1. “Ignitable liquid” is a term defined and introduced in

  1. ASTM E1614
  2. GHS L01
  3. NFPA 921
  4. ASTM E1812

Answer: (3) NFPA 921

Explanation: The only definition of “Ignitable liquid” is discussed in the guidelines by NFPA 921, “Guide for Fire and Explosion Investigations”.

2. Common fire debris limited to recovery of the flammable and combustible liquid has a flash point up to:

  1. ~100°C
  2. ~150°C
  3. ~200°C
  4. ~210°C

Answer: (1) ~100°C

Explanation: Normally, most flashpoints of ignitable liquid are up to 93°C. Combustible liquids with higher (≥93°C; eg olive oil, lubricants) don’t act as initiators of fire but as intensifiers. That’s why going beyond ~100°C for combusting liquid has less interest in relation to arson investigation.

3. Which of the following agency classify ignitable liquids in terms of flash point and boiling point?

  1. ASTM
  2. GHS
  3. NFPA
  4. Both (2) and (3)

Answer: (2) GHS

Explanation: GHS stands for Globally Harmonized System of Classification and Labeling of Chemicals (GHS) and defines the max flashpoint for classification as 93°C.

4. ASTM E1618 states the standard practice for Ignitable liquid residue by

  1. GC-MS method
  2. LC-MS method
  3. Headspace method
  4. All of the above

Answer: (1) GC-MS method

Explanation: ASTM E1618 states the standard test method for ignitable liquid residues in extracts from Fire Debris Samples by Gas Chromatography-Mass Spectrometry. 

5. How many classification schemes are there in ASTM E1618?

  1. 2
  2. 4
  3. 6
  4. 8

Answer: (4) 8

Explanation: There are seven major classes with additionally one class for ignitable liquids that don’t fall in seven major classes or fall in more than one seven major classes. With an additional one, the total classification in ASTM is eight.

[Table] ASTM Standards For Ignitable Liquid Residues

ASTM StandardsStandard Practice For
ASTM E1386Separation of Ignitable Liquid Residues from Fire Debris Samples by Solvent Extraction.
ASTM E1388Sampling of Headspace Vapors from Fire Debris Samples.
ASTM 1412Separation of Ignitable Liquid Residues from Fire Debris Samples by Passive Headspace Concentration with Activated Charcoal.
ASTM E1413Separation and Concentration of Ignitable Liquid Residues from Fire Debris Samples by Dynamic Headspace Concentration
ASTM E2154Separation and Concentration of Ignitable Liquid Residues from Fire Debris Samples by Passive Headspace Concentration with Solid Phase Microextraction (SPME).
ASTM E2451Preserving Ignitable Liquids and Ignitable Liquid Residue Extracts from Fire Debris Samples
ASTM E1618Test Method for Ignitable Liquid Residues in Extracts from Fire Debris Samples by Gas Chromatography-Mass Spectrometry.

[Table] Ignitable Liquid Classification According to GHS Category

The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) classifies flammable liquids based on their flash point and initial boiling point.

CategoryCriteriaClassification
1Flashpoint <23°C and initial boiling point ≤35°CExtremely flammable
2Flashpoint <23°C and initial boiling point >35°CHighly flammable
3Flashpoint ≥23°C and ≤60°CFlammable
4Flashpoint >60°C and ≤ 93°CCombustible

ASTM E1618 Classification Scheme

ASTM E1618 classification scheme includes seven major classes and one non-major class of ignitable liquid compositions. These are:

  1. Gasoline (all brands, including gasohol and E85)
  2. Petroleum Distillates (including De-Aromatized)
  3. Isoparaffinic Products
  4. Aromatic Products
  5. Naphthenic-Paraffinic Products
  6. Normal Alkane Products
  7. Oxygenated Solvents.
  8. Other Miscellaneous Products: That either don’t fall in above classes of falls in more than one.

Sub Classification of ASTM E1618

Except for Gasoline, all other classes can be sub-classified into three more divisions based on the boiling range (because of n-alkanes). These are:

  1. Light product range: n-C4 to n-C9
  2. Medium product range: n-C8 to n-C13
  3. Heavy product range: n-C9 to n-C20+

Composition of Gasoline and Identifiers

  • Alkanes (C4-C12)
  • Small % of alkenes
  • Aromatics: alkylbenzenes, indanes, naphthalenes
  • Oxygenates: ethanol, methyl–tert–butyl ether (MTBE), and ethyl–tert–butyl ether (ETBE)

Components of Gasoline Liquid: Petrol and Diesel With Identiers

TypesCompounds#Identified Markers
Petrol18MTBE, ETBE, benzene, isooctane, heptane, toluene, ethylbenzene, m–xylene, p–xylene, o–xylene, propylbenzene, 3–ethyltoluene, 4–ethyltoluene, 1,3,5–trimethylbenzene, 2–ethyltoluene, 1,2,4–trimethylbenzene, 1,2,3–trimethylbenzene, naphthalene
Diesel14farnesane, tetradecane, pentadecane, hexadecane, norpristane, octadecane, phytane, nonadecane, eicosane, docosane, methyl palmitate, methyl linoleate, methyl oleate, methyl stearate
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