Dust, general

Nuisance Dust Generally refers to innocuous dust, not recognized as the direct cause of a serious pathological condition. 

The neutral solution is purified to remove impurities more noble than zinc, e g., cadmium, copper, cobalt, nickel, arsenic, antimony, and germanium. The purification is accomplished by cementation in two or more steps with the addition of zinc dust. Generally, at least one cementation step is conducted at high temperature with arsenic, antimony, or copper-arsenic added. Cadmium is usually recovered in the metallic state and copper, nickel, and cobalt are recovered as sludges if present in sufficient quantities. 

Very good Potential affect (high temperatures, dust) Generally performed by manufacturer Typically a 40-h course Typically annual Daily to weekly Electronics, materials and computer science, analytical chemistry Electronics/mechanical... 

Synthesis of A -Fmoc Amino Adds with Fmoc-Cl (17) in the Presence of Zn Dust General Proce-dure I ° ... 

Average industrial dust, general foundry dust Sawdust, grinding dust, limestone dust 3500 000... 

Folpet appears as colorless crystals. It is sold as powders and dusts. Generally, Folpet is available as an industrial biocide (Federal Register August 25, 2004). 

Summary data (Table 11.1) suggest that worldwide geometric mean concentrations of Pb in house dust generally vary between 80 and 1007 ig g while Cd concentrations fall within a tighter range (4.2 to 7.7 Jg g ), as do Cu concentrations (121 to 311 jg g ). An exception is the German survey by Sei-... 

Dust-explosion control is more difficult to evaluate, as it depends on the particle size, hygro opicity, surface, and combustibility of the dust. The lower explosive limit of air-borne dust generally ranges from 0.01 to 0.5 oz/ft of air. More detailed information is available from the NFPA. 

A safe premise is to consider all dust as nuisance and take due precautions. The type of dust is important and the crucial variety is respirable dust, generally considered to be about 3.5-5.0 pm in size and capable of reaching the alveoli of the lung without being trapped in nasal hair, or trapped enroute on the walls of the trachea or bronchia. Particles 7-10 pm in size will not reach the lung and are not considered respirable. 

Influence of Thickness of Oil Layer on Adhesion. Atmospheric dust generally contains not only solid particles, but also oily contaminants, which settle on surfaces and make the surfaces oily. Also, the surfaces of some objects such as motor vehicles may become oily in the operating process. It has been found that 17% of the adherent particles on the surfaces of motor vehicles operating in Moscow do have such a layer of oil. Roughly the same results were obtained in an analysis reported in [234] on the contaminants appearing on exterior surfaces of railroad rolling stock. On a locomotive, for example, 23% of the adherent particles were in contact with oily surfaces, and on the railroad cars the figure was 19%. The presence of oily contaminants on surfaces tends to increase particle adhesion because of tackiness this is illustrated by data shown in Table VIII.8 [11]. 

Relative to exterior leaded dusts, household and other interior dust lead reservoirs pose a higher lead exposure risk to vulnerable human populations such as young children. More so than roadside or other exterior leaded dusts, interior dusts generally reflect more lead source inputs, the relative size of... 

The first explosion is known as primary causing a rupture of the vessel releasing the flammable gas/ air mixture into the atmosphere. With dust generally suspended in the air around the process equipment or dust lying undisturbed within the building a secondary explosion occurs. 

Byssinosis is a bronchopathy due to inhalation of cotton dust, generally considered as an occupational asthma, although the immunological mechanism is still discussed. Respiratory syndrome induced by inhalation of nylon dust (Flock worker s lung) is considered different from HP (Kern et al. 2000). Metal fume fever following inhalation of metal fumes (zinc, copper) is an influenza-like reaction with poor respiratory symptoms different from HP. 

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