This type of headlight that uses a trace of bromine or iodine vapor is the standard in auto manufacture
... Metal-halide lamps are used in automobile headlights, where they are... [DOC] [TLE] ChT_04014_5 - 76 Nitration spent acid is usually recovered by ... [PAR] SCHOOL University of Melbourne; COURSE TITLE CHEN 20007; TYPE .... to the 
atmosphere Figure 4 ,10 shows a simplied flowchart for a standard SM unit.