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1 LNG SAFETY REPORT “Gas Tanker accidents, although less probable than the accidents with oil tankers, can cause so-called flameless explosions. It happens due to the rapid evaporation of pieces of ice and as clouds followed by combustion and explosions. In 1980, three out of seven accidents of the vessels transporting liquefied gas caused such kinds of explosions. Such explosions can destroy everything alive in areas of up to 400 km 2 [over 150 sq. miles]{Voloshin, 1989, in Russian}.” Quote from Stanislav Patin, 1999 Environmental Impact of the Offshore Oil and Gas Industry Ecomonitor Publishing, Eastport NY The Safety of Liquefied Natural Gas transport raises several disturbing questions. Unfortunately the gas industry’s efforts to provide public assurances have been incomplete and less than candid. From the LNG industry’s own fact sheet: 1. HAVE THERE BEEN ANY SERIOUS LNG ACCIDENTS? First, one must remember that LNG is a form of energy and must be respected as such. Today LNG is transported and stored as safely as any other liquid fuel. Before the storage of cryogenic liquids was fully understood, however, there was a serious incident involving LNG in Cleveland, Ohio in 1944. This incident virtually stopped all development of the LNG industry for 20 years. The race to the Moon led to a much better understanding of cryogenics and cryogenic storage with the expanded use of liquid hydrogen (-423°F) and liquid oxygen (-296°F). LNG technology grew from NASA's advancement. In addition to Cleveland, there have two other U.S. incidents sometimes attributed to LNG. A construction accident on Staten Island in 1973 has been cited by some parties as an "LNG accident" because the construction crew was working inside an (empty, warm) LNG tank. In another case, the failure of an electrical seal on an LNG pump in 1979 permitted gas (not LNG) to enter an enclosed building. A spark of indeterminate origin

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LNG SAFETY REPORT

“Gas Tanker accidents, although less probable than the accidents with oil tankers, can

cause so-called flameless explosions. It happens due to the rapid evaporation of pieces

of ice and as clouds followed by combustion and explosions. In 1980, three out of seven

accidents of the vessels transporting liquefied gas caused such kinds of explosions. Such

explosions can destroy everything alive in areas of up to 400 km2 [over 150 sq.

miles]{Voloshin, 1989, in Russian}.”

Quote from Stanislav Patin, 1999

Environmental Impact of the Offshore Oil and Gas Industry

Ecomonitor Publishing, Eastport NY

The Safety of Liquefied Natural Gas transport raises several disturbing

questions. Unfortunately the gas industry’s efforts to provide public

assurances have been incomplete and less than candid.

From the LNG industry’s own fact sheet:

1. HAVE THERE BEEN ANY SERIOUS LNG ACCIDENTS?

First, one must remember that LNG is a form of energy and must be respected as such.

Today LNG is transported and stored as safely as any other liquid fuel. Before the storage

of cryogenic liquids was fully understood, however, there was a serious incident

involving LNG in Cleveland, Ohio in 1944. This incident virtually stopped all

development of the LNG industry for 20 years. The race to the Moon led to a much better

understanding of cryogenics and cryogenic storage with the expanded use of liquid

hydrogen (-423°F) and liquid oxygen (-296°F). LNG technology grew from NASA's

advancement.

In addition to Cleveland, there have two other U.S. incidents sometimes attributed to

LNG. A construction accident on Staten Island in 1973 has been cited by some parties as

an "LNG accident" because the construction crew was working inside an (empty, warm)

LNG tank. In another case, the failure of an electrical seal on an LNG pump in 1979

permitted gas (not LNG) to enter an enclosed building. A spark of indeterminate origin

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caused the building to explode. As a result of this incident, the electrical code has been

revised for the design of electrical seals used with all flammable fluids under pressure.

