### A Survey of Bakken Crude Oil Characteristics Assemb led

For the U.S. Department of Transportation

Submitted by

American Fuel & Petrochemical Manufacturers

Prepared by

Dangerous Goods Transport Consulting, Inc.

May 14, 20142 

### Table of Contents

Executive Summary: Summary Table on Bakken Crude Oil Characteristics E valuated in AFPM’s Survey

I. Introduction

II. Discussions on Transportation Considerations – Regulatory, Practice and Hazard Characteristics Definitions of gas and liquid; Reid Vapor Pressure (RVP); Degree of hazard; Packing Group; Flammability; Initial boiling point; DOT flammable liquid classif ication criteria; Emergency Response; Flammable gases dissolved in li quids; Hydrogen sulfide; Light crude oils; Bakken crude oil; Crude oil processing.

III. Survey Results

A. Testing Used to Evaluate Bakken Crude Oils

B. Test Methods Used to Characterize the Hazards o f Crude Oil

C. Reported Information and Test Results - Discuss ion and Range Flashpoint; Initial boiling point; Vapor pressure o f crude oil in transportation, tank car pressures; Flammable Gas Content; Hydrogen sulf ide content; Corrosivity to metals.

D. Response to additional PHMSA Survey Question

IV. Summary Remarks

Appendix 1 Questions Posed by PHMSA, January 29, 20 14

Appendix 2 PHMSA Field Office Questionnaire

Appendix 3 Paper submitted by Canada and the U.S. t o the 45th session of the UN

Subcommittee on the Transport of Dangerous Goods

Appendix 4 Test methods used to evaluate selected B akken Crude Oil Characteristics

Appendix 5 Guide page 128 from the 2012 Emergency Response Guidebook

Appendix 6 Glossary of Terms and Acronyms3

About the Author : This report has been prepared for AFPM by Frits Wybenga of Dangerous Goods Transport Consulting, Inc. Mr. Wybenga has more than forty y ears’ experience in the field of hazardous material s transportation. In 1971, he became the first U.S. Coast Guard officer with formal training related to hazardous materials in the Port of Houston, Texas. In succee ding years, he worked for the USCG in Washington, D C on matters dealing with technical and regulatory issue s on safety and environmental protection relating t o transportation of hazardous materials in bulk in tank barges, petr oleum tank ships, chemical tankers, and liquefied g as carriers. Based on extensive technical and international expe rience, in 1989, he assumed responsibility for lead ing international activities on the transport of hazard ous materials for the DOT Research and Special Prog rams Administration (subsequently renamed the Pipeline a nd Hazardous Materials Safety Administration). He served as the head of U.S. delegations to the United Nations Subcommittee of Experts on the Transport of Dangero us Goods (UNSCETDG) from 1989 to 2004 and served as the UN S ubcommittee vice Chairman for 8 years. In 2000, he became the Deputy Associate Administrator for Hazar dous Materials Safety and remained in this position until retiring from DOT in 2005. Among other recognition s, his contributions to safety and environmental pr otection were recognized by two separate DOT Secretary Silve r Metal Awards and two Hammer Awards signed by Vice President Gore. Since retiring from his DOT positio n, he continues to participate in the UNSCETDG, rep resenting a range of non-governmental organizations. He has de grees in chemical engineering, environmental engine ering and business administration. He qualified as a register ed professional engineer (chemical engineering) in the District of Columbia in 1974. He may be contacted at fwybenga@ dg-transportation.com.4



### Executive Summary

Recent incidents in the U.S. and Canada involving t he transport of Bakken crude oil originating in North Dakota has focused considerable attention on the transportation of Bakken crude oil by rail. Questions have been raised as to whether Bak ken crude oils pose substantially different risks than crude oils that have traditionally been transported. At the request of the Department of Transportation (DOT), the American Fuel & Petrochem ical Manufacturers (AFPM) conducted a survey of its members to address questions posed by DOT and developed this report of its findings. In addition to obtaining responses to th e questions DOT raised, as part of its survey, AFPM also collected data stemming from analysis of approximately 1400 samples of Bakken crude oil in order to better understand its propert ies.

This report assembles AFPM member responses to ques tions posed by DOT and provides summary data on Bakken crude oil characteristics an d hazards based on the sample information collected. The results show that Bakken crude oil may appropriately be classified as a flammable liquid based on DOT and international tra nsportation requirements. 1 Comparison of assay data on Bakken crude oil with data from non-B akken crude oils indicates that Bakken crude oil is within the norm with respect to the ha zard characteristics of a light crude oil. While Bakken crude (and other light crudes) may contain h igher amounts of dissolved flammable gases compared to some heavy crude oils, the percentage o f dissolved gases would not cause Bakken crude to be transported under a DOT hazard class ot her than Class 3 Flammable Liquid and does not support the need to create a new DOT classifica tion for rail transportation

. Flammable gas content correlates with vapor pressure. The maximu m vapor pressure observed based on data collected was 61% below the vapor pressure threshol d limit for liquids under the HMR; demonstrating that Bakken crude oil is properly cla ssified as a flammable liquid. With one exception, hydrogen sulfide concentrations were fou nd to be extremely low – below the Short Term Exposure Limits for workers established by OSH A regulations. In the exceptional case, concentrations were substantially higher. Where th ey exist, high hydrogen sulfide concentrations are addressed under existing transpo rtation and workplace safety regulatory provisions without affect to rail tank car authoriz ations. Data and experience indicate there to be no basis for classifying Bakken crude oil as hav ing a corrosivity risk as defined by DOT Hazardous Materials Regulations. 2

The information provided confirms that Bakken crude oil does not pose risks significa ntly different than other crude oils or other flammable liquids authorized for rail transport. Bakken and other crude oils have been classified as flamma ble liquids. As noted, Bakken crude poses a lower risk than other flammable liquids authorized for transport by rail in the same specification tank cars. Measured tank car pressures show that even the older DOT 111’s authorized to

1 The United Nations Recommendations on the Transpor t of Dangerous Goods form the basis for DOT regulat ions and regulations used widely throughout the world.
2 Title 49 of the Code of Federal Regulations Parts 105 to 180.5

transport Bakken crude oil are built with a wide ma rgin of safety relative to the pressures that rail tanks may experience when transporting Bakken crude oil.

Survey results are summarized below. Bakken crude oil currently is transported in compliance with the HMR as a Class 3 flammable Liquid in eithe r Packing Group I, II, or III. In conclusion, there is no identifiable basis for regulating Bakke n crude differently than other flammable liquids regulated by the DOT Hazardous Materials Regulation s.

Summary Table on Bakken Crude Oil Characteristics E valuated in AFPM’s Survey

Characteristic Reported Values Hazmat Transportat ion Regulatory Implications Flashpoint Range: -59 o C to 50 o C Bakken crude oils meet the criteria for Packing G roup I, II, or III flammable liquids or as combustible l iquids 3 Initial Boiling Point Range: 2.2 o C to 66.9 o C Bakken crude oils with an initial boiling point o f 35 o C or less meet criteria for Packing Group I flammable liquids; others for Packing Group II or III flammab le liquids or combustible liquids according to flashpo int Vapor Pressure at 50 o C Maximum: 16.72 psia All Bakken crude oils have a v apor pressure below 43 psia at 50 o C and must be transported as liquids Reid Vapor Pressure at 38 o C Maximum:15.4 psia Not used by the regulations; conf irm the vapor pressure at 50 o C is well below the above 43psia limit and Bakken crude oils must be transported as liquid s. Rail tank car pressures on delivery Maximum:11.3 psig Demonstrates that Bakken crude ma y be safely transported in DOT specification 111 tank cars 4 Flammable gas
content Maximum:12.0 liquid volume % None; with the vapor p ressures of all Bakken crudes oils examined not exceeding a vapor pressure of 43 psia at 50 o C, all Bakken crude oils examined must be transported as liquids Hydrogen sulfide content in the vapor
space Most reported H 2 S concentrations were below the OSHA STEL; one reported a maximum level of 23000 ppm None when low values are experienced; additional hazard communication to warn of the presence of H 2 S when inhalation hazard levels are encountered 5

Corrosivity NACE B+ or B++ Data and experience indi cate that Bakken crude oil does not corrode steel at a rate of 1⁄4 inch per year or more so that Bakken crude oil is not a corrosive li quid

3 Note the Bakken crude data submitted included only one sample that qualified as a combustible liquid, which has a lower risk than other flammable liquids.
4 §179.201-1 provides summary specifications for DOT -111 rail tank cars. Earlier DOT 111’s were design ed to a 240 psig burst pressure whereas later designs are d esigned to a minimum burst pressure of 500 psig. B ased on §179.15(b)(2)(ii) the minimum pressure relief valve settings for tank cars with a minimum burst pressu re of 240 psig is 35 psig and for 500 psig designs the minimum set ting is 75 psig.
5 See §172.327.6



### I. Introduction

The American Fuel & Petrochemical Manufacturers (AF PM) is an industry association representing virtually all of the petroleum refiner s and petrochemical manufacturers throughout the United States. The fuel and petrochemical manu facturing industries have a strong commitment to safety as well as environmental prote ction, and strive for opportunities to enhance safety and environmental protection. AFPM members depend upon a plentiful, affordable supply of crude oil as a feedstock for t he transportation fuels and petrochemicals that they manufacture. Approximately 11 percent of the crude oil processed by AFPM members is transported by rail.

