However, this assumption has proved to be inconsistent in various contexts, particularly in regions characterized by ethnic diversity and economic inequalities, leading to diverse anthropometric characteristics. Considering gender alone fails to encompass this heterogeneity. The proposed approach introduces an 'anthropometric segmentation' methodology in which the population is clustered based on a wide range of anthropometric dimensions. Additionally, kernel density estimation is used when normality is not fulfilled. This step is critical, as it informs furniture dimensions by using selected percentiles from these density functions. The proposed approach is applied to a dataset of university students in Peru, a country marked by significant heterogeneity within its male and female populations. Ultimately, our methodology promises to improve the ergonomic design of furniture by accounting for a broader spectrum of anthropometric diversity.

Children's exposure to brominated flame retardants in the home: The TESIE study.

Due to differences in chemical properties and half-lives, best practices for exposure assessment may differ for legacy versus novel brominated flame retardants (BFRs). Our objective was to identify the environment matrix that best predicted biomarkers of children's BFR exposures. Paired samples were collected from children aged 3-6 years and their homes, including dust, a small piece of polyurethane foam from the furniture, and a handwipe and wristband from each child. Biological samples collected included serum, which was analyzed for 11 polybrominated diphenyl ethers (PBDEs), and urine, which was analyzed for tetrabromobenzoic acid (TBBA), a metabolite of 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB). Significant positive correlations were typically observed between BFRs measured in dust, handwipes and wristbands, though wristbands and handwipes tended to be more strongly correlated with one another than with dust. PBDEs, EH-TBB and BEH-TEBP were detected in 30% of the sofa foam samples, suggesting that the foam was treated with PentaBDE or Firemaster® 550/600 (FM 550/600). PBDEs were detected in all serum samples and TBBA was detected in 43% of urine samples. Statistically significant positive correlations were observed between the environmental samples and serum for PBDEs. Urinary TBBA was 6.86 and 6.58 times more likely to be detected among children in the highest tertile of EH-TBB exposure for handwipes and wristbands, respectively (95 % CI: 2.61, 18.06 and 1.43, 30.05 with p < 0.001 and 0.02, respectively). The presence of either PentaBDE or FM 550/600 in furniture was also associated with significantly higher levels of these chemicals in dust, handwipes and serum (for PBDEs) and more frequent detection of TBBA in urine (p = 0.13). Our results suggest that children are exposed to a range of BFRs in the home, some of which likely originate from residential furniture, and that silicone wristbands are a practical tool for evaluating external exposure to both legacy and novel BFRs.

A systematic review of research on sitting and working furniture ergonomic from 2012 to 2022: Analysis of assessment approaches.

This study analyses which aspects of sitting and working furniture ergonomics that may be influenced and how they are assessed. To gather information on the types and assessment techniques connected with influencing furniture ergonomics, a systematic review of the literature was conducted. The papers in the systematic review were published between 2012 and 2022. The articles applied the Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines to limit the 41 papers that were eventually included (N = 41) to those containing keywords like ergonomics, human factors, comfort, working furniture, Chair, assessment and evaluation. The research objective of this systematic review is to provide a comprehensive overview of sitting and working furniture and the main findings, obtaining common assessment techniques for this type of furniture and their suitability. According to the relevant studies, the publications were categorized by summarizing factors like region, gender, research methods, ergonomic assessment techniques and methods used, correlation between assessment techniques and methods, etc. Summaries of the data extracted from the included papers are provided and the applicability of some approaches are assessed. Only a small number of authors have evaluated the ergonomics of furniture used in homes. One of the research gaps is the paucity of research on gender segregation, secular trends, and cultural contexts. These studies heavily rely on quantitative research techniques, and the articles may lack credibility due to the homogeneity of the evaluation techniques. Finally, the authors offer some suggestions for the appropriate ergonomic analysis of furniture.

Energy Consumption for Furniture Joints during Drilling in Birch Plywood.