This rather rosy picture of LNG accidents conveniently ignores those

incidents in the U.S. which are frequent and small. These smaller

accidents indicate that release of a large amount of LNG could be

catastrophic for populated areas. One such example occurred near

Boston in 1998; which is detailed in the news story below:

Driver killed as LNG tanker flips; explosion averted

by Shirley Ayers, Editor

WOBURN, Mass. -- The driver of a tanker truck carrying 10,500 gallons

of liquefied natural gas was killed when his vehicle flipped over on busy

Route 128 in Woburn, MA, raking down about 300 ft. of guardrail. Diesel

fuel tanks burst, setting the cab on fire.

The accident happened at about 9:30 p.m. when the Transgas Inc. rig,

which was headed south for Connecticut, collided with a car and

overturned onto the meridian on its side. About one mile of the highway

was closed between Routes 93 and 38 because the gas carried a high

methane content and authorities feared an explosion. According to Woburn

Police Chief Philip Mahoney, some 300 people were evacuated from their

homes and from businesses, restaurants and two hotels. All public schools

in Woburn were closed for the day.

Although the fire did impinge on the tanker, quick action by the Woburn

Fire Department, prevented the natural gas from expanding. Water was

hosed onto the tanker to keep the liquefied natural gas cool. Liquefied

natural gas expands in a ratio of 600 to 1. "In a worst case scenario," said

Woburn Fire Chief Paul Tortolano "if the tank had heated in the fire, it

would have expelled liquid instead of gas. We would have had a BLEVE,

and a very severe fire involving a liquefied flammable gas."

Thomas Kiley, president of the New England Gas Association credited the

design of the tanker with averting a disaster. "These vehicles are very

stringently constructed and they are designed to withstand an accident."

The tank vehicle is built like a large thermos bottle, with a reinforced

aluminum inner tank and a carbon-steel exterior. Pressure relief valves

allow any gas that leaks from the inner tank to blow off without rupturing

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the outer tank.

Fortunately the outer tank did not rupture and no natural gas escaped from

the truck. "Had the LNG gone up, it would have been like a bomb," State

Police Lt. Paul Maloney said. "They estimate that it would have thrown

shrapnel about 2,000 ft. It probably would have created a crater out on the

highway that would have kept the highway closed for days if not weeks."

(Fall, 1998 Volume VIII, No. 1)

The nature of this type of potential exposion is explained in detail

below:

The BLEVE Effect.

The Boiling Liquid Expanding Vapor Explosion (BLEVE) effect depends crucially on a

phase change from liquid to vapor that might occur during a loss of containment.

BLEVE occurs when sealed containers of liquefied gases such as LPG are accidentally

exposed and enveloped by fire. Vapor is generated and internal pressure rapidly rises. At

the same time the container wall temperature rises in the ullage area; wall strength

deteriorated and eventually, even though a pressure relief valve may be operating, the

stress impaired by the increased pressure exceeds the reduced strength of the wall. The

container ruptures and superheated liquid is released, expands and vaporizes in seconds

resulting in catastrophic damage from the spread of ignited vapors.

Just such a catastrophe occurred in Australia in 1994 as documented in

this notice from the Australian Maritime Safety Authority.

9/1994

TECHNOLOGY RELATED ACCIDENTS

Modern ships in Australia are highly automated and have cargo

control systems of varying degrees of sophistication. These

systems, although appearing simple to use, can be quite complex

and require officers engaged in cargo handling duties to develop a

thorough understanding of the manner in which the system works.

A number of accidents have recently occurred as a result of failures

in operational procedures on ships with automated cargo control

systems. These accidents are essentially the result of the following

systemic failures:

Alarms accepted but not cancelled:

- in some systems this results in the disabling of audible alarm

indicators, future alarm conditions going unnoticed.

Reliance on remote digital read outs:

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- if gauges stick or sensors malfunction, the absence of on-site

checking, particularly during topping-off operations on tankers,

inevitably leads to problems such as over-filling or

over-pressurising of cargo spaces.

Deviation from set procedures:

- many systems require actuating events to occur in strict

sequence; variation from this often leads to unforeseen effects,

such as the wrong set of valves being opened or closed, or safety

interlocks being by-passed.

