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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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Displaying 1751 - 1800 of 3438

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.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO/IEC 17025:2017 General Requirements For The Competence Of Testing And Calibration Laboratories. International Organization for Standardization/International Electrotechnical Commission, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2017. 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

The entity providing the analysis, including the staff and the physical facility.

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

Observation of features which do not allow the examination of certain class or randomly acquired characteristics.
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

Process of stamp manufacturing using “laserable rubber” (pre-vulcanized natural rubber) and laser engraving to cut the image to form the die of the stamp.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 117 Standard for Examination of Stamping Devices and Stamp Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2020. Source link

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.
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

Point on a map where the person was last identified or spotted by a witness.

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

An impression not readily visible to the naked eye.
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

Learning that takes place unintentionally, and does not manifest in overt behavior at that time, but may become evident at a later stage.

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

An impression or image of friction ridge skin left on a surface.

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 public employee whose duties primarily involve the enforcement or investigation of alleged or suspected violations of law.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 160 Best Practice Recommendation for Initial Response at Scenes by Law Enforcement Officers. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904 , 2024. Source link

The systematic process of removing debris from the top down and observing the relative location of artifacts at the fire scene.

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

ammunition incorporating a primer that does not contain lead.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

A period in which early progress in learning appears to have stopped and improvement is at a standstill. The plateau is followed by a new period of progress.

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

Indicates that the transaction element was valid in previous versions of the standard.Systems claiming conformance to this version of the standard shall only use the elementwhen transmitting information stored prior to the adoption of this version of the standard.

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

This characterizes the dispersion of values used for measuring dental age assessment based on the variation within the data.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ADA 1077-2020 Human Age Assessment by Dental Analysis. American Dental Association (ADA), 211 East Chicago Ave., Chicago, IL, 60611, 2020. Source link

in facial identification, a verbal or numeric scale that indicates the level of confidence regarding identification or exclusion of a subject.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

A product of an EDD examination. The developed toner image on the imaging film is preserved by applying fixing film to create a lift.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 044 Standard for Examination of Documents for Indentations. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

An adhesive or other medium used to capture and preserve an impression.
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 adhesive or other medium used to capture and preserve an impression.

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

Use of a xenon flash in the manufacturing of a flat die stamp. Numerous light bursts are used to seal the background of the stamp pad leaving open micropores in the area of the flat die to print the text.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 117 Standard for Examination of Stamping Devices and Stamp Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2020. Source link

a microscope that employs light in the visible portion of the electromagnetic spectrum.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

in facial identification, an automated conclusion based upon threshold scores with no human involvement.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

the majority non-carbohydrate portion of wood; it is an amorphous polymeric substance that cements cellulosic fibers together and is the principal constituent of woody cell walls.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

The probability of the evidence under one proposition (hypothesis), divided by the probability of the evidence under an alternative, mutually exclusive proposition (hypothesis). The magnitude of its value expresses the weight of the evidence.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 046 Wildlife Forensics Validation Standards—STR Analysis. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2019. Source link

An estimate of the lowest concentration of an analyte in a sample that can be reliably differentiatedfrom blank matrix and identified by the analytical method.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 119 Standard for the Analytical Scope and Sensitivity of Forensic Toxicological Testing of Blood in Medicolegal Death Investigations. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

An estimate of the lowest concentration of an analyte in a sample that can be reliably differentiated from blank matrix and identified by the analytical method.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 113 Standard for Identification Criteria in Forensic Toxicology. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2022. Source link

An estimate of the lowest concentration of an analyte in a sample that can be reliably differentiated from blank matrix and identified by the analytical method.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 121 Standard for the Analytical Scope and Sensitivity of Forensic Toxicology Urine Testing in Drug-Facilitated Crime Investigations. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

An estimate of the lowest concentration of an analyte in a sample that can be reliably differentiated from blank matrix and identified by the analytical method

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 054 Standard for a Quality Control Program in Forensic Toxicology Laboratories. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

An estimate of the lowest concentration of an analyte in a sample that can be reliably differentiated from blank matrix and identified by the analytical method.

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

Estimate of the lowest concentration of an analyte in a sample that can be reliably differentiated from blank matrix and identified by the analytical method

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 056 Standard for Evaluation of Measurement Uncertainty in Forensic Toxicology . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link

Estimate of the lowest concentration of an analyte in a sample that can be reliably differentiated from blank matrix and meets identification criteria.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 017 Standard for Metrological Traceability in Forensic Toxicology. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2025. Source link

lowest amount of an analyte that is detectable with a given confidence level.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

1) For a test, the point at which the sensitivity of the test is such that the quantity or concentration of a component present is insufficient to produce a positive test result or be detected. 2) For instrumental analysis, the point below which it is not possible to reliably distinguish analytical signal data from instrument background noise; typically defined as three times the standard deviation of the average background noise; The LOD may be calculated to aid in setting an analytical threshold for the reporting and interpretation of alleles in a DNA profile electropherogram.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 046 Wildlife Forensics Validation Standards—STR Analysis. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2019. Source link

A site designed to test the canine's ability to search and indicate independently of the handler.

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

Quantification technique to estimate the actual number of individuals based on the number of paired and unpaired bones.

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

Utilization of a canine to scent discriminate among a predetermined sequence of items with target odor/scent(s) versus non-target odor/scent(s).

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

Linear pulse code modulation is a digital encoding methodology for audio waveformsbased upon amplitudes of the signal.
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

Consists of finding the best-fit linear relationship between the instrument response (Y) and the concentration of the analyte in the calibrator (X)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 054 Standard for a Quality Control Program in Forensic Toxicology Laboratories. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Method of estimating stature based on a statistical procedure for describing a relationship between stature and bone dimension that can be used to predict the former from the latter.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 045 Standard for Stature Estimation in Forensic Anthropology. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2019. Source link

A thin layer of butyl rubber compound that holds the air inside the tire.
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 borders defining the differences in fire effects on materials between the affected area and adjacent, less-affected areas.

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 nonrandom association, in a population, of alleles at different loci.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 046 Wildlife Forensics Validation Standards—STR Analysis. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2019. Source link

Document(s) exposed to or immersed in liquid(s).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 128 Standard for the Preservation and Examination of Liquid Soaked Documents. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2022. Source link

Equipment, materials, or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of products or services, that maintains periodic inspection of production of listed equipment or materials or periodic evaluation of services, and whose listing states that either the equipment, material, or service meets appropriate designated standards or has been tested and found suitable for a specified purpose.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
NFPA 1033:2022 Standard for Professional Qualifications for Fire Investigator. The National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA, 2022. Source link

the time over which the energy dispersive X-ray spectroscopy electronics are available to accept and process incoming X-rays. Live time is often expressed as a percentage of real time.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

the time during which an energy dispersive X-ray spectrometer is available to accept and process incoming X-rays.
Discussion—Live time is often expressed as a percentage of real time, in seconds.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732-24e1 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2024. Source link
Reprinted, with permission, from ASTM E1732-24e1 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org

A person’s recorded height, which may be derived from various sources including self-reported stature, family remembrance, or direct measurement.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 045 Standard for Stature Estimation in Forensic Anthropology. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2019. Source link

Utilization of a trailing canine to determine if a matching scent is located at a specific site or not by using a scent article.

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

Utilization of a trailing canine to determine if an associated scent is located at a specific site or not by using a scent article.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 024 Standard for Training and Certification of Canine Detection of Humans: Location Check Using Pre‐scented Canines. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

A test involving one odor per 0.3 meters (1 foot), 1 minute per odor.

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
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