As manufacturers, AFPM members acquire crude oils f rom multiple sources, including crude oil produced from the Bakken formation. Based on conce rns expressed by the U.S. Department of Transportation (DOT) over the properties of Bakken crude oil being transported by rail, AFPM, at DOT’s request, conducted a survey of its members in an effort to characterize various hazard characteristics that could be relevant to the trans portation of Bakken crude oils. For comparison purposes, the properties of crude oils from other f ields were also considered.

Bakken crude oil is derived primarily from northwes tern North Dakota and to a lesser extent northeastern Montana, and the bordering Canadian pr ovinces of Manitoba and Saskatchewan. Due to the lack of pipeline infrastructure, Bakken crude oil is transported extensively by rail. The data submitted in response to the survey demons trates that Bakken crude oil is properly transported in accordance with the DOT Hazardous Ma terials Regulations (HMR) as UN1267 Petroleum Crude Oil, or NA1993 Combustible Liquid, NOS.

Survey Scope

The initial questions posed to AFPM by DOT’s Pipeli ne and Hazardous Materials Safety Administration (PHMSA) on January 29 are attached i n Appendix 1 to this report. PHMSA personnel in a regional office posed additional que stions to AFPM members and these are attached in Appendix 2. These two sets of question s formed the basis for the survey conducted by AFPM. More recently, the experts from Canada an d the United States to the United Nations Subcommittee of Experts on the Transport of Dangero us Goods submitted a formal document noting recent rail transport incidents involving Ba kken crude oil and soliciting the input of the Subcommittee as to whether crude oil such as Bakken crude oil derived from fracking operations posed a different degree of risk than other crude o ils. 6 To the extent possible this report also responds to questions raised in the UN paper.

This report compiles information provided by 17 AFP M members who participated in the survey. Data analysis focused on Bakken crude oil as transported. Bakken data stems from sampling at loading points at well head locations, intermediate collection facilities (distribution

6 A copy of the UN Paper is reprinted in Appendix 3.7

centers) at which crude oil may be loaded into rail tank cars and at refinery locations taking receipt of crude oil after a rail journey. Data on approximately 1400 samples of Bakken crude oil was taken into account.



### II. Discussions on Transportation Considerations – Regulatory, Practice and Hazard Characteristics

While PHMSA’s Bakken Blitz data collection is ongoi ng, PHMSA staff has suggested that Bakken crude oil is different from other crudes oil s that have traditionally been transported by rail in the United States. The Canada/U.S. UN pape r reiterates this opinion concerning Bakken crude oil stating, “[t]his mostly ‘younger’ crude i s being found to contain significantly higher ‘light ends’ than what has been traditionally trans ported as UN 1267.” Again referring to crude oils like Bakken crude oil, the UN paper goes on to suggest, “lighter crude oil with a higher quantity of dissolved flammable gases pose a signif icantly different risk than heavier crude oils that do not have such a high constituency of more v olatile components.” Against this background, it may be instructive to first examine some relevant regulatory requirements, related crude oil hazard characteristics, and transport pra ctices, particularly as they relate to Bakken crude oil.

Definitions of gas and liquid. 7 The HMR base the definition of a gas on whether a s ubstance is a gas at 20 o C (68 o F). Substances with a vapor pressure of more than 300 kPa (43.5 psia) at 50 o C (122 o F) are also considered as gases irrespective of whe ther any liquid is still present at that temperature. Substances that have a vapor pressure of not more 300 kPa (43.5 psia) at 50 o C (122 o F) and with a melting point at or below 20 o C (68 o F) are generally considered liquids. Crude oil, including Bakken crude oil, is properly classified as a liquid – irrespective of light end concentration – provided its vapor pressure is not more than 300 kPa (43.5 psia) at 50 o C (122 o F). The AFPM survey confirms that vapor pressures of Ba kken crude oil are well below the 300 kPa
at 50 o C (122 o F) limit and are properly transported as liquids un der the HMR.

Reid Vapor Pressure (RVP). Reid vapor pressure is a common measure of a subs tance’s vapor pressure at 100 o F (38 o C). The RVP of crude oil increases with the increa sing presence of flammable gases and other volatile flammable liquid components (e.g., pentanes).

Up until 1990, prior to harmonization of the HMR wi th international regulations, the HMR used RVP in place of the 300 kPa at 50 o C (122 o F) criterion for differentiating between a liquid a nd a

gas. 8 A substance with an RVP of 40 psia or less was re garded as a liquid. In addition, earlier editions used flashpoint and RVP as a basis for ide ntifying authorized packagings, including authorized rail tank cars, for various flammable li quids. Then, §173.119 differentiated substances with an RVP of 16 psia or less from more hazardous substances with RVP’s between

7 See 49 CFR § 171.8.
8 49 CFR §173.119 (1990 ed.).8

16 and 27 psia and 27 and 40 psia; and used an RVP of 40 psia as the threshold for use of DOT specification 111 tank cars. It is noteworthy that Bakken crude oil RVP values obtained in this survey were all less than 16 psia so that the corre sponding crude oils would all have been subject to earlier HMR packaging requirements appropriate f or the two prior lowest hazard flammable liquid categories.

RVP continues to be used by other regulatory agenci es and the petroleum industry. For example, U.S Coast Guard (USCG) regulations for tank ships a nd tank barges still use a 40 psia RVP criterion for differentiating between liquids and g ases in the case of petroleum products, including crude oils. The USCG regulations permit substances to be transported in integral tanks (i.e., gravity tanks not designed for any appreciab le pressure) when regarded as liquids (i.e., RVP of 40 psia or less). 9

Though no longer used in the HMR, the considerable information on the RVP of Bakken crudes serves to provide insight into the characteristics of crude oils derived from the Bakken formation. The current regulatory limit of 300 kPa at 50 o C is only marginally different from RVP in the case of crude oils so that RVP values may be deemed a close approximation of the vapor pressure at 50 o C (122 o F).

Degree of hazard. The HMR vary the stringency of requirements accordi ng to the degree of risk various substances pose in transportation. Ma ny hazards, including the flammability hazard of liquids, are subdivided into three risk levels:

Packing Group I – encompasses substances regarded a s posing a high hazard level; Packing Group II – encompasses substances regarded as posing a medium hazard level; and Packing Group III – encompasses substances regarded as posing a low hazard level.

Packing Group as it pertains to rail transport. While Packing Group is commonly used in the HMR for purposes of tiering the severity of regulat ory requirements, in the case of rail transport of crude oil, it should be noted that DOT 111 rail tank cars are authorized for transporting Packing Group I, II and III crude oils under UN1267

. 10 DOT 111’s are widely used for transporting Bakken crude oil. While the HMR also authorize AAR Class 206 rail tank cars for Packing Groups II and III crude oil, these are lega cy tank cars with few remaining in service. As such, Packing Group, in practice, has little to no impact on the integrity of rail tank cars used in transporting Bakken crude oil since DOT specificati on 111 tank cars are in common usage. 11

DOT regulations and publications suggest that Packi ng Group is a secondary consideration in the case of emergency response. HMR placarding and rai l tank car markings requirements, which are intended to communicate essential emergency res ponse information, to emergency responders in the event of an accident or incident, do not communicate the Packing Group of the

9 See 46 CFR §§ 30.10-22 (definition of a flammable liqu id) and 30.10-39 (definition of a liquefied flammab le gas).
10 See 49 CFR §§ 173.242 and 173.243.
11 For combustible liquids AAR 203W (less than 100) a nd 211W (less than 1100) tanks are also authorized.9

hazmat involved. Further, the 2012 Emergency Respo nse Guidebook (ERG) 12 does not take Packing Group into account when advising emergency responders on immediate first response

measures.
The HMR require shippers to include the Packing Gro ups of hazardous materials on shipping papers and for rail transport this second level inf ormation for crude oil and other hazardous materials is available to emergency responders by a ccessing the train consist. 13 Bakken crude is described on shipping papers (or the train consist) depending on Packing Group in the following concise well recognized format:

- UN1267, Petroleum crude oil, 3, I;

- UN1267, Petroleum crude oil, 3, II; or

- UN1267, Petroleum crude oil, 3, III.

