OSAC (Fire and Explosion)
Definition
Organisation of Scientific Area Committees, Fire and Explosion Investigation Subcommittee, under NIST. Develops and publishes standards and needs statements for fire investigation methodology, including opinion language criteria for fire debris laboratory reports.
- Parent body
- NIST OSAC
- Focus area
- Fire and explosion investigation methodology
- Notable product
- Opinion language criteria for fire debris laboratory reports
- Document type
- Standards and needs statements
Common questions
What is a 'needs statement' in OSAC's process?+
It is a subcommittee document identifying a gap in existing forensic standards or research, used to direct funding and standards-development priority before a formal standard is drafted.
Why does opinion language matter for a fire debris report?+
Standardised opinion language keeps an examiner's stated confidence level tied to the strength of the underlying data, reducing the risk that a report implies more certainty than the ASTM E1618 classification actually supports.
Related terms
- ASTM E1618
- Standard Test Method for Ignitable Liquid Residues in Extracts from Fire Debris Samples by Gas Chromatography-Mass Spectrometry. The active analytical standard defining...
- DB-5 Column
- A gas chromatography capillary column with a 5% phenyl-95% dimethylpolysiloxane stationary phase, the standard column for fire debris GC-MS analysis. Provides adequate...
- Extracted Ion Profile (EIP)
- A GC-MS chromatographic display plotting only ions of a specified m/z value against retention time, effectively filtering out all compounds that do...
- Ignitable Liquid
- In fire debris analysis, any flammable liquid that could serve as an accelerant. E1618 classifies ignitable liquids into eight categories based on...
- Isoparaffinic Products
- An E1618 category of ignitable liquid dominated by branched-chain (isoparaffinic) alkanes with minimal aromatic or n-alkane content. Examples include Isopar solvents and...
- Passive Headspace Concentration (PHC)
- ASTM E1412 extraction method. The sealed evidence container is heated at 60-80°C; volatilised hydrocarbons adsorb onto an activated charcoal strip suspended in...
- SWGFEX
- Scientific Working Group for Fire and Explosion Investigation. A US-based multidisciplinary body that developed best practice guides for fire debris collection, canine...
- Unresolved Complex Mixture (UCM)
- The broad hump of hundreds of co-eluting cycloalkane and isoalkane compounds in the TIC of heavy petroleum products (diesel, heavy fuel oil,...
- Weathering (Evaporative)
- The preferential loss of low-boiling components from an ignitable liquid by evaporation. Shifts the GC-MS pattern toward heavier components and can cause...