Indoor atmospheres standards

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. 

At the beginning of this book, we presented some discussion of health-based air quality standards. In the final chapter, which follows this one, the scientific bases of control measures for various pollutants are discussed. In between, the complex chemistry that occurs in both polluted and remote atmospheres, and that converts the primary pollutants into a host of secondary species, has been detailed. To provide further perspective on airborne gases and particles and human exposure levels, we briefly treat indoor air pollution in this chapter. As we shall see, for many species it is simply a question of emissions leading to elevated levels indoors. However, there is some chemistry that occurs in indoor atmospheres as well, and it is of interest to compare this to that occurring outdoors. 

D22.05 D6327-98 Standard Test Method for Determination of Radon Decay Product Concentration and Working Level in Indoor Atmospheres by Active Sampling on a Filter... 

J. D. Sinclair, Indoor atmospheres, in Corrosion Tests and Standards Application and Interpretation, 2nd edition, R. Baboian, editor, ASTM International, West Conshohocken, 2005, pp. 349-361. 

The corrosivity of indoor atmospheres must be determined by standard panel exposures. Currently ISO/TC 156 is developing standards on indoor corrosivity classification. These standards have not yet been adopted. 

Time of wetness (TOW), considered as the time during which the corrosion process occurs, is an important parameter to study the atmospheric corrosion of metals. According to ISO-9223 standard, TOW is approximately the time when relative humidity exceeds 80% and temperature is higher than 0°C. No upper limit for temperature is established. In tropical climates, when temperature reaches values over 25°C, evaporation of water plays an important role and the possibility to establish an upper limit respecting temperature should be analyzed. The concept of TOW assumes the presence on the metallic surface of a water layer however, there are recent reports about the formation of water microdrops during the initial periods of atmospheric corrosion, showing that the idea of the presence of thin uniform water layers is not completely in agreement with the real situation in some cases (particularly indoor exposures). 

Ventilation. When plant equipment is located outdoors, there usually is litde need for mechanical ventilation. Many operations must be done indoors, however, and it may be necessary to remove toxic or flammable gases or vapors or process-generated atmospheric heat (53,59). Ventilation and heat-stress standards are intended to avoid hazards associated with high body temperature, heat exhaustion, heat stroke, or discomfort in processes generating high ambient temperatures, eg, glass and steel manufacturing. 

Formaldehyde as a pollutant in the indoor air is usually connected with the use of formaldehyde based resins in e.g. building materials and in furniture. This article presents measurements of the formaldehyde emission from various products containing urea-formaldehyde (UF) or phenol-formaldehyde (PF) resins. The emission from all test objects have been measured in a ventilated test chamber at the standardized testing atmosphere 23 C, 50 % RH according to the International Organization for Standardization (ISO). The emission from woodbased panels and other materials have been measured at a loading factor of 1.0 m /m and at an air change rate of 1.0 h . ... 

A recent standardization project is for Swedish Standard SS 11 72 11 Corrosion Tests in Artificial Atmosphere— Accelerated Outdoor Test. Strom et al. (1992) at Volvo are devising four indoor tests. These developments are still in progress but already show that the 12-month outdoor scab tests can be simulated (in 12 weeks). The outdoor tests show that the distance of blistering of painted coatings from a scribe mark is inversely proportional to zinc coating thickness. Johannson and Rendahl (1991) have evaluated a range of zinc and zinc alloy coatings but find correlation with marine exposure rather low. 

In the case of indoor corrosion, there are several parameters that can be measured to determine the corrosivity of the atmosphere. Unfortunately, there are no standards currently available that relate the corrosivity of the atmosphere to the concentrations of corrosive components, but the measurement of such components may be helpful in determining... 

The quartz crystal microbalance (QCM) is an example of a piezoelectric crystal whose frequency response to mass changes can be used for atmospheric corrosion measurements. In this technique, a metallic corrosion sensor element is bonded to the quartz sample. Mass gains associated with corrosion product buildup induce a decrease in resonance frequency. A characteristic feature of the QCM is exceptional sensitivity to mass changes, with a mass resolution of aroimd 10 ng/cm. The classification of indoor corrosivity, based on the approach of the Instrument Society of America (ISA) S71.01-1985 standard and the use of a copper sensing element and QCM technology, is presented in Table 2.7. 

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