OSAC Lexicon
The OSAC Lexicon is a compendium of forensic science terms and definitions. This terminology tool was created to help bring consistency and understanding to the way terms are used by the various forensic science. Use of the OSAC Lexicon does not replace the need to reference the original published source.
The terms and definitions in the OSAC Lexicon come from the published literature, including documentary standards and technical reports. It is continually updated with the latest work from OSAC units, as well as terms from newly published documentary standards and standards elevated to the OSAC Registry.
Gradually terms are evaluated and harmonized by the OSAC to a single term. This process results in an OSAC Preferred Term. An OSAC Preferred Term is a term, along with its definition, that has undergone review and evaluation by the FSSB Terminology Task Group and has been approved by the FSSB. The FSSB recommends that subcommittees use OSAC Preferred Terms when drafting standards.
The OSAC Lexicon should be the primary resource for terminology and used when drafting and editing forensic science standards and other OSAC work products.
International Organization for Standardization.
A line on a diagram connecting points of equal char depth.
A class of ignitable liquid characterized in ASTM E1618-11 "Standard Test Method for Ignitable Liquid Residues in Extracts from Fire Debris Samples by Gas Chromatography-Mass Spectrometry" as being comprised almost exclusively of branched chain aliphatic hydrocarbons (isoparaffins).
An ASTM class of petroleum distillate almost exclusively composed of branched alkanes.
Isomers having the same number of each isotopic atom but differing in their positions.
a characteristic of an object in which the refractive index remains constant irrespective of the direction of propagation or vibration of the light through the object.
A characteristic of an object in which the refractive index remains constant irrespective of the direction of propagation or vibration of the light through the object
Acronym for the Information Technology Laboratory of NIST. Seehttp://www.nist.gov/itl/
International Union of Pure and Applied Chemistry. See http://www.iupac.org
JPEG File Interchange Format. See http://www.jpeg.org
A statement that describes a specific job task, lists the items necessary to complete the task, and defines measurable or observable outcomes and evaluation areas for the specific task.
The preferred SI unit of heat, energy, or work. A joule is the heat produced when one ampere is passed through a resistance of one ohm for one second, or it is the work required to move a distance of one meter against a force of one newton. There are 4.184 joules in a calorie, and 1055 joules in a British thermal unit (Btu). A watt is a joule/second. [See also British Thermal Unit (Btu), and Calorie.]
Image compression and storage format specified by the Joint Photographic ExpertsGroup. It is discrete cosine transform-based.
Joint Photographic Experts Group
Image compression and storage format specified by the Joint Photographic ExpertsGroup. It is a wavelet-based method.
Joint Test Access Group
The trained person who undertakes husbandry duties.
A class of sulfur-containing fibrous proteins that forms the foundation of outgrowth tissue from the epidermis, such as hair, nails, feathers, and horns.
a class of sulfur-containing fibrous pro- teins that forms the foundation of outgrowth tissue from the epidermis, such as hair, nails, feathers, and horns.
A verbal or physical action by the canine handler which causes a detector canine to change its actions or to respond to an area or item whether target odor/scent is present or not. (See cueing.)
A measurement of energy release rate.
See ignition temperature.
the energies associated with the transitions of the K, L, and M shell electrons.
Discussion—Each element has characteristic energies of transitions of electrons between shells.
the energies associated with the transitions of the K, L, and M shell electrons.
a structure produced by interlooping one or more ends of yarn or comparable material.
A structure produced by interlooping one or more ends of yarn or comparable material
The level of information, qualifications, and experience needed to perform assigned tasks. DiscussionKnowledge refers to acquired under- standing of the principles and practices related to a particular job, skills refer to acquired analytical and psychomotor behaviors, and abilities refer to the talents, observable behaviors, or acquired dexterity.
The level of information, qualifications, and experience needed to perform assigned tasks
Of established origin or identity associated with a matter of interest
Of established origin associated with the matter under investigation. (E1372)
Discussion - Known soil samples are intentionally collected, typically from crime scene or alibi locations, for comparison to a questioned soil sample. Soils are heterogeneous mixtures of organic matter and minerals that vary with depth and across the landscape. Typically, more known samples are needed to represent the range of variation in soils than are required for manufactured materials.
An item of footwear or a tire of documented origin that is compared to a questioned footwear or tire impression.
An item of footwear or tire from a specific source that is compared to a questioned footwear or tire impression.
In facial identification and image analysis, an image of an individual or object associated with a known or claimed identity or object and recorded electronically or by other medium (also known as exemplars). (Compare questioned image.)
In facial identification and image analysis, an image of an individual or object associated with a known or claimed identity or object and recorded electronically or by other medium (also known as exemplars). (Compare questioned image.)
See test impression.
Biological material for which the identity of the donor is established and used for comparison purposes.
A coating sample of established origin
A coating sample of established origin.
known samples of geological ma- terial are intentionally collected, typically from crime scene or alternate locations, for comparison to a questioned sample. 3.1.7.1 Discussion—Geological materials are typically more heterogeneous than manufactured materials, so a greater num- ber of known samples of geological material are needed to represent the range of variation (see Guide E3272). Reference sample and control sample are synonyms of known sample.
known soil samplesare intentionally collected, typically from crime scene or alternate locations, for comparison to aquestioned soil sample.
A voice signal from an individual who has been identified, or individuated in a waythat allows linking to additional, available information about that individual.
A label placed on the tongue or other inside surface of the footwear that contains information including but not limited to the manufacturer's name, shoe size, country of manufacturer, style number, dating information, barcodes, etc.
Equipment or materials to which has been attached a label, symbol, or other identifying mark of an organization that is acceptable to the authority having jurisdiction and concerned with product evaluation, that maintains periodic inspection of production of labeled equipment or materials, and by whose labeling the manufacturer indicates compliance with appropriate standards or performance in a specified manner.
body that performs one or more of the following activities: testing; calibration; sampling, associated with subsequent testing or calibrationNote 1 to entry: In the context of this document, laboratory activities refer to the three above-mentionedactivities.
The entity providing the analysis, including the staff and the physical facility.
Observation of features which do not allow the examination of certain class or randomly acquired characteristics.
A form made of wood, metal, or synthetic material that approximates the size and shape of a foot. The upper of the footwear is stretched over the last and held in a specific shape and size throughout the manufacturing process. The size on the manufacturer's label is directly related to the size of the last.
Point on a map where the person was last identified or spotted by a witness.
An impression not readily visible to the naked eye.
Learning that takes place unintentionally, and does not manifest in overt behavior at that time, but may become evident at a later stage.