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Energy efficiency measures in residential buildings typically include changes in ventilation and heating systems, and increased thermal insulation of the building envelope. The expected energy efficiency is not always reached, despite large knowledge and professional implementation of each separate measure. There is a lack in understanding of how technical systems interact, and how the occupants are influenced by and in turn influence the systems by their behaviour. A holistic view and a transdisciplinary research approach are needed to understand relevant interactions and propose integrated energy efficiency measures. The aim of this paper is to reveal challenges in transdisciplinary research projects that include real world studies on both humans and technical systems with measurements before and after renovation of multifamily housing. It is based on experiences from the PEIRE-project (People, Environment, Indoor, Renovation, Energy) carried out by a research team with expertise on environmental psychology, human behaviour, interaction design, universal design, building physics, building services, thermal comfort, aerosol technology, exposure assessment, acoustics, daylight, and complex thinking. Differences in theoretical bases and methodology needed to be dealt with. Metatheory building could help with the transition from a multi- to a transdisciplinary understanding.

Owing to giving more stable and repeatable test results than human tests, thermal manikin is widely used in fields like clothing, automobile, building, aerospace, etc. Thermal manikin is promising and reliable to characterize both static and dynamic heat and moisture exchange in human body-clothing-environment system, particularly in extremely hot or cold environments. Nowadays, there are hundreds of thermal manikins with different functions in the world and their functions become more and more humanlike, e.g., can better simulate human thermoregulations. In this chapter, we reviewed and concluded the types of manikin in terms of anthropometric data, number of the body segment, construction, function, feedback system, working principle, control mode, etc. The state of the art and future trends of the advanced tool were summarized. With the development of manufacture technology, computer science and signal processing capacity, a more humanlike simulator can predict physiological and psychological responses of human body in various conditions. It can make significant contribution in realistic performance evaluation for protective clothing in hazardous environments, as an alternative for human beings.

in Undetermined Abstract The impact of heat waves arising from climate change on human health is predicted to be profound. It is important to be prepared with various preventive measures for such impacts on society. The objective of this study was to investigate whether personal cooling with phase change materials (PCM) could improve thermal comfort in simulated office work at 34°C. Cooling vests with PCM were measured on a thermal manikin before studies on human subjects. Eight male subjects participated in the study in a climatic chamber (T(a) = 34°C, RH = 60%, and ν(a) = 0.4 m/s). Results showed that the cooling effect on the manikin torso was 29.1 W/m(2) in the isothermal condition. The results on the manikin using a constant heating power mode reflect directly the local cooling effect on subjects. The results on the subjects showed that the torso skin temperature decreased by about 2-3°C and remained at 33.3°C. Both whole body and torso thermal sensations were improved. The findings indicate that the personal cooling with PCM can be used as an option to improve thermal comfort for office workers without air conditioning and may be used for vulnerable groups, such as elderly people, when confronted with heat waves. PRACTICAL IMPLICATIONS: Wearable personal cooling integrated with phase change materials has the advantage of cooling human body's micro-environment in contrast to stationary personalized cooling and entire room or building cooling, thus providing greater mobility and helping to save energy. In places where air conditioning is not usually used, this personal cooling method can be used as a preventive measure when confronted with heat waves for office workers, vulnerable populations such as the elderly and disabled people, people with chronic diseases, and for use at home. (Less)

Current research on slipperiness of footwear has mainly focused on floors and lubricated floors. Slips and falls on icy and snowy surfaces involve not only outdoor workers, but also pedestrians and the general public; and occur in cold regions and in winter season in many parts of the world. However, in comparison with the size of the problem, research on slips and falls on icy and snowy surfaces has been scarce. The objective of this paper is to explore the slip resistant properties of footwear (soling materials, roughness and hardness) on ice. The coefficients of kinetic friction of four different soling materials (synthetic rubber, nitrile rubber, natural rubber and polyurethane) were measured on ice (-12 degrees C). The outsole roughness and hardness were also measured. Results showed that the polyurethane soling did not perform better than synthetic rubber, nitrile rubber and natural rubber on pure hard ice (-12 degrees C). Soling roughness was positively correlated with the coefficient of kinetic friction. The most slip resistant soling material (polyurethane) on floors and lubricated floors may not provide sufficient slip resistance on ice.

