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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 601 - 650 of 3121

current in the condenser lens changes the spot size or diameter of the electron beam.

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) A general term that explains how animals learn the connection between stimuli, events, and actions. (2) Physical conditioning is a process by which an animal develops cardiovascular and respiratory stamina.

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

As a result of classical conditioning, an event that is initially neutral will acquire aversive properties because it is paired with other aversive events.

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

Fear in response to a previously neutral stimulus caused by aversive conditioning and/or event.

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 previously neutral stimulus that has become reinforcing because of its association with a primary reinforcer. A stimulus that becomes a reinforcer because it is paired with another reinforcer, usually a primary reinforcer. If conditioned reinforcers are not maintained by periodically pairing them with primary reinforcers, they will lose their reinforcing value.

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

In classical or Pavlovian conditioning, a conditioned response (CR) is produced by pairing a conditioned stimulus (CS) with an unconditioned stimulus (UCS). (See 3.74 classical conditioning.)

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

In classical or Pavlovian conditioning a previously neutral stimulus (NS) becomes the conditioned stimulus (CS) and evokes the conditioned response (CR) after it is repeatedly paired with an unconditioned stimulus (UCS). (See classical conditioning.)

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

Heat transfer to another body or within a body by direct contact.

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

(1) A conditioned level of ability to operate independently in different environments as developed with training. (2) The innate ability of each canine to operate independently in different environments.

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 alert for which the presence of a trained odor/scent can be verified or corroborated. Also referred to as a 'hit', 'find' and/or 'positive response'.

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

Verification of search results following a deployment of a canine team(s).

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

Verification of search results following a deployment of a canine team(s).

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

Verification of search results following a deployment of a canine team(s).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 088 General Guidelines for Training, Certification, and Documentation of Canine Detection Disciplines. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

Verification of search results following a deployment of a canine team(s).

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 092 Standard for Training and Certification of Canine Detection of Explosives. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Verification of search results following a deployment of a canine team(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

particle(s) relocated, analyzed, and classified by the analyst as pGSR based on appropriate (as specified in Practice E1588) constituent elements and morphology.

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 test that is specific for the presence of a body fluid, stain, or residue of interest, and reduces or eliminates false positive results.

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

A test that is specific for the presence of a body fluid, stain, or residue of interest, and reduces or eliminates false positive results

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 110 Standards for Training in Forensic Serological Methods. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

A condition in which two or more events cause incompatible responses.

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 condition in which two or more examiners disagree on a suitability decision or source conclusion.

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

Surface topography measurement method consisting of a confocal microscope with chromaticobjective integrated with a detection device (e.g., spectrometer) whereby the surface height at asingle point is sensed by the wavelength of light reflected from the surface.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 061 Firearms and Toolmarks 3D Measurement Systems and Measurement Quality Control. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Surface topography measurement method whereby a pinhole object illuminated by the light sourceis imaged by a lens onto the surface being studied and the light is reflected back through the lens toa second pinhole placed in front of a detector and acting as a spatial filter.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 061 Firearms and Toolmarks 3D Measurement Systems and Measurement Quality Control. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

Fulfillment of specified requirements.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO/IEC Guide 2:2016 Standardization and related activities -- General vocabulary. International Organization for Standardization BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2016. 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

Demonstration that specified requirements relating to a product, process, system, person, or body are fulfilled. Conformity assessment may include testing, inspection, and certification, as well as the accreditation of conformity assessment bodies. First-party conformity assessment activity is performed by the person or organization that provides the object. Second-party conformity assessment activity is performed by a person or organization that has a user interest in the object. Persons or organization performing second-party conformity assessment activities include, for example, purchasers or users of products, or potential customers seeking to rely on a suppliers management system, or organizations representing those interests. Third party conformity assessment activity is performed by a person or body that is independent of the person or organization that provides the object, and of user interests in that object.

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

A body, other than an accreditation body, that performs conformity assessment services.

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

Equivalence of conformity assessment results is the sufficiency of different conformity assessment results to provide the same level of assurance of conformity with regard to the same specified requirements. Recognition of conformity assessment results is the acknowledgement of the validity of a conformity assessment result provided by another person or body. Acceptance of conformity assessment results is the use of a conformity assessment result provided by another person or body. Unilateral arrangement is an arrangement whereby one party recognizes or accepts the conformity assessment results of another party. Bilateral arrangement is an arrangement whereby two parties recognize or accept each other's conformity assessment results. Multilateral arrangement is an arrangement whereby more than two parties recognize or accept one another's conformity assessment results. Agreement groups are bodies that are signatories to the agreement on which an arrangement is based. Reciprocity is a relationship between two parties where both have the same rights and obligations towards each other. Reciprocity can exist within a multilateral arrangement comprising a network of bilateral reciprocal relationships. Although rights and obligations are the same, opportunities emanating from them can differ, which can lead to unequal relationships between parties. Equal treatment is treatment accorded to products or processes from one supplier that is no less favourable than that accorded to like products or processes from any other supplier, in a comparable situation. National treatment is treatment accorded to products or processes originating in other countries that is no less favourable than that accorded to like products or processes of national origin, in a comparable situation. Equal and national treatment is treatment accorded to products or processes originating in other countries that is no less favourable than that accorded to like products or processes of national origin, or originating in any other country, in a comparable situation.