When Bakken crude oil is transported in DOT 111 rai l tank cars, as is common practice, the difference in shipping paper descriptions is the on ly regulatory difference distinguishing Packing Group I, II or III Bakken crude oils as they are tr ansported by rail.

Flammability. Flammable gases and vapors will ignite when they ar e mixed with air in certain concentration ranges. The lowest temperature at wh ich flammable liquids produce vapor in sufficient amounts to support combustion is termed the liquid’s flashpoint

. Under DOT and international regulations, a flammabl e liquid is a liquid that has a flashpoint of less than or equal to 60 o C (140 o F). Flammable liquids with a flashpoint of 23 o C (73 o F) or less are assigned to either Packing Group I or II. In e ssence, the flashpoint limits of 23 o C (73 o F) and
60 o C (140 o F) for flammable liquids indicate whether a substan ce has:

- Potential of producing a flammable vapor under mode rate ambient temperature conditions – i.e., 23 o C (73 o F); or

- Potential of producing a flammable vapor under the most extreme ambient temperature conditions – i.e., 60 o C (140 o F).

Under the HMR, a flammable liquid with a flashpoint in the range of 38 o C (100 o F) and 60 o C (140 o F) may also be regarded as a combustible liquid, re flecting that such substances have a lower risk of igniting. Combustible liquids also i nclude liquids with a flashpoint up to 93 o C (200 o F).

Except for classification under the HMR, flashpoint is not commonly used to characterize crude oil. Testing for flashpoint is an inherently dange rous test to conduct even under controlled laboratory conditions. Given the specific threshol d values in the HMR, measurement of an exact

12 The ERG is periodically prepared and published joi ntly by DOT and the governments of Canada and Mexic o. Registration fees collected from hazmat shippers an d carriers in accordance with 49 CFR Subpart G supp ort its wide distribution to emergency responders in the U.S.
13 See 49 CFR §§ 172.202(a) and 174.26.10

flashpoint value is not required. For compliance w ith the HMR, it is important to know what range of values the flashpoint of a particular crud e oil falls into (e.g.; 23 o C or less) – not the specific flashpoint value. For this purpose, appro ximation methods may be used (e.g.; chromatography or calculation methods). This may b e common practice in the case of routine screening of crude oil shipments. Test methods ide ntified by the HMR are typically not valid for substances below -30 o C (-22 o F); and approximation methods may have been used in producing some of the flashpoint data discussed in this repor t.

While there is no regulatory limit on how low the f lashpoint of a flammable liquid may be, diethyl ether, a Packing Group I flammable liquid t ransported as a pure substance, has a flashpoint of -45 o C (-49 o F).

Initial boiling point. The HMR and international regulations use initial b oiling point as a classification criteria. Boiling point is consider ed indicative of a substance’s volatility or its propensity to form flammable vapor plumes in air. Plume formation could occur after a spill of a flammable liquid when a fire is not involved. Incr easing volatility leads to the formation of larger flammable vapor plumes. A lower boiling poi nt generally implies increased volatility. As such, boiling point is used to evaluate the degree of risk a flammable liquid poses. The larger the flammable vapor plume a flammable liquid is capable of forming when spilled, the more dangerous it is considered to be, since the size of the plume affects the probability that flammable vapors will reach an ignition source and ignite. Predicting the size of a plume a particular liquid produces involves complex calcula tions accounting for ambient conditions and many other properties of a substance. Since boilin g point is widely available, it is used as an approximation for gauging a substance’s volatility. The HMR use initial boiling point as the basis for a differentiating between substances that have a Packing Group I high hazard risk (i.e., an initial boiling point of less than 35 o C (95 o F)) or a Packing Group II medium hazard risk.

Pure substances have a single boiling point and boi l off completely at one temperature. Mixtures of flammable liquids made up of various components, like crude oil, boil over a temperature range. The more volatile components (e.g., dissolv ed gases in the case of crude oils) will boil off at the initial boiling point leaving less volatile components with higher boiling points in the liquid. Increasingly higher temperatures are requi red to boil off remaining components. Subsequent less volatile and less dangerous (from a flammability perspective) fractions of a liquid mixture may not boil off until significantly higher temperatures are reached. An assay of a Bakken crude oil indicates a boiling point range sp anning approximately 500 o C. From a flammability/volatility perspective, in comparing a pure substance with a flammable liquid mixture with the same initial boiling point, the pu re substance is more volatile and more dangerous.11

DOT flammable liquid classification criteria. The HMR and international regulations classify flammable liquids into three Packing Groups as foll ows:

Packing Group Flash point (closed

- cup) Initial boiling point

I ≤35 °C (95 °F)
II <23 °C (73 °F) >35 °C (95 °F)
III ≥23 °C, ≤60 °C (≥73 °F, ≤140 °F) >35 °C (95 °F)

Emergency Response. An important function of the HMR is to provide haza rd information to emergency responders in the event of an accident or incident involving a hazardous material in transportation. The HMR hazard classification requ irements result in the assignment a hazard class (e.g., flammable liquid), assignment of a UN number and proper shipping name and assignment of Packing Group. These determinations in turn lead to requirements for labeling and placarding to pictorially communicate the vario us HMR hazards, package markings to convey the UN number and proper shipping name, and shipping paper requirements providing additional information on the details of a hazardou s material shipment.

The 2012 Emergency Response Guidebook (ERG) is inte nded to supplement hazard communication information provided on packages and shipping papers. It is intended for use by emergency responders first arriving on the scene of an accident or incident. First responders include law enforcement personnel and fire departme nt personnel – both professionals and volunteers. DOT distributes the ERG widely through out the United States with the objective of making it available to every potential first respon der. The frequency of hazardous materials accidents and incidents is rare so that on average a first responder is expected to encounter less than one incident in a career. As such information must be basic and understandable to those who have a low probability of encountering a hazard ous materials accident or incident.

The ERG serves this purpose. Through the UN number or proper shipping name of a substance, a first responder is able to access instructions on what steps to take upon arrival at the scene of an accident or incident. For crude oil assigned to UN 1267 Petroleum crude oil, irrespective of Packing Group, or crude oil meeting combustible liq uid criteria and transported under NA 1993 Combustible liquid, NOS, guide page 128 of the ERG provides a first responder with the appropriate information (see Appendix 5). In this respect, it is important to note that the range of crude oils subject to the HMR (i.e., crude oils of Packing Groups I, II and III and combustible liquid crude oils) are addressed by one set of inst ructions made available to first responders. The same guide page is applicable to many other flammab le liquids independent of the degree of hazard.12

Flammable gases dissolved in liquids. Gases typically dissolve to some degree in liquids. For a given temperature, the amount of gas that dissolv es in a liquid is directly proportional to the partial pressure of the gas in equilibrium with the liquid. The amount of gas that can dissolve in a liquid increases with pressure and decreasing tem perature. For this reason, soda in a bottle bubbles when the top is removed as carbon dioxide h eld in the liquid is released as a gas because the bottle pressure no longer holds the carbon diox ide in the liquid. The same happens with crude oil where flammable gases such as methane, et hane, propane and butane, held in solution under high pressure underground, are released as th e pressure is decreased when it is brought to the surface and stored. If stored at a low temperature, crude oil will reta in more gas than if stored at a higher temperature.

Crude oil taken from the wellhead and placed in a s tabilization tank continues to release dissolved gases until an equilibrium concentration between the gas dissolved in the crude oil and the concentration of the gas in the tank vapor spac e is reached.