Erroneous assumptions made from system indicators:

- in one (non marine) instance, an operator pumping LNG noticed a

large pressure drop in the system, assumed it was caused by an

upsurge in demand and increased the pumping rate. In reality, the

pipeline had ruptured and the explosion of the resultant massive

vapour cloud killed 400.

P McGrath

Chief Executive

Australian Maritime Safety Authority

PO Box 1108 BELCONNEN ACT 2616

June 1994

File: M94/608

Copyright: AMSA

Before we look at other safety considerations we need to understand

more about the nature of LNG and its transport. Again the industry’s

own fact sheet is the principle source of information.

LNG Fact Sheet

WHAT IS IT?

When natural gas is cooled to a temperature of approximately -260°F at atmospheric

pressure it condenses to a liquid called liquefied natural gas (LNG). One volume of this

liquid takes up about 1/600th the volume of natural gas at a stove burner tip. LNG weighs

less than one-half that of water, actually about 45% as much. LNG is odorless, colorless,

non-corrosive, and non-toxic. When vaporized it burns only in concentrations of 5% to

15% when mixed with air. Neither LNG, nor its vapor, can explode in an unconfined

environment.

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COMPOSITION

Natural gas is composed primarily of methane (typically, at least 90%), but may also

contain ethane, propane and heavier hydrocarbons. Small quantities of nitrogen, oxygen,

carbon dioxide, sulfur compounds, and water may also be found in "pipeline" natural gas.

The liquefaction process removes the oxygen, carbon dioxide, sulfur compounds, and

water. The process can also be designed to purify the LNG to almost 100% methane.

HOW IS IT STORED?

LNG tanks are always of double-wall construction with extremely efficient insulation

between the walls. Large tanks are low aspect ratio (height to width) and cylindrical in

design with a domed roof. Storage pressures in these tanks are very low, less than 5 psig.

Smaller quantities, 70,000 gallons and less, are stored in horizontal or vertical, vacuum-

jacketed, pressure vessels. These tanks may be at pressures any where from less than 5

psig to over 250 psig. LNG must be maintained cold (at least below -117°F) to remain a

liquid, independent of pressure.

HOW IS IT KEPT COLD?

The insulation, as efficient as it is, will not keep the temperature of LNG cold by itself.

LNG is stored as a "boiling cryogen," that is, it is a very cold liquid at its boiling point for

the pressure it is being stored. Stored LNG is analogous to boiling water, only 470°

colder. The temperature of boiling water (212°F) does not change, even with increased

heat, as it is cooled by evaporation (steam generation). In much the same way, LNG will

stay at near constant temperature if kept at constant pressure. This phenomenon is called

"autorefrigeration". As long as the steam (LNG vapor boil off) is allowed to leave the tea

kettle (tank), the temperature will remain constant.

If the vapor is not drawn off, then the pressure and temperature inside the vessel will rise.

However, even at 100 psig, the LNG temperature will still be only about -200°F.

The following provides a brief history of U.S. LNG incidents.

Cleveland, 1944:

LNG is not a "new" industry. Earliest patents involving cryogenic liquids date back into

the mid-1800's. The first patent directly for LNG was awarded in 1914. In 1939 the first

commercial LNG peak-shaving plant was built in West Virginia. A second facility was

built in Cleveland in 1941 by the East Ohio Gas Company.

The East Ohio Gas Company peak-shaving plant was run without incident until 1944,

when it was decided to add a much larger new tank. Stainless steel alloys were scarce as

this was during World War II. The new tank was built with a low-nickel content (3.5%).

The tank was placed in service and shortly after failed, spilling its unconfined contents

into the street and storm sewer system. A disastrous fire resulted killing 128 people. This

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accident set back the embryonic LNG industry substantially. The conclusion of the

investigating body, the U.S. Bureau of Mines, was that the concept of liquefying and

storing LNG was valid if "proper precautions were observed," so says "Report on the

Investigation of the Fire at the Liquefaction, Storage, and Regasification Plant of the East

Ohio Gas Co., Cleveland, Ohio, October 20, 1944," U.S. Bureau of Mines, February,

1946.

