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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.
Searches term name.
Searches standard designation number.
Displaying 1751 - 1800 of 2299

The essential skills one must have in order to perform a specific task.

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

Remnants of a target substance that can be recovered and identified.

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

Formed by the deposition of a substance from the footwear or tire onto another surface.
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

Odor/scent that originated from any substance/subject that may or may not be physically recoverable or detectable by other means. The odor/scent that originated from a target substance/subject and lingers after the target substance/subject has been removed or has totally decomposed (as in the case of human remains).

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

Scent that originated from any subject that may or may not be physically recoverable or detectable by other means. The scent that originated from a target subject and lingers after the target subject has been removed or has totally decomposed (as in the case of human remains).

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

Scent that originated from any subject that may or may not be physically recoverable or detectable by other means. The scent that originated from a target subject and lingers after the target subject has been removed or has totally decomposed (as in the case of human remains).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 026 Standard for Training and Certification of Canine Detection of Humans: An Aged Trail Using Pre-scented Canines. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Scent that originated from any subject that may or may not be physically recoverable or detectable by other means. The scent that originated from a target subject and lingers after the target subject has been removed or has totally decomposed (as in the case of human remains).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 027 Standard for Training and Certification of Canine Detection of Humans: Patrol Canine Team. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Related to breathing and exchange of oxygen and carbon dioxide.

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

Related to breathing and exchange of oxygen and carbon dioxide.

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 behavior that a canine has been trained to exhibit upon locating the source of a target odor/scent. This behavior may be either passive (sit, stare, down, point) or active (bite, bark, scratch, jump, etc.).

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

A behavior that a canine has been trained to exhibit upon locating the source of a target odor/scent. This behavior may be either passive (sit, stare, down, point) or active (bite, bark, scratch, jump, etc.). (See indication.)

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

The accountability of a person or other entity for the event or sequence of events that caused the fire or explosion, spread of the fire, bodily injuries, loss of life, or property damage.

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 product of the forensic service provider. This term is broad and includes observations, data, calculations, interpretations, and opinions.

Date Added to Lexicon
Committee Source
FSSB

A used tire to which a new tread has been added.
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

Behaviors associated with finding and returning prey or objects back to the canine handler or social group.

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

Behaviors associated with finding and returning prey or objects back to the canine handler or social group.

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

The innate impulse to find and bring prey.

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 subconscious impulse to find and bring prey to the pack leader.

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 fully corrected version of the original Cambridge Reference Sequence (GenBank# J01415 0 gi:337188) of Anderson et al. (1981) of the human mitochondrial genome (mtDNA), also referred to as the Anderson sequence. The rCRS is GenBank sequence NC_012920; it differs from the original CRS and other complete mtDNA GenBank sequences in that it has eighteen corrected or confirmed nucleotides. It is used for reporting human mtDNA sequences, generally by denoting the differences observed from the rCRS.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 140 Standard for Training in Forensic Human Mitochondrial DNA Analysis, Interpretation, Comparison, Statistical Evaluation, and Reporting. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

The presentation of a desired or preferred article, toy, food, or praise given to the canine once the detector canine has alerted and responded to the odor(s)/scent(s) for which the canine is trained to detect/locate.

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 presentation of an article, toy, food, or praise given to the canine once the detector canine has alerted and responded to the odor(s)/scent(s) for which the canine is trained to detect/locate.

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

Red, Green, Blue used to represent color pixels comprised of a specified number of bitsto represent each of these primary color components.

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

Row of continuous rubber or disconnected tire tread blocks that run circumferentially around a tire to form the tread pattern, further distinguished as center, intermediate, or shoulder ribs.
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

A raised portion of the epidermis on the palmar or plantar skin, consisting of one or moreconnected ridge units of friction ridge skin.

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 section of a ridge that connects two minutiae; a single non-intersecting portion of askeletonized image.

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

See skeletonized image.

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 Resource Interchange File Format is a generic file container format which can be used to store 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

The Resource Interchange File Format is a generic file container format that issometimes used in audio and video recordings. The most common implementation ofRIFF is WAV, which uses the file extension '.wav'

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 diameter of the rim that supports the tire bead and is expressed in inches, such as 13', 16', 16.5' etc.
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 uncertain event or condition that, if it occurs, has a negative effect on a softwares reliability and performance.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 114 Best Practice Recommendations for Internal Validation of Software used in Forensic DNA Laboratories. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2022. Source link

The degree of peril; the possible harm that might occur that is represented by the statistical probability or quantitative estimate of the frequency or severity of injury or loss.

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 systematic process for deciding the risk level associated with a particular software or module.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 114 Best Practice Recommendations for Internal Validation of Software used in Forensic DNA Laboratories. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2022. Source link

A commercial device for measuring foot length and width.
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

Experiments performed to measure the capability of a procedure to remain unaffected by small but deliberate variations in method parameters and provide an indication of reliability during normal usage.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 077 Standard for the Developmental and Internal Validation of Forensic Serological Methods. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

Region of interest.

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 linear distance traveled by a tire in one revolution under load.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 021 Best Practices for the Preparation of Test Impressions from Footwear and Tires. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

The linear distance traveled by a tire in one revolution under load.
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

A fingerprint image collected by rolling the finger across a livescan platen or paperfingerprint card from nail to nail. Rolls may be from livescan devices or scanned frompaper fingerprint cards.

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 commercial product, which is a seven-mil Estar film base material designed to wet rollers andpick up loose particles on all types of roller transport photo-processing machines used along withfingerprint powder to produce known impressions of footwear and tires.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 021 Best Practices for the Preparation of Test Impressions from Footwear and Tires. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link

A seven-mil Estar film base material designed to wet rollers and pick up loose particles on all types of roller transport photo-processing machines used along with fingerprint powder to produce known impressions of footwear and 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

See flameover.

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

Canine training conducted with regularity that maintains the canine's operational capabilities.

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

Canine training conducted with regularity that maintains the canine's operational capabilities.

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

set of samples contemporaneously analyzed (unbroken sequence) as part of an experiment or calibration

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 055 Standard for Breath Alcohol Measuring Instrument Calibration . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link

A document providing comprehensive information about a substance or mixture for using in workplace chemical management as adopted by the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). NOTE Previously known as a material safety data sheet (MSDS).

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

A document providing comprehensive information about a substance or mixture for using in workplace chemical management as adopted by the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). Note: Previously known as a Material Safety Data Sheet (MSDS).

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 action by the handler, canine or canine team that if done in operational environment, could place the canine team in jeopardy.

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

Obtain the values of a function for regularly or irregularly spaced distinct values fromits domain. From: ISO 2382-2:1976.

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 sample for which the identity of the donor is established and which is used for comparison purposes.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E3175-23 Standard Practice for Training in the Forensic Examination of Hair by Microscopy. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2023. 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 sample of known hairs that is insufficient in quality or quantity to reflect a representative range of characteristics or traits.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E3175-23 Standard Practice for Training in the Forensic Examination of Hair by Microscopy. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2023. 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