The DOT definition of a gas places a regulatory lim it on the amount of flammable gas that may be held in crude oil in transportation. If a crude oil had a vapor pressure in excess of 300 kPa at
50 o C (122 o F) due to a high dissolved gas concentration, it wo uld be regarded as a gas and not as a liquid.

In some cases the HMR explicitly permit some quanti ties of certain gases to be transported in liquids. For example, up to 30% ethylene oxide (a toxic and flammable gas) may be transported in propylene oxide (a liquid) under UN 2983 Ethylen e oxide and propylene oxide mixtures.

Hydrogen sulfide. In a pure form hydrogen sulfide is a gas and is reg ulated as a toxic and flammable gas under the HMR and OSHA regulations. Crude oil commonly contains some amount of sulfur. It may be present in hydrocarbon molecules (e.g., mercaptans) or as hydrogen sulfide dissolved in the liquid. The chemical/ther mal and biological breakdown of the sulfur bearing hydrocarbon molecules in crude oil, as it i s brought to the surface and is stored, may lead to increased evolution of hydrogen sulfide gas in c rude oil liquid and vapor.

When a crude oil contains concentrations of hydroge n sulfide at levels that may present an inhalation hazard, the HMR require communication of its presence. Bakken crude oil is generally considered a sweet crude and the survey d ata confirm that sulfur and hydrogen sulfide concentrations are normally low. However, exceptio ns were noted in the case of one respondent.

Light crude oils. Light crude oils are generally regarded as those crude oils with an API gravity of 37 degrees or more. API gravity varies inversely with specific gravity so that increasing API gravity values reflect decreasing specific gravity or density. Light crudes tend to have higher concentrations of light ends (i.e., methane, ethane , propane, butanes and pentanes). The presence of increasing amounts of dissolved gases and other light ends (i.e., pentanes) has the effect of increasing the crude oil’s vapor pressure, lowering its flashpoint and lowering its initial boiling point. Light crude oils may qualify as Packing Gro up I, II or III flammable liquids under the13

HMR depending on properties of the specific crude o il. Some may be transported as combustible liquids. Light crude oils are common t hroughout the world. Bakken crude oil is regarded as a light crude oil.

Bakken crude oil. Bakken crude oil, like other crude oils, consists o f a range of primarily hydrocarbon gases and liquids. The table below ill ustrates the composition of a Bakken crude oil sampled at a distribution center prior to loading f or rail transportation. The table also provides the HMR classification for each component. Divisio n 2.1 refers to the HMR flammable gas classification and Class 3 refers to the HMR flamma ble liquid classification. The particular Bakken crude oil sample depicted in the sample belo w had an RVP of 7.6 psia. 14

Hydrocarbon
gas Concentration in

Liquid Volume % DOT Classification

Methane <0.01 Div. 2.1 Gas Ethane 0.05 Div. 2.1 Gas Propane 0.80 Div. 2.1 Gas Iso-Butane 0.46 Div. 2.1 Gas N- Butane 2.36 Div. 2.1 Gas Total Gas 3.67 Neopentane <0.01 Class3; PG I Iso-Pentane 1.33 Class 3; PG I N-Pentane 2.36 Class 3; PG II Hexanes 4.10 Class 3; PG II Heptanes Plus 88.56 Varies Class 3; PG II tocombustible liquid to nonregulated Benzenes 0.08 Class 3; PG II

For the same crude oil, the figure below provides t he boiling point range. Note that the boiling point temperature progressively increases after the more volatile components are boiled off.

14 Among assays of Bakken crude oil, 7.6 psia is a no rmal RVP value.14 15

Consideration of flashpoint and boiling point data for hydrocarbons suggests that, for the crude oil illustrated, when 40% of the crude oil is boile d off, the remainder would not be regulated as a flammable liquid. 16 As boiling continues beyond the 40% level, the re maining liquid would transition from a combustible liquid to a non-regul ated substance. All else being equal, a pure flammable liquid with a boiling point comparable to the initial boiling point of the example crude oil would produce a flammable vapor plume 2.5 times larger than the example crude. 17 While a rough comparison, it illustrates that pure substances may be considerably more volatile than flammable liquid mixtures with identical initi al boiling points.

The range of boiling points also suggests that in a ccident conditions where a tank is engulfed in flames, considerably more heat would be required to boil off the example crude oil than would be required of a pure substance with the same IBP. Consequently, based this and other factors, pressure buildup within a tank containing the examp le crude oil would be expected to be more gradual than that for a pure substance.

15 IBP values in this chart where based on ASTM 5307, a capillary chromatography method, producing lower values as compared to IBP data from samples provided which were based largely on ASTM D 86 – a method referen ced in the HMR.
16 Estimated based on the properties of n-dodecane, a C-12 hydrocarbon with a flashpoint of 71 o C and a boiling point of 216 o C, which is not subject to the DOT HMR as a flammab le liquid. Crude oil compositions with a boiling point of 216 o C or higher were assumed to not qualify as flammabl e liquids with a flashpoint less than 60 o C.
17 Some examples of other Class 3 Flammable Liquids t hat are transported in DOT 111’s with a higher risk profile than Bakken crude would include: dieth yl ether, acrylonitrile, and ethyl mercaptan.

0 10 20 30 40 50 60 70 80 90 100

-50 0 50 100 150 200 250 300 350 400 450 500 550% Boiled Off

Boiling Temperature in ◦C



## Boiling Point Range for Typical Bakken Crude15

Crude oil processing. When crude oil is extracted, it is typically proces sed to remove water and entrained gases, and stored in a tank prior to tran sportation. Processing, settling time in storage tanks and ambient temperature conditions all influe nce the extent to which light ends including gases are released from crude oil before it is tran sported.



### III. Survey Results

A. Testing Used to Evaluate Bakken Crude Oils

As a Class 3 flammable liquid or a combustible liqu id under the HMR, Bakken crude oil is subject to evaluation of its flashpoint and initial boiling point for classification purposes in accordance with the HMR. Other tests evaluating va por pressure, flammable gas content, hydrogen sulfide content and corrosivity are also e mployed by industry and provide additional information relative to the hazards of crude oil.

Tests are carried out on crude oil samples taken at multiple locations along the distribution chain as it moves from the production point at a well to a refinery destination. Samples may be taken and evaluated at the well head, at gathering statio ns, at rail loading facilities, at pipeline facilit ies and when it is received at the refinery. Survey re sponses include data resulting from testing by AFPM members or independent laboratories (e.g. assa ys). 18 Data considered relevant for purposes of this survey was limited to data charact erizing crude oil “in transportation,” – ranging from data on samples taken at the well head locatio n at the point of loading for transportation to data from samples taken where transportation ended at the refinery gate.

Members generally found variations in properties of specific crude oils to be minimal as these crude oils moved through the distribution chain. S ummary data provided in the survey aggregates data obtained for samples taken along th e distribution chain. A number of members noted seasonal variations in some properties of Bak ken crude oils. The variations may be attributable to higher retention of flammable gases in crude oils in winter owing to lower ambient temperatures.

B. Test Methods Used to Characterize the Hazards of Crude Oil

PHMSA requested information on test methods used to characterize crude oil. The test methods used to evaluate selected characteristics are provi ded in Appendix 4.

18 Crude oil assays are detailed evaluations of crude oils that are commonly performed for commercial no nregulatory purposes. They may be used to define cr ude oil purchased by a refiner from a producer. Th e values reported in an assay reflect the properties of a sp ecific sample. They are intended to represent char acteristics of crude oils to be purchased and do not normally acco unt for variations that may be identified among mul tiple samples. For example, higher RVP values for Bakke n crude oil are noted in this survey for other samp les. In addition, data from more than one assay was used in this report. Even though the data in assays are n ot normally used for regulatory compliance purposes, considerat ion of assay data was instructive for purposes of t his survey given the detailed information they provide.16

C. Reported Information and Test Results - Discussi on and Range

The following information on Bakken crude oil is ba sed on responses from AFPM members and data provided on approximately 1400 samples of Bakk en crude oils. 19 The data included data points on specific characteristics as follows:

Flash Point: 77 data points; Initial Boiling Point: 275 data points; RVP: 807 data points; Rail Tank Car Pressure (PSIG): 387 data points; Total C1-C4: 18 data points;
H 2 S in Liquid: 37 data points;
H 2 S in Vapor: 535 data points; and Corrosivity to metal: 7 data points. 20

For comparison purposes data from samples of non-Ba kken crude oil was also considered.

