U.S. EPA Method 29 Determination of Trace Metals Emissions in Exhaust Gases from Stationary Source Combustion Processes. antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), manganese (Mn), mercury (Hg), nickle (Ni), phosphorous (P), selenium (Se), silver (Ag), thallium (Tl), and zinc (Zn)