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Air Emissions Factors and Quantification

AP 42, Fifth Edition, Volume I Chapter 12: Metallurgical Industry

Chapter 12: Frequent Questions
12.0 Introduction to Metallurgical Industry (1 pg, 10 K)
12.1 Primary Aluminum Production

  • Final Section - October 1998 (PDF) (11 pp, 106 K)
  • Errata - In Table 12.1-2 the number under Prebake Aluminum Cells, Cumulative Emission Factor, Total was corrected to be 5.0 and not 2.5. Also the emissions factors and size distributions in the second and third columns for Prebake Aluminum Cells and HSS Aluminum Cells are fugitive emissions measured at the roof monitor. The emission factor and size distributions in the fourth column for HSS Reduction Cells is for primary emissions. In Table 12.1-3, the Source Classification Codes were added to the table.
  • Background Document (PDF) (42 pp, 162 K)

12.2 Coke Production

12.3 Primary Copper Smelting 

12.4 Ferroalloy Production

12.5 Iron and Steel Production

12.5.1 Minimills

12.6 Primary Lead Smelting

12.7 Zinc Smelting

12.8 Secondary Aluminum Operations

12.9 Secondary Copper Smelting and Alloying

12.10 Gray Iron Foundries

12.11 Secondary Lead Processing

12.12 Secondary Magnesium Smelting

12.13 Steel Foundries

12.14 Secondary Zinc Processing

12.15 Storage Battery Production

12.16 Lead Oxide and Pigment Production

12.17 Miscellaneous Lead Products

12.18 Leadbearing Ore Crushing and Grinding

12.19 Electric Arc Welding

12.20 Electroplating

  • Final Section - Supplement B, July 1996 (PDF) (21 pp, 225 K)
  • Errata - April 2006 - Footnote "a" to Table 12.20-2 in the Electroplating AP-42 section was revised to reflect the correct conversion from grains/hr-ft^2 to mg/hr-m^2. The corrected conversion factor of 697 replaces the value of 0.7 that was in the footnote.
  • Background Document (PDF) (250 pp, 3 MB)

Related Emission Factor Documents

Emission of Fume, Nitrogen Oxides and Noise in Plasma Cutting of Stainless and Mild Steel - Main Document - by Broman B. et al, The Swedish Institute of Production Engineering Research. SELECTED PAGES ONLY., March 1994 (PDF) (6 pp, 400 K)

AP 42 Emissions Factors by Chapter