TECHNICAL SUPPORT DOCUMENT (UPDATED) 

FOR IMPORTS AND EXPORTS OF 

FLUORINATED GREENHOUSE GASES (GHGs), 

N2O, AND CO2 IN PRODUCTS: 

PROPOSED RULE FOR MANDATORY 

REPORTING OF GREENHOUSE GASES 

Office of Air and Radiation 

U.S. Environmental Protection Agency 

March 22, 2010 

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Contents

1. Source Description...............................................................................................................................................3

a. Total Inventory................................................................................................................................................5

2. Review of Existing Reporting Programs and Methodologies..............................................................................6

3. Types of Products Considered .............................................................................................................................6

4. Options for Reporting Threshold .........................................................................................................................7

5. Options for Monitoring Methods.........................................................................................................................8

6. Procedures for Estimating Missing Data..............................................................................................................9

7. QA/QC Requirements..........................................................................................................................................9

8. Options for Reporting Procedures........................................................................................................................9

9. References..........................................................................................................................................................10

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1. Source Description 

A variety of products containing fluorinated greenhouse gases (GHGs), sulfur hexafluoride (SF6), nitrous oxide 

(N2O), and carbon dioxide (CO2) are imported into and exported from the United States. 

HFCs are used as refrigerants in a wide range of air-conditioning and refrigeration equipment. In this application, 

HFCs serve as substitutes for ozone-depleting substances (ODSs), which are being phased out under the Montreal 

Protocol. Because some ODSs (i.e., HCFCs) are only beginning to be phased out, the use of HFCs in equipment 

such as window and residential air-conditioners is expected to grow very quickly over the next decade. Imports and 

exports of pre-charged equipment may grow as well. Although the quantities of chemical contained in each unit are 

small in absolute terms (i.e., a few pounds or less), they are more significant in CO2-equivalent terms, ranging up to 

eleven mtCO2e per unit for pre-charged commercial air-conditioners. This significance is due to the high GWPs of 

the HFCs. 

HFCs are also used as blowing agents during the manufacture of foams. Open-cell foams are assumed to emit 100 

percent of the blowing agent in the year they are manufactured, whereas closed-cell foams emit only a fraction of 

their total HFC content upon manufacture. Foam products that are closed-cell and imported or exported as a 

finished foam product therefore have potential to emit the blowing agent remaining in the foam after manufacture. 

Closed cell foams that are imported or exported include: polyurethane (PU) rigid foam used as insulation in 

domestic refrigerators and freezers; commercial refrigeration foam; PU rigid sandwich panel continuous and 

discontinuous foam; extruded polystyrene (XPS) sheet foam; and XPS boardstock foam. 

SF6 is used as an electrical insulator and arc-quenching gas in electrical transmission equipment, including circuit 

breakers and gas-insulated substations. Again, the quantities of SF6 in each unit are often small in absolute terms 

(around 14 pounds per circuit breaker), but are larger in CO2-equivalent terms (around 150 mtCO2e per circuit 

breaker). (Discussions with manufacturers of electrical equipment indicate that one-fifth of gas-insulated 

switchgear may be imported with a partial “holding” charge of about one ton of SF6, equivalent to 28,000 mtCO2e. 

However, the extent to which this occurs in practice is uncertain.) 

Products containing N2O may also be imported into or exported from the United States. N2O is used primarily in 

two major end-use applications—1) as a carrier gas with oxygen to administer more potent inhalation anesthetics 

and as an anesthetic in various dental and veterinary applications, and 2) as a propellant in pressure and aerosol 

products, the largest application being pressure-packaged whipped cream. As such, imported or exported products 

containing N2O may include pre-charged anesthetic equipment for medical applications and in aerosol cans such as 

pressure-packaged whipped cream products. Other potential products precharged with N2O may include fuel 

oxidizer canisters for auto applications and blowtorches containing N2O used by jewelers and others (Heydorn 1997; 

EPA 2008). 

Table 1-1 provides the number of refrigeration and air-conditioning (AC) units that are projected to be imported into 

and exported from the United States in 2010, as well as the total mtCO2e of HFC refrigerant projected to be inside 

the equipment in that year. This equipment may also include closed-cell foams, which are quantified in Table 1-2. 

