Analytical procedures for the measurement of unregulated emissions in automotive exhaust have been developed. Compounds in the emissions characterization inventory include organic sulfides, nickel carbonyl, aldehydes, ammonia, sulfur dioxide, hydrogen sulfide, organic amines, nitrous oxide, individual hydrocarbons, total cyanide, sulfate, phenol, particulate and others.
Validation experiments were conducted with selected methods to develop a well-defined analytical procedure. Qualification of the procedure involved injection of known amounts of the individual species into a dilution tunnel - CVS system. These analytical procedures are currently being employed to characterize unregulated emissions from a variety of low NOx vehicles, advanced powerplants and vehicles operating under malfunction conditions.