The purpose of this study is to support eco-design ideas and sustainable manufacturing techniques by examining the energy consumption related to drilling holes for different furniture connections. The experimental model is a simple piece of furniture made from birch plywood with three different types of joints. Eccentric joints, confirmat screws, and dowel measurements of energy consumption with a CNC drilling and milling machine show different values for every kind of connector. The energy consumption was measured using a portable power quality analyzer, specifically the PQ-box 150 manufactured by A:Eberle GmbH & Co. KG Nürnberg, Germany. This device likely adheres to industry standards for energy measurement, ensuring accurate and reliable results. The measurement process involved recording energy consumption at different stages of the machining process, allowing for the analysis of specific cutting work and total energy consumption for various joint types. Dowels exhibit the lowest energy consumption at 0.105 Wh for one furniture joint, confirmat screws at 0.127 Wh, while eccentric joints, despite their higher energy consumption (0.173 Wh), offer enhanced transportability and assembly flexibility of a piece of furniture. Specific cutting power for one selected piece of furniture was 227.89 J/mm3 for dowels, 190.63 J/mm3 for eccentric joints and 261.68 J/mm3 for confirmat screws.

Mismatch between fixed classroom furniture and anthropometric measurements among university students: Relationships to ergonomic risk.

BACKGROUND: Appropriate arrangement of classroom ergonomics is necessary for maintaining health and improving academic performance, learning, and motivation. OBJECTIVE: We aimed to determine the anthropometric measurements and ergonomic risk levels of students during a handwriting activity on a fixed desk and chair and to analyze the mismatch and relationships between these factors. METHODS: This study included 149 university students (female:73, male:76). Anthropometric measurements (lower and upper extremity length, shoulder height, elbow-rest height, hip-popliteal length, popliteal height, knee height, the distance between tragus and wall, and between acromion and wall) were done with a tape measure. The Rapid Upper Limb Assessment (RULA) tool was conducted to determine the ergonomic risk level while students wrote a standard text on a fixed desk and chair as if they were taking notes in the classroom. The mismatch was evaluated between backrest height and sitting shoulder height, seat height, and popliteal height. The Pearson Chi-Square and the Spearman Correlation test were used for statistical analysis. RESULTS: The median values of the participants' age, height, weight, and BMI were 22 years, 1.70 m, 68 kg, and 23.18 kg/cm2, respectively. Most students had inadequate ergonomic posture while writing on fixed furniture at the university (Median RULA grand score: 4). More mismatches for seat height (54.4%) were found in high ergonomic risk levels but mismatches for backrest height did not follow a similar result. CONCLUSIONS: More investigation should be conducted with prospective studies including interventions like adjustable furniture.

Suicide Rates and Risks Across U.S. Industries: A 29-Year Population-Based Survey.

OBJECTIVE: Suicide rates in the working-age U.S. population have increased by over 40% in the last two decades. Although suicide may be linked with characteristics of workplaces and their industries, few studies have reported industry-level suicide rates. No study has reported suicide rates by industry using nationally representative data. This study estimates suicide risks across industries in the U.S. working population. METHODS: Industry-level estimates of suicide risks require substantial data; we combined 29 years of U.S. suicide data using the National Health Interview Survey (NHIS)-Mortality Linked data from 1986 through 2014, with mortality follow-up through 2015. We conducted survey-weighted Poisson regression analyses to estimate suicide mortality rates and rate ratios across all populations and stratified by gender. All analyses were adjusted first for age, and then for age, employment status, marital status, race/ethnicity, and rurality/urbanicity (demographic-adjusted). Rate ratios compared results for workers in each industry to those for all industries, accounting for the NHIS survey design. RESULTS: A total of 1,943 suicide deaths were recorded. Age-adjusted suicide rates per 100,000 were highest in the furniture, lumber, and wood industry group (29.3), the fabricated metal industry (26.3), and mining (25.8). Demographic-adjusted rates were higher among men than women in most industries. Demographic-adjusted rate ratios were significantly elevated in the furniture, lumber, and wood industries (Rate Ratio, RR = 1.60, 95% confidence interval, CI = 1.18-2.18); chemicals and allied products (RR = 1.49, 95%CI = 1.04-2.13); and construction (RR = 1.21, 95% CI = 1.03-1.41). CONCLUSION: Several industries had significantly high suicide rates. Suicide prevention efforts may be particularly useful for workers in those industries.

The estimation of different body dimensions of children aged 6-11 years for the needs of furniture designers.