The number of refrigeration and AC units imported or exported in 2010 was assumed to equal the number of units 

imported or exported in 2006. The refrigeration and AC units traded in 2006 were pre-charged with both HFCs and 

HCFCs. (HCFCs are ozone-depleting substances that are regulated under the Montreal Protocol and are exempt 

from the definition of fluorinated GHG.) However, by 2010 EPA expects that all imported or exported refrigeration 

and AC units will be precharged with HFCs, because many imports or exports pre-charged with HCFCs will not be 

permitted starting in that year. 

 

Table 1-1: Projected 2010 Imports and Exports of Refrigeration and AC Equipment Precharged with HFCs 

Product Number of 

Units Imported 

(2010)a

Estimated Total 

GHGs Imported 

(mtCO2e) (2010) 

Number of 

Units Exported 

(2010)a

Estimated Total 

GHGs Exported 

(mtCO2e) (2010) 

Dehumidifiers 109,393 28,945 14,427 3,817 

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Product Number of Estimated Total Number of Estimated Total 

Units Imported 

(2010)a

GHGs Imported 

(mtCO2e) (2010) 

Units Exported GHGs Exported 

(2010)a (mtCO2e) (2010) 

Window ACs 9,028,514 7,379,194 298,075 243,623 

Residential Unitary ACs 359,189 2,556,198 120,187 855,321 

Small Commercial ACs 10,702 121,842 56,975 648,660 

Packaged Terminal AC/Heat 

Pumps 

235,487 250,228 55,461 58,933 

Ice Makersb 27,292 90,473 22,446 74,408 

Mobile ACsc 2,345,000 2,868,096 2,345,000 2,868,096 

Refrigerated Appliances 9,382,646 1,762,530 1,867,901 350,885 

Small Retail Food 784,281 676,016 167,250 144,162 

Sources: U.S. Department of Transportation (2009) (Mobile ACs); U.S. Census Bureau (2009) (all other equipment types) a

Number of imports/exports in 2010 is set equal to reported imports/exports for 2006. 

b

Most recent data is for 2002; 2006 estimate is estimated by applying the percentage of new units (from Vintaging Model) 

supplied by imports/exports (from Census) in 2002 to the number of 2006 new units (from Vintaging Model). c

Motor vehicle import data excludes imports from Canada and Mexico. No export data from the U.S. DOT was available for this 

product, so exports were set equal to imports. This trade position is probably not the case. 

Table 1-2 provides the estimated amounts of foam containing HFCs and of electrical equipment containing SF6 that 

were imported into or exported from the United States in 2006, as well as the estimated total mtCO2e of fluorinated 

GHGs imported or exported inside these products in 2006. This table includes foams inside refrigerators. 

Refrigerant contained in these products is accounted for in Table 1-1. 

Table 1-2: 2006 Foam and Electrical Equipment Imports and Exports Containing Fluorinated GHGs 

Product Fluorinated 

GHG(s) 

Estimated 

Number of 

Units 

Imported 

(2006) 

Estimated 

Total GHG 

Imported 

(mtCO2e) 

(2006) 

Estimated 

Number of 

Units 

Exported 

(2006) 

Estimated 

Total GHG 

Exported 

(mtCO2e) 

(2006) 

XPS Boardstock Foama HFC-134a 20 MM bd-ft. 183,365 20 MM bd-ft. 183,365 

XPS Sheet Foama HFC-152a 2 MM bd-ft. 2,011 2 MM bd-ft. 2,011 

PU Rigid Foam: Domestic 

Refrigerationa HFC-245fa 36 MM bd-ft. 2,420,135 36 MM bd-ft. 2,420,135 

Commercial Refrigeration 

Foama HFC-245fa 5 MM bd-ft. 399,067 5 MM bd-ft. 399,067 

PU Rigid Foam: Sandwich 

Panelsa HFC-134fa 3 MM bd-ft. 20,708 3 MM bd-ft. 20,708 

Circuit Breakers (72.5 kV 

to 345 kV)b SF6 200 30,665 1,000 153,323 

Gas Insulated Substations 

(GIS) SF6 67 1,858,268 0 0 

Source: Russell (2008) (Foams); Bolin (2008) (Electrical Equipment) a

In the absence of detailed data, exports were assumed equal to imports. This is probably not the case. b