Staten Island, 1973:

Those "proper precautions" are common place in all of the LNG facilities built and

placed in service after the Cleveland accident. It wasn't until the late 1960's that gas

companies started experiencing supply shortages during periods of severe cold in the

winter. Between the mid-1960's and mid-1970's more than 60 LNG facilities were built in

the United States. (Today there are nearly 100.) These peak-shaving plants have proved

to be economically successful with an excellent safety record. There was, however, one

construction accident that has at times been inappropriately attributed to LNG -- the

Texas Eastern Transmission Corporation (TETCO) tank roof collapse.

An LNG tank at the Staten Island TETCO facility that had been in service for over three

years was taken out of service in order to make an internal tank repair. The tank was

warmed up, purged of the remaining combustible gases with inert nitrogen and then

placed under fresh recirculating air. A construction crew entered the tank in April of

1972. Ten months later, in February of 1973, the polyurethane insulation foam inside the

tank was accidentally ignited. The rapid rise in temperature caused a corresponding raise

in pressure. The pressure increase was so fast that the concrete dome on the tank lifted

and collapsed down inside the tank killing the 37 construction workers inside the tank.

The accident was clearly a construction accident and not an "LNG accident," according to

"Report of Texas Eastern LNG Tank Fatal Fire and Roof Collapse, February 10, 1973,"

Fire Department of the City of New York, July, 1973.

Cove Point, 1979:

The Cove Point Terminal was under construction at the time of the Staten Island

accident. No specific changes were made to the design of the facility as the TETCO tanks

were of a significantly different insulation and tank design. Cove Point was placed into

service with LNG in the Spring of 1978. By the Fall of 1979, Cove Point had unloaded

over 80 LNG ships. On October 6, 1979, anisolated incident occurred at the Cove Point

that lead to three major design code changes.

Around 3:00 AM on October 6, 1979, an explosion occurred within an electrical

substation at Cove Point. LNG leaked through an inadequately tightened LNG pump

electrical penetration seal, vaporized, passed through 200 feet of underground electrical

conduit, and entered the substation. Since natural gas was never expected in this building,

there were no gas detectors installed in the building. The natural gas-air mixture was

ignited by the normal arcing contacts of a circuit breaker resulting in an explosion. The

explosion killed one operator in the building, seriously injured a second and caused about

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$3 million in damages. This was an isolated accident caused by a very specific set of

circumstances. The National Transportation Safety Board found that the Cove Point

Terminal was designed and constructed in conformance with all appropriate regulations

and codes. It further concluded that it is unlikely that any pump seal, regardless of the

liquid being pumped, could be designed, fabricated, or installed to completely preclude

the possibility of leakage. With that conclusion in mind, code changes were made

pertaining to the equipment and systems downstream of the pump seal. Before the Cove

Point Terminal was restarted after the accident, all pump seal systems were modified to

meet the new codes and gas detection added to all buildings. This is reported in

"Columbia LNG Corporation Explosion and Fire; Cove Point, MD; October 6, 1979"

National Transportation Safety Board report NTSB-PAR-80-2, April 16, 1980

The world-wide LNG industry has compiled an enviable safety record based on any

industrial safety standard. There has not been a death or serious accident involving LNG

in the United States since the Cove Point accident.

When Radio Island North Carolina was targeted for a potential LNG

Loading Facility they responded with the following safety concerns.

Risks to Public Safety and Property

According to the Federal Energy Regulatory Commission the major safety concerns related to LNG are: The spillage of the entire contents of a full LNG storage tank that can ignite creating a

large unusually hot fire that produces thermal radiation. This intense heat causes severe burns in as little as 3 seconds; spontaneous combustion of clothing and wood; and the loss of structural integrity in metal.

An LNG tank spill can also produce a flammable vapor plume. The danger zone can

extend to a radius of up to approximately 4,000 ft. in diameter, creating the potential for serious personal injury and property damage or destruction.

