At Dominion, safety is our way of doing business. Dominion is committed to safe operations, safe facilities, and safety-minded employees. As part of our ongoing safety focus, we meet with emergency workers and those who live near our facilities to keep them informed about LNG, natural gas and Dominion.
LNG is nontoxic, odorless, nonexplosive and nonflammable in its liquid state. In fact, it will burn only after it has been re-gasified and mixed in the proper proportion with air. Natural gas burns only within the narrow range of a 5 to 15 percent gas-to-air mixture. Liquefied natural gas has about 45 percent the density of water, so if spilled onto a waterway, it will stay on top of the water until it evaporates into the atmosphere.
Since commercial LNG transport began in 1959, LNG has been safely transported, stored and delivered to densely populated cities in the United States, Europe and Japan. During that time, more than 33,000 LNG carrier voyages, covering more than 60 million miles, have arrived safely without a significant accident or safety problem, either in port or on the high seas. Since reopening the Cove Point terminal in 2003, Dominion has maintained a safe and secure facility.
LNG ships are well-built, robust vessels with a double-hull design built to withstand the low-energy impacts common during harbor and docking operations. They are a common sight throughout much of the world. Japan, for example, receives 96 percent of its natural gas via LNG carriers.
Safety is a core value at Dominion and our top priority each and every day.
LNG Terminals have an exemplary safety record. Their safety is a product of advanced technology, well-trained professionals, a thorough understanding of LNG risks, robust safety systems and procedures, and rigidly adhered-to standards, codes and regulations. In the past 30 years, no death or serious accident involving an LNG terminal has occurred in the United States.
Modern LNG storage tanks, which use 9 percent nickel-steel, have never had a crack failure in their 30-year history. And should there ever be a leak, all tanks are surrounded by embankments large enough to contain the entire contents of the tank.
Beyond this dual containment system required by federal regulations, many modern tanks have two walls – an inner wall of high nickel steel surrounded by a wall of concrete, generally three feet thick. Should the inner steel wall fail, the outer concrete tanks will contain the LNG.
FERC regulations require safety zones around LNG facilities. Setback distances must be great enough so that flammable vapors will not reach the facilities’ property lines and heat radiation from a potential fire will not impact those beyond the facilities’ property line. Sophisticated safety systems add an additional layer of protection.
Sophisticated alarms and multiple back-up safety systems, which include emergency shutdown (ESD) systems, are core components of LNG facilities. ESD systems can identify problems and shut down operations, limiting the amount of LNG that could be released. They are normally linked to automated gas, liquid and fire-detection equipment. There are also detectors for monitoring LNG levels and vapor pressures within storage tanks and closed-circuit television equipment for monitoring all critical locations of LNG facilities.
Facility safety systems combined with special operating procedures, training and equipment maintenance minimize the risk of an accident.
FERC is responsible for approvals regarding siting, operation and expansion of LNG facilities on land, as well as offshore facilities in state waters. The United States Coast Guard (USCG) and Maritime Administration (MARAD) have jurisdiction for siting and operation of LNG facilities in federal waters.
Industry and government standards set specifications for, among other things, concrete and steel used in construction, for valves, pumps, tanks, compressors, refrigeration piping, tank insulation, fire-fighting equipment, and for protection against seismic activity. A review of standards applied to recent LNG projects identifies nearly 30 related to fire safety standards alone.
Compressor stations are equipped with an Emergency Shutdown System that stops engines and isolates and vents compressor piping. The central control system is monitored 24 hours a day, 365 days a year. The control systems monitor gas as it travels through all sections of pipeline.
In addition, compressor stations are subject to standards and regulations of the U.S. Department of Transportation, FERC, Office of Pipeline Safety, National Transportation Safety Board, Federal Emergency Management Agency and state jurisdictional agencies.