1. Flashpoint

Reported Bakken flashpoint range. Survey respondents reported flashpoints ranging fro m -59 o C (-74 o F) to 110 o C (230 o F). On the basis of this flashpoint information, Bakken crude oil in transportation ranges from being subject to regula tion as flammable liquids (in all 3 Packing Groups), combustible liquids or not regulated as ha zardous materials under the HMR.

The chart below shows the distribution of flashpoin ts among all Bakken crudes for which data was provided as part of this survey.

19 Many of the samples were collected in February/Marc h 2014 in North Dakota. Given the prevailing ambient temperature, these samples are expected to represent “worst case” conditions that contribute to higher flashpoint, vapor pressure and dissolved gasses. 20 Data provided was initially acquired for a range o f purposes and not necessarily for compliance with the HMR. As such data on samples did not always include data points on all of the characteristics considered in the survey.Discussion on flashpoint data. Survey data indicate that

classification criteria for Packing Group provided could be classified either

As already noted, flashpoint data may be based on e stimation methods with the objective of determining the HMR flashpoint these methods suffice for HMR classificati appropriate flashpoint range they may not accurately reflect the would be obtained using a method identified as suit able under the HMR. advised when consid ering specific values.

0 5 10 15 20 25

-60 to -50 -50 to -40 - 40 to -30Count 

## Flash Point Frequency for Bakken Crudes

Survey data indicate that

76 of the 77 crude oil sample Packing Group I or II. One crude oil sample for which data was either as Packing Group III or as a combustible liquid.

As already noted, flashpoint data may be based on e stimation methods with the objective of determining the HMR flashpoint range a particular crude oil falls into (e.g., 23 o C or less). While classificati on purposes in that they assign a substance to the they may not accurately reflect the precise flashpoint value would be obtained using a method identified as suit able under the HMR. As such caution is

ering specific values.

40 to -30 to -20 -20 to -10 -10 to 0 0 to 10 10 to 20 20 to 30 30 to 40 Flash Point Result (Deg C) 

## Flash Point Frequency for Bakken Crudes

Mean -27.1 o C (-16.8 o F) Median -36 o C (-32.8 o F) Mode -15.0 o C (5 o F) Minimum -59 o C (-74.2 o F) Maximum 50 o C (122 o F)

17 sample s meet the for which data was a combustible liquid.

As already noted, flashpoint data may be based on e stimation methods with the objective of C or less). While in that they assign a substance to the

flashpoint value that As such caution is 30 to 40 to 502. Initial boiling point

Reported Initial Boiling Points. that was provided on Bakken samples from crude oil in transportation.

Discussion o n Initial Boiling Point information majority of Bakken crude oils in transportation
50 o C. The low values shown in the lower upon arrival at a refinery in the months of Februar y to April su seasonal conditions.

The HMR utilize an IBP threshold criterion of 35 Among Bakken crude oils, IBP values Respondents to the survey noted While no misclassification is implied, value combined with repeatability challenges with respect to the assignment to

3. Vapor pressure of crude oil in transportation, tank car pressures

Reported vapor pressure at 50 o C samples. The vapor pressure values ranged from a l ow of 13.89 psia to 16.72 RVP data these values appear to be in the high rang e of what would normally be expected Bakken crude oil – although well below the vapor pressure threshold fo r a flammable gas The chart below describes the range of initial boil ing point data that was provided on Bakken samples from crude oil in transportation.

Mean 29.0 o C (69.6 o F) Median 30.7 o C (87.3 o F) Mode 30.2 o C (86.4 o F) Minimum 2.2 o C (36.0 o F) Maximum 66.9 o C (152.4 o F)

n Initial Boiling Point information

. Based on the data provided in the survey, t

in transportation have an initial boiling point rang ing from low values shown in the lower left hand side of the chart stem from samples taken upon arrival at a refinery in the months of Februar y to April su ggesting that IBP is influence

threshold criterion of 35 o C to delineate between Packing Group values are clustered around the regulatory threshold. noted problems with the variability and repeatability of While no misclassification is implied, the clustering of IBP values around the 35

repeatability problems associated with IBP testing could present assignment to Packing Group I or II.

of crude oil in transportation, tank car pressures

C

. Vapor pressure values were reported in data on nine Bakken samples. The vapor pressure values ranged from a l ow of 13.89 psia to 16.72 psi RVP data these values appear to be in the high rang e of what would normally be expected

although well below the vapor pressure threshold fo r a flammable gas

18

The chart below describes the range of initial boil ing point data

Based on the data provided in the survey, t he ing from 15 o C to hand side of the chart stem from samples taken

ggesting that IBP is influence d by

Packing Group I and II. threshold. repeatability of IBP tests. of IBP values around the 35 o C threshold present practical

Vapor pressure values were reported in data on nine Bakken psi a. Based on RVP data these values appear to be in the high rang e of what would normally be expected for although well below the vapor pressure threshold fo r a flammable gas . Allbut two samples were taken at the

samples taken in February and March at other times during the year when ambient tempera tures are higher. Bakken crude oils fall within the d the 300 kPa (43 psia) threshold value delineating between a gas and a liq uid

Note that the vapor pressure at 50 reported RVP which is measured at 38

Reported Reid Vapor Pressure values respondents and based on the data found to have RVP values ranging

The chart below shows the distribution of RVPs amon g all Bakken crudes for which data was obtained as part of this survey.

21 The seasonal variation of RVP is discussed below.

were taken at the rail loading point in North Dakota. These values were f in February and March 2014. Lower vapor pressure values would be anticipated at other times during the year when ambient tempera tures are higher. 21 The data Bakken crude oils fall within the d efinition of a liquid under the HMR in that they are well below

threshold value delineating between a gas and a liq uid

. Note that the vapor pressure at 50 o C will normally correlate closely with the far more widely

is measured at 38 o C (100 o F) as discussed below.

Reported Reid Vapor Pressure values (vapor pressure at 38 o C (100 o F)). Among the data submitted, Bakken crude oil offered for transportation ranging from 0.8 to 15.54 psia.

The chart below shows the distribution of RVPs amon g all Bakken crudes for which data was

The seasonal variation of RVP is discussed below.

19 These values were f

rom values would be anticipated The data confirm that in that they are well below

C will normally correlate closely with the far more widely

Among the survey Bakken crude oil offered for transportation was

The chart below shows the distribution of RVPs amon g all Bakken crudes for which data wasSeasonal variations of RVP. Seasonal variations of RVP are demonstrated in the following

chart.

The chart shows that RVP values psia during colder periods. RVP and other parameters are interrelated. As such , s variations in other parameters such as flashpoint, init are likely.

Operational limits on crude oil RVP operational limits on the RVP of crude oil. roof tanks. Environmental regulations governing the release of volatile organic compounds (VOCs) restrict the RVP (or a variant known as TVP measured at ambient temperature) of crude oil in floating roof tanks to 10- 11 psia. The floating roof tank pressure l RVP limits on the crude oil transported b monitor crude oil for RVP to ensure compliance with respondent noted that they test the RVP of receipt. In their experience RVP values varied ac cording to the time of year with RVP values as high as 15 psia in the winter and with lower RVP va lues typical in the summer. operational re striction on the transportation of potential for pump cavitation. A limiting RVP of 1 0 psia was reported as typical for crud transported by pipeline where pumping is required crude oils transported by rail. Finally, l operational perspective. One refinery respondent n oted a contractual RVP limit of 9.5 psia. Seasonal variations of RVP are demonstrated in the following

The chart shows that RVP values average 8 psia for warmer times of the year and average 12. 5 RVP and other parameters are interrelated. As such , s such as flashpoint, init ial boiling point, and flammable gas content

Operational limits on crude oil RVP . Respondents noted that, outside of the HMR operational limits on the RVP of crude oil. First of all, i t is common to store crude oil in floating

Environmental regulations governing the release of volatile organic compounds (VOCs) restrict the RVP (or a variant known as TVP measured at ambient temperature) of crude 11 psia. The floating roof tank pressure l imits impose practical transported b y rail to refiners and petrochemical facilities. monitor crude oil for RVP to ensure compliance with these environmental regulations. respondent noted that they test the RVP of every rail shipment at the time of loading and upon receipt. In their experience RVP values varied ac cording to the time of year with RVP values as high as 15 psia in the winter and with lower RVP va lues typical in the summer.

striction on the transportation of high RVP value crude oils is due to increased potential for pump cavitation. A limiting RVP of 1 0 psia was reported as typical for crud

where pumping is required . Pipelines are a destinatio n for some Bakken Finally, l ower RVPs are also more desirable from a refinery operational perspective. One refinery respondent n oted a contractual RVP limit of 9.5 psia.