Another major safety concern is an LNG tanker spill on the water. The hazard from such

an accident is the creation of a flammable vapor plume that can travel up to two miles creating fire risk for everything in its path.

According to the U.S. Department of Transportation, LNG can also explode in confined

spaces. The Department warns that spills on water are particularly dangerous because the vapors can travel into sewers or other confined spaces where they might be ignited and explode putting public safety and property at extreme risk.

It is apparent that FERC is either not aware of or chooses to ignore the

LNG incidents in Russia which resulted in the loss of at least three LNG

tankers.

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The Department of Transportation was much more thorough in their

examination of risks related to the LNG industry.

This document is disseminated under the sponsorship of the Department

of Transportation in the interest of information exchange.

Clean Air Program: Summary Assessment of the Safety, Health,

Environmental and System Risks of Alternative Fuel

LNG - Important hazardous properties and hazards for LNG include:

o Flammability hazard - fire or explosion from ignition of leaks

of fuel. Non-odorized fuel gas increases the hazard. Note

that the design base for cryogenic fuel system components is

still relatively small.

o Toxicity hazard - asphyxiation from exposure to non-odorized

fuel gas. High pressure hazard - while LNG storage pressures

are not as high as those for CNG, they are still significant.

Also, trapped liquid fuel can produce extremely high pressures

upon warming and vaporization.

o Cryogenic hazards - LNG presents several hazards associated

with the cryogenic property of the fuel:

Personal injury may occur from exposure to cold fuel or

fuel vapors. This is especially true if proper personal

protective gear is not worn.

Structural failure can occur due to stress from

contraction of structural members exposed to cold fuel or

fuel vapors.

Structural failure can also occur due to embrittlement of

materials exposed to cold fuel or fuel vapors.

The third development, which adds to the complexity of alternative

fuel use, is the recognition that more hazards must be considered

than the traditional "Will it burn or explode?" examination of fuel

issues. For example, LNG has the potential to cause blindness if

splashed in the face.

3.3.4 Liquefied Natural Gas

3.3.4.1 General Description

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Liquefied natural gas (LNG) is produced by cooling natural gas and

purifying it to a desired methane content. The typical methane

content is approximately 95% for the conventional LNG produced at a

peak shaving plant. Peak shaving involves the liquefaction of

natural gas by utility companies during periods of low gas demand

(summer) with subsequent regasification during peak demand (winter).

It is relatively easy to remove the non-methane constituents of

natural gas during liquefaction. Therefore, it has been possible

for LNG suppliers to provide a highly purified form of LNG known as

Refrigerated Liquid Methane (RLM) which is approximately 99%

methane.

The primary advantage of LNG compared to CNG is that it can be

stored at a relatively low pressure (20 to 150 psi) at about one-

third the volume and one-third the weight of an equivalent CNG

storage tank system. The big disadvantage is the need to deal with

the storage and handling of a cryogenic (-160o~C, -260

o~F) fluid

through the entire process of bulk transport and transfer to fleet

storage.

3.3.4.2 Safety Issues

(a) General Properties Affecting Fire Hazards

Even though the end product of the use of CNG and LNG for vehicular

applications is essentially the same, the general properties

affecting safety are quite different. On one hand, LNG is a more

refined and consistent product with none of the problems associated

with corrosive effects on tank storage associated with water vapor

and other contaminants. On the other, the cryogenic temperature

makes it extremely difficult or impossible to add an odorant.

Therefore, with no natural odor of its own, there is no way for

personnel to detect leaks unless the leak is sufficiently large to

create a visible condensation cloud or localized frost formation.

It is essential that methane gas detectors be placed in any area

where LNG is being transferred or stored.

The cryogenic temperature associated with LNG systems creates a

number of generalized safety considerations for bulk transfer and

storage. Most importantly, LNG is a fuel that requires intensive

monitoring and control because of the constant heating of the fuel

which takes place due to the extreme temperature differential

between ambient and LNG fuel temperatures. Even with highly

insulated tanks, there will always be a continuous build up of

internal pressure and a need to eventually use the fuel vapor or

safely vent it to the atmosphere. When transferring LNG,

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considerable care has to be taken to cool down the transfer lines in

order to avoid excessive amounts of vapor from being formed.

