- Liquefied Natural Gas (LNG) has an excellent safety record in the shipping industry
- LNG is not flammable. In fact, LNG itself does not burn because it does not contain oxygen, which is needed for combustion. One could safely extinguish a cigarette in LNG and there would be no risk of fire.
- LNG is not explosive. It cannot explode because the liquid state prevents it from mixing with sufficient oxygen.
- If LNG is released into the air, the liquid immediately warms up and converts back to a gas. Initially, the gas is colder and heavier than the air, so it freezes any water vapor in the air. This can temporarily create an icy fog similar to the vapor that escapes when you open your freezer door in warm weather. As the gas continues to warm, it dissipates and rises harmlessly into the air.
- LNG is odorless, colourless, non-corrosive and non-toxic.
- LNG is not stored or transported under pressure. In fact, LNG will be stored at Grassy Point in new tanks at very low pressure – at about 1 to 3 psi (pounds per square inch). In comparison, the tires on your car are inflated to 28 to 30 psi.
LNG Vessel Safety
The safety record of LNG ships far exceeds any other sector of the shipping industry. LNG has been shipped globally for over 60 years and has a an impressive 40-year record of safe operations in North America. LNG carriers have made more than 40,000 trips covering more than 96 million km (60 million miles) without a major incident, either in port or at sea. Over the past four decades, there have been no collisions, fires, explosions or hull failures resulting in a loss of containment for LNG ships.
LNG is transported in double-hulled ships designed to prevent leakage or rupture in an accident. LNG is stored in either double membrane containment systems made of special materials and located within the ship’s inner hull or special 3/4-inch-thick spherical tanks. For membrane containment systems, a secondary containment system surrounds the primary container. The insulation space between the two has sensing equipment to detect even the smallest presence of methane (the main component of natural gas), possibly indicating a leak of LNG.
The few incidents that have occurred on LNG ships are typical of the incidents on all types of ships (i.e., not related to either the LNG cargo or the fact that the ship was an LNG carrier). Incidents have included minor piping leakage (non-LNG) and an occasional venting of a tank. According to the U.S. Department of Energy, over the life of the industry, eight marine incidents worldwide have resulted in accidental spillage of LNG. In these cases, only minor hull damage occurred and there were no cargo fires. Seven additional marine-related incidents have occurred with no significant cargo loss. No explosions or fatalities have ever occurred.