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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

Searches term, definition, and source for any of these keywords.
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Searches standard designation number.
Displaying 2251 - 2299 of 2299

Independent examination by one or more examiners to ascertain if a decision, conclusion, or opinion is reproduced or is in conflict with the decision, conclusion, or opinion of another examiner. 

NOTE 1 Verification may be implemented in multiple ways including blind, open, and consensus. The general term verification is inclusive of these various types. 

NOTE 2 Verification is a quality assurance measure for friction ridge examination. 

NOTE 3 The use of the term “independent” indicates an autono

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 142 Best Practice Recommendations for the Resolution of Conflicts in Friction Ridge Examination. AAFS Academy Standards Board, 410 North 21st Street Colorado Springs, CO 80904 , 2022. Source link

The analysis of links, primarily in fraudulent documents.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 921:2017 Guide for Fire and Explosion Investigations. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2017. Source link

Alleles that are not present in the allelic ladder, but have been previously reported or discovered during developmental validation of a particular chemistry. (GeneMapper a ID-X Software and Bin Overlap User Bulletinb,)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 115 Standard for Training in Forensic Short Tandem Repeat Typing Methods using Amplification, DNA Separation, and Allele Detection. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

The association of homologous (i.e., left-right) elements based on similarities in morphology.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 146 Standard for Resolving Commingled Remains in Forensic Anthropology . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2021. Source link

The digital, encoded file primarily containing the sounds of vocalizations of bothspeech and non-speech content, convertible to an acoustic signal replicating the original acoustic signal. A voice data file is extracted from an audio recording, but not all audiorecordings contain voice signals and not all voice data is speech. A physical medium,such as a phonograph record, contains a voice signal but is not a voice data file.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

Use of tonal changes and volume to effectively communicate with the canine.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

spoken message used to guide the user through a dialog with a voice response system

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO/IEC 2382:2015 Information technology — Vocabulary. ISO International Organization for Standardization BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland , 2015. Source link
Reprinted, with permission, from ISO, copyright International Organization for Standardization, 1214 Vernier, Geneva, Switzerland. A copy of the complete standard may be purchased from ISO, https://www.iso.org/store.html

A signal, stored on a digital or analog medium, of vocalizations containing both speechand non-speech content.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

Any audible vocalizations emanating from the human mouth, throat and nasal cavitywith or without speech content.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

An absence of blood in an otherwise continuous bloodstain or bloodstain pattern.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 033, Terms and Definitions in Bloodstain Pattern Analysis Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

The examination of an expert witness in a court proceeding to assist the court in determining whether the expert has the necessary qualifications to testify about the subject-matter.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 154 Standard for Training on Testimony for Forensic Biology . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link

The unit of electrical pressure (electromotive force) represented by the symbol 'E'; the difference in potential required to make a current of one ampere flow through a resistance of one ohm.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 921:2021 Guide for Fire and Explosion Investigations. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2021. Source link

Biological specimen that is typical of its species in accordance with the relevant taxonomic authority. Voucher specimens are of known identity, and are curated with geographic, field collection, and life history data.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 019 Wildlife Forensics General Standards. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Biological specimen that is representative of its species in accordance with the relevant taxonomic authority. Voucher specimens are of known identity, and are curated with available associated geographic, field collection and life history data.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 028 Wildlife Forensics Morphology Standards. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Biological specimen that is representative of its species in accordance with the relevant taxonomic authority and is therefore valid for comparative purposes. Voucher specimens are of known identity, and are curated with available associated geographic, field collection, and life history data.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 180-24 Standard for the Selection and Evaluation of GenBank® Results for Taxonomic Assignment of Wildlife . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link

V-shaped patterns are created by flames, convective or radiated heat from hot fire gases, or smoke within the fire plume. The V pattern often appears as lines of demarcation.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 921:2017 Guide for Fire and Explosion Investigations. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2017. Source link

A process in which a rubber compound is heated under pressure causing a chemical change which transforms the rubber from a soft, tacky substance to tough, hard rubber.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

World Wide Web Consortium. It is an international community that develops standardsfor web development.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

Unit of power, or rate of work, equal to one joule per second, or the rate of work represented by a current of one ampere under the potential of one volt.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 921:2021 Guide for Fire and Explosion Investigations. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2021. Source link

A specific implementation of the RIFF file format for audio data.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
AES 76-2022 AES Standard for Audio Forensics - Speech Collection Guidelines for Speaker Recognition: Interviewing at a Temporary Location. Audio Engineering Society, Inc., 2022. Source link

Waveform Audio File Format.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

Erosion of the surfaces of a footwear outsole or tire tread during use.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

The state of the canine (positive or negative) as a function of his/her ability to cope with its environment (internal or external).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 085 Standard for Detection Canine Selection, Kenneling, and Healthcare. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

