Indoor definition

The quantity I, (T To(t))dt is named the degree day and is normally calculated for each month but also on a yearly basis. It depends on the climate where the industrial building is situated. This means that different geographic positions have different degree days. From the definition we also see that the degree day depends on the assumed indoor air temperature, which is assumed constant. 

The user must have experience in airflow and indoor air quality analysis and be familiar with the theoretical principles and details upon which indoor air quality analysis is based. Engineering judgment will have to be used for the setup of the building representation and the definition of the input parameters. 

Surprisingly little attention has been given hitherto to the definition of the laboratory. A space has to be specially adapted to deserve that title. It would be easy to assume that the two leading experimental sciences, physics and chemistry, have historically depended in a similar way on access to a laboratory. But while chemistry, through its alchemical ancestry with batteries of stills, had many fully fledged laboratories by the seventeenth century, physics was discovering the value of mathematics. Even experimental physics was content to make use of almost any indoor space, if not outdoors, ignoring the possible value of a laboratory. The development of the physics laboratory had to wait until the nineteenth century... 

A follow-up study on soil radon gas and indoor radon gas was carried out in the Fredericton area. It was found that the individual correlation between soil gas radon and indoor radon on individual properties was not very high, but there was definitely a regional correlation. The reasons for the low individual correlation can be traced to other important variables such as age and type of construction of the homes. 

The presence of water does not only create conditions for the existence of an electrolyte, but it acts as a solvent for the dissolution of contaminants [10], Oxygen plays an important role as oxidant element in the atmospheric corrosion process. The thickness of the water layer determines the oxygen diffusion toward the metallic surface and also the diffusion of the reaction products to the outside interface limited by the atmosphere. Another aspect of ISO definition is that a metallic surface is covered by adsorptive and/or liquid films of electrolyte . According to new results, the presence of adsorptive or liquid films of electrolyte perhaps could be not in the entire metallic surface, but in places where there is formed a central anodic drop due to the existence of hygroscopic particles or substances surrounded by microdrops where the cathodic process takes place. This phenomenon is particularly possible in indoor conditions [15-18],... 

The use of catalysts for exploiting renewable energy sources, producing clean fuels in refineries, and minimizing the by-product formation in industry also fall within the definition of environmental catalysis. In the future, the continuous effort to control transport emissions, improve indoor ah quality, and decontaminate polluted water and soil will further boost catalytic technology. All in all, catalysts will continue to be a valuable asset in the effort to protect human health, the natural environment, and the existence of life on Earth. 

This sets the context for examining air quality in museums currently important discussions hinge around the identification of frameworks, definitions and the forms of guidelines or standards for indoor air quality from the perspective of cultural heritage (Tetreault, 2003 Grzywacz, 2006). These will be discussed in Section 12.9.1. 

Additionally, there is the crucial consideration of the extent to which such external exposure translates into internal exposure or body burden. To date, there is only one paper that makes a definitive link between indoor contamination (specifically of dust) and body burden for PBDEs (Wu et ah, 2007). While there are few data relating to such bioavailability issues for indoor air and dust, the situation is not appreciably less certain than for dietary exposure. An important recent study (Huwe et al, 2008) has compared the bioavailability of PBDEs administered to rats in both indoor dust and in corn oil. While there was considerable congener-specific variation in uptake, there were no significant differences in uptake for a given congener regardless of whether it was administered in dust or corn oil. 

Environmental criteria have been established for many of these, but the utility and applicability of such criteria for indoor environments is controversial for at least four reasons. Eor example, the goals of the threshold limit values often do not include preventing irritation, a primary concern in indoor environments with requirements for close eye work at video display terminals. For most of the pollutant categories, the problem of interactions, commonly termed the multiple contaminants problem , remains inadequately defined. Even for agents that are thought to affect the same receptor, such as aldehydes, alcohols, and ketones, no prediction models are well established. Finally, the definition of representative compounds for measurement is unclear. That is, pollutants must be measurable, but complex mixtures vary in their composition. It is unclear whether the chronic residual odor annoyance from environmental tobacco smoke correlates better with nicotine, particulates, carbon monoxide, or other pollutants. The measure total volatile organic compounds is meanwhile... 