This product is the only size circuit breaker that is assumed to be imported or exported precharged with SF6. Larger equipment 

is not imported or exported with a full charge since they are assembled on site in the field; small equipment uses insulators other 

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than SF6.

a. Total Inventory 

The number of importers and exporters shipping products containing fluorinated GHGs varies depending on the gas 

and product in question. Based on conversations with multiple industry experts, EPA estimates that eight original 

equipment manufacturers are importing high voltage circuit breakers or gas insulated substations that contain a 

holding charge of SF6 (i.e., estimated as a charge of about 5 psig, which translates into approximately 20-25% of 

nameplate capacity). There are also 10 entities exporting high voltage circuit breakers, an upper bound estimate 

based on EPA’s knowledge of 10 equipment manufacturers operating in the U.S. It is estimated that there are 

approximately 50 entities importing and 25 entities exporting refrigeration and AC equipment containing a 

fluorinated GHG refrigerant and foam products containing a fluorinated GHG blowing agent. Entities trading precharged equipment and foam products are assumed to be distinct, although the possibility for overlap exists. 

Similarly, exporters are assumed to be distinct from and approximately half the number of importers (ICF 2008a). 

EPA estimates that annually, approximately 16 million mtCO2e of HFCs are imported in pre-charged refrigeration 

and AC equipment, three million mtCO2e of HFCs are imported in closed-cell foams, and two million mtCO2e of 

SF6 imported in pre-charged electrical equipment. EPA also estimates that there are approximately 5 million 

mtCO2e of HFCs exported in pre-charged refrigeration and AC equipment, three million mtCO2e of HFCs exported 

in closed-cell foams, and 150 thousand mtCO2e exported in pre-charged electrical equipment. 

Table 1-3 compares imports and exports of fluorinated GHGs in pre-charged equipment and foams to other U.S. 

supply flows of these gases, while Table 1-4 compares imports and exports in pre-charged equipment and foams to a 

bottom-up estimate of U.S. consumption of these gases from the Inventory of U.S. Greenhouse Gas Emissions and 

Sinks: 1990-2006. As shown in Table 1-3 and Table 1-4, imports in pre-charged equipment and foam are estimated 

to account for between 7 and 10 percent of the net U.S. supply or consumption of fluorinated GHGs, while exports 

in pre-charged equipment and foam are estimated to account for 3 to 4 percent of the U.S. net supply or 

consumption. 

Table 1-3: Imports and Exports of Pre-Charged Equipment and Foams as Share of U.S. Fluorinated GHG 

Supply (Top-Down, 2006) 

Supply Flow Quantity (mtCO2e) 

Domestic Production 350,000,000 

Imports in Bulk 110,000,000 

Exports in Bulk 175,000,000 

Imports in Pre-Charged Equipment, Foams 21,000,000 

Exports in Pre-Charged Equipment, Foams 8,400,000 

Net supply (all flows) 297,600,000 

Equipment, Foam Imports as Share of Net Supply 7% 

Equipment, Foam Exports as Share of Net Supply 3% 

 

Table 1-4: Imports and Exports of Pre-Charged Equipment and Foams as Share of U.S. Fluorinated GHG 

Consumption (Bottom-Up, 2006) 

Consumption Component Quantity (mtCO2e) 

Total U.S. Consumption (2006, US Inventory) 215,000,000 

Equipment, Foam Imports as Share of Consumption 10% 

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Equipment, Foam Exports as Share of Consumption 4% 

Although EPA does not have data on the amount of CO2 or N2O imported or exported in products (e.g., carbonated 

sodas and cans of whipped cream), the relatively small quantities of CO2 or N2O contained in each unit and the 

relatively low GWPs of these gases (compared to those of the fluorinated GHGs) imply that the CO2-equivalent 

quantities imported or exported are likely to be small both nationally and per entity. This conclusion is supported by 

the fact that 2006 production and bulk imports of CO2 and N2O were one percent or less of those of the fluorinated 

GHGs in CO2-equivalent terms (see Technical Support Documents EPA-HQ-OAR-2008-0508-012 and EPA-HQOAR-2008-0508-042.

