* Emergency testing order lacks clarity, experts say
* Current crude testing could produce flawed results
By Kristen Hays
NEW ORLEANS, March 3 A U.S. emergency order to
test oil shipped by rail highlights what many industry officials
have long said is a flawed method for testing the volatility of
types of oil that have been involved in several fiery train
derailments in the last year.
U.S. regulators last week took the latest step in an effort
to address public and political outcry over the risks of
shipping potentially volatile oil on mile-long trains across the
United States, issuing an immediate order that all such cargoes
must be tested for a range of qualities.
The order did not specify the frequency or method for such
tests, leading to complaints about how shippers could comply.
Until now, it has been up to shippers themselves to vouch for
their cargo, and to decide what testing, if any, was necessary.
Some industry players say test data could be questionable,
especially if they rely on a decades-old standard that many say
fails to account for a large share of the highly volatile gases
and natural gas liquids (NGLs) that emerge from shale oil fields
like North Dakota's Bakken.
Testing experts at a Crude Oil Quality Association meeting
in New Orleans last week said they were concerned that the order
did not spell out how testing would be conducted, and in
particular whether the decades-old Reid Vapor Pressure (RVP)
test, which has long been viewed as flawed, would be updated.
Harry Giles, former manager of crude oil quality programs
for the U.S. Department of Energy's Strategic Petroleum Reserve
and COQA's former executive director, said current testing
methods may fail to detect all the elements the order said they
Those include the percentage of flammable gases in the
crude, its flash point, or the temperature at which its
compounds can give off enough vapor to ignite in air, the vapor
pressure at 50 degrees Celsius (122 degrees Fahrenheit) and
content of hydrogen sulfide, a highly toxic gas.
"I have reservations about the sampling and the analysis
methods that are likely to be used to achieve that," he said.
The presence of light-end gases such as propane, butane, or
hexane, some of which remain dissolved in Bakken crude but can
"flash off" as vapor under certain conditions, can significantly
raise pressure ratings, and potential volatility, of rail
cargoes, experts say.
It is unclear what impact such tests could have, regardless
of the results. Existing regulations do not use vapor pressure
measurements to determine how crude oil is shipped.
Last week's order already bars shippers from using the
least-dangerous level of classification for oil cargoes, leaving
little leeway for further measures based on what the tests
A month ago regulators fined prominent Bakken producers Hess
Corp, Marathon Oil Corp and Whiting Petroleum
Corp for wrongly classifying crude shipments from North
A string of explosive derailments has put a sharp light on
the safety of the rising oil-train shipments emerging from the
Bakken oil fields, prompting regulators to investigate a number
of possible factors, including use of older, less fortified tank
cars, the labels that shippers use and the oil itself.
Since last summer's Lac-Megantic, Quebec, disaster, in which
a runaway oil train exploded in the town's center, killing 47
people, U.S. regulators have been checking North Dakota oil
shipments to determine whether shippers have correctly labeled
Crude oil is not usually considered a highly flammable
material. But light oil like that produced in the Bakken field,
more than two-thirds of which is transported by rail, contains
the combustible light ends that can catch fire or explode if
sparks fly in a crash.
Data from pipeline operator Capline shows that Bakken crude
has registered a Reid Vapor Pressure of more than 9 lbs per
square inch (psi), versus readings nearer 5 psi for many popular
imported crudes. A newer reading this year showed one sample at
below 6 psi, highlighting the wide variability of Bakken crude.
Testing oil samples to determine their vapor pressure is one
of the main tools that safety regulators and the energy industry
can use to determine the volume of such light-ends inherent in
the oil, and therefore how combustible it may be.
Giles, now a managing principal for liquid petroleum
transport company PetroStorTech LLC, said that in order to get
an accurate reading and preserve light ends, crude samples need
to be put in bottles that are chilled to zero to 1 degree
Celsius (32 to 34 Fahrenheit).
However, he said samples are commonly gathered in unchilled
plastic two-liter bottles, and light ends can vaporize and flash
off before samples even get to a laboratory for testing.
Louis Ory of Intertek, one of the world's leading
quality test groups, said improper sample gathering leads to
"I've seen crude samples analyzed in Dasani bottles. Things
like that will surely affect the quality of the data coming out
of a laboratory," he said at the COQA gathering.
A growing number of firms recommend adopting alternative
testing protocols for light crudes and use of a specialized
container known as a floating piston cylinder designed to
preserve pressurized liquid and gas samples at chilled
temperatures for testing.
However, Giles said they can cost $2,700 each, and may have
to be ordered. "You don't go to the supermarket and buy a case
of floating piston cylinders," he said.
Transport Canada, which regulates fuel shipments, hopes to
soon endorse a device for proving crude oil pressure that will
be "an efficient and scientific method of determining the
volatility of products, such as those shipped by rail," a
It is unclear how many producers in the Bakken region use
the newer methods, such as the cylinders, but both regulators
and some refiners say that tests of any sort have been
infrequent and inadequate.
For refiners, light ends have been more of an operational
challenge than a safety risk, as they often have to be burned
off or split out from crude before refining. Valero Energy Corp
and Delek U.S. Holdings have added "pre-flash"
units to some plants to handle those light ends.
Some refiners discover gassy cargoes after they are tested
upon arrival, according to a presentation last summer by Gary
Weimar of Irving Oil, a private Canadian refiner and a major
buyer of Bakken crude.
Tank cars arrive from suppliers whose "source sampling
program is almost non-existent," he wrote in the June
presentation, days before the Lac-Megantic tragedy. That train
had been destined for Irving's New Brunswick refinery.
Weimar declined further comment.
While flammable gases like propane must travel in special
pressurized vessels due to their volatility, cargoes shipped as
crude oil may travel in standard tank cars regardless of their
In the meantime, testers and their customers are calling for
more clarity on how, when and what to test.
"We'll have to wait and see," said Kesavalu Bagawandoss,
shale oil and gas corporate technical director for Intertek.
"The emergency process is different from actual regulations."
(Reporting by Kristen Hays in New Orleans; Additional reporting
by Patrick Rucker in Washington and Joshua Schneyer in New York;
Editing by Jonathan Leff, Richard Chang, Lisa Shumaker and Paul