Current research on slips and falls has mainly focused on floors and/or contaminated floors. Although icy and snowy surfaces near melting temperature are more slippery, more important still, slip and falls on icy and snowy surfaces involve not only outdoor workers, but also pedestrians and the general public; and occur in cold regions and in the winter season in many parts of the world. However, in comparison with the size of the problem, research work done so far in this area has been limited. The objective of this paper is to present a systems perspective of slip and fall accidents, with special focus on its occurrence on icy and snowy surfaces. In order to explore the aetiology of slip and fall accidents further, and to provide the basis for prevention, the authors put forward a systems model towards the slips and falls on icy and snowy surfaces based on a review of literature and current knowledge. Various contributing factors are systematically discussed to highlight the multi-factorial nature of the problem, providing the possibility of a multi-faceted approach to reach systematic prevention. Unresolved issues related to slips and falls on ice and snow are also identified, which necessitate further research.

It is a complex task to find optimal protective clothing to prevent the spread of Ebola virus disease (Martin-Moreno et al., 2014; Ryschon, 2014). The fear of getting infected is an obstacle for recruiting healthcare workers. In addition, the current design of protective clothing might curtail their working capacity severely in the hot and humid climate of West Africa and, in addition, paradoxically increase the risk of infection. Emergency work in full protective clothing including respiratory mask may lead to extreme heat stress in the hot climates resulting in shortened work time, dehydration, reduced professional judgement, and exhaustion. This increases risk of infection of health stuff (WHO, 2014). In Monrovia, Liberia, daytime maximum temperatures in the end of the year often reach 30–31°C, and the temperatures will be higher January to May, the hot season (Kjellstrom et al., 2014; http://climatechip.org/). In order to manage this heat stress, the workers need breaks (Kjellstrom et al., 2009). This leads to a frequent need to remove the protective gear, which involves an increased risk of infection. The multiple steps to remove the suit can take up to 30min (Kitamura, 2014). The modified Predicted Heat Strain (ISO 7933, 2004) model was used to indicate the expected work times (Fig. 1). The estimation was made based on the following assumptions. Standard man was chosen for the model calculations. Medium heavy activity (300W) was taken as the average work rate. The core temperature limit to cease such emergency work was set to 38.5°C. Three clothing types with different moisture permeability (i m) were selected for comparison: an impermeable outer layer (i m = 0.00), a semipermeable outer layer (i m = 0.07), and a relatively tight but still permeable outer layer (i m = 0.20). The basic clothing insulation in all cases was theoretically taken as 1 clo (0.155 m2K W−1) for comparative purposes. In all air temperature conditions, the other environmental factors were kept constant. Ambient water vapour pressure was set to 3.0 kPa, air velocity/body motion was 1 m s−1, and there was assumed no radiation effect present (work indoors or in shade). 1 Continuous work times for a work rate of 300W at different air temperatures before reaching a core temperature limit at 38.5°C in clothing with different moisture permeability (i m). The chosen work load in impermeable and semipermeable clothing allows 40min or shorter exposure during the hottest periods (Fig. 1) until the core temperature exceeds the suggested safe limit for occupational exposure. Higher core temperature is associated with decreased mental performance and increased misjudgement and mistakes (O’Neal and Bishop, 2010). Maximizing the moisture permeability and minimizing the clothing layers worn beneath the protective gear, provided that it should be resistant to penetration by body fluids, is a simple way of preventing heat stress and increasing the time spent inside the gear. However, dehydration and water intake must also be considered during extended exposures. A heat stress management program including rehydration should be an essential part of the overall health and safety program in any case. A desirable addition would be personal cooling used inside the protective clothing, such as cooling vests with ice or phase change materials (PCMs; Gao, 2014) or filtered ventilated coveralls (Kuklane et al., 2012). This may prolong working time to about 2h and reduce the number of gear changes per day. With 2-h work time in protective gear, the number of required personnel could be halved with possible decrease in contaminated waste. The final choice of the cooling method depends on specific air temperature and humidity. Increasing air temperature and, especially, humidity do reduce the