Quimica

U.S. Department of Justice Federal Bureau of Investigation Laboratory Division

Processing Guide for Developing Latent Prints

Revised 2000

Processing Guide for Developing Latent Prints (2000)
Compiled by: Timothy A. Trozzi Fingerprint Specialist (Forensic Examiner) Federal Bureau of Investigation Rebecca L. Schwartz Research Chemist Federal Bureau of Investigation Mitchell L.Hollars Fingerprint Specialist (Forensic Examiner) Federal Bureau of Investigation Edited by: Lallie D. Leighton Sally A. Schehl Yvette E. Trozzi Colleen Wade Questions concerning the Processing Guide for Developing Latent Prints may be directed to: Latent Print Unit Room 10861 Federal Bureau of Investigation 935 Pennsylvania Avenue NW Washington, DC 20535-0001 (202) 324-2163 FAX (202) 324-1109E-mail: reschwar@leo.gov

Processing Guide for Developing Latent Prints (2000)

Table of Contents
Introduction .............................................................................................................................................. 1 Safety........................................................................................................................................................ 2 Laboratory Chemicals and Equipment .................................................................................................. 2 Weights, Measures, and Temperature .................................................................................................... 3 Processing Procedures and Sequences................................................................................................ 4 Standard Processes Adhesive Surface Techniques Alternate Black Powder .................................................................................................. 10 Ash Gray Powder ............................................................................................................ 11 Gentian Violet................................................................................................................. 12 Sticky-Side Powder ......................................................................................................... 13 Amido Black (Methanol Base) ..................................................................................................... 14 Amido Black (Water Base — Fischer 98).................................................................................... 16 Cyanoacrylate Fuming (Microburst Method) ................................................................................ 18 Cyanoacrylate Fluorescent Dye (RAM) ....................................................................................... 19 DAB (Diaminobenzidine).............................................................................................................. 21 DFO (1,8-Diazafluoren-9-One) .................................................................................................... 24 Fingerprint Powders .................................................................................................................... 26 Iodine Fuming.............................................................................................................................. 28 Iodine Spray Reagent .................................................................................................................. 29 LCV (Leucocrystal Violet) ............................................................................................................ 31 Ninhydrin (Petroleum Ether Base)............................................................................................... 33 Physical Developer (PD) .............................................................................................................. 34 Silver Nitrate ................................................................................................................................ 38 Sudan Black...