The studies just cited address the risk of developing lung cancer following exposure to radon, asbestos, and tobacco. Though estimating these risks are complicated by human exposures to other environmental pollutants, both indoors and outdoors, I42 44 these and other similar studies do definitively establish the enhanced effects of exposure to mixtures on the development of lung cancer and other cancers. This subject is discussed further in Chapter 21. 

Only a few of the studies estimated the TVOC of the microenvironments reported [42,67,71] or focussed on complaint buildings [67,72]. Because different definitions and methods of TVOC were employed to estimate the values quoted, it is difficult to make direct interstudy comparisons nevertheless it appears that TVOC can range from 10 ggm to several thousand micrograms per cubic metre in indoor environments. 

The procedure further recommends that as many VOCs as possible should be quantified in the analytical window bounded by the retention times of hexane and hexadecane, and that these VOCs should as far as possible include the 64 VOCs that are of special interest to the European Community [2]. A major shortcoming of the recommendation is that not all VOCs present in indoor air are included in the approach. For example, important indoor VOCs like 2-propanol, 2-methylpentane, 3-methylpentane and butanal elute before hexane while texanolisobutyrate elutes after hexadecane [60]. It was also expected that the definition would enhance interlaboratory TVOC values, classification and screening of indoor materials, and the identification of problems with ventilation design, indoor activities or materials [12]. However, De Bortoli et al. [73] observed large variances in interlaboratory studies performed with the approach. Nevertheless, it has been adopted in many recent indoor air studies [10,60,74]. 

Ultrafine particles have been defined as those, which are smaller than 0.1 pm. Another classification is into submicrometre particles, which are smaller than 1 pm, and supermicrometre particles, which are larger than 1 pm. The terminology that has been used in the wording of the ambient air quality standards, and also for characterisation of indoor and outdoor particle mass concentrations, includes PM2.5 and PM fractions and the total suspended particulate (TSP). PM2.5 (fine particles) and PM, are the mass concentrations of particles with aerodynamic diameters smaller than 2.5 and 10 pm, respectively (more precisely the definitions specify the inlet cutoffs for which 50% efficiency is obtained for these sizes). TSP is the mass concentration of all particles suspended in the air. There have been references made in the literature to PMj or PMq 1 fractions, which imply mass concentrations of particles smaller than 1 and 0.1 pm, respectively. These terms should be used with caution, as particles below 1 pm, and even more those below 0.1 pm, are more commonly measured in terms of their number rather than their mass concentrations, and therefore these terms could be misleading. 

The depth of current concern for definition and control of the indoor air quality problem is shown by the number of federal agencies that are involved in evaluating and regulating this area in the USA alone. The 16 agencies that form the Interagency Committee for Indoor Air Quality in the US(11) include the Environmental Protection Agency, (Co-chair), Department of Energy, (Co-chair), Department of Health and Human Services, (Co-chair), Consumer Product Safety Committee, (Co-chair), Bonneville Power Administration, Department of Defense, Federal Trade Commission... 

VOC and TVOC (Table 3.1-2) concentrations had been measuied in relatively few buildings with occupant complaints of poor indoor air quality (lAQ), limiting their interpretation. Higher concentrations were observed in some complaint buildings, but not others. In view of the potentially multi-factorial nature of these complaints, better controlled studies (and TVOC definitions) are necessary to test the relationship between VOC concentrations and occupant complaints (Norback et al., 1990 1995). 

There is some utility in having a definitive list of VOCs relevant to indoor air exposure. For example, analytical parameters can be tuned to suit defined compounds and a database of toxicological effects can be developed. The European Commission (1994) has recommended such a list (Table 3.1-6) based on field data, emission studies and frequency of presence in indoor air. This includes many of the VOCs from Table... 

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