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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

Displaying 901 - 950 of 3629
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Deprecated

The record type / field / subfield / information item / value / file shall not be used whenclaiming conformance to this version of the standard. (different than 'legacy' )

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
Deprivation

The restriction of access to something desired by the canine such as food, social companions, or toys.

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
Derived Representation

Biometric type record derived from a Type-20 source representation record, which maybe another Type-20 record from which other biometric type records are derived.

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
descender

A stroke that extends below the baseline of the body of the letter formation. (SWGDOC T01)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Design
The manufactured pattern of a footwear outsole or tire tread. Design is a class characteristic.
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
Design/Size Relationship
The tendency for a footwear outsole or tire tread design to have either more design elements, or larger design elements, or both, as the footwear or tire size increases throughout the size range produced.
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
designating authority

organization established within government, or empowered by government, to designate conformity assessment bodies (4.6) and to suspend or withdraw their designation (9.2)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO 17000:2020 Conformity assessment — Vocabulary and general principles. International Organization for Standardization BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2020. 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
designation

governmental authorization of a conformity assessment body (4.6) to perform specified conformity assessment activities
Note 1 to entry: Designation is sometimes referred to as “notification”.
 

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO 17000:2020 Conformity assessment — Vocabulary and general principles. International Organization for Standardization BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2020. 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
Desorption
the process of removing an adsorbed material from the solid (adsorbent) on which it is adsorbed. (See also elution.) Discussion—Desorption may be accomplished by heating, by reduction of pressure, by the presence of another more strongly adsorbed substance, or by a combination of these means.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Destructive Testing
testing, examination, re-examination, disassembly, or other actions likely to alter the original, as-found nature, state or condition of items of evidence so as to preclude or adversely affect additional examination and testing.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
detached letter

A letter, which when alone, constitutes a word, such as "I" and "A". Also, a letter which is not connected to the remaining letters of a word, such as the capital letter in some names.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Detailing

(1) A handler technique by which the handler will present productive area to the canine, usually by pointing or hand and arm sweeps. (2) Used to search a particular area in more detail or when a canine may have walked by to prompt the canine to search in a particular direction. (3) Used to prompt a canine to search high and low productive areas.

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
Detection
an analytical signal from a recognized analyte was generated and can be tentatively identified.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Detection

(1) sensing the existence of a fire, especially by a detector from one or more products of the fire, such as smoke, heat, infrared radiation, and the like. (2) the act or process of discovering and locating a fire.

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
Detection Agent
A chemical marker added to plastic explosives to aid in detection by either instrumental or canine screening; also known as detection taggant. Discussion—Detection agents include DMDNB; o-mononitrotoluene; p-mononitrotoluene; and EGDN.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Detector/Detection Canine Detector Dog

A canine trained to detect and alert to the presence of certain scents or odors for which it has been trained. May be referred to as a law enforcement or search and rescue service canine, which is not to be confused with canines covered by the Americans with Disabilities Act (ADA).

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
Deterrent
a compound to slow the burning rate of a powder.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Detonating Cord
a flexible cord containing a central core of high explosives used to initiate high explosives along the cord's length; also known as detcord/primacord.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Detonation
propagation of a reaction zone at a velocity that is greater than the speed of sound in the unreacted medium.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Detonation

Propagation of a combustion zone at a velocity greater than the speed of sound in the unreacted medium. [68, 2018]

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
Development
the movement of the mobile phase through the adsorbent layer to form a chromatogram.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Developmental Stages Of Dental Growth

Intervals in the morphologic appearance of teeth as the crown or root mature.

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
developmental validation

The acquisition of test data and determination of conditions and limitations of a new methodology.

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
Developmental Validation

The acquisition of test data and determination of conditions and limitations of a new methodology; this generally occurs while the conditions and parameters are being worked out prior to the establishment of a defined assay, procedure or product. Internal validation studies follow developmental validation studies.

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
Developmental Validation

The acquisition and evaluation of test data for the determination of the conditions and/or limitations under which a novel method will achieve consistent results.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 063 Implementation of 3D Technologies in Forensic Firearm and Toolmark Comparison Laboratories. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link
Developmental Validation

The acquisition of test data and determination of conditions and limitations of a new methodology; this generally occurs while the conditions and parameters are being worked out prior to the establishment of a defined assay, procedure or product. Internal validation studies typically follow developmental validation studies.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 038 Standard for Internal Validation of Forensic DNA Analysis Methods. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link
Developmental Validation

The accumulation of test data to demonstrate that established parameters, software settings, formulae, algorithms and mathematical functions perform as expected. Developmental validation should also demonstrate any known limitations of the system. Developmental validation may be conducted outside the laboratory planning to use it (i.e., by the manufacturer, developer, or other testing laboratory) and will precede any internal validations

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 018 Standard for Validation of Probabilstic Genotyping Systems. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link
Deworming

(Replacing worming) is the giving of an anthelmintic drug (a wormer, dewormer, or drench) to a human or animal to rid them of helminths parasites, such as roundworm, flukes and tapeworm.