The constant vaporization of the fuel also has an interesting effect

on the properties of the fuel, unless it is a highly purified form

of LNG, i.e., RLM. The methane in the fuel will boil off before

some of the other hydrocarbon components such as propane and butane.

Therefore, if LNG is stored over an extensive period of time without

withdrawal and replenishment the methane content will continuously

decrease and the actual physical characteristics of the fuel will change to

some extent. This is known as "weathering" of the fuel. 7

Another consideration is that under low temperatures, many materials

undergo changes in their strength characteristics making them

potentially unsafe for their intended use. For example, materials

such as carbon steel lose ductility at low temperature, and

materials such as rubber and some plastics have a drastically

reduced ductility and impact strength such that they will shatter

when dropped.

(b) Fire Hazards During Transport

An explosion of an LNG container is a highly unlikely event that is

possible only if the pressure relief equipment or system fails

completely or if there is some combination of an unusually high

vaporization rate (due to loss of insulation) and some obstruction

of the venting and pressure relief system preventing adequate vapor

flow from the inner pressure vessel with a resultant pressure build

up. If the pressure builds up to the point where the vessel bursts,

the resulting explosion is known as a BLEVE (boiling liquid

expanding vapor explosion) with the container pieces propelled

outward at a very high velocity.' This is a highly unlikely event

due to the extensive requirements for pressure relief including

pressure relief valves and burst discs that are built into the

design codes. (There have been no reports in the literature reviewed

of any BLEVE occurring with LNG.)

Note: This is only true if you ignore the incidents in Australia and

Russia!

In the event that the LNG vessel is ruptured in a transport accident

and the LNG is spilled, there will be a high probability of a fire

because a flammable natural gas vapor/air mixture will be formed

immediately in the vicinity of the LNG pool. In an accident

situation, there is a high likelihood of ignition sources due to

either electrical sparking, hot surface, or possibly a fuel fire

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created from the tanker truck engine fuel or other vehicles involved

in the accident. The vapor cloud from an LNG pool will be denser

than the ambient air; therefore, it will tend to flow along the

ground surface, dispersed by any prevailing winds.

When spilled along the ground or any other warm surface, LNG boils

quickly and vaporizes. A high volume spill will cause a pool of LNG

to accumulate and the boiling rate will decrease from an initial

high value to a low value as the ground under the pool cools. The

heat release rate from an LNG pool fire will be approximately 60%

greater than that of a gasoline pool fire of equivalent size.

(c) Fire Hazards During Transfer to Fleet Storage

The complexity of the fuel transfer arrangement creates the potential

for leaks and spills through human error and equipment failure.

One of the particular concerns is that the fuel transfer

equipment goes through a continuous cycle of cool down to cryogenic

temperatures and warm up to ambient temperature. This type of

thermal cooling can create additional stresses on equipment and

sealing devices which could result in decreased reliability over

time.

(d) Fire Hazards During Fleet Storage

One of the major provisions at any LNG storage facility is the

requirement to provide an impounding area surrounding the container

to minimize the possibility of accidental discharge

of LNG from endangering adjoining property on important process

equipment and structure, or reaching waterways. This requirement

ensures that any size spill at a fleet storage facility will be

fully contained and the risk of any fire damage will be minimized.

(e) Other Hazards

LNG has a unique safety hazard among the alternative motor fuels (AMFs)

because of the potential exposure of personnel to cryogenic temperatures.

Workers can receive cryogenic burns from direct body contact

with cryogenic liquids, metals, and cold gas. Exposure to LNG or

direct contact with metal at cryogenic temperatures can

damage skin tissue more rapidly than when exposed to vapor. It is

also possible for personnel to move away from the cold gas before

injury.

