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Abstract. The paper presents the thermal resistance characteristics of walls with multilayer reflective insulation. The tests have been performed using a heat flow meter to determine the resistivity of the layers simulating partition walls in buildings. A modification of the structure has also been proposed and analysed with a view to increase the thermal resistance and, consequently, reduce the heat flux transferred through the walls. Consequently, walls produced with layers that ensure higher thermal insulation lead to better thermal performance properties of the whole buildings, which reduce heating/cooling costs throughout the year.

The amount of particulate matter present in Bretschneider's cardioplegic solution (HTK) was assessed by laser-mediated particle counting. Permissible levels of contaminant particles with a distribution of diameters between 0.2 and 20 microns were found. A significant further increase in the particle count was observed when the fluid was administered for clinical use, which resulted in the additional release of particles from, for example, the infusion kit, which included an in-line filter with pores of 270 microns. Filtration of the HTK solution by a terminal inline filter (0.2 micron) significantly reduced the number of particles. In order to determine the chemical composition and the potential hazards of the particulate material we used scanning electron microscopy in combination with energy dispersive X-ray analysis and transmission electron microscopy to examine specimens taken from heart tissue obtained from Göttinger minipigs after cardioplegia and from humans undergoing mitral valve replacement after cardioplegia and reperfusion. Particles of various diameters were found either to be plugging coronary capillaries, to be adherent to the endothelial layer, or to be engulfed by polymorphonuclear (PMN) granulocytes, which appeared to be activated. Some of the PMN granulocytes were apparent in the endothelial layer. It is recommended, therefore, that a terminal in-line filter (0.2 micron) should be routinely used.

In the first part of this series, we discussed that the building structure, energy efficiency, indoor environmental quality, and moisture management all need to be considered simultaneously to ensure durability of materials and control cost of near-zero energy buildings. These factors must be addressed through contributions of the whole design team. It is also evident that building physics must take an active role in development of near-zero energy buildings. The need to ensure good indoor environment and durability of materials and limit the cost of buildings led to integrated design process that now is typical in Canada for design of low-energy buildings. Furthermore, interactions between energy efficiency, quality of indoor environment and moisture management led us to introduce a concept of “environmental control.” In the meantime, we made an unexpected observation—Vancouver dwellings in 2002 use the same amount of energy as 1920 uninsulated masonry buildings erected in the same location. We concluded that despite having advanced technology, our lack of vision prevents us from an effective use of this technology. With the quest for sustainable buildings, we should learn more from termites, who appear to master the art of hygrothermal control better than humans as they are capable of maintaining highly stable interior comfort zone without heating, ventilating, and air-conditioning equipment. Nevertheless, whatever progress is achieved in new low-energy buildings, it is lost when rehabilitating existing buildings because there an owner will typically do one step at a time. If the financial constraints do not allow for more, this first step should be an integrated action that includes a combination of insulation and heating systems.

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