2. Review of Existing Reporting Programs and Methodologies 

Protocols/guidance reviewed for this analysis include the 2006 IPCC Guidelines, Title VI of the Clean Air Act 

(CAA), Part 75 Appendix D (measurement requirements for oil and natural gas), the Toxic Release Inventory (TRI), 

the Toxic Substances Control Act (TSCA) Inventory Update Rule, and the Australian Commonwealth Government 

Ozone Protection and Synthetic Greenhouse Gas Reporting Program. 

These programs vary in their treatment of products containing chemicals whose bulk import or export must be 

reported. The Australian program requires reporting of all ODSs and GHGs imported in pre-charged equipment, 

including the type of equipment, the identity of the refrigerant, the number of pieces of equipment, and the charge 

size. However, the program does not cover the export of this equipment. The TSCA Inventory Update Rule 

requires reporting of chemicals contained in products if the chemical is designed to be released from the product 

when it is used (e.g., ink from a pen). EPA’s ozone protection regulations do not currently require reporting of 

ODSs contained in imported or exported equipment or other products; however, (1) EPA has prohibited the 

introduction into interstate commerce, including import, of certain non-essential products typically pre-charged with 

these chemicals, and (2) EPA has prohibited the sale or distribution in interstate commerce, including import, of 

equipment pre-charged with HCFCs (74 FR 66450, December 15, 2009). 

For the full review of existing programs, please refer to (EPA-HQ-OAR-2008-0508-054). 

3. Types of Products Considered 

In determining which products should be subject to reporting, EPA believes it is appropriate to consider three 

criteria: (1) the quantity of GHGs likely to be imported or exported in the product nationally and per importer or 

exporter, (2) the ease with which the GHG in the product can be identified, and (3) the ease with which the GHG in 

the product can be quantified. 

As noted above, the CO2-equivalent quantities of CO2 and N2O imported or exported in products are likely to be 

small both nationally and per entity due to the relatively small quantities of CO2 and N2O contained in each unit and 

the relatively low GWPs of these gases (compared to those of the fluorinated GHGs). EPA’s review of other 

protocols and guidance affecting imports and exports did not identify any programs that quantify or restrict trade of 

CO2 or N2O in products. 

As discussed above, the quantities of fluorinated GHGs imported or exported in equipment are potentially 

significant both overall and per product type. For example, EPA estimates that 7 million metric tons CO2e are 

imported inside pre-charged window air-conditioners. Other types of equipment that are imported or exported 

containing significant quantities of fluorinated GHGs include mobile air-conditioners, refrigerated appliances, 

residential air-conditioners, and gas-insulated switchgear. The identities and amounts of fluorinated GHGs 

contained in equipment are generally well known; this data is typically listed on the nameplate affixed to every unit. 

The information is also available in servicing manuals and other paperwork that the entity would be expected to 

have on file. 

Closed cell foams, such as polyurethane (PU) appliance foams (used to insulate refrigerators and freezers) and 

extruded polystyrene (XPS) insulation boardstock (used to insulate buildings), also contain significant amounts of 

fluorinated GHGs. Again, manufacturers and importers or exporters would generally be expected to be able to 

identify and quantify the amounts in their products. (The identities and quantities of chemical inside the foam 

directly affect its insulating capability.) Since many importers or exporters of refrigerators would already be 

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required to report based on the refrigerant contents of the equipment, the additional effort required to track and 

quantify the GHGs contained in the foam would probably not be excessively burdensome. 

4. Options for Reporting Threshold 

EPA evaluated a range of threshold options for imports or exports of fluorinated GHGs in products, including 

thresholds based on the quantity of chemical imported or exported (1,000; 10,000; 25,000; and 100,000 mtCO2e) 

and on the number of pieces of equipment or volume of foam imported or exported. Additionally, EPA considered 

setting no threshold (requiring reporting of all imports or exports), which is the approach used under the Australian 

Synthetic Greenhouse Gas Reporting Program. 

Table 4-1 and Table 4-2 present the total masses of HFCs and SF6, in mtCO2e, that EPA estimates are contained in 

imported and exported pre-charged equipment, both nationally and by entity. The amount of total gas imported or 

exported was estimated by summing the product of the average charge size (as detailed below) and the quantity of 

imports or exports (as detailed in Table 1-3 and Table 1-4) for each equipment type. Where products include foam 

as well as refrigerant (e.g., household refrigerators), the fluorinated GHG in the foam was also included. 