The risk of cryogenic burns through accidental exposure can be

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reduced by the use of appropriate protective clothing. Depending

upon the risk of exposure, this protection can range from loose

fitting fire resistant gloves and full face shields to special extra

protection multi-layer clothing.

Another unusual hazard associated with aged LNG will arise in the

unlikely event that there is a large spill of LNG onto a body of

water. This could occur in an accident situation involving an LNG

transport vehicle container rupture and spill into an adjacent water

body. The hazard is known as a rapid-phase transition (RPT) - in

this case a rapid transformation from the liquid phase to vapor. If

significant vaporization occurs in a short time period, the process

can, and usually does, resemble an explosion.'

The RPT "explosion" phenomenon for LNG on water has been observed in

a number of situations and has been studied extensively in both

laboratory and large scale tests. The temperature of the water and

the actual composition of the LNG are important factors in

determining whether an RPT will take place.

3.3.4.3 Health Issues

The principal constituents of natural gas, methane, ethane, and

propane, are not considered to be toxic. The American Conference of

Governmental Industrial Hygienists (ACGIH) considers those gases as

simple asphyxiants, which are a health risk simply because they can

displace oxygen in a closed environment. The Occupational Safety

and Health Administration (OSHA) has set a time-weighted average

(TWA) personal exposure limit (PEL) of 1,000 ppm for propane. A

number of the minor constituents of natural gas have ACGIH listed

threshold limit values (TLVs), including butane - 800 ppm, pentane -

600 ppm, hexane - 50 ppm, and heptane - 400 ppm. The effective TLV

for an average natural gas composition, considering all of these

limits, is about 10,500 PPM.3~

Unlike CNG, LNG cannot be odorized; therefore, there is some concern

about the ability of personnel to detect TLV concentrations. This

is another reason to ensure that methane detectors are in place

wherever personnel may be exposed.

The following tables from the Department of Transportation show that

handling of LNG is more dangerous than dealing with gasoline or diesel

fuels. This is contrary to what is asserted in the LNG industry fact

sheet.

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TABLE 3-1. RELATIVE POTENTIAL FOR SPILLS DURING TRANSPORT

RELATIVE SPILL POTENTIAL

(COMPARED TO GASOLINE/DIESEL TRUCK SPILL)

REASON

LNG Lower Double walled cryogenic transport tank

TABLE 3-2 RELATIVE POTENTIAL FOR LEAKS DURING TRANSPORT

RELATIVE LEAK POTENTIAL

(COMPARED TO GASOLINE/DIESEL TANKER TRUCK)

REASON

LNG Higher 300 F temperature differentials and

pressures up to 150 psi

TABLE 3-3. RELATIVE POTENTIAL FOR SPILLS DURING UNLOADING

RELATIVE SPILL POTENTIAL

(COMPARED TO GASOLINE/DIESEL TRUCK SPILL)

REASON

LNG Higher Combination of temperature

cycling/mechanical failure

and complexity of transfer

process

TABLE 3-4. RELATIVE POTENTIAL FOR LEAKS DURING UNLOADING

RELATIVE LEAK POTENTIAL

(COMPARED TO GASOLINE/ DIESEL TANKER TRUCK)

REASON

LNG Higher Temperature differential

and moderate pressure

TABLE 3-5. RELATIVE POTENTIAL FOR SPILLS DURING FLEET STORAGE

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RELATIVE LEAK POTENTIAL

(COMPARED TO GASOLINE/ DIESEL TRUCK)

REASON

LNG Higher Temperature differentials

LNG Transport and utilization represents a significant risk for a

catastrophe to occur in Boston and vicinity either through

equipment/materials failure, terrorist action or human error. Boston is

one of the few ports which permits unloading of these hazardous

substances in close proximity to major population centers. The details

of safety concerns have been well documented in this and other regions.

Given the additional information on LNG disasters in Australia and

Russia, it is now incumbent on the city to stop or significantly delay

these dangerous shipments until such time that a thorough investigation

can be conducted of global LNG safety incidents.

David Lincoln

GFWA 2001