20 Seasonal variations of RVP are demonstrated in the following

8 psia for warmer times of the year and average 12. 5 RVP and other parameters are interrelated. As such , s imilar seasonal ial boiling point, and flammable gas content

the HMR , there are t is common to store crude oil in floating Environmental regulations governing the release of volatile organic compounds (VOCs) restrict the RVP (or a variant known as TVP measured at ambient temperature) of crude imits impose practical rail to refiners and petrochemical facilities. Recipients

environmental regulations. One every rail shipment at the time of loading and upon receipt. In their experience RVP values varied ac cording to the time of year with RVP values as high as 15 psia in the winter and with lower RVP va lues typical in the summer. The second high RVP value crude oils is due to increased potential for pump cavitation. A limiting RVP of 1 0 psia was reported as typical for crud e oils n for some Bakken ower RVPs are also more desirable from a refinery operational perspective. One refinery respondent n oted a contractual RVP limit of 9.5 psia.21

Reported rail tank car pressure measurements. The chart below indicates pressures measured in rail tank cars upon arrival at a refinery. The hig hest value reported was 11.3 psig. This value is lower than the 35 psig minimum relief valve setting for older DOT 111 rail tanks cars and their required 240 psig minimum design burst pressure. T his suggests that DOT 111’s are built with an ample margin of safety relative to the pressures that rail tanks may experience when transporting Bakken crude oil.

Mean 8.5 psig Median 8.5 psig Mode 9.0 psig Minimum 4.2 psig Maximum 11.3 psig

4. Flammable Gas Content

Reported flammable gas concentrations. In response to the PHMSA question on ranges of flammable gas content of Bakken crude oil, responde nts reported the following ranges: 22

Hydrocarbon gas Concentration in Liquid Volume %

22 In data collected, some samples were found to hav e higher values than indicated in the range of values reported. Maximum values were 0.77 LV % for ethane, 3.4 LV % for propane, and 8.0 LV % for butane. As reflected in the bar chart below, b ased on sample data, the maximum total flammable gas content for all samples was 11.9 LV %. Samples were obtained in February and March.

0 0 0 0 4 6 40 95 91 103

44

4 0
0 20 40 60 80 100 120Count

PSIG Range 

## Rail Tank Car Pressure Frequencies (psig)22 Methane <0.01 Ethane 0.50 Propane <1-2% Iso-, N-Butane 3-4%

Eighteen samples included measurements of flammable gas content. The information differs from light end content in that pentane, which is no t a gas under the HMR, is commonly included in light end data. Data from three respondents ind icated a maximum total flammable gas content (C1 to C4) of 3.5% Liquid Volume %.

Information provided by a fourth respondent, includ ed data from 12 samples taken in a one month period beginning in early February and ending in early March. In the case of the latter samples, total flammable gas content ranged from 5. 9% to 11.9%. Ambient temperatures affect these gas concentration values. The data obtained from all respondents is illustrated in the chart below.

2 4

0 3

1 1 2

0 2 3

0 1 2 3 4 5

2

- 3 3

- 4 4

- 5 5

- 6 6

- 7 7

- 8 8

- 9 9

- 10 10

- 11 11

- 12Count

LV% Range



## C1 Through C4 Frequency23

Comparison with other crude oils. To determine whether Bakken crude oil’s “light end” content is markedly different from other crude oils, data ( primarily from assays) for other non-Bakken crude oils were examined. 23 The table below illustrates that some selected ot her crude oils have comparable gas contents and in addition illustrates some of the variations in characteristics that exist among crude oils with a range of API gravitie s. (Note that “light ends” as the term is used in the petroleum industry includes pentanes which a re deemed flammable liquids under the HMR.) Based on assay data for Bakken and non-Bakke n crude oils 24 , the following table summarizes data obtained:

Crude Name Origin API RVP (psia) Vol % of Light Ends (C2 – C5) Arabian Super Light Saudi Arabia 51 20.7 12.53 wt % 25 (C1-C4 only) Eagle Ford Texas 48 7.95 8.3 Agbami Nigeria 48 2.2 5.61 wt % DJ Basin Colorado 45 7.82 8.0 Sarahan Blend Algeria 43 7.46 8.1 Bakken North Dakota 42 7.83 7.2 WTI Texas / New

Mexico 41 5.90 6.1

Brent 26 United Kingdom 37.5 9.33 5.28 wt % API gravity of 37 or more defines light crude oil 37

LLS Louisiana 36 4.18 3.0 Alvheim blend Norway 34.9 3.9 1.86 wt % Arabian Heavy Saudi Arabia 28.4 18.3 5.13 wt % (C1-C4) Alberta Dilbit 27 Alberta 21.1 7.18 7.30 wt % Alba United Kingdom 19.6 1.6 0.14 wt %

23 Note “light ends” as the term is used in the petroleum i ndustry includes pentanes which are deemed flammabl e liquids under the HMR.
24 Sources included data collected as part of the surv ey as well as online data at http://www.oiltransport.info/crudedata/crudeoildata/crudeoildata. html and data at http://www.statoil.com/en/ouroperations/tradingprod ucts/crudeoil/crudeoilassays/pages/default.aspx

25 Because the specific gravities of gases and pentan es in the liquid state are lower than that of other components, “wt %” is lower than “LV %”. Conversion from wt % to LV% req uires the concentrations of each individual compone nt. 26 Data from a sample taken at the loading point.
27 Data from a sample taken at the loading point.24

Using assay data allows for evaluating oils on a co nsistent basis. While survey data on specific samples of Bakken crude oils (like other light crud e oils) showed higher gas content than assay data, it may be expected that similar variations ar ise in the case of non-Bakken crude oils. The data suggests that Bakken crude oil is within the n orm for what might be expected in the case of light end content in light crude oils. Light crude s oils are not unique to new drilling practices and have been common since the advent of petroleum extraction.

Operational limits on flammable gas content. Since flammable gas content and vapor pressure are closely linked, operational limitations identif ied relative to RVP (i.e., floating roof tank limits, pipeline pumping limits and refinery operat ional considerations) also apply in the case of flammable gas concentrations.

5. Hydrogen sulfide content

Reported hydrogen sulfide concentrations. Respondents indicated hydrogen sulfide vapor space concentrations were less than 10 ppm.

Data reviewed was for either hydrogen sulfide conce ntration in the liquid or hydrogen sulfide concentration in the vapor.

Data on H

2 S in liquid. For samples, hydrogen sulfide concentrations (in p pm) in the liquid were reported as follows:

H2S in liquid Count
x< 0.2 4
x<1.0 2
x< 2 22
x<5.0 1
x< 10 8
Total 37

These would suggest very low hydrogen sulfide vapor concentrations.

Data on H

2 S in vapors. Reports of hydrogen sulfide (in ppm) in the vapor were reported as follows:

H2S in Vapor Count
x<1 390
x<2.0 9
x>2000 6
Total 53525

The above six values indicating “x>2000” stemmed fr om one of four respondents providing H 2 S vapor data. In addition, the same respondent repor ted 129 measured H 2 S values (in ppm) that are summarized as follows:

H2S in Vapor
Mean 3580
Median 2000
Min 1
Max 23000

The data was based on samples taken at a gathering location where crude oil was being collected for transportation. For crude oils with H 2 S concentrations posing an inhalation hazard, additional HMR hazard communication requirements ap ply, including warnings on rail tanks

cars. 28

Operational limits on hydrogen sulfide. With an OSHA short term exposure limit (STEL) of 15 ppm for 15 minutes exposure, occupational limits ar e far below those warranting communication of the toxic hazard under the HMR. Where there is p otential for exposure, employees are fitted with monitors and ambient air is subject to gas sam pling. Testing for hydrogen sulfide is common for rail unloading operations and one respon dent noted that hydrogen sulfide levels greater than 15 ppm were not allowed at company rai l unloading facilities. Another respondent noted that where high hydrogen sulfide crude oils a re encountered, the crude oil is typically not transported before first being subjected to treatme nt using amine scavengers.

