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.
In computer forensics, a standard structure by which data is organized in a file for a specific purpose
In computer forensics, a standard structure by which data is organized in a file for a specific purpose.
In computer forensics, the data within a file that contains identifying information about the file and possibly metadata with information about the file contents
In computer forensics, the data within a file that contains identifying information about the file and possibly metadata with information about the file contents.
In computer forensics, the data between the logical end of a file and the end of the last storage unit for that file
In computer forensics, the data between the logical end of a file and the end of the last storage unit for that file.
In computer forensics, an identifier used to uniquely identify a file object within a directory object in a filesystem
In computer forensics, an identifier used to uniquely identify a file object within a directory object in a filesystem.
In computer forensics, a specified method for naming, storing, organizing, and accessing files on logical volumes.
In computer forensics, a specified method for naming, storing, organizing, and accessing files on logical volumes
See weft yarns (filling).
An inorganic material that is added to a tape to modify a physical property or reduce cost
An inorganic material that is added to a tape to modify a physical property or reduce cost
Last beam-restricting orifice in an electron optical column
A behavior that a canine has been trained to exhibit in the presence of a target scent source. This behavior may be either passive (sit, stare, down, point, etc.) or active (bite, bark, scratch, jump, etc.). Also known as a trained final response. (See 3.4 alert.)
A behavior that a canine has been trained to exhibit in the presence of a target scent source. This behavior may be either passive (sit, stare, down, point, etc.) or active (bite, bark, scratch, jump, etc.). Also known as a trained final response. (See 3.4 alert.)
A behavior that a canine has been trained to exhibit in the presence of a target scent source. This behavior may be either passive (sit, stare, down, point, etc.) or active (bite, bark, scratch, jump, etc.). Also known as a trained final response. (See 3.4 alert.)
A behavior that a canine has been trained to exhibit in the presence of a target odor/scent source. This behavior may be either passive (sit, stare, down, point, etc.) or active (bite, bark, scratch, etc.). Also known as a trained final response.
A behavior that a canine has been trained to exhibit in the presence of a target odor/scent source. This behavior may be either passive (sit, stare, down, point, etc.) or active (bite, bark, scratch, etc.). Also known as a trained final response. NOTE For EDC, EDC w/PSC, and PSC refer to 4.2.1.3.
A behavior that a canine has been trained to exhibit in the presence of a target odor/scent source. This behavior may be either passive (sit, stare, down, point, etc.) or active (bite, bark, scratch, jump, etc.). Also known as a trained final response. (See alert, indication.)
An image or impression of the friction ridges of all or any part of a finger or thumb.
A manufactured product ready for use
A manufactured product ready for use.
The time in minutes, determined under specific laboratory conditions, at which the stud or joist in contact with the exposed protective membrane in a protected combustible assembly reaches an average temperature rise of 121C (250F) or an individual temperature rise of 163C (325F) as measured behind the protective membrane nearest the fire on the plane of the wood.
A rapid oxidation process, which is an exothermic chemical reaction, resulting in the evolution of light and heat in varying intensities.
a rapid oxidation process, which is a chemical reaction resulting in the evolution of light and heat in varying intensities (see combustion).
a rapid oxidation process, which is a chemical reaction resulting in the evolution of light and heat in varying intensities (see combustion). NFPA 921, 3.3.68
The process of determining the origin, cause, development, responsibility, and, when required, a failure analysis of a fire or explosion.
The process of determining the origin, cause, development, responsibility, and, when required, a failure analysis of a fire or explosion.
The boundary of fire effects within a scene in which the area of origin will be located. The fire area is characterized by identifying the border between damaged and undamaged areas, which are distinguishable by fire effects and patterns created by flame, heat, and smoke.
The circumstances, conditions, or agencies that bring together a fuel, ignition source, and oxidizer (such as air or oxygen) resulting in a fire or a combustion explosion.
The study of chemical processes that occur in fires including changes in state, decomposition, and combustion.
The study of chemical processes that occur in fires including changes of state, decomposition, and combustion.
material of interest at a fire scene that can be collected by an investigator as evidence to analyze.
material of interest at a fire scene that can be collected by an investigator as evidence to analyze.
the science related to the examination of fire debris samples performed to potentially detect and identify ignitable liquid residues (ILR).
the science related to the examination of fire debris samples performed to potentially detect and identify ignitable liquid residues (ILR).
The detailed study of how chemistry, fire science, and the engineering disciplines of fluid mechanics and heat transfer interact to influence fire behavior.
The detailed study of how chemistry, fire science, and the engineering disciplines of fluid mechanics and heat transfer interact to influence fire behavior.
The observable or measurable changes in or on a material as a result of a fire.
Any situation, process, material, or condition that can cause a fire or explosion or that can provide a ready fuel supply to augment the spread or intensity of a fire or explosion, all of which pose a threat to life or property.
The process of determining the origin, cause, and development of a fire or explosion
The process of determining the origin, cause, and development of a fire or explosion.
An individual who has demonstrated the skills and knowledge necessary to conduct, coordinate, and complete a fire investigation.
An individual who has demonstrated the skills and knowledge necessary to conduct, coordinate, and complete a fire investigation.
A structured approach to predicting one or more effects of a fire.
The physical changes, or identifiable shapes, formed by a fire effect or group of fire effects.
See fire spread.
Systems, devices, and equipment used to detect a fire and its by-products, actuate an alarm, or suppress or control a fire and its by-products, or any combination thereof.
The process of recreating the physical scene during fire scene analysis investigation or through the removal of debris and the placement of contents or structural elements in their pre-fire positions.