Light Petroleum Distillate (LPD)
Definition
The ASTM E1618 ignitable liquid class covering C4-C9 aliphatic products (charcoal lighter fluid, camping fuel, some paint thinners). The class most frequently subject to false-positive identification due to overlap with polyethylene pyrolysis products.
- Standard
- ASTM E1618 ignitable liquid class
- Carbon range
- C4 to C9 aliphatic
- Examples
- Charcoal lighter fluid, camping fuel, some paint thinners
- Key risk
- False positives from polyethylene pyrolysis products
Common questions
Why is the LPD class especially prone to false-positive identification?+
When common plastics like polyethylene burn, their pyrolysis breaks down into aliphatic hydrocarbons that fall in a similar carbon range and chromatographic pattern to genuine light petroleum distillates, so an analyst can mistake melted plastic residue for an ignitable liquid unless the full pattern is carefully evaluated.
How do analysts guard against mistaking pyrolysis products for LPD?+
ASTM E1618 interpretation relies on evaluating the complete chromatographic pattern, including the relative distribution of compounds and diagnostic ratios, rather than any single peak, since pyrolysis-derived hydrocarbons rarely reproduce the full characteristic pattern of a genuine petroleum product.
Related terms
- ASTM E1618
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