Metals aerosols

Potential hazards associated with electron beam vacuum melting of metals include the possibility of ignition of metal aerosols or condensate films in the event of sudden loss of vacuum at elevated temperatures. 

Zimmerman, N. Drehmel, D.C. Abbott, J.H. "Characterization and Generation of Metal Aerosols" U.S. Environmental Protection Agency Report No. EPA-600/7-78-013 February, 1978. 

Park K, Cho G, Kwak J-h (2009) Development of an aerosol focusing-laser induced breakdown spectroscopy (aerosol focusing-LIBS) for determination of line and ultrafine metal aerosols. Aerosol Sci Technol 43 375-386... 

Bisgaard, H. A metal aerosol holding chamber devised for... 

Weissman SH, Cuddihy RG, Medinsky MA. 1983. Absorption, distribution, and retention of inhaled selenious acid and selenium metal aerosols in beagle dogs. Toxicol Appl Pharmacol 67 331-337. 

It is in the field of aerosols that metal containers have predominantly established themselves. Although glass, plastic and plastic-coated glass aerosols are finding their own specialised applications, metal aerosols are likely to retain the bulk of the market as long as cost advantages are offered. 

Crimping—shaping, folding and crimping, e.g. collapsible tubes (metal). Aerosol valves for glass bottles. Overseals for injection vials. 

Metallic aerosols can be made by passing a massive amount of electricity through a thin wire by discharging a bank of capacitors, whereupon the wire explodes." The technique, to which the name deflagration has been applied, was pioneered (as were so many things) by Michael Faraday," who converted a gold wire into powder by using the current produced by a Leiden battery. 

As a first cut, LIBS has been applied to a metal aerosol in open air. A diagram of the apparatus is shown in Figure 9. Flowing the gas throu a container of material generates a particle-laden stream. This stream is then diluted, reducing the particle concentration to ensure only one particle in the measuring volume. Commercially supplied 20-40 pm aluminum or magnesium particles were studied. Both of these materials have a layer of oxide as diey were exposed to air. Typical LIBS spectrums from these materials are shown in... 

Lim) often cause the greatest alteration in pulmonary function because they can penetrate farther into the alveoli, whereas the larger particles are deposited in the upper respiratory tract. Increase in airway resistance at high acid concentrations has been demonstrated by several authors. Presence of ammonia in expired air has been reported to afford some protection in humans Synergism has been demonstrated when sulfuric acid is deposited on zinc oxide dusts in the presence of sulfur dioxide, and also when combined with nitrogen dioxide or sulfur dioxide, ozone, metallic aerosols, and sulfuric acid. 

In principle, tellurium deposition on stainless steel in the primary system would largely prevent this element from being released to the containment. However, tellurium vapor could react chemically with a variety of metallic aerosols to form tellurides in particular it has a high affinity for silver and cadmium, as well as for tin volatilized from the Zircaloy claddings. Thus, tellurium transport through the primary system would be primarily controlled by aerosol transport characteristics. Spence and Wright (1987) have calculated that inclusion of these processes of depo-... 

Furrer, M., Cripps, R. Validation of Impair 2 code using ACE test results from the Radioiodine Test Facility (RTF). Proc. 3. CSNI Workshop on Iodine Chemistry in Reactor Safety, Tokai-mura, Japan, 1991 Report JAERI-M 92-012 (1992), p. 329-344 Furrer, M., Gloor, T. Effects of P , y radiolysis on cesium iodide solutions in contact with simulated silver metal aerosol. Proc. Specialists Workshop on Iodine Chemistry in Reactor Safety, Harwell, England, 1985 Report AERE R 11974 (1986), p. 193-199 Gauvain, J., et al. Iode 2.0 User manual. Report SEAC/91/04 (1991)... 

Virtual impactors have been designed to eliminate problems of bounce and re-entrainment and to allow the collection of larger particles (Chen et al., 1986 Marple and Chein, 1980). In a virtual impactor, the intake air is typically divided into two air streams the major and the minor flows. The major flow carries most of the fine particles smaller than the cutoff diameter and the minor flow carries all the coarse particles above the cutoff diameter with a small fraction of the fine particles. Various studies on virtual impactors have been carried out for particle collection and concentration since the late 1980s. Meyer and Lee (1994) used a virtual impactor as a means of concentrating metal aerosol suspended in the air to enhance the performance of an inductively coupled plasma analyser. Kim et al. (2000) designed and tested multi-nozzle virtual impactors for high-volume particle collection. Virtual impactors, however, have an inherent problem that a small fraction of the fine particles is collected with the large particles. 

Methods of testing metal aerosol dispensers 1229/1997 GS918... 

Workers in mines and smelters can be exposed to a wide range of metal aerosols, including metals that are only present in trace amounts (168). For example, ead-mium is a by-product of zinc and lead mining and smelting, with workplace concentrations generally 0.05 p,g/m or less (168). The ACGIH TLV for eadmium... 

---