Information on the number of entities was obtained from ICF (2008a) for HFC equipment and from Phil Bolin 

(2008) for SF6 equipment. In the absence of entity-specific data, the analysis below assumes that each entity 

imports or exports the same quantity of HFC or SF6 equipment. 

In order to calculate an average CO2-equivalent charge size for each equipment type, data on gas-specific charge 

sizes were first collected from three separate sources, depending on the equipment type. For refrigeration and AC 

equipment, charge size estimates were taken from EPA’s Vintaging Model (VM) (EPA 2008). The average HFC 

density of each foam type was estimated based on engineering judgment (ICF 2008b). For SF6-containg equipment 

(i.e., circuit breakers and gas insulated substations), the average charge size was calculated using the assumption 

provided by Phil Bolin (2008) that the average shipping charge is 20 percent of the equipment’s total nameplate 

capacity. These data were then weighted by the percentage of new units in 2010 using the relevant gas, as estimated 

by EPA’s VM, for each equipment type. Finally, the charge sizes were converted in mtCO2e using SAR GWPs and 

summed to develop an average CO2-equivalent charge size for each equipment type. The numbers of pieces of 

equipment to trigger reporting at various thresholds is simply the threshold divided by this calculated average charge 

size. 

EPA believes that a threshold based on the total quantity of chemical imported or exported is likely to be more 

practical and equitable than one based on the number of pieces of equipment or volume of foam imported or 

exported. This conclusion is based on the fact that entities may import or export multiple types of equipment and/or 

foam, which may contain different quantities of refrigerant and/or blowing agent per unit. If a threshold based on 

numbers of pieces of equipment were established, it could exclude entities that imported or exported large quantities 

of GHGs spread out among multiple types of equipment. Alternatively, it could require a complicated formula to 

prevent such exclusions. 

Based on the assumptions outlined above, all importers or exporters of equipment pre-charged with HFCs or SF6

would be required to report all imports or exports of this equipment under all thresholds considered. In reality, 

imports or exports are likely to be concentrated among a relatively small number of entities, decreasing the number 

of reporters and the amount reported. This is the pattern that EPA has seen for bulk imports of fluorinated GHGs, 

where approximately 40 percent of the importers import almost 100 percent of the imports at an import threshold of 

25,000 mtCO2e (Technical Support Document EPA-HQ-OAR-2008-0508-042). In general, as thresholds decrease, 

smaller entities representing successively smaller shares of total national imports or exports are required to report. 

The drawback of requiring reporting of all imports or exports (i.e., setting no threshold) is that it could substantially 

increase the burden of the rule without substantially increasing the quantity of imports or exports reported. 

Table 4-1: Import Threshold Summary: Masses of GHGs that would be covered by the Various Thresholds 

Total Amount Meeting Threshold (mtCO2e) 

Product Type Imports 

(mtCO2e) 

Number 

of 

Importers 

GHG per 

Importer 

(mtCO2e) 1,000 10,000 25,000 100,000 

Pre-charged 

Equipment 

HFC 15,733,523 50 314,670 15,733,523 15,733,523 15,733,523 15,733,523 

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Total Amount Meeting Threshold (mtCO2e) 

Product Type Imports 

(mtCO2e) 

Number GHG per 

of Importer 

Importers (mtCO2e) 1,000 10,000 25,000 100,000 

Refrigeration / 

AC Equipment 

SF6 Electrical 

Equipment 1,888,932 8 236,117 1,888,932 1,888,932 1,888,932 1,888,932 

Closed-cell Foams 3,025,285 50 60,506 3,025,285 3,025,285 3,025,285 

Table 4-2: Export Threshold Summary: Masses of GHGs that would be covered by the Various Thresholds 

Total Amount Meeting Threshold (mtCO2e) 

Product Type Exports 

(mtCO2e) 

Number 

of 

Exporters 

GHG per 

Exporter 

(mtCO2e) 1,000 10,000 25,000 100,000 

Pre-charged 

Equipment 

HFC 

Refrigeration / 

AC Equipment 

5,247,905 25 209,916 5,247,905 5,247,905 5,247,905 5,247,905 

SF6 Electrical 

Equipment 153,323 10a Variesb 153,323 107,326 0 0 

Closed-cell Foams 3,025,285 25 60,506 3,025,285 3,025,285 3,025,285 3,025,285 a

Includes five importers that also export.

b

Based on data from Rich York (2008), five manufacturers are assumed to account for a majority of the exports.