effectiveness of air cooling and increase the benefits of PCM products. The use of PCMs requires freezers or cool areas for solidification after use. Cooling vests with ice are the cheapest and electricity for freezers is required. Power is one of the basic resources to provide healthcare and to cope with epidemics. Otherwise, the other types of PCM, e.g. Glauber’s salt or organic hydrocarbons/wax, with melting/solidifying temperature at about 28°C are available. For workers’ recovery after heat exposure, a room with air temperature below 27°C is recommended. The room or connected facilities could be used for PCM solidification storage. If still unavailable, then the melted PCM can be solidified in a relatively cooler water bath (using underground/well water, etc.), in an underground cave or in a cooler area during night. The higher the melting temperatures are, the less effective cooling is. However, if the temperature gradient is about 6°C or greater, the PCM can still provide a cooling effect. Considering cooling effect in ventilated garments, the provided air flow should be above 100 l min−1. There are filtered fan systems available on the market that manage the flows up to and above 200 l min−1 with the battery power lasting at least 5–8h (recharging takes about 2h). Ventilated systems (positive pressure suits) may allow even drinking water in the suit and that may prolong the work time even more. Table 1 gives a rough cost comparison of the present and a possible future protective clothing system based on 1-day (8-h) shift. It takes into account only the equipment cost. Estimation is based on the work time predictions given in Fig. 1 for the hottest work periods, i.e. 30min for the impermeable set and 2h for the new system that prolongs work period by higher permeability or by use of a cooling device. In both cases, similar final core temperatures are expected to limit the exposure. Also, it is expected that both sets take 30min for dressing, 30min for undressing, and require 30min for recovery between the work periods. As it can be seen the equipment cost of a new, theoretically even a 10 times more expensive solution is almost 3 times higher for a day. Table 1. Comparison of the equipment cost of the present and a possible, 10 times more expensive protective clothing system based on 1-day (8-h) shift. Assumed work time is 30min for present and 2h for the new system. In both cases, expected donning, doffing, ... Simultaneously, there are also other benefits with an actively cooling clothing system. The personnel need to cover one workstation is halved. The personnel have even extra time (about 30min) between the shifts to help with any other tasks or for additional recovery. Due to fewer times of dressing–undressing (16 + 16 times 30min versus 4 + 4 times 30min for present respective new system), there is also less need for assistance and disinfection during these periods. There will be less contaminated waste or fewer amounts of products to be cleaned. The new systems are meant to be reusable (extra costs for decontamination procedures have to be considered) compared to present, supposedly disposable systems, and already 2.5 times reuse will even up the equipment costs at the estimated prices. Infection risks are diminished due to the reduced need for undressing and cleaning procedures. In conclusion, reducing the risk of infection among the front-line healthcare workers and allowing a doubling of their work capacity could be a critical factor to successfully contain the epidemic. Considering that this epidemic is not the last, and with warmer climate both the epidemics are expected becoming more frequent, and conditions to fight them more severe (IPCC, 2013), then the testing and evaluation for selection of the optimal equipment is required long before missions are set out.

Prevention of slip hazard in frozen environments is not paid much attention. Current winter and safety footwear does not provide sufficient slip resistance and appropriate wearability for use on icy surfaces. The objectives of this study were to assess the integration of slip resistance, thermal insulation, and wearability of footwear used on icy surfaces, and the anti-slip effect of materials spread on ice using outdoor walking trials. Twenty-five subjects wore four types of footwear walking on five different icy surfaces. A five-point rating scale was used recording wearer's perceptions of slipperiness, thermal comfort and wearability. The results showed that pure ice was perceived as very slippery. Spreading sand (180 g/m2) greatly decreased the slipperiness. Slip resistance, thermal insulation and wearability of footwear tested were not properly integrated, and were ranked differently. The tested winter and safety footwear did not provide sufficient slip resistance and good wearability. In addition to thermal insulation, prevention of slip and fall hazard by improving anti-slip property and wearability must also be priorities for development of footwear for use in cold climate.