The treatment that a canine receives providing for its physical and mental needs.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

A machine used to cut outsoles from unvulcanized calendered outsole material.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Bone that still retains its visco-elastic properties, typically due to retention of soft tissue and associated fluids.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

A clear drafting film, preferably with a minimum thickness of 4 mils, capable of accepting ink, which is used to obtain inked impressions of tires.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

An impression formed under wet conditions including impressions consisting of residues of blood,grease, mud and other wet substances.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 052 Best Practice Recommendation for the Detection and Collection of Footwear and Tire Impression Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2022. Source link

An impression formed under wet conditions including impressions consisting of residues of blood, grease, mud and other wet substances.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

WGS 84 is the World Geodetic System of 1984. At 0000 GMT September 30, 1996 (thestart of GPS Week 873), WGS 84 was redefined and was more closely aligned withInternational Earth Rotation Service (IERS) Terrestrial Reference Frame (ITRF) 94. It isnow formally called WGS 84 (G873). WGS 84 (G873) was adopted as the referenceframe for broadcast orbits on January 29, 1997.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

The distance between the front and rear axles of a vehicle. An approximation of this dimension can be obtained by measuring the distance from the leading edge of the rear tire track to the leading edge of the front tire track on the same side of the vehicle.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Giving birth to a puppy.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 085 Standard for Detection Canine Selection, Kenneling, and Healthcare. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Giving birth to a puppy

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

Equipment used to produce white light (e.g., flash light) to visualize potential items of evidence.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 049 Best Practice Recommendation for Lifting of Footwear and Tire Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

Distractor odors that are naturally occurring in the search environment that are not placed by evaluators, observers or participants. Animal remains that were not placed by someone, holes that were dug by wild animals, feces from other animals, etc. (See natural distractors.)

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

To locate target odor/scent sources in a rural environment.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

There are several proprietary formats developed by Microsoft. Windows Media Video(WMV) was developed for Internet streaming applications. Windows Media Audio(WMA) has four distinct codecs: WMA Pro, WMA Lossless, WMA Voice and theoriginal codec also referred to as WMA. The Advanced Systems Format (.asf) is acontainer format designed for streaming media. The Advanced Stream Redirector(ASX) is a type of XML designed to store a playlist for a multimedia presentation.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

A computer system that uses dental and anthropometric characteristics to rank possiblematches for missing persons and unidentified human remains.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

An altered stain resulting from an object moving through a preexisting wet bloodstain.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 033, Terms and Definitions in Bloodstain Pattern Analysis Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link

Revocation or cancellation of a statement of conformity.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO/IEC 17000:2014 Conformity assessment -- Vocabulary and general principles. International Organization for Standardization/International Electrotechnical Commission, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2014. Source link
Reprinted, with permission, from ISO, copyright International Organization for Standardization, 1214 Vernier, Geneva, Switzerland. A copy of the complete standard may be purchased from ISO, https://www.iso.org/store.html

Windows Media Audio. This refers to both a Microsoft proprietary audio file format and the audio codecs it uses.WMA can use either lossy or lossless codecs.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
AES 76-2022 AES Standard for Audio Forensics - Speech Collection Guidelines for Speaker Recognition: Interviewing at a Temporary Location. Audio Engineering Society, Inc., 2022. Source link

An outline of the tasks to be completed as part of the investigation including the order or timeline for completion. Planning the Investigation.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 921:2021 Guide for Fire and Explosion Investigations. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2021. Source link

The range of concentration that can be adequately determined by an instrument, where the instrument provides a useful signal that can be related to the concentration of the analyte

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 036 Standard Practices for Method Validation in Forensic Toxicology. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

Acronym for Wavelet Scalar Quantization, a compression algorithm used for 500 ppifriction ridge prints.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

Extensible Markup Language. A convention for marking up and tagging data forelectronic transmission. An XML package is built from text content marked up with texttags such as . In XML one can create as many tags as needed.These tags describe the type of content they contain rather than formatting or layoutinformation. The types of tags allowed in an XML file are typically defined andconstrained by a specification such as an XML Schema Definition (XSD).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

An XML schema declares the XML elements, their structure and order. A schemaassigns data types, names, and attributes to the elements. A schema may be used tovalidate the structure and content of an XML package.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link

X3P is an open file format for the exchange of three dimensional surface topography data instandard units. Details are specified in ISO 25178-72.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 062 Standard for Topography Comparison Software for Toolmark Analysis. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Short tandem repeat markers found on the Y-chromosome that enable male-specific DNA testing and can be useful in cases involving sexual assault; variations in Y-STRs may be used for distinguishing individuals, and in biological relationship and ancestry testing.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 022 Standard for Forensic DNA Analysis Training Programs. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

A disease communicable from vertebrate animals to humans.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link