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

Conformity assessment system related to specified objects of conformity assessment, to which the same specified requirements, specific rules, and procedures apply. Conformity assessment schemes may be operated at international, regional, national, or sub-national level. Access to a system or scheme is the opportunity for an applicant to obtain conformity assessment under the rules of the system or scheme. A participant in a system or scheme is a body that operates under the applicable rules without having the opportunity to take part in the management of the system or scheme. A member of a system or scheme is a body that operates under the applicable rules and has the opportunity to take part in the management of the system or scheme.

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

Rules, procedures, and management for carrying out conformity assessment. Conformity assessment schemes may be operated at international, regional, national, or sub-national level.

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

A characteristic present at birth.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 134 Standard for Analyzing Pathological Conditions and Anomalies in Forensic Anthropology . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2021. Source link

A value that serves as an agreed-upon reference for comparison that is based on results of laboratories participating in the proficiency test. 

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 153 Standard Practices for Proficiency Testing for Forensic Toxicology Laboratories and Breath Alcohol Programs. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904 , 2023. Source link

A type of examination in which a reported decision or conclusion is determined that reflects the collective judgement of a group of examiners.

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

Consistent measures are those where repeated measurements of the same thing produce the same results. (See reliability.)

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

Obtaining a similar output, within an acceptable limited range of variation (as defined by the laboratory protocol and validation data), when using the same methods and procedures over time.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 123 Standard for Routine Internal Evaluation of a Laboratory’s DNA Interpretation and Comparison Protocol. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link

Obtaining a similar output, within an acceptable limited range of variation (as defined by the laboratory protocol and validation data), when using the same methods and procedures over time

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 020 Standard for Validation Studies of DNA Mixtures, and Development and Verification of a Laboratory's Mixture Interpretation Protocol. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2018. Source link

particles that have compositions that are found in GSR and also arise from other non-firearm sources.
Discussion—Particles within this group are produced through the operation of a variety of processes, equipment, or devices and can be found in the environment with varying levels of frequency.

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

This is a NIEM schema that adds additional constraints and restrictions to components.A constraint schema was used in the 2008 version of the standard to add cardinalityconstraints to schemas that were automatically generated by a NIEM tool called SSGT(Subset Schema Generator Tool). The tool has been updated to directly specifycardinality constraints in the NIEM subset schema, so constraint schemas are no longerprovided. However, an implementer is permitted to define their own constraint schemato add further restrictions to the standard. An example is to only allow certain recordtypes in a transaction.

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 discussion or interaction initiated by an examiner seeking guidance for the purpose of interpreting an image or comparison.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 145 Standard for Consultation During Friction Ridge Examination. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO
, 2023. Source link

A format that describes how the data and metadata are stored in a computer 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

The unintentional introduction of exogenous DNA or other biological material in a DNA sample, PCR reaction, or item of evidence; the exogenous DNA or biological material could be present before the sample is collected or introduced during collection or testing of the sample.

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

An odor/scent that is inadvertently or purposefully introduced. Contamination can include the following: contamination of a search area with a target scent or contamination of a target aid with competing odor/scent.

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

An odor/scent that is inadvertently or purposefully introduced. Contamination can include the following: contamination of a search area with a target scent or contamination of a target aid with competing odor/scent.

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

The unintentional introduction of exogenous materials or substances into a test sample.

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

When an odor/scent is inadvertently or purposefully introduced. Contamination can include the following: contamination of a search area with a target odor/scent or contamination of a target aid with competing odor/scent.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 092 Standard for Training and Certification of Canine Detection of Explosives. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2021. Source link

The unintentional introduction of exogenous materials or substances into a test sample.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 110 Standards for Training in Forensic Serological Methods. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2020. Source link

The unintentional introduction of exogenous DNA or other biological material in a DNA sample, PCR reaction, or item of evidence; the exogenous DNA or biological material could be present before the sample is collected or introduced during collection or testing of the sample.

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

When an odor/scent is inadvertently introduced. Contamination can include the following: contamination of a search area with a target odor/scent or contamination of a target aid with competing odor/scent.

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

Exogenous DNA in an extract, polymerase chain reaction, or item of evidence, which may be present before the sample is collected or introduced during collection or testing of the sample.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 175 Standard for Interpreting, Comparing and Reporting DNA Test Results Associated with Failed Controls and Contamination Events . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link

Exogenous DNA or other biological material in a DNA sample, PCR reaction, or item of evidence; present before the sample is collected or introduced during collection or testing of the sample

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 171 Best Practice Recommendations for the Management and Use of Quality Assurance DNA Elimination Databases in Forensic DNA Analysis . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link

Undesirable introduction of a substance to an item at any point in the forensic process. NOTE This includes undesirable transfer of a substance within an item or between items, also referred to as cross-contamination. (ISO 21043-1)

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

Of target: any odor/scent not ordinarily part of a target odor/scent signature. Of area: any odor/scent not normally part of the context of that area.

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