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.
Clear plastic sheet with a pressure sensitive adhesive layer.
A body or stream of gaseous material involved in the combustion process and emitting radiant energy at specific wavelength bands determined by the combustion chemistry of the fuel. In most cases, some portion of the emitted radiant energy is visible to the human eye.
A hot, usually luminous zone of gas that is undergoing combustion.
The flaming leading edge of a propagating combustion reaction zone.
The condition where unburned fuel (pyrolysate) from the originating fire has accumulated in the upper layer to a sufficient concentration (i.e., at or above the lower flammable limit) that it ignites and burns. This can occur without ignition of, or prior to the ignition of, other fuels separate from the origin.
Capable of burning with a flame.
capable of burning with a flame.
The upper or lower concentration limit at a specified temperature and pressure of a flammable gas or a vapor of an ignitible liquid and air, expressed as a percentage of fuel by volume that can be ignited.
A liquid that has a closed-cup flash point that is below 37.8C (100F) and a maximum vapor pressure of 2068 mm Hg (40 psia) at 37.8C (100F). (See also 3.3.34, Combustible Liquid.)
See ignitable liquid.
The range of concentrations between the lower and upper flammable limits.
A fire that spreads by means of a flame front rapidly through a diffuse fuel, such as dust, gas, or the vapors of an ignitible liquid, without the production of damaging pressure.
the lowest temperature corrected to a pressure of 101.3 kPa (760 mm Hg) at which application of an ignition source causes the vapors of a specimen of the sample to ignite under specified conditions of the test.
Discussion—There are several methods for determining the flash point. The preferred method used by authorities in delineating between flammable and combustible liquids is a closed-cup flash point test.
The lowest temperature of a liquid, as determined by specific laboratory tests, at which the liquid gives off vapors at a sufficient rate to support a momentary flame across its surface.
A mixture of strong inorganic oxidizer; such as perchlorate or chlorate salts; and finely divided metal fuel; such as aluminum or magnesium powders; also known as photoflash powder.
Discussion—Sulfur powder; often used as a fuel/tinder; and carbonaceous filler materials can also be present in flash powder.
A transition phase in the development of a compartment fire in which surfaces exposed to thermal radiation reach ignition temperature more or less simultaneously and, given sufficient availability of oxygen, fire spreads rapidly throughout the space, resulting in full room involvement or total involvement of the compartment or enclosed space.
A fingerprint image resulting from the touching of a single finger to a livescan platen orpaper fingerprint card without any rolling motion. Also known as a single-finger plainimpression.
smooth paper backing masking tape (saturated paper tape).
the emission of light by a fiber that has absorbed light or other electromagnetic radiation of shorter wavelength (higher energy).
A process by which radiant flux of certain wavelengths is absorbed and reradiated nonthermally at other, usually longer, wavelengths.
a microscope equipped with a high energy light source (usually a xenon or mercury vapor lamp) and a set of excitation and barrier filters along with a dichromatic mirror, used to induce and observe fluorescence in fibers and other particles or materials.
the distance from the optical center of a lens to its point of focus at the sensor or image plane when focused at infinity.
Surface topography measurement method whereby the sharpness of the surface image (or anotherproperty of the reflected light at optimum focus) in an optical microscope is used to determine thesurface height at each position along the surface.
tissue from a hair follicle that is still attached to the root end of a hair which has been forcibly removed.
The subconscious impulse to work to obtain food.
The innate impulse to work to obtain food.
Pertaining to the use of analytic / scientific techniques to establish or verify identity - inthis standard, it applies to the examination and mark-up of images (sometimes manually).
Related to methods, techniques and processes used to establish conclusions and/or opinions, facts, and findings which can be used for legal proceedings.
Also referenced in ANSI/ASB Standard 169 Standard for Clinical Veterinary Forensic Examination.
The application of science to answer questions of interest to the legal system.
A forensic anthropologist is an individual with at least a masters degree in forensic anthropology,biological anthropology, or related field, and who also has forensic anthropology case experience ortraining involving fragmentary, burned, and otherwise taphonomically-altered human skeletalremains. They also must have training or experience in producing a biological profile (age, sex,stature, ancestry), and interpreting human skeletal trauma.NOTE Board-certified forensic anthropologists possess a Ph.D. in forensic anthropology/biologicalanthropology or related field and are certified by the American Board of Forensic Anthropology (ABFA).
A forensic anthropologist is an individual with at least a masters degree in forensic anthropology, biological anthropology, or related field, and who also has forensic anthropology case experience or training involving fragmentary, burned, and otherwise taphonomically-altered human skeletal remains. They also must have training or experience in producing a biological profile (age, sex, stature, ancestry), and interpreting human skeletal trauma. NOTE Board-certified forensic anthropologists possess a Ph.D. in forensic anthropology/biological anthropology or related field and are certified by the American Board of Forensic Anthropology (ABFA).
Forensic anthropology is the application of anthropological methods and theoryparticularlythose relating to the recovery and analysis of human remainsto resolve legal matters.
Forensic anthropology is the application of anthropological methods and theoryparticularly those relating to the recovery and analysis of human remainsto resolve legal matters.
Any environment where human remains and material associations, potentially relevant in a medicolegal setting, may be recovered, and where a forensic anthropology or forensic archaeology practitioner is requested to assist a jurisdictional authority.
the scientific examination, analysis, comparison, or evaluation of audio.
An autopsy authorized by law, and typically performed under the jurisdiction of a medical examiner or coroner for criminal justice and public health purposes.
creating a bit stream duplicate of the available data from one physical media to another.
An individual who provides an assessment of an individual's dental age based upon accepted methodology. Note: The term 'practitioner' will be used instead of 'Forensic Dental age assessment Practitioner' throughout this document as an abbreviated way to describe an individual who provides an assessment of an individual's dental age based upon accepted methodology.
The use of DNA technologies for the evaluation of biological evidence that may be involved in legal matters.
See image.
That part of dentistry, which deals with the examination, interpretation, and presentation of dental and oral evidence for legal purposes.
A physician who is certified in forensic pathology by the American Board of Pathology (ABP) or who, prior to 2006, has completed a training program in forensic pathology that is accredited by the Accreditation Council on Graduate Medical Education or its international equivalent or has been officially 'qualified for examination' in forensic pathology by the ABP.
A physician who is board-certified in anatomic pathology or anatomic and clinical pathology, as well as forensic pathology.
The practice of medicine in which the principles of pathology are applied to problems of potential legal, public health, or public safety significance; a common function is the performance of autopsies to determine the cause of death and assist in determining the manner of death.
The act of producing an accurate depiction of a scene or physical evidence using photography for the purpose of an investigative or legal proceedings.