Slips and falls on icy roads often result in fractures or sprains and is a major problem in Nordic countries. Walking trials by 25 subjects wearing four types of winter shoes on five different icy walking surfaces provided subjective and objective measures of tendency to slip and number of slips, respectively. Since friction is a major determinant of a slip, the influence of material spread on icy surfaces, the surface temperatures and the shoe soling characteristics versus the Coefficient of Friction (COF) of the shoes were measured. Sand and gravel on icy roads had positive effects on improving COF. The study revealed that the aetiology of slips and falls is multi-faceted and attempts to solve the problem must adopt a systems approach. Perception of risk, aging, training, experience and postural balance are other factors to be considered in preventing slips and falls. Future research should concentrate on the degree of impact of each factor to the aetiology of slips and falls, which can help to decide priority action in preventing slips and falls. Relevance to industry The personal protective devices used by outdoor workers during winter season have to provide two types of protection, namely, protection from an occupational hazard and protection from the cold climate. Safety shoes used on snow or ice covered surfaces add a third type of protection, namely, an anti-slip quality of the shoe. The 3rd protection can be achieved from among other things, by improving the friction of the shoe soles.

The objectives of this study are to assess the perception of slipperiness, thermal comfort, and wearability of footwear used on icy surfaces, and the anti-slip effect of materials spread on ice using outdoor walking trials. Twenty-five subjects wore four types of footwear walking on five different icy surfaces. Five-point rating scale was used recording wearer's perception. The results showed that pure ice was perceived as very slippery. Spreading sand (180 g/m2) greatly decreased the slipperiness. Slip resistance, thermal insulation and wearability of footwear chosen were not properly integrated, and were ranked different in four types of footwear. In addition to thermal insulation, prevention of slip and fall hazard by improving anti-slip property and wearability must also be priorities for development of footwear for use in cold climate.

Sorting mail into racks for postmen is visually demanding work. This can result in backward inclination of their heads, especially more pronounced for those who use progressive addition lenses.To evaluate the effects of customized working spectacles on the physical workload of postmen.Twelve male postmen sorted mail on two occasions: once using their private progressive spectacles and once using customized sorting spectacles with inverted progressive lenses. Postures and movements of the head, upper back, neck, and upper arms were measured by inclinometry. The muscular load of the trapezius was measured by surface electromyography.With the customized sorting spectacles, both the backward inclination of the head and backward flexion of the neck were reduced (3°), as well as the muscular load of the right upper trapezius, compared to sorting with private spectacles. However, with the sorting spectacles, there was a tendency for increased neck forward flexion, and increased sorting time.The reduction in work load may reduce the risk for developing work-related musculoskeletal disorders due to the positive reduction of the backward inclination of the head. But the tendency for increased neck forward flexion may reduce the positive effects. However, the magnitude of the possible reduction is difficult to predict, especially since quantitative data on exposure-response relationships are unknown. Alternative working spectacles with inverted near progressive lenses ought to be evaluated. They should still result in a positive reduced backward inclination of the head and may not cause any increased forward flexion.

Protective clothing protects wearers from hostile environments, including extremes of heat and cold. Whilst some types of protective clothing may be designed primarily for non-thermal hazards (e.g. biological hazards), a key challenge in all protective clothing remains wearer comfort and the management of thermal stress (i.e. excessive heat or cold). This book reviews key types of protective clothing, technologies for heating and cooling and, finally, modeling aspects of thermal stress and strain. Explores different types of protective clothing, their uses and their requirements, with an emphasis on full-scale or prototype clothing, including immersion suits, body armour and space suits Considers novel and commercial technologies for regulating temperature in protective clothing, including phase change materials, shape memory alloys, electrically heated clothing and air and water perfusion-based cooling systems Reviews the human thermoregulatory system and the methods of modelling of thermal stress in protective clothing through various conditions, including cold water survival and firefighting. (Less)

The various types of phase-change materials (PCMs), which absorb or release stored latent heat when they change phases causing cooling and warming effects, are described and the working principles are outlined. The various ways of incorporating PCMs into textiles for protective clothing are explored, and critical factors identified that determine the effectiveness of PCM cooling and warming effects. Examples of applications are given. Standards and testing, future trends and challenges are discussed.

