Track 6 of 7
Safety, regulation and environment
How LNG behaves when it escapes, the codes and bodies that govern ships and terminals, and the honest version of the emissions argument including methane slip and upstream leakage.
LNG does not burn as a liquid and does not explode in the open the way a vapour cloud of a heavier hydrocarbon can. What it does is spill, spread, boil, and form a cold vapour cloud that is briefly heavier than air and flammable within a range of concentrations. Understanding that sequence is what terminal siting, exclusion zones and emergency shutdown design are all built around.
The regulatory picture is unusual in that a single international code governs the ships, and an industry body’s guidance is treated as the practical standard alongside it. Terminals, by contrast, are regulated nationally and vary enormously.
The environmental question is genuinely contested and the honest answer is uncomfortable: the combustion arithmetic favours gas over coal, and the upstream methane arithmetic can erase that advantage entirely depending on leakage rates that are poorly measured. This track sets out both sides with the numbers.
7 modules
All written.
- 01Why LNG behaves the way it does in an incident
An LNG spill boils rapidly on contact with warmer surroundings, forms a cold vapour cloud that is initially denser than air, and becomes flammable only where that vapour has diluted into a narrow concentration band.
- 02Rapid phase transition, pool fires and vapour dispersion
A rapid phase transition is a physical explosion caused by LNG vaporising almost instantaneously on contact with water, with no combustion involved, distinct from a pool fire, which is a fire burning above a spreading pool of spilled LNG.
- 03The IGC Code and what SIGTTO does
The IGC Code is the International Maritime Organization's mandatory code for ships carrying liquefied gases in bulk, and SIGTTO is the industry association whose operational guidance is treated as the practical standard alongside it.
- 04Terminal siting and exclusion zones
An exclusion zone is the area around an LNG facility within which development is restricted, calculated from thermal radiation and vapour dispersion modelling of the credible worst-case spill scenarios.
- 05Methane slip and the emissions argument
Methane slip is unburned methane passing through an engine into the exhaust, and it matters disproportionately for climate impact because methane traps far more heat than the carbon dioxide it would have become.
- 06Lifecycle emissions: the honest version
Lifecycle emissions accounting sums greenhouse gas output across production, processing, liquefaction, shipping and regasification through to final combustion, and estimates vary widely mainly because upstream methane leakage is poorly measured.
- 07LNG and maritime chokepoints
A maritime chokepoint is a narrow strait or canal that a large share of seaborne trade must pass through, and LNG exposure to them depends entirely on which exporting region supplies which importing market.
Vocabulary for this track
11 terms, defined in full in the glossary.