Vehicle volatility requirements

Vehicle volatility requirements are a strong function of ambient temperatures. ASTM has defined five volatility classes based on expected minimum and maximum daily temperatures. These classes and their ranges are shown in Table 3. Each month, each state is assigned a volatility class, depending on its temperature history. Table 3 also shows the ASTM volatility specifications for each class. 

Tests on vehicles have shown that the volatility index as defined expresses satisfactorily the fuel contribution during hot operation of the engine (Le Breton, 1984). In France, specifications stipulate that its value be limited to 900, 1000 and 1150, respectively, according to the season (summer, spring/fall, winter). The automobile manufacturers, being even more demanding, require in their own specifications that the FVI not be exceeded by 850 in summer. 

Because nonattainment areas still exist, especially in urban areas, the 1990 CAAA contain new and more stringent requirements for such areas. The ambient air quality standards for ozone are of particular concern. Controls include tighter standards on emissions from motor vehicles, use of cleaner fuels, and additional controls on industrial facilities. One of the biggest impacts on the chemical industry is more stringent requirements for minimizing the emission of volatile organic compounds (VOCs). This can include process emissions as well as emissions from storage tanks. 

Worldwide, new environment legislation has set product specifications for fuels. Table 18.4 lists the quality standards for automotive gasoline and diesel.10 These mandates are geared to lower tailpipe emission from vehicles. Sulfur content and volatility will be strictly limited in future fuel requirements. 

Coating vehicle usually identifies a combination of binder and volatile liquid. It may be a solution or a dispersion of fine binder particles in a nonsolvent formulation. No pigments are included if a clear, transparent coating is required. The composition of the volatile liquid provides enough viscosity for packaging and other application, but the liquid itself rarely becomes part of the finished coating. 

It is important to note that in none of these examples of intermolecularily stabilized barium bis( -diketonate) complexes was found complete achievement of the criteria for CVD precursors for SMO given at the outset of this section. Therefore, other routes had to be explored in the search for the required higher volatility, higher stabihty vapor transport vehicles to be employed for the heavy group 2 elements desired for electronic materials applications. 

Hazard Class 6 materials are poisons that are solids and liqnids. Some of the hqnids are volatile and produce vapors, which are an inhalation hazard. Volatile poisons that are an inhalation hazard require the transport vehicle to be placarded regardless of the quantity. Class 6 is divided into two subclasses 6.1 and 6.2. The DOT defines a Class 6.1 poison as a material, other than a gas, known to be so toxic to humans as to afford a health hazard during transportation or which, in the absence of adequate data, is presumed to be toxic to humans because it falls within any one of the following categories when tested on laboratory animals. 

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