Standard No. EN 15831:2004 provides 2 methods of calculating insulation: parallel and serial. The parallel method is similar to the global one defined in Standard No. ISO 9920:2007. Standards No. EN 342:2004, EN 14058:2004 and EN 13537:2002 refer to the methods defined in Standard No. EN ISO 15831:2004 for testing cold protective clothing or equipment. However, it is necessary to consider several issues, e.g., referring to measuring human subjects, when using the serial method. With one zone, there is no serial-parallel issue as the results are the same, while more zones increase the difference in insulation value between the methods. If insulation is evenly distributed, differences between the serial and parallel method are relatively small and proportional. However, with more insulation layers overlapping in heavy cold protective ensembles, the serial method produces higher insulation values than the parallel one and human studies. Therefore, the parallel method is recommended for standard testing.

Modern technology makes garments smart, which can help a wearer to manage in specific situations by improving the functionality of the garments. The personal heating garment (PHG) widens the operating temperature range of the garment and improves its protection against the cold. This paper describes several kinds of PHGs worldwide; their advantages and disadvantages are also addressed. Some challenges and suggestions are finally addressed with regard to the development of PHGs.

Thermal manikins are useful tools to study clothing comfort and environmental ergonomics. The simulation of sweating can be achieved by putting a highly wicking stretchable knit fabric “skin” on top of the manikin. However, the addition of such a fabric skin makes it difficult to accurately measure the skin surface temperature. Moreover, it takes considerable amount of time to measure the fabric skin surface temperature at each test. At present the attachment of temperature sensors to the wet fabric skin is still a challenge. The distance of the sensors to the fabric skin could significantly influence the temperature and relative humidity values of the wet skin surface. Hence, we conducted an intensive skin study on a dry thermal manikin to investigate the relationships among the nude manikin surface temperature, heat losses and the fabric skin surface temperature. An empirical equation was developed and validated on the thermal manikin „Tore‟ at Lund University. The empirical equation at an ambient temperature 34.0 oC is Tsk =34.00-0.0103HL. This equation can be used to enhance the prediction accuracy of wet fabric skin surface temperature and the calculation of clothing evaporative resistance.

Cold protective clothing was studied in 2 European Union projects. The objectives were (a) to examine different insulation calculation methods as measured on a manikin (serial or parallel), for the prediction of cold stress (IREQ); (b) to consider the effects of cold protective clothing on metabolic rate; (c) to evaluate the movement and wind correction of clothing insulation values. Tests were carried out on 8 subjects. The results showed the possibility of incorporating the effect of increases in metabolic rate values due to thick cold protective clothing into the IREQ model. Using the higher thermal insulation value from the serial method in the IREQ prediction, would lead to unacceptable cooling of the users. Thus, only the parallel insulation calculation method in EN 342:2004 should be used. The wind and motion correction equation (No. 2) gave realistic values for total resultant insulation; dynamic testing according to EN 342:2004 may be omitted. Validerad; 2007; 20070904 (pafi)

Slips and falls and associated outdoor injuries are prevalent in cold climates. The objectives of this field investigation were to describe the consequences of slips and falls on ice and snow and the associated injuries, to assess the risks of various icy and snowy surfaces, to identify design needs of footwear, and to ascertain preventive measure preferences of outdoor workers. The organizations investigated were a newspaper delivery service, a military regiment, mining and construction industries. The results showed that fall events occur most frequently on ice covered with snow. This is due to the difficulty of perceiving hidden risks in order to adjust gait strategies. The professional footwear provided does not provide enough protection against slips and falls. Slip resistant properties are ranked as one of the top requirements by the users. Their most preferred preventive measures are footwear with anti-slip properties and the application of anti-slip materials, such as sand or salt.