When appropriate, based on potential high levels of hydrogen sulfide which pose a health risk to workers, the risks of hydrogen sulfide are delineat ed on Safety Data Sheets.

6. Corrosivity to metals

Discussion. Under the HMR, in addition to criteria for corros ivity to skin, a substance is regarded as corrosive if it corrodes steel or alumi num at a rate of 6.25 mm (0.25 inches) per year. A substance with this degree of corrosivity would p enetrate steel used in crude oil rail tank cars in a period of approximately two years. There is n o evidence that Bakken crude corrodes steel or aluminum at this rate.

Reported corrosivity data. Data reported using NACE TM 172 indicates that Bakk en crude oil scores as either B+ or B++ using this method. Generally, a NACE value of B+ or better is

28 See 49 CFR §172.327.26

required for transportation via pipeline. While crude oil does not meet the HMR co rrosivity criteria, water, solids and H2S contaminants in cru de may cause corrosion at rates less than that specified in the HMR for classification purposes. Industry deals with this lower level of corrosion from an asset management perspective.

D. What safety information is provided to carriers ?

The HMR require that a considerable amount of infor mation be provided to carriers, including:

1. UN number of the crude oil; 2. Proper shipping name under which it is transport ed; 3. Hazard class (Class 3); 4. Packing Group of the crude oil; 5. Total quantity being offered or the number of pa ckagings (i.e., rail tank cars) involved; 6. Emergency response information that includes imm ediate hazards to health; risks of fire or explosion; intermediate methods to be taken for han dling fires; initial methods for handling spills or leaks in the absence of a fire; and preliminary first aid measures; and 7. A 24-hour emergency telephone number where more detailed information may be obtained.

Upon request, carriers may also be provided materia l safety data sheets.



### IV. Summary Remarks

Survey results obtained by AFPM members provide a c onsiderable amount of information on which to assess the hazard characteristics of Bakke n crude oil. The data obtained appears to be of good quality. From the data, it is clear that p arameters such as vapor pressures, initial boiling points, flashpoints and dissolved gas content were influenced by seasonal variations. Yet even when considering data obtained during periods of co ld weather, Bakken crude oil was found to be well within the limits for what is acceptable fo r transportation as a flammable liquid. Bakken crude oil was compared with other light crude oils and determined to be within the norm in the case of light hydrocarbon content, including dissol ved flammable gases.

Measured tank car pressures show that even the older DOT 111’s authorized to transport B akken crude oil are built with a wide margin of safety re lative to the pressures that rail tanks may experience when transporting Bakken crude oil.

Other factors influence the properties of crude tha t is transported. As manufacturers, AFPM members have an interest in limiting the RVP for pu rposes of operational efficiency and adherence to Clean Air Act requirements. RVP value s correlate with values for flammable gas content, initial boiling point and flashpoint. Lev els of all these parameters, consistent with an RVP of approximately 10 psia or lower are in the be st interests of AFPM members. Compliance27

with OSHA requirements related to exposure to H 2 S also plays a role in reducing the hydrogen sulfide content of crude oil in transportation.

AFPM and its members appreciate the concerns raised in relation to rail transport of Bakken crude oil and stand ready to work cooperatively wit h DOT and other governmental organizations to ensure the safe transportation of Bakken crude o il. This survey shows that Bakken crude oil does not pose risks that are significantly differen t than other crude oils and other flammable liquids authorized for transportation as flammable liquids. In some respects Bakken crude oil may be regarded as posing a lower degree of risk th an other flammable liquids transported in accordance with the HMR, particularly pure substanc es. 29

29 Some examples of other Class 3 Flammable Liquids th at are transported in DOT 111’s with a higher risk profile than Bakken crude would include: dieth yl ether, acrylonitrile, and ethyl mercaptan.28

Appendix 12930

Appendix 2

PHMSA Field Office Questionnaire

Company: Contact Name:

__________________ Address: Title:
City, State: Phone:
Type: Refinery  Transfer Terminal  Email:

• What tests, if any, are performed on the crude oil upon receipt?

o How frequently are they completed?

o Are you willing to share the results with us?

• When you find high levels of gases in crude, what a ctions do you require of your personnel before unloading?

o What information about the crude oil properties, if any, is provided by the offerors or carriers prior to receipt?

o How is this information communicated?

• Have you had to add any special safety measures or make any procedural changes in the unloading process to protect workers or modify the flow to the facility?

• Are there any prescribed limits involving vapor pre ssure, flammable gas concentration or hydrogen sulfide content above which the crude oil is not accepted at terminal or refinery?

o If so, what are these limits and how are they deter mined? ( Note: We have heard that one of the larger refineries in Canada placed gauges on top of rail cars to measure pressure before unloading and in turn rejec ted some 400 rail cars. )31

Committee of Experts on the Transport of Dangerous Goods and on the Globally Harmonized System of Classifica tion and Labeling of Chemicals

Sub-Committee of Experts on the Transport of Danger ous Goods

Forty-fifth session

Geneva, 23 June – 2 July 2014

Item 4 (c) of the provisional agenda Listing, classification and packing: miscellaneous



### Classification and hazard communication provision s for

crude oil

Transmitted by the experts from Canada and the Un ited States of

America 30



### Background

1. North America is experiencing a significant incr ease in crude oil supply, bolstered both by growing production in the Canadian oil sand s and the recent expansion of shale oil and natural gas production in the United States of America and Canada.
2. North American shale oil and natural gas extract ion has been mostly in geographic areas not linked to traditional crude oil or natura l gas pipelines, resulting in an increase in surface transport. Surface transport has also e nabled crude transport to different refinery capacities situated across North America. This mostly “younger” crude is being found to contain significantly higher “light ends” than what has been traditionally transported as UN 1267.

30 In accordance with the programme of work of the Sub-Committee for 2013-2014 approved by the Committee at its sixth session (refer to ST/SG/AC.1 0/C.3/84, para. 86 and ST/SG/AC.10/40, para. 14). Appendix 3


### United Nations 

# ST /SG/AC.10/C.3/2014/49


# Secretariat Distr.: General

2 April 2014

Original: English32 3. This significant and exponential increased in su rface movement of crude oil has led authorities within Canada and the United States of America to carefully consider transport safety impacts as well as potential impac ts to the environment. These efforts have been prioritized based on a series of major ac cidents across North America involving crude oil transport by rail - including a catastrophic incident brought to the attention of the Sub-Committee at its previous sess ion that caused numerous fatalities and destroyed much of Lac Mégantic, Quebec, in July 2013.
4. The increased production and experience has led to a renewed focus within North America on assessing the adequacy of the current pr ovisions governing crude oil transport. While an assessment of relevant rail ope rational conditions have been major components of this effort, a significant portion of the experience gained is relevant to all modes and would benefit from broader review and dis cussion within the SubCommittee. The purpose of this paper is to initiat e discussions relevant to the experience recently gained, to raise important ques tions regarding the proper classification of - and transport provisions for – crude oil, and to invite the SubCommittee to consider whether a review of the exist ing UN entries, assigned classifications, and transport provisions is warran ted. This discussion may also eventually encumber other petroleum products such a s natural gas condensates.
5. In particular, the Sub-Committee is invited to c onsider whether the current entries for crude oil in the Dangerous Goods List adequatel y distinguish between what can be significant variations in the flammable gas content of crude oils from different sources (see discussion below relevant to classification).