BACKGROUND: There are some rules that furniture designers must take into consideration to design ergonomic furniture. The main design principle is the target group for which the furniture will be designed, considering the dimensions of people who use the furniture. OBJECTIVE: The paper presents the correlation between 12 parts of children's body, as well as the proportion between stature and 11 other parts of the body which are used for the purposes of furniture and interior designers. METHODS: Field measurements include: Stature (S), Sitting height (She), Shoulder height (Sh), Popliteal height (Ph), Hip width (Hb), Elbow rest height (Erh), Buttock-popliteal length (Bpl), Buttock-knee length (Bkl), Thigh clearance (Tc), Eye height sitting (Eh), Knee height (Kh) and Shoulder breadth (Sb) to pupils aged 6-11 (grades 1 to 5). The measurements were done in 687 children in 12 primary schools in 4 different regions in Kosovo. RESULTS: The data of the study shows that, in general, there is a correlation (in some parts strong and in some medium) for the measured parts. Also, the study presents the proportion between the stature and other parts of the body which are necessary for the design of children's furniture. CONCLUSION: Using this data will enable furniture designers to easily target the dimensions of the group they will design, even by measuring only one dimension, i.e. stature and then setting the proportions for each piece separately.

Trends in flame retardant levels in upholstered furniture and children's consumer products after regulatory action in California.

In 2013, California revised its upholstered furniture flammability standard TB 117-2013 to improve fire safety without the need for flame retardant (FR) chemicals. Subsequent legislation (SB 1019) required disclosure of FR content. In 2020 California expanded restriction on FR chemicals to include juvenile products and upholstered furniture (AB 2998). To monitor trends in FR use, and assess the effectiveness of the new regulations, we analyzed 346 samples from upholstered furniture (n = 270) and children's consumer products (n = 76), collected pre- and post-regulatory intervention for added FR chemicals (i.e., ∑FR > 1000 mg/kg). Upholstered furniture samples, collected from products before enactment of the new regulations, had a median FR concentration of 41,600 mg/kg (range: 1360-92,900 mg/kg), with 100% of the foam samples and 13.7% of the textile samples containing ∑FR > 1000 mg/kg. Firemaster formulations (FM 550 and FM 600), a mixture of triphenyl phosphate (TPHP), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (BEH-TEBP) and a mixture of isopropyl- or tert-butyl-triphenyl phosphates (ITPs or TBPPs), were the most frequently detected FR (34%), followed by tris(1,3-dichloroisopropyl) phosphate (TDCIPP; 25%), TPHP with a mixture of polybrominated diphenyl ethers (BDE-47, 99, 100, 153 and 154; 20%) and tris(2-chloroethyl) phosphate (TCEP; 11%). Upholstered furniture components collected after enactment of the new legislation had a median FR concentration of 2600 mg/kg (range: 1160-49,800 mg/kg, outlier sample 282,200 mg/kg), with 11.9% of the foam samples and no textile samples containing ∑FR > 1000 mg/kg. Of these samples, tris(1-chloro-2-propyl) phosphate (TCIPP) was the most frequently detected FR (55%), followed by TDCIPP (30%) and Firemaster (FM 550, 15%). No PBDEs were detected in the post-regulatory intervention products. Our initial work on children's products showed 15% of the samples contained ∑FR > 1000 mg/kg. In our post- AB 2998 work, no regulated children's product components failed compliance (i.e., ∑FR > 1000 mg/kg). The data confirm successful adoption of the new regulations with most samples in compliance, demonstrating the efficacy of regulatory intervention. Given these results, environmental FR exposure is expected to decrease as older FR treated consumer products are replaced with FR free products.

Environmental sustainability assessment of wooden furniture produced in Pakistan

Abstract Life cycle assessment was carried out for a conventional wooden furniture set produced in Mardan division of the Khyber Pakhtunkhwa province of Pakistan during 2018-19. Primary data regarding inputs and outputs were collected through questionnaire surveys from 100 conventional wooden furniture set manufacturers, 50 in district Mardan and 50 in district Swabi. In the present study, cradle-to-gate life cycle assessment approach was applied for a functional unit of one conventional wooden furniture set. Production weighted average data were modelled in the environmental impacts modelling software i.e., SimaPro v.8.5. The results showed that textile used in sofa set, wood preservative for polishing and preventing insects attack and petrol used in generator had the highest contribution to all the environmental impact categories evaluated. Total cumulative energy demand for wooden furniture set manufactured was 30,005 MJ with most of the energy acquired from non-renewable fossil fuel resources.

