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Indoor analysis

Sihcone contamination has been impHcated as a cause of failure in telephone switching systems and other devices that contain relay switch contacts (507). Analysis of airborne particulates near telephone switching stations showed the presence of siUcones at these locations. Where the indoor use of sihcones is intentionally minimised, outdoor levels were found to be higher than inside concentrations (508). Samples of particulates taken at two New Jersey office buildings revealed sihcone levels that were considerably higher indoors than outdoors. In these cases, indoor sihcone aerosols are beheved to be generated primarily by photocopiers, which use sihcone fuser oils. [Pg.61]

Because the system likely is nonisothermal, the analysis of a closed-desiccant system requites knowledge of the temperature of the desiccant as well as the dew point (ice point) or water concentration (partial pressure) specification. Indeed, the whole system may undergo periodic temperature transients that may compHcate the analysis. Eor example, in dual-pane windows the desiccant temperature is approximately the average of the indoor and outdoor temperatures after a night of cooling. However, after a day in the sun, the desiccant temperature becomes much warmer than the outdoor temperature. When the sun sets, the outdoor pane cools quickly while the desiccant is still quite warm. The appropriate desiccant for such an appHcation must have sufficient water capacity and produce satisfactory dew points at the highest temperatures experienced by the desiccant. [Pg.509]

Measurement of specific chemical or biological contaminants can be very expensive. Before expending time and money to obtain measurements of indoor air pollutants, you must decide how the results will be used (e.g., comparison to standards or guidelines, comparison to levels in complaint-free areas) what substances(s) should be measured where to take, samples when to take samples what sampling and analysis method to use so that the results provide useful information. [Pg.225]

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. [Pg.1084]

In industrial ventilation the majority of air velocity measurements are related to different means of controlling indoor conditions, like prediction of thermal comfort contaminant dispersion analysis adjustment of supply airflow patterns, and testing of local exhausts, air curtains, and other devices. In all these applications the nature of the flow is highly turbulent and the velocity has a wide range, from O.l m in the occupied zone to 5-15 m s" in supply jets and up to 30-40 m s in air curtain devices. Furthermore, the flow velocity and direction as well as air temperature often have significant variations in time, which make measurement difficult. [Pg.1152]

Applications In contrast to El ionisation, ion-molecule reactions in IMR-MS usually avoid fragmentation [71]. This allows on-line multicomponent analysis of complex gas mixtures (exhaust gases, heterogeneous catalysis, indoor environmental monitoring, product development and quality control, process and emissions monitoring) [70], It should easily be possible to extend the application of the technique to the detection of volatiles in polymer/additive analysis. [Pg.367]

The Florida data reported by Geomet have been evaluated and the houses are listed in order of highest measured indoor radon levels. This analysis is shown in Table 31.3.4445... [Pg.1289]

Outdoor lead dust was found to be a more potent contaminant of children s hands than indoor lead dust at day care centers in New Orleans boys, in general, had higher hand lead levels than girls. The conclusions were based on lead analysis of hand wipe samples taken before and after children played outdoors at four different day care centers (a private inner-city site, a private outer-city site, a public inner-city site, and a public outer-city site). The private inner-city site had a severely contaminated outdoor play area with measured soil lead concentrations ranging from 287 to 1,878 mg/kg. The outdoor play area at the public inner-city site, where children exhibited the lowest hand lead measurements of any site in the study, had been completely paved over with concrete or rubberized asphalt and had well-maintained equipment (Viverette et al. 1996). [Pg.429]

Moed, B.A., Nazaroff, W.W., Nero, A.V., Schwehr, M.B., and Van Heuvelen, A., Identifying Areas with Potential for High Indoor Radon Levels Analysis of the National Airborne Radiometric Reconnaissance for California and the Pacific Northwest, Report LBL-16955, Lawrence Berkeley Laboratory, Berkeley CA (1984). [Pg.34]

The only information presently available on the national frequency distribution of indoor radon levels is a 1984 analysis by Nero at the Lawrence Berkley Laboratory (Nero et al., 1984). Using data from about 500 houses, Nero developed a frequency distribution of radon levels in U.S. single family houses. This distribution is characterized by a geometric mean of 0.9 pCi/L and a geometric standard deviation of 2.8. [Pg.70]

