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personnel, or erfie bomb technicians. Special packaging is required, and the amount to be shipped is regulated. An FD-861 form (Mail/Package Alert) is required for shipping bomb components to the FBI Laboratory.
    Explosives Residue Examinations
    Instrumental analyses of explosives residue can determine whether substances are high-explosive, low-explosive, or incendiary mixtures; whether the composition of the substances is consistent with known explosives products; and the type of explosives. Explosives residue can be deposited on metal, plastic, wood, paper, glass, cloth, and other surfaces. Residue may be deposited after handling, storing, or initiating an explosive.
    Questions concerning explosives residue evidence should be directed to 703-632-7626. Follow the evidence submission directions, including Requesting Evidence Examinations and Packaging and Shipping Evidence .
Some explosives residue is water-soluble and must be protected from moisture. Other residue evaporates quickly and must be collected as soon as possible in airtight containers such as metal cans, glass jars, or heat-sealed or resealable nylon or Mylar bags. Ziplock storage bags are not suitable for shipping or storing explosives residue evidence. Do not fill the containers to the top. Pack to prevent breakage.
Collect and preserve control samples from the blast site.
Extreme care must be taken to avoid contaminating explosives residue evidence .
Never store or ship explosives residue evidence with bulk explosive materials.
    Never store or ship explosives residue evidence from a crime scene with evidence from a search site.
    FBI Disaster Squad
Assists in printing the deceased at disaster scenes.
Assists in collecting antemortem fingerprints of victims.
Assists in identifying friction ridge skin of the deceased.
Deployment of the FBI’s Disaster Squad requires consent from the disaster scene coroner or medical examiner, a ranking law enforcement or government official, a representative of the National Transportation Safety Board, or a representative of the U.S. Department of State.
Requests for assistance must be made through the nearest FBI field office or the FBI’s Strategic Information and Operations Center at 202-323-3300 .
    Feather Examinations
    Feather examinations can determine bird species and can compare feathers found on clothing, vehicles, and other objects with feathers from the crime scene.
    Questions concerning feather evidence should be directed to 703-632-8449. Follow the evidence submission directions, including Requesting Evidence Examinations and Packaging and Shipping Evidence .
Submit feathers in heat-sealed or resealable plastic bags or paper bags.
    Firearm Examinations
    Firearms
    Firearm examinations can determine the general condition of a firearm and whether the firearm is mechanically functional or in a condition that could contribute to an unintentional discharge. Triggerpull examinations can determine the amount of pressure necessary to release the hammer or firing pin of a firearm. Examinations can determine whether a firearm was altered to fire in the fullautomatic mode. Obliterated and/or altered firearm serial numbers sometimes can be restored. Firearms can be test-fired to obtain known specimens for comparison with evidence ammunition components, such as bullets, cartridge cases, and shotshell casings.
    Comparisons of suspect firearms can be made with firearms depicted in surveillance images, possibly resulting in an “association” conclusion. Photogrammetry can determine the length of the weapon(s) used by the subject(s) depicted in the surveillance images. See Image Analysis Examinations .
    Bullets
    Fired bullets can be examined to determine general rifling characteristics such as caliber, physical features of the rifling impressions, and the manufacturer of the bullets. The microscopic characteristics on evidence bullets can be compared with test-fired bullets from a suspect firearm to determine whether the evidence