Resumo A abordagem de avaliação do ciclo de vida foi realizada para um conjunto de móveis de madeira convencional produzido na divisão Mardan da província de Khyber Pakhtunkhwa do Paquistão durante 2018-19. Os dados primários sobre entradas e saídas foram coletados por meio de pesquisas por questionário de 100 fabricantes de conjuntos de móveis de madeira convencionais, 50 no distrito de Mardan e 50 no distrito de Swabi. No presente estudo, a abordagem de avaliação do ciclo de vida do berço ao portão foi aplicada para uma unidade funcional de um conjunto de móveis de madeira convencional. Os dados da média ponderada da produção foram modelados no software de modelagem de impactos ambientais, isto é, SimaPro v.8.5. Os resultados mostraram que os têxteis usados no conjunto de sofás, o preservativo de madeira para polir e prevenir o ataque de insetos e a gasolina usada no gerador tiveram a maior contribuição em todas as categorias de impacto ambiental avaliadas. A demanda total acumulada de energia para o conjunto de móveis de madeira fabricado foi de 30.005 MJ, com a maior parte da energia adquirida de recursos de combustíveis fósseis não renováveis.

Environmental sustainability assessment of wooden furniture produced in Pakistan / Avaliação da sustentabilidade ambiental de móveis de madeira produzidos no Paquistão

Abstract Life cycle assessment was carried out for a conventional wooden furniture set produced in Mardan division of the Khyber Pakhtunkhwa province of Pakistan during 2018-19. Primary data regarding inputs and outputs were collected through questionnaire surveys from 100 conventional wooden furniture set manufacturers, 50 in district Mardan and 50 in district Swabi. In the present study, cradle-to-gate life cycle assessment approach was applied for a functional unit of one conventional wooden furniture set. Production weighted average data were modelled in the environmental impacts modelling software i.e., SimaPro v.8.5. The results showed that textile used in sofa set, wood preservative for polishing and preventing insects attack and petrol used in generator had the highest contribution to all the environmental impact categories evaluated. Total cumulative energy demand for wooden furniture set manufactured was 30,005 MJ with most of the energy acquired from non-renewable fossil fuel resources.

Resumo A abordagem de avaliação do ciclo de vida foi realizada para um conjunto de móveis de madeira convencional produzido na divisão Mardan da província de Khyber Pakhtunkhwa do Paquistão durante 2018-19. Os dados primários sobre entradas e saídas foram coletados por meio de pesquisas por questionário de 100 fabricantes de conjuntos de móveis de madeira convencionais, 50 no distrito de Mardan e 50 no distrito de Swabi. No presente estudo, a abordagem de avaliação do ciclo de vida do berço ao portão foi aplicada para uma unidade funcional de um conjunto de móveis de madeira convencional. Os dados da média ponderada da produção foram modelados no software de modelagem de impactos ambientais, isto é, SimaPro v.8.5. Os resultados mostraram que os têxteis usados ​​no conjunto de sofás, o preservativo de madeira para polir e prevenir o ataque de insetos e a gasolina usada no gerador tiveram a maior contribuição em todas as categorias de impacto ambiental avaliadas. A demanda total acumulada de energia para o conjunto de móveis de madeira fabricado foi de 30.005 MJ, com a maior parte da energia adquirida de recursos de combustíveis fósseis não renováveis.

Primary school learners' movement during class time: perceptions of educators in the Western Cape, South Africa.