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
diacritic

Those dots, lines, and swoops that appear above, below, and occasionally even beside certain letters in words. The purpose of diacritical marks is to change the sound of the individual letter they are marking or to change the meaning of an entire word by changing which syllable is accented. Often incorrectly used to describe such characteristics as the "i" and "j" dot. Déjà vu. 

diacritic image
Credit: Academy Standards Board
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
diagnostic imaging

Radiographs, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), ultrasound, and other diagnostic modalities used to assess and document condition, injury, or disease processes.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 169 Standard for Clinical Veterinary Forensic Examination. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
Diagnostic Ion

A MS or MS/MS molecular ion or fragment ion whose presence and abundance are characteristic of the targeted analyte.

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
Diagnostic Ion

A MS or MS/MS molecular ion or fragment ion whose presence and relative abundance are characteristic of the targeted analyte.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 098 Standard for Mass Spectral Analysis in Forensic Toxicology. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2023. Source link
diagnostic ion

MS or MS/MS molecular ion or fragment ion whose presence and relative abundance are characteristic of the targeted analyte

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB Technical Report 208, Forensic Toxicology: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
diagonal stroke

A slanting stroke, as in the center stroke of the printed capital "N".

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Diary

A list giving the start and stop times of speech segments within the voice signal,pertaining to the subject of the record. Diarization of segments from multiple speakersrequires multiple Type-11 records, one for each speaker. These multiple Type-11records may be contained in a single transaction, as long as the transaction is focusedupon a single subject.

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
dichroic filters

A filter with two transmission bands. These bands are usually widely separated, and can be of significantly different size. (SWGDOC M01)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Dichroism
the property of exhibiting different colors, especially two different colors, when viewed along different axes by plane polarized light.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Dicom

The standard Digital Imaging and Communications in Medicine published by the National Electrical Manufacturers Association (NEMA).

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
Dicos

The standard Digital Imaging and Communications in Security published by theNational Electrical Manufacturers Association (NEMA)

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
Die Cut
Outsoles or other footwear components produced by forcing a sharpened steel die through preformed outsole material with the assistance of a clicker machine.
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
dielectric printing process

Nonimpact printing technique in which specially treated paper consisting of a conductive base layer coated with a nonconductive thermoplastic material is used to hold an electric charge usually applied directly by a set of electrode styli. The electric charge corresponds to the latent image of the original. Following the charging step, the paper is imaged by a toner system similar to that of electrostatic copying devices. This technique is sometimes called electrographic, and is currently used on general purpose non-impact printers, plotting and facsimile devices. (SWGDOC E05)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
difference

Consistent, repeated dissimilarity in a structural or other characteristic or feature, that cannot be reasonably explained as variation or deviation from natural variation of a single source or class.

Date Added to Lexicon
Standard Source (Designation Number Publisher, Place, Year.)
ASB Technical Report 071 AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
differential diagnosis

A process through which all possible causes of a skeletal or dental anomaly/abnormality are considered. Through a careful process of elimination, only the most likely causes remain to aid in the identification of the pathological or anomalous condition(s) of the skeleton.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB Technical Report 214, Forensic Anthropology: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2026. Source link
Differential Lysis And Extraction

A method of DNA extraction where sperm and non-sperm cells are digested separately based on the different composition of the cell membranes resulting in the generation of a sperm fraction and a non-sperm cell fraction.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 023 Standard for Training in Forensic DNA Isolation and Purification Methods. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link
Diffraction
phenomenon that arises as a result of passing radiation through the "lens" of the microspectrometer and past the edges of objects such as apertures and the specimen. It causes radiation to deviate from its usually straight line causing blurring of what should be sharp images.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Diffraction Peaks
spectral artifacts that result from preferential diffraction of tube X-rays into the detector as a result of striking a crystalline sample. Discussion—Diffraction peaks vary in energy and intensity depending on orientation of the crystalline planes with respect to the beam angle.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Diffractometer
an instrument that records either powder or single-crystal X-ray diffraction patterns.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 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
Diffuse Fuel

A gas, vapor, dust, particulate, aerosol, mist, fog, or hybrid mixture of these, suspended in the atmosphere, which is capable of being ignited and propagating a flame front.

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
diffuse reflection

Diffusion by reflection in which, on the macroscopic scale, there is no regular reflection. (CIE S 017/E:2011 ILV)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Diffusion Flame

A flame in which fuel and air mix or diffuse together at the region of combustion.

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
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