Safety & Security
What is LNG
LNG is odorless, colorless, non-corrosive, and non-toxic. Liquefied Natural Gas (LNG) is not flammable. One could even safely extinguish a cigarette in LNG and would be at no risk. When LNG is warmed it becomes natural gas again with the same flammable properties as the natural gas burned to heat homes all across the U.S.
When cold LNG mixes with warmer air, the water in the air condenses to become a visible vapor cloud. As it warms, the natural gas becomes lighter than air and rises. The LNG vapor is only flammable if the range of natural gas in the air within 5-15 percent. Less than five percent natural gas in air is not enough natural gas in the air to burn. More than 15 percent natural gas in air, there is too much gas in the air and not enough oxygen for it to burn.
LNG transport has a superior safety record
The LNG transport ships are large, double-hulled vessels lined with heavy steel. On the very rare occasions that one has been involved in any kind of accident, there have never been any environmental consequences or cargo fire.
Construction of LNG vessels
Guidelines set by local, state, and national agencies ensure and require the safe transportation and storage of LNG throughout the country. LNG vessels have been improved over the past half a century with stronger metals to ensure minimized risks of breaking.
The ships will employ both double containment of their contents and double hulls, ensuring a very low risk of any spills or accidents. This full containment ensures that if leaks or spills do occur, the LNG will be contained and isolated. The double hulls ensure a very low risk that any breach would even reach the hull containment tanks. The vessels are designed with a double hull to ensure minimization of leakage in the event of a collision or grounding, as well as separate ballast.
Safeguard systems
LNG facilities have extensive, state-of-the-art warning systems, including gas detectors, ultraviolet or infrared fire detectors, smoke or combustion product detectors, low temperature detectors, and detectors to monitor LNG levels and vapor pressures. Codes and standards from state, national, and international agencies and institutions insure the chances of any releases are very small, and if there are releases, the volume of the release is minimal. In addition to warning systems, LNG facilities have automated firefighting systems, including foam, dry chemical, or water dispersal and automatic shutdown systems.
U.S. regulations require protection distances for LNG storage, and have strict guidelines for activities within these protection distances. The proposed LNG import facility will have no exemption from these codes, and every effort will be made to ensure the safety of the facility’s environment, employees, and neighbors. While the exact distances for this particular facility are not yet known, the distance is expected to be approximately 1,000 feet, and all evaluations and tests will ensurein the unlikely event of an accident—the safety of everyone surrounding the facility and the vessels.
The United States Coast Guard (USCG) uses “zones of concern,” or distances from ships within which they pay particular attention. Depending on the types of structures and population densities within the safety zone, the USCG requires various strategies to ensure the safety of the ship and the surrounding areas.
The USCG also uses “safety zones” around the ships to ensure the safety of the existing boats using the waters and the security of the ships.These safety zones, which vary from terminal to terminal and range from several feet to up to a mile, do not necessarily exclude other ships or activities inthe waters.
Common Questions
How safe are the LNG storage tanks?
LNG facility safety requirements, along with the industry standards and best practices, are designed to ensure safety and security of all LNG facilities. Storage tanks and other equipment must be made of suitable materials with the proper engineering design. There are secondary containment systems - designed to hold more than the storage tank - to ensure isolation and control of LNG if a leak occurs. A tertiary containment system often surrounds storage tanks, ensuring LNG does not leak into drainage systems. There are also safeguard systems, such as gas, liquid and fire detectors to identify any failures as well as remote and automatic shut off systems to minimize leaks and spills. Finally, LNG facility designs are required to maintain separation distances to separate land-based facilities from communities and other public areas.
What is the likelihood of explosion at the storage tanks?
An explosion is highly unlikely because LNG is stored under atmospheric pressure. LNG is never flammable and natural gas cannot explode if it is not confined under pressure. Immediately after being released into the surrounding air, LNG starts to warm up and convert into a gas. Since initially the gas is colder and heavier than the surrounding air, it creates an icy fog - freezing the moisture in the air, as when a freezer door is opened. However, as the gas warms up, it blends with the air and begins to disperse and rise upward. The cloud could ignite close to the ground only if there is something to ignite it during a narrow window when the right mixture of gas and air exists for combustion. If released on water, LNG floats and vaporizes, leaving no residue.
Are LNG tankers and storage facilities likely terrorist targets?
All parts of our critical energy infrastructure have been reassessed since the terrorist attacks of September 11, 2001. Security consciousness throughout the United States is heightened. Shippers have redoubled their already-stringent efforts to ensure security of transportation and the safety of terminals. There is no indication that LNG facilities or ships are more likely terrorist targets than other cargo ships or higher visibility political targets such as federal or state landmarks, public gatherings or bridges and tunnels. Nonetheless, LNG suppliers work closely with U.S. agencies charged with national security, and many developers contract with international experts who test their plans, procedures, people, and training to ensure they are sound. First, stringent access controls exist at both the point of origin and the point of destination. Both the liquefaction and re-gasification terminals have gated security access and continuous surveillance monitoring. Next, highly specialized, well-trained personnel serve as crewmembers. Before an LNG ship enters U.S. waters, the immigration service validates the crew. There is a buffer zone required between tankers and other traffic, and tugboats control the direction of tankers as they approach a terminal. Oversight is handled by the U.S. Coast Guard and host port authority pilots. Finally, the Coast Guard boards ships before they enter U.S. waters if it deems the ship a security risk.