BACKGROUND: Over the last decade, the efficacy of in-classroom movement to reduce sedentary behaviour has been mainly conducted in high-income, developed countries. To date, there have been no published reports on the perceptions of principals and teachers regarding learners' movement during class time to inform the implementation of classroom-based movement strategies to reduce sedentariness in South Africa. METHODS: A sample of primary school principals and grades 5 and 6 teachers from a range of socio-economic categories participated in this exploratory, descriptive qualitative study in the metro central district of the Western Cape Education Department in South Africa. Transcripts of individual depth interviews (IDIs) with principals and focus group discussions (FGDs) with teachers were coded using Atlast ti 9* software for qualitative analysis. RESULTS: Thirteen principals (13 IDIs) and 24 teachers (6 FGDs) participated in the study. Two main factors influencing in-classroom movement, namely teacher-related and structural factors, were identified. The teacher-related factors pertained to their classroom management practice, knowledge and beliefs about sitting, and management style influenced their role in delivering the curriculum and creating a classroom environment conducive for learning. Classroom factors pertained to classroom size, the number of learners in the class and the ergonomic utility of traditional classroom desks. Institutional expectations and acceptance of learners' behaviour, and teachers' practice were also notable contributing factors that influenced learners' movement during class time. CONCLUSION: Emerging evidence about the efficacy of in-classroom movement on sedentary behaviour and learning outcomes challenges traditional teacher practice that sitting is essential for the delivery of the curriculum and for creating an optimal learning environment. Teacher training about the behaviour control utility of in-classroom movement, and school management and policy supportive of in-classroom movement may encourage fidelity to in-classroom movement strategies.

Strength Classification of Wooden Chairs under Cyclic Loads Based on an Experimental Study.

This study aimed to assess the cyclic load capacity of wooden chairs and subsequently categorize them based on their performance. A diverse selection of chair models was randomly procured from commercial markets. These chairs underwent performance testing, utilizing the cyclic stepped increasing loading method, with adherence to the standards set forth by the American Library Association Technology Reports (ALA). The study evaluated 315 chairs, encompassing 21 chair models. Each chair model underwent five replications of testing across three different loading directions. The resulting dataset of numerical values was subjected to statistical analyses, facilitating the categorization of chairs based on their strength under cyclic loads. Notably, the study revealed substantial variations in the load capacity among different chair models. As a consequence of this investigation, the study established acceptable design load thresholds. For instance, concerning front-to-back loading, it was determined that the chairs with cyclic load capacities ranging from 932 to 1449 N fell within the category of low-strength, between 1450 and 1968 N were classified as medium-strength (suitable for domestic use), and the chairs with cyclic load capacities exceeding 1968 N were considered to possess high strength (intended for hotel lobbies, restaurants, libraries, etc.). Similarly, for back-to-front loading performance, the study identified the chairs with cyclic load capacities between 625 and 895 N as low-strength, 896 and 1167 N as medium-strength, and the chairs with loads surpassing 1168 N as high-strength. The performance thresholds for side thrust loads were as follows: low-strength encompassed the cyclic load capacities ranging from 649 to 934 N, medium-strength spanned the cyclic load capacities between 935 and 1221 N, and high-strength entailed 1222 N and above. Notably, the classification devised in this study is closely aligned with the widely accepted and internationally recognized ALA specification. This strong consistency with global standards reinforces the reliability and applicability of the classification system developed in this research. In conclusion, this study enhances understanding of wooden chair strength performance and offers practical insights that lead to higher-quality products and improved consumer satisfaction. Its recommendations can potentially drive positive change within the industry and benefit manufacturers and consumers.

The Influence of the Content of Recycled Natural Leather Residue Particles on the Properties of High-Density Fiberboards.

During the production of furniture, large amounts of waste materials are generated, which are most often stored in warehouses without a specific purpose for their subsequent use. In highly developed countries, as many as 25 million tons of textile waste are produced annually, of which approximately 40% is non-clothing waste such as carpets, furniture and car upholstery. The aim of this research was to produce and evaluate dry-formed high-density fiberboards (HDF) bonded with urea-formaldehyde resin, 12% resination, with various shares of recycled particles of natural leather used in upholstery furniture production at different contents (1, 5 and 10% by weight). The panels were hot-pressed (200 °C, 2.5 MPa, pressing factor 20 s mm-1). Mechanical properties (modulus of rupture, modulus of elasticity and screw withdrawal resistance) and physical properties (density profile, thickness swelling after water immersion, water absorption and surface absorption) were tested. The density profile and contact angle of natural leather have been also characterized. The results show that increasing the content of leather particles in HDF mostly has a positive effect on mechanical properties, especially screw withdrawal resistance and water absorption. It can be concluded that, depending on the further use of HDF, it is possible to use recovered upholstery leather particles as a reasonable addition to wood fibers in HDF technology.

Analyses of L-Type Corner Joints Connected with Auxetic Dowels for Case Furniture.

