The intent of the ILRC database with its associated liquid repository is to provide a FREE searchable resource that allows a laboratory to isolate an ignitable liquid of interest for inclusion into an in-house reference collection. Commercial products are obtained from manufacturers and retailers then repackaged for distribution using the same product name. The database is designed for screening purposes only; it does not replace ASTM requirements for an in-house reference collection. Classification of the ignitable liquids within the database parallels the ASTM E1618-19 and is a consensus from a committee of practicing fire debris analysts.
The Ignitable Liquids Reference Collection (ILRC) Database was developed by the ILRC Committee of the Technical/Scientific Working Group for Fire and Explosives. The ILRC is a compilation of reference materials used by forensic analysts to conduct fire debris analysis. The ILRC consists of a comprehensive set of ignitable liquids and accompanying characterization data used in the analysis of fire debris samples in accordance with the American Society for Testing and Materials (ASTM) E-1618 standard test methods.
How to import the data file into Chemstation
After you download and save the common data format (CDF) file, import the file into Chemstation with the import function.
Best Practices Guide
User comments are welcomed by the ILRC committee, please contact the ILRC committee chair.
Care must be exercised in relating the contents of this database to extractions from fire debris collected in fire scenes. The ignitable liquid samples were prepared under controlled conditions.
Definitions
SRN: the sample reference number identifies each record.
Brand Name: the brand and product name assigned by the manufacturer/distributor.
Hydrocarbon Range: the spread of peaks on the TIC that lie within the hydrocarbon (alkane) ruler.
Predominant ion profile: the most prevalent extracted ion profile.
Major peaks: predominant peaks based on peak height intensity are identified.
Classification: a classification from ASTM E1618-19. Classifications for weathered and biologically degraded samples are from the unaltered (neat) ignitable liquid.
Sub-component class: extended classification for ignitable liquids classified as an oxygenated solvent or miscellaneous. The sub-component class is not a repetition of the primary class, but rather indicates the classification of additional ignitable liquids in the mixture.
Product use: the intended use for which the product is marketed.
Degradation type: the condition of the ignitable liquid as either weathered (evaporated) or biologically degraded.
Date of run: the date analyzed.
Supplemental information: any additional information available regarding the ignitable liquid.
Dataset: a downloadable GC-MS data file in a computable document format (CDF).
Chromatograms: a downloadable document with the total ion chromatogram and extracted ion profiles.
SDS: downloadable safety data sheet of the ignitable liquid.
Classification Criteria
Hydrocarbon range: the hydrocarbon range is based on the predominant profile. In this database the assigned ranges were adopted to provide uniformity where the majority of the profile lies between a lower and a higher carbon range as indicated by the retention time of normal alkanes.
Major peaks: when the highest peak is at 100% relative scale, and any other peaks higher than 80% are considered “major peaks”. The five highest identifiable peaks are the five “major peaks” used in the database. Exceptions are when an identifiable peak less than 80% affects the assignment of classification.
Miscellaneous: these ignitable liquids may be composed of two or more distinct patterns.
Blends: blends are classified as miscellaneous.
1. In HPD, the dominant aromatic compound is approximately 50% or more than the dominant n-alkane compound by peak height.
2. Blends with a heavy component that likely won’t be seen in debris without solvent extraction will be classified as both miscellaneous and by the pattern minus the heavy portion.
3. In MPD, it is not uncommon to see elevated aromatics. The determination of whether an ignitable liquid is a MPD or a blend of MPD and aromatic is subjective and dependent on the analyst, their training, and laboratory procedures.
Oxygenated solvents: one or more of the five major peaks (based on peak height) in the ignitable liquid is an oxygenated compound. It should be noted, if the oxygenated compound is present and is not identified as one of the five major peaks, it will be classified as a miscellaneous product.
Insecticides: insecticides are classified based on the solvent vehicle in the product.
Sample Preparation
Ignitable liquids were prepared for GC-MS analysis by diluting 20 microliters of ignitable liquid in one milliliter of carbon disulfide.
Weathered Ignitable Liquids
A graduated microvial was filled with 10 milliliters of ignitable liquid. The vial was placed into a dry bath where the height of the vial and temperature of the dry bath were adjusted according to the percent volume evaporated. Nitrogen flowed gently above the ignitable liquid and a vacuum pump was used to evaporate the ignitable liquid vapor from the vial into a trap. This was to prevent the vapor from condensing back into the vial. The nitrogen needle and vacuum tubing were cleaned between samples and replaced when needed. Evaporation percentages were 25%, 50%, 75%, 90%, and 95%, corresponding to volumes of 2.5 mL, 5.0 mL, 7.5 mL, 9.0 mL, and 9.5 mL, respectively. During the evaporation process, twenty microliters of ignitable liquid was collected at each of the volume reductions. One milliliter of carbon disulfide was added to the auto sampler vial containing the evaporated ignitable liquid.
Biologically Degraded Ignitable Liquids
Twenty microliters of ignitable liquid was deposited into a quart sized metal paint can with 100 grams of Hyponex brand potting soil purchased from Kmart. Once sealed, the liquid and soil were mixed. After the specified time period (0, 7, 14, or 21 days), a whole activated carbon strip attached to a paperclip and nylon string was suspended into the headspace of the can. The can was placed into a 65 degree Celsius for 16 hours. Once the can was removed from the oven, it cooled down to room temperature. The activated carbon strip was cut in half, and one half was placed into an autosampler vial with 500 microliters of carbon disulfide.
Instrument Parameters
Instrument and Accessories
Prior to 2012
Agilent 6890 gas chromatograph and 5973 mass spectrometer
2012 to present
Agilent 7890B gas chromatograph and 5977E mass spectrometer
Agilent ALS autosampler G2614A
GC Conditions
Column: HP-1 or equivalent
Length: 25 meters
Inner diameter: 0.20 millimeters
Film thickness: 0.5 microns
Carrier gas: helium (ultra high purity)
Flow: constant
Flow rate: 0.8 ml/min
Linear velocity: approximately 36 cm/sec
Split ratio: 50:1
Injection volume: 1 microliter
Pre-injection washes of sample: 2
Pumps: 2
Post-injection wash of solvent A: 10
Post-injection wash of solvent B: 10
Plunger speed: fast
Injection temperature: 250 degrees Celsius
Initial oven temperature: 50 degrees Celsius
Initial hold time: 3 min
Rate: 10 degrees Celsius per minute
Final temperature: 280 degrees Celsius
Final hold time: 4 min
Total run time: 30 min
MS Conditions
Transfer line temperature: 280 degrees Celsius
Acquisition mode: scan
Scan range: 30-350
Scan rate: 2-3 scans/sec; equivalent to 6-10 scans per peak
Solvent delay: 2 min. As of November 2010, there is no solvent delay instead the detector is off between 1.54 and 2.00 minutes.