Podcast
Questions and Answers
Which of the following materials is NOT listed as a type that trace evidence examiners analyze?
Which of the following materials is NOT listed as a type that trace evidence examiners analyze?
What is one purpose of the examinations conducted by trace evidence examiners?
What is one purpose of the examinations conducted by trace evidence examiners?
Which of the following is included in the list of materials that may be analyzed for trace evidence?
Which of the following is included in the list of materials that may be analyzed for trace evidence?
Which chemical category is listed among those analyzed in trace evidence?
Which chemical category is listed among those analyzed in trace evidence?
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What type of comparison might trace evidence examinations entail?
What type of comparison might trace evidence examinations entail?
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Which of the following is an example of a wax material that may be examined?
Which of the following is an example of a wax material that may be examined?
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What type of material related to fire suppression may be analyzed in trace evidence?
What type of material related to fire suppression may be analyzed in trace evidence?
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Which of the following lubricating substances is analyzed in trace evidence?
Which of the following lubricating substances is analyzed in trace evidence?
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What is the recommended method for packaging inhalants?
What is the recommended method for packaging inhalants?
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How should adhesive tape on a roll be packaged for a fracture match exam?
How should adhesive tape on a roll be packaged for a fracture match exam?
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What should be done if loose tape is cut from a victim?
What should be done if loose tape is cut from a victim?
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How should dry unknown powders be collected for evidence?
How should dry unknown powders be collected for evidence?
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What is crucial to remember when handling adhesive tape evidence?
What is crucial to remember when handling adhesive tape evidence?
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What is the proper action if a powder is damp or moist?
What is the proper action if a powder is damp or moist?
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Which of the following statements about fracture match exams is true?
Which of the following statements about fracture match exams is true?
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How should wads of tape be packaged to preserve evidence?
How should wads of tape be packaged to preserve evidence?
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What is the appropriate packaging for powders when volatiles are suspected?
What is the appropriate packaging for powders when volatiles are suspected?
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In case of suspected bank dye packs, what is the correct way to package the expended packs?
In case of suspected bank dye packs, what is the correct way to package the expended packs?
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Which statement about packaging and handling unknown materials is true?
Which statement about packaging and handling unknown materials is true?
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What type of samples should be submitted if a known source is present?
What type of samples should be submitted if a known source is present?
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What is the recommended action if liquid evidence is discovered?
What is the recommended action if liquid evidence is discovered?
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How should solids, like sugar or salt, found in a gas tank be collected?
How should solids, like sugar or salt, found in a gas tank be collected?
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What should be done with materials that are volatile?
What should be done with materials that are volatile?
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What is the appropriate response if a material is suspected to be an acid or a base?
What is the appropriate response if a material is suspected to be an acid or a base?
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What type of information should an investigator document about a questioned sample?
What type of information should an investigator document about a questioned sample?
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When handling acids or bases, what is the recommended packaging material?
When handling acids or bases, what is the recommended packaging material?
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If a victim ingests a substance, what aspect should be documented by the investigator?
If a victim ingests a substance, what aspect should be documented by the investigator?
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Which method is appropriate for collecting residues from skin after exposure to pepper spray?
Which method is appropriate for collecting residues from skin after exposure to pepper spray?
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How should clothing analyzed for the presence of pepper spray be packaged?
How should clothing analyzed for the presence of pepper spray be packaged?
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What should be done if a sample of a household product is needed for analysis?
What should be done if a sample of a household product is needed for analysis?
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For items like pepper spray, what is the preferred type of container if latent print processing is required?
For items like pepper spray, what is the preferred type of container if latent print processing is required?
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What kind of chemical types can be identified through forensic investigation?
What kind of chemical types can be identified through forensic investigation?
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Study Notes
General Chemical Overview
- Trace Evidence examiners analyze various materials including acids/bases, automotive fluids, inks, dyes, glues, and tapes
- Examinations can identify questioned substances or compare them to known samples to determine origins.
- Important information:
- Location of recovered substance
- Substance's original condition
- Application method (brushed, poured, sprayed)
- Substance properties (odor, burn, texture)
- Victim injury details (if applicable)
- Ingestion effects (if applicable)
- Medical treatment received (if applicable)
Evidence Handling and Submission
-
Acids and Bases (Alkalis/Caustics):
- No larger than one pint in their original container if not leaking.
- Sample with no more than one ounce in a plastic bottle or jar with non-metal lid.
- Package in a non-metal container with packing material.
- Use extreme caution, package with proper plastic containers and avoid metal contact.
-
Pepper Spray/Tear Gas:
- Canister in plastic bag unless latent prints are needed, then use cardboard box.
- Clothing in paper bag.
- Tear gas clothing in clean, unused, lined metal paint can.
- Gauze squares moistened with isopropyl alcohol can collect residues from skin.
- Submit a control gauze square.
- Separate container for questioned and known samples.
-
Inhalants (e.g., glue sniffing, huffing):
- Place questioned sample in a clean, unused, lined metal paint can.
- Submit known containers/sources for comparison.
- Original containers in plastic or paper bags.
- Inhalants are volatile materials that evaporate readily, so airtight containers like metal paint cans are crucial.
-
Adhesive Tapes:
- If a fracture match is desired, tape ends must be protected.
- Package in plastic bag or container unless latent prints are needed, then use cardboard box.
- Do not mark, warp, or distort tape. Mark cut ends if tape needs to be cut.
- If tape is flat with exposed adhesive, press it onto a heavy plastic bag or sheet.
- Place in envelope or paper bag.
- Wads of tape can be placed in a clean, unused, lined metal paint can or plastic container.
- Handle tape minimally to avoid contamination.
-
Unknown Powders/Liquids/Solids:
- Dry powder in a paper evidence fold.
- Damp powder in paper fold after drying, unless volatiles are suspected, then use a clean, unused, lined metal paint can.
- Plastic containers/vials are acceptable for powders.
- Liquid in plastic or glass container.
- Submit known sources for comparison.
- Sugar/salt in a gas tank: collect crystals near fill spout in a paper fold. Collect solids/liquid in the bottom of a removed gas tank in a glass jar or plastic container.
- Fuel/oil filter may also be collected for testing.
- Handle unknown materials with extreme caution and contact Division of Consolidated Laboratory Services for suspected biological or chemical agents.
-
Bank Dye Packs or Articles with Bank Dye:
- Expended dye packs in a plastic bag, then in paper bag.
- Wrap clothing suspected of containing dye in paper, then place in a paper bag.
Submission Reminders
- Use common sense when packaging.
- Protect evidence from loss, contamination, or change.
- Refrigerate degradable materials.
- Place volatile materials in clean, unused, lined metal paint cans.
- Do not package acids or bases in metal or allow them to contact metal.
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Description
This quiz covers the analysis of various materials, including acids, bases, and trace evidence. It focuses on the methods of examination, key considerations for substance properties, and protocols for evidence handling and submission. Test your knowledge on the critical aspects of chemical analysis in forensic contexts.