Tests were carried out to develop and manufacture various types of auxetic dowels using 3D printing technology. These dowels were then used to connect L-type corner joint specimens for case furniture, and their strength and stiffness were analyzed through experimental, theoretical, and numerical means. In the scope of the study, eight different types of auxetic dowels including two inclusion types, two inclusion sizes, and two dowel hole diameters, as well as a reference non-auxetic dowel, were designed. Accordingly, a total of 180 specimens that included 10 replications for each group were tested; 90 were tested under tension and the remaining 90 were tested under compression. The results demonstrated that the assembly force required for the corner joints connected with auxetic dowels was significantly lower compared to non-auxetic dowels. Furthermore, the numerical and theoretical analyses yielded similar outcomes in this study. Both analyses revealed that the dowels used to connect the corner joints experienced substantial stresses during mounting and bending, ultimately leading to their failure. Upon concluding the test results, it was observed that the corner joints connected with dowels featuring rectangular inclusions exhibited superior performance when compared to those with triangular inclusions. In light of these findings, it can be concluded that further enhancements are necessary for auxetic dowels with rectangular inclusions before they can be utilized as alternative fasteners for traditional dowels.

Mechanical and Chemical Resistance of UV Coating Systems Prepared under Industrial Conditions.

In the upcoming years, it is expected that more furniture will be built from honeycomb panels due to the growing demand for lightweight, long-lasting furnishings. High-density fiberboard (HDF), previously used in the furniture industry as back walls in box furniture or drawer components, has become a popular facing material used in the production of honeycomb core panels. Varnishing the facing sheets of lightweight honeycomb core boards with the use of analog printing technology and UV lamps is a challenge for the industry. The aim of this study was to determine the effect of selected varnishing parameters on coating resistance by experimentally testing 48 coating variants. It was found that the interactions between the following variables were crucial in achieving adequate resistance: lamp power, the amounts of varnish applied, and the number of layers. The highest scratch, impact, and abrasion resistance values were observed for samples with optimal curing provided by more layers and maximum curing with 90 W/cm lamps. Based on the pareto chart, a model was generated that predicted the optimal settings for the highest scratch resistance. Resistance to cold liquids made with a colorimeter increases with lamp power.

Study on the Difference of Superhydrophobic Characteristics of Different Wood Furniture Substrates.

To enhance the stability of wood and decrease restrictions on its use in the furniture industry, hydrophobic modification can be employed to confer waterproof, anti-fouling, and self-cleaning properties. The present study outlines the preparation of silica sol using the sol-gel method, followed by impregnation and chemical vapor deposition methods to modify the sol. After grafting 1H,1H,2H,2H-perfluoro-decyl trichlorosilane (FDTS), hydrophobic and superhydrophobic properties were imparted to the wood substrate. To explore the correlation between the surface properties of the wood substrate and superhydrophobic coatings, the densities, porosities, and surface roughness of various tree species were compared. The results showed that the sol-gel method successfully constructed hydrophobic coatings on different wood substrates, with six samples (poplar, elm, toon wood, paulownia, ashtree, and black walnut) achieving superhydrophobic surfaces, with densities ranging from 0.386 to 0.794 g/cm3, porosity ranging from 13.66 to 42.36%, roughness ranging from 4.660 to 11.244 um, and maximum water contact angle of 165.2°. Whereas beech and rosewood only reach the hydrophobic surface. Although the coatings demonstrated good resistance to water, pollutants, self-cleaning, and chemical agents, further improvements are necessary to enhance mechanical wear resistance.

Optimization of the Cross-Sectional Geometry of Auxetic Dowels for Furniture Joints.

In this study, the aim was to optimize the cross-sectional geometry of auxetic dowels for furniture joints. For this purpose, two different sizes of auxetic dowels were chosen, one for frame- and the other for panel-type furniture joints for designing the cross-sectional geometry. Auxetic patterns that are created on the cross-sectional area cause deficiency of the materials, and this phenomenon decreases the modulus of elasticity (MOE) and increases the member stress. Accordingly, maximum MOE values and minimum Poisson's ratio levels were determined for the optimum strength-auxetic behavior relation by means of a Monte Carlo method. Furthermore, Poisson's ratio of the optimized dowel's cross-section was confirmed with experimental tests, numerical analyses and analytical calculations. As a result, Poisson's ratio values were obtained as negative values and confirmed, which means the dowels designed in this study had auxetic behavior. In conclusion, it could be said that studies should be conducted on the performance of auxetic dowels in both frame and panel furniture joints.

