# LNG and natural gas (BOG) behaviour **URL:** \ **Category:** LNG\ **Tags:** lng\ **Created:** [February 7, 2023, 8:06pm UTC](https://www.queseas.com/t/lng-and-natural-gas-bog-behaviour/664 "2023-02-07T20:06:41Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Surcouf\_Renard](https://avatars.discourse-cdn.com/v4/letter/s/51bf81/32.png) [@Surcouf\_Renard](https://www.queseas.com/u/Surcouf_Renard)\ **Post date:** [February 7, 2023, 8:06pm UTC](https://www.queseas.com/t/lng-and-natural-gas-bog-behaviour/664/1 "2023-02-07T20:06:41Z")
### How LNG behaves? • is a boiling liquid which, because of its low storage temperatures (-163 to -130°C, depending on pressure), is continuously vaporizing into gas (boil-off gas, or BOG) as it absorbs heat from the environment. • will vaporize and rapidly pressurize a system to bursting point if left trapped between two valves without pressure relief • will rapidly damage ship-quality steels in the area around a spill; rapid cooling reduces the ductility of steel and its ability to support load, which can cause brittle fracture of a vessel’s deck or of a steel component of a quayside • may cause a Rapid Phase Transition (RPT) if it is mixed with water and boils so rapidly that an over-pressure situation occurs; an RPT is effectively a flameless explosion. ### How natural gas (BOG) behaves? • is heavier than air until it warms to -110°C; so, if it leaks, it will initially flow downwards • is flammable at concentrations between 5% and 15% in air • is not odourised and so does not smell like pipeline natural gas • is not itself visible but causes surrounding water vapour to condense, producing a visible white cloud • can lead to a lack of visibility within a vapour cloud • can be cold enough to cause hypothermia, cold burns and frostbite • may replace oxygen within a vapour cloud preventing people from breathing (asphyxiation)