### Discussion

6. This document contains no proposals. The Sub-Com mittee is invited to provide feedback as a first step towards evaluating the eff icacy of the current provisions of the Model Regulations based on an evolving understandin g of the risks inherent in the transport of crude oil. Specifically, based on the information available on various types of crude oils in global transport today, the Sub-Co mmittee is requested to provide feedback with respect to the classification and haz ard communication elements of the Model Regulations currently applicable to crude oil

. (a) Classification
Unlike other Class 3 manufactured goods, organic ma terials from oil and gas production represent a unique challenge in rega rds to classification. Differences in the chemical makeup of the raw mater ial can vary day-today and from well head-to-well head. Unprocessed cr ude oil may present unique hazards based on the specific dissolved gas content, posing different hazards in transport. Would further disti nctions beyond merely identifying the Packing Group relevant to the flamm able liquid hazard or the flammable gas content of the crude be appropria te to account for the differing hazards posed by what can be significant quantities of dissolved flammable gases? What is the most appropriate meas ure of this volatility – boiling point or vapour pressure? Is the proposed measurement method a calculation based on the properties of the materi al or an observed value? What are the most appropriate sampling and testing procedures? And finally, at what threshold should revisions to the regulatory requirements be considered? (b) Hazard communication
The current flammable liquid entries in the Dangero us Goods List provide for a distinction in hazard by the assignment of Pa cking Groups based on33 the liquid’s boiling and flash points. However, lig hter crude oil with a higher quantity of dissolved flammable gases pose a significantly different risk than heavier crude oils that do not have such a high constituency of more volatile components. Would enh anced hazard communication distinguishing more volatile crude oi ls be beneficial for transport workers and emergency response personnel? If so, would a new table entry for such a material be sufficient?
Conclusion

7. The Sub-Committee is invited to consider appropr iate next steps to ensure that the provisions of the Model Regulations adequately addr ess the risks posed by the transport of crude oil. Based on the feedback received at thi s session, the experts from Canada and the United States of America would be willing t o prepare specific proposals for consideration at a future session.

_______________34

Appendix 4



### Test methods used to evaluate selected Bakken Crude Oil Characteristics

1. Flashpoint (Note: Some reported using the methods referenced i n §173.120(c).)

- ASTM D56 Standard Test Method for Flash Point by Ta g Closed Cup Tester

- ASTM D93 Standard Test Methods for Flash Point by P ensky-Martens Closed Cup
Tester

- ASTM D3278 Standard Test Methods for Flash Point of Liquids by Small Scale Closed-Cup Apparatus

2. Initial boiling point (Note: Some reported using the methods referenced i n §173.121(a)(2).)

- ASTM D86 Standard Test Method for Distillation of P etroleum Products at Atmospheric Pressure

- ASTM D1160 Standard Test Method for Distillation of Petroleum Products at Reduced Pressure

- ASTM D2887 Standard Test Method for Boiling Range D istribution of Petroleum Fractions by Gas Chromatography

- ASTM D5134 Standard Test Method for Detailed Analys is of Petroleum Naphthas through n-Nonane by Capillary Gas Chromatography

- ASTM D7169 Standard Test Method for Boiling Point D istribution of Samples with Residues Such as Crude Oils and Atmospheric and Vac uum Residues by High Temperature Gas Chromatography

3. Vapor pressure

- ASTM D2879 Standard Test Method for Vapor Pressure- Temperature Relationship and Initial Decomposition Temperature of Liquids by Isoteniscope

- ASTM D5191 Standard Test Method for Vapor Pressure of Petroleum Products (Mini Method)

4. Flammable gas content

- ASTM D-5134 Standard Test Method for Detailed Analy sis of Petroleum Naphthas through n-Nonane by Capillary Gas Chromatography

- ITM 6008 Light ends analysis by Gas Chromatography

- IP 344 Determination of light hydrocarbons in stabi lized crude oils - Gas chromatography method

5. Hydrogen sulfide content

- ASTM D5705 Standard Test Method for Measurement of Hydrogen Sulfide in the Vapor Phase Above Residual Fuel Oils35

- IP 507: Determination of boiling range distribution by gas chromatography method - Part 2: Heavy distillates and residual fuels

- UOP163 Hydrogen Sulfide and Mercaptan Sulfur in Liq uid Hydrocarbons by Potentiometric Titration

6. Corrosivity to metal

- NACE TM172 Standard Test Method - Determining Corro sive Properties of Cargoes in Petroleum Product Pipelines36

Appendix 5

Guide 128 from the 2012 ERG



## GUIDE 128 F lammable L iquids (N on -P olar /W ater -I mmiscible ) POTENTIAL HAZARDS FIRE OR EXPLOSION • HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. • Vapors may form explosive mixtures with air. • Vapors may travel to source of ignition and flash back. • Most vapors are heavier than air. They will sprea d along ground and collect in low or confined areas (sewers, basements, tanks). • Vapor explosion hazard indoors, outdoors or in se wers. • Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. • Runoff to sewer may create fire or explosion haza rd. • Containers may explode when heated. • Many liquids are lighter than water. • Substance may be transported hot. • For UN3166, if Lithium ion batteries are involved , also consult GUIDE 147. • If molten aluminum is involved, refer to GUIDE 16 9.

HEALTH • Inhalation or contact with material may irritate or burn skin and eyes. • Fire may produce irritating, corrosive and/or tox ic gases. • Vapors may cause dizziness or suffocation. • Runoff from fire control or dilution water may ca use pollution. PUBLIC SAFETY • CALL EMERGENCY RESPONSE Telephone Number on Shipp ing Paper first. If Shipping Paper not available or no answer, refer to appropriate teleph one number listed on the inside back cover. • As an immediate precautionary measure, isolate sp ill or leak area for at least 50 meters (150 feet) in all directions. • Keep unauthorized personnel away. • Stay upwind. • Keep out of low areas. • Ventilate closed spaces before entering.

PROTECTIVE CLOTHING • Wear positive pressure self-contained breathing a pparatus (SCBA). • Structural firefighters’ protective clothing will only provide limited protection.

EVACUATION Large Spill • Consider initial downwind evacuation for at least 300 meters (1000 feet). Fire • If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all dire ctions; also, consider initial evacuation for 800 meters (1/2 mil e) in all directions. EMERGENCY RESPONSE FIRE CAUTION: All these products have a very low flash p oint: Use of water spray when fighting fire may be inefficient. CAUTION: For mixtures containing alcohol or polar s olvent, alcohol-resistant foam may be more effective. Small Fire • Dry chemical, CO 2 , water spray or regular foam. Large Fire • Water spray, fog or regular foam. • Do not use straight streams

. • Move containers from fire area if you can do it w ithout risk. Fire involving Tanks or Car/Trailer Loads • Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. • Cool containers with flooding quantities of water until well after fire is out. • Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. • ALWAYS stay away from tanks engulfed in fire. • For massive fire, use unmanned hose holders or mo nitor nozzles; if this is impossible, withdraw from37

area and let fire burn.

SPILL OR LEAK

• ELIMINATE all ignition sources (no smoking, flare s, sparks or flames in immediate area). • All equipment used when handling the product must be grounded. • Do not touch or walk through spilled material. • Stop leak if you can do it without risk. • Prevent entry into waterways, sewers, basements o r confined areas. • A vapor suppressing foam may be used to reduce va pors. • Absorb or cover with dry earth, sand or other non -combustible material and transfer to containers. • Use clean non-sparking tools to collect absorbed material. Large Spill • Dike far ahead of liquid spill for later disposal

. • Water spray may reduce vapor; but may not prevent ignition in closed spaces.

FIRST AID • Move victim to fresh air. • Call 911 or emergency medical service. • Give artificial respiration if victim is not brea thing. • Administer oxygen if breathing is difficult. • Remove and isolate contaminated clothing and shoe s. • In case of contact with substance, immediately fl ush skin or eyes with running water for at least 20 minutes. • Wash skin with soap and water. • In case of burns, immediately cool affected skin for as long as possible with cold water. Do not rem ove clothing if adhering to skin. • Keep victim warm and quiet. • Ensure that medical personnel are aware of the ma terial(s) involved and take precautions to protect themselves38

Appendix 6

Glossary of Terms and Acronyms

AFPM means the American Fuel & Petrochemical Manufacture rs.

DOT means U.S. Department of Transportation.

ERG means the Emergency Response Guidebook produced by PHMSA in cooperation with the governments of Canada and Mexico and used throughou t North America as the basis for the initial response to a hazardous materials emergency

. Flashpoint means the lowest temperature at which a liquid or g as produces a concentration of vapor in air that may be ignited.

H 2 S means hydrogen sulfide.

HMR the Hazardous Materials Regulations in 49 CFR Parts 105 to 180.

IBP means initial boiling point.

OSHA means the Occupational Safety and Health Administr ation.

PHMSA means the DOT Pipeline and Hazardous Materials Adm inistration.

Packing Group means the degree of hazard assigned to materials su bject to the DOT HMR according to specified criteria. Hazard levels of Packing Group I (high), II (medium) and III (low) are possible.

RVP means Reid Vapor Pressure.

STEL means short term exposure limit for a specific substance in air. The value is commonly based on 15 minutes exposure.

TVP means True Vapor Pressure.

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