Analysis of the Hanging Actions and Operating Heights of Storage Furniture Suitable for the Elderly.

The current functional scale design of storage furniture which the elderly use does not meet their needs, and unsuitable storage furniture may bring many physiological and psychological problems to their daily lives. The purpose of this study is to start with the hanging operation, to study the factors influencing the hanging operation heights of elderly people undergoing self-care in a standing posture and to determine the research methods to be used to study the appropriate hanging operation height of the elderly so as to provide data and theoretical support for the functional design scale of storage furniture suitable for the elderly. This study quantifies the situations of elderly people's hanging operation through an sEMG test performed on 18 elderly people at different hanging heights combined with a subjective evaluation before and after the operation and a curve fitting between the integrated sEMG indexes and the test heights. The test results show that the height of the elderly subjects had a significant effect on the hanging operation, and the main power muscles of the suspension operation were the anterior deltoid, upper trapezius and brachioradialis. Elderly people in different height groups had their own performance of the most comfortable hanging operation ranges. The suitable range for the hanging operation was 1536-1728 mm for seniors aged 60 or above whose heights were within the range of 1500-1799 mm, which could obtain a better action view and ensure the comfort of the operation. External hanging products, such as wardrobe hangers and hanging hooks, could also be determined according to this result.

A new consensus on reconciling fire safety with environmental & health impacts of chemical flame retardants.

Flame retardants are chemical substances that are intended to mitigate fire safety risks posed by a range of goods including furniture, electronics, and building insulation. There are growing concerns about their effectiveness in ensuring fire safety and the potential harms they pose to human health and the environment. In response to these concerns, on 13 June 2022, a roundtable of experts was convened by the UKRI Six Clean Air Strategic Priorities Fund programme 7. The meeting produced a Consensus Statement that summarises the issues around the use of flame retardants, laying out a series of policy recommendations that should lead to more effective fire safety measures and reduce the human and environmental health risks posed by these potentially toxic chemicals.

Application of 3D Scanning Method to Assess Mounting Holes' Shape Instability of Pinewood.

Swelling and shrinkage anisotropy affect the susceptibility to an assembly of wooden elements by changing designed clearances or interference fits. This work described the new method to measure mounting holes' moisture-induced shape instability and its verification using three sets of twin samples made of Scots pinewood. Each set of samples contained a pair with different grain patterns. All samples were conditioned under reference conditions (relative air humidity-RH = 60% and temperature 20 °C), and their moisture content (MC) reached equilibrium (10.7 ± 0.1%). On the side of each sample, the seven mounting holes of 12 mm in diameter were drilled. Immediately after drilling, Set 1 was used to measure the effective hole diameter with 15 cylindrical plug-gauges with diameters of 0.05 mm step, while Set 2 and Set 3 were separately re-seasoned by six months in two extreme conditions. Set 2 was conditioned with air at 85% RH (reached an equilibrium MC of 16.6 ± 0.5%), while Set 3 was exposed to air at 35% RH (reached an equilibrium MC of 7.6 ± 0.1%). Results of the plug gauge tests highlighted that holes in the samples subjected to swelling (Set 2) increased an effective diameter in the range of 12.2-12.3 mm (1.7-2.5%), while samples subjected to shrinking (Set 3) reduced the effective diameter to 11.9-11.95 mm (0.8-0.4%). To accurately reproduce the complex shape of the deformation, gypsum casts of holes were made. The 3D optical scanning method was used to read the gypsum casts' shape and dimensions. The 3D surface map of deviations analysis provided more detailed information than the plug-gauge test results. Both the shrinking and swelling of the samples changed the shapes and sizes of the holes, but shrinking reduced the effective diameter of the hole more than swelling increased it. The moisture-induced changes in the shape of holes are complex: the holes ovalized with a different range, depending on the wood grain pattern and hole depth, and were slightly extended in diameter at the bottom. Our study provides a new way to measure 3D hole initial shape changes in wooden elements during desorption and absorption.