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.
An opening in an optical system that controls the amount of light passing through a system.
request by the provider of the item of inspection to the inspection body for reconsideration by that body of adecision it has made relating to that itemNOTE Adapted from ISO/IEC 17000:2004, definition 6.4.
Request by the provider of the item of inspection to the inspection body for reconsideration by that body of a decision it has made relating to that item
A request by a forensic science service provider to the inspection body for reconsideration by that body of a decision, finding, or other action.
This refers to devices that have successfully completed a test of fingerprint capturedevices that is performed in accordance with procedures established by the FBI inEBTS Appendix F. [2013a>] See https://www.fbibiospecs.cjis.gov for Appendix F,CJIS Image Quality Specifications. [
A relationship where an individual works for an entity while learning skills.
Permission for a product or process to be marketed or used for stated purposes or under stated conditions. Approval can be based on fulfillment of specified requirements or completion of specified procedures.
Acceptable to the authority having jurisdiction
Acceptable to the authority having jurisdiction
See shaping.
A high-temperature luminous electric discharge across a gap or through a medium such as charred insulation.
Identifying and documenting a fire pattern derived from the identification of arc sites used to aid in determining the area of fire origin or spread.
Melting of conductors and conducting surfaces as a result of electrical arcing. The characteristics of arc melting are described in 9.11.1.1.
The location on a conductor with localized damage that resulted from an electrical arc.
In computer forensics,a bit stream dupli- cate of data placed on media that is suitable for long-term storage.
Arcing associated with a matrix of charred material (e.g., charred conductor insulation) that acts as a semiconductive medium.
The space in two dimensions to which the directionalities of spatter stains can be retraced to determine the location of the spatter producing event.
A structure, part of a structure, or general geographic location within a fire scene, in which the 'point of origin' of a fire or explosion is reasonably believed to be located. (See also 3.3.149, Point of Origin.)
The space in three dimensions to which the trajectories of spatter can be utilized to determine the location of the spatter producing event.
The act of using a canine to search a designated area for a target odor/scent.
Surface measurement method that produces a topographical image of a surface, which may berepresented mathematically as a height function z (x, y) of two independent variables (x, y).
A major group of unsaturated cyclic hydrocarbons containing one or more rings, typified by benzene, which has a 6-carbon ring containing nominally three double bonds. [In fire debris, this term is typically used to refer to alkylbenzenes, which are benzene rings with aliphatic substitutions.]
A class of ignitable liquid characterized as being comprised almost exclusively of aromatic or condensed ring aromatic compounds, or both. Some examples of commercial products that may be in this class are: paint and varnish removers, insecticide carriers, auto parts cleaners and some specialty products.
a sharp line on the fracture surface defining the crack front shape of an arrested or momentarily-hesitated crack.
A condition in which the heart beats with an irregular or abnormal rhythm
A condition in which the heart beats with an irregular or abnormal rhythm.
A fire pattern displayed on the cross-section of a burned wooden structural member.
The crime of maliciously and intentionally, or recklessly, starting a fire or causing an explosion.
(1) A particular item or object, typically one of a specified type used to present to the canine for scent discrimination. (2) Scented objects left on the track or in a search area at various intervals to which the canine is expected to indicate.
(1) A particular item or object, typically one of a specified type used to present to the canine for scent discrimination.(2) Scented objects left on the track or in a search area at various intervals to which the canine is expected to indicate.
(1) A particular item or object, typically one of a specified type used to present to the canine for scent discrimination.(2) Scented objects left on the track or in a search area at various intervals to which the canine is expected to indicate.
(1) A particular item or object, typically one of a specified type used to present to the canine for scent discrimination.(2) Scented objects left on the track or in a search area at various intervals to which the canine is expected to indicate.
The process of locating and indicating items that contain non-specific or targeted human scent. (See evidence search.)
A by-product, artificial feature, or change resulting from human activity or a technical process. (Compare noise.) DISCUSSION: Examples include speckles in a scanned picture, 'blocking' in compressed images, distortion in over-saturated audio, and the automatic creation of temporary files due to normal usage of a computer.
Visual/aural aberration in an image, video, or audio recording resulting from a technical or operational limitation. DiscussionExamples include speckles in a scanned picture or blocking in images compressed using the JPEG standard.
A non-allelic product of the amplification process (e.g., stutter, non-templated nucleotide addition, or other non-specific product), an anomaly of the detection process (e.g., pull-up or spike), or a byproduct of primer synthesis (e.g., 'dye blob') that may be observed on an electropherogram; some artifacts may complicate the interpretation of DNA profiles when they cannot be distinguished from the actual allele(s) from a particular sample.
Distractions placed in the search area that do not occur naturally. (i.e., Proofing items such as containers, gloves that are not contaminated with human remains, uncontaminated storage containers etc.)
The American National Standard Code for Information Interchange.
The American Association of Crime Lab Directors.
The proportion of the tire's height to its width.
The width-to-height ratio of a pixel or the captured image.
The ratio of the width to the height of a rectangle, such as an image, a pixel, or an active video frame
A record of the assessments of the canine team, i.e., evaluations during either the training or certification to access the canine team's ability and proficiency. The assessment records may be combined with training and certification records or maintained separately. A record documenting the performance of the canine team, especially an account of an act or occurrence kept in writing or some other permanent form, i.e., digital format, which is discoverable.
A record of the assessments of the canine team, i.e., evaluations during either the training or certification to access the canine team's ability and proficiency. The assessment records may be combined with training and certification records or maintained separately. A record documenting the performance of the canine team, especially an account of an act or occurrence kept in writing or some other permanent form, i.e., digital format, which is discoverable.
A record of the assessments of the canine team, i.e., evaluations during either the training or certification to access the canine teams ability and proficiency. The assessment records may be combined with training and certification records or maintained separately. A record documenting the performance of the canine team, especially an account of an act or occurrence kept in writing or some other permanent form, i.e., digital format, which is discoverable.
A record of the assessments of the canine team, i.e., evaluations during either the training or certification to access the canine teams ability and proficiency. The assessment records may be combined with training and certification records or maintained separately. A record documenting the performance of the canine team, especially an account of an act or occurrence kept in writing or some other permanent form, i.e., digital format, which is discoverable.
An evaluation during training and/or certification process; a tool to assess canine team ability.
An evaluation during training and/or certification process; a tool to assess canine team ability.
An evaluation during training and/or certification process; a tool to assess canine team ability.
An evaluation during training and/or certification process; a tool to assess canine team ability.