However, since the data used in this study are subject to the limitations and uncertainties cited above, the results of this analysis represent only a very rough approximation of the national frequency distribution of indoor radon levels. EPA s national survey will seek to more accurately characterize this distribution through use of a larger sample size, a statistically based survey design, and consistent, quality assured sample collection and measurement procedures. [Pg.70]

Due to the superposition of various other biological, physiological and physical parameters used in modelling, the published exposure-dose conversion factors range from 2 to 120 mGy per WLM. However, a sensitivity analysis indicated that for most indoor exposure situations compensatory effects can reduce this range to about 5 to 10 mGy/WLM for the indoor situations occurring most frequently (OECD/NEA, 1983). [Pg.437]

Sunbeds with fluorescent lamps that emit in the UVA and UVB are used for indoor tanning. They are supposed to simulate the solar UV spectrum and have therefore similar effects on the human skin. However, the intensity of radiation is often not monitored, and excessive exposure may cause serious dermatological health problems. A more detailed analysis reveals that the long-wave UV (UVA) is mainly responsible for the tanning while UVB radiation tends to be more dangerous. [Pg.167]

ASTM. 1991. Standard practice for sampling and analysis of pesticides and polychlorinated biphenyis in indoor atmospheres. American Society for Testing and Materials. ASTM designation D4861-91. p366-379. [Pg.236]

Nov Introduction to Marketing Business Plan, Business Registration Computer Simulation (1) CFD Analysis of air flow and pollutant dstribution in indoor (2) Powder processing (3) CAD/CAM for product design. Detailed Process Design and Simulation ... [Pg.351]

Feb Competition and Business Strategy Product Design (1) Indoor air survey (2) Prototype Chemical Design and Processing (1) Adsorbents (2) Catalysts. Process Safety Analysis Process Control and Instrumentation Environmental Impact Assessemsnt Report Writing... [Pg.351]

A method was developed to assess TSNA in indoor air polluted with tobacco smoke. Collection was followed by enrichment, concentration and desorption, and analysis by capillary GC-TEA. The concentration of A -nitrosonomicotine (299) was 0-23 pg/L, that of A -nitrosoanatabi nc (302) was 0-9 pg/L and that of 300 1-29 pg/L. Thus, nonsmokers can be exposed to highly carcinogenic TSNA616. [Pg.1151]

Also, Petty et al. (2002) performed an in depth analysis of the OCP fraction of SPMD extracts by gas chromatography-mass spectrometry (GC-MS) resulting in the tentative identification of about 400 airborne organic chemicals, which were not present in SPMD field blanks. The OCP fraction represents only one of several enriched fractions from SPMD samples. Table 8.1 summarizes the various classes of compounds tentatively identified in SPMDs exposed to indoor air. [Pg.171]

Weaver WA, Li J, Wen YL, Johnston J, Blatchley MR, Blatchley ER III (2009) Volatile disinfection by-product analysis from chlorinated indoor swimming pools. Water Res 43 3308-3318... [Pg.134]

If the outdoor level must be estimated also (i.e., historically determined levels are thought to be inadequate), then a larger number of samples are required. For a coefficient of variation equal to 2.5 and a probability of correctly identifying a 10 fold difference of. 95, 10 samples are required indoors and 10 are required outdoors. (Refer to Table IV). To detect a 5 fold increase, a total of 38 samples are required. When both indoor and outdoor levels must be determined, the sampling experiment can be extremely expensive (recall that TEM analysis is approximately 500 per sample). [Pg.202]


See other pages where Indoor analysis is mentioned: [Pg.859]    [Pg.859]    [Pg.315]    [Pg.377]    [Pg.1105]    [Pg.388]    [Pg.1098]    [Pg.133]    [Pg.466]    [Pg.95]    [Pg.26]    [Pg.429]    [Pg.120]    [Pg.67]    [Pg.269]    [Pg.355]    [Pg.1150]    [Pg.113]    [Pg.47]    [Pg.215]    [Pg.235]    [Pg.76]    [Pg.193]    [Pg.194]    [Pg.194]    [Pg.154]   
See also in sourсe #XX -- [ Pg.572 ]




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