5. Options for Monitoring Methods 

Options for tracking imports and exports of products include reporting the total amount of each fluorinated GHG 

imported or exported inside the products and/or the quantity of the product imported or exported (e.g., number of 

pieces of equipment), along with information on the identity and quantity of the fluorinated GHG in each unit or 

piece. EPA has reviewed existing reporting programs and methodologies that take one or both of these approaches, 

as described above. 

The quantities of fluorinated GHGs contained in imported or exported products could be reported by chemical in 

tons or in mtCO2e. Reporting in tons of chemical would provide more transparency and reduce mistakes such as 

arithmetic errors or the use of inappropriate GWPs. Entities importing equipment that contained both a fluorinated 

GHG refrigerant and a foam blown with a fluorinated GHG (e.g., household refrigerators) could separately report 

these GHGs (which are generally different). Similarly, total exports of chemical actually contained in exported 

equipment, foams, or other products could be reported by exporters, by chemical in tons or mtCO2e. 

The equation below could be used to estimate each entity’s imports or exports of each fluorinated GHG inside 

equipment or foams: 

= ∑tNSI tt 001.0**

where, 

I is the total amount of the fluorinated GHG imported or exported by the entity annually (metric tons) 

t is the type of equipment/foam containing the fluorinated GHG 

St is the shipping charge per unit of equipment or foam type t 

Nt is the number of units of equipment or foam type t imported or exported annually 

0.001 is the factor converting kg to metric tons 

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As is the case for bulk imports, any trans-shipments (i.e., products containing GHGs that originate in a foreign 

country and enter the United States en route to an ultimate destination in another foreign country) could be exempt 

from reporting. Similarly, entities could report their imports or exports on the corporate level. 

6. Procedures for Estimating Missing Data 

A complete record of all measured parameters used in the GHG emissions calculations would be required; no data 

should be missing as the data are required for importing and exporting in the United States. 

7. QA/QC Requirements 

Options for QA/QC requirements includes reviewing inputs to the annual submission against the import and export 

transaction records to ensure that the information submitted to EPA is being accurately transcribed as the correct 

chemical or blend in the correct units and quantities (metric tons). 

8. Options for Reporting Procedures 

Along with their formal report, entities could be required to submit the following supplemental data to document 

and verify their import or export estimates: 

• Quantities of products imported or exported, in appropriate units; 

• The name of the fluorinated GHG, charge size (holding charge, if applicable), and number imported or 

exported for each type of equipment; and 

• The name of the fluorinated GHG, and the quantity imported or exported (cu. ft and kg/ft2 or tons) for each 

type of foam. 

Importers could be required to keep the following records to document and verify their import estimates: 

• The information reported (as indicated above); 

• The port of entry through which the fluorinated GHGs passed; 

• The country from which the imported fluorinated GHGs were imported; 

• The importer number for the shipment; 

• A copy of the bill of lading for the import; 

• The invoice for the import; and 

• The U.S. Customs entry form. 

Along with their formal report, exporters could be required to submit the following supplemental data to document 

and verify their export estimates: 

• Quantities of products exported, in appropriate units; 

• The name of the fluorinated GHG, charge size (holding charge, if applicable), and number exported for 

each type of equipment; and 

• The name of the fluorinated GHG, and the quantity exported (cu. Ft and kg/ft2 or tons) for each type of 

foam. 

Exporters could be required to keep the following records to document and verify their export estimates: 

• The information reported above; 

• The names and addresses of the exporter and the recipient of the exports; 

• The exporter’s Employee Identification Number; 

• The date on which, and the port from which, the products containing the fluorinated GHGs were exported 

from the United States or its territories; 

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• The country to which the products containing the fluorinated GHGs were exported; and 

• The invoice for the export. 

Persons who transship products containing fluorinated GHGs could be required to maintain records that indicated 

that the products originated in a foreign country and was destined for another foreign country and did not enter into 

commerce in the United States. 

9. References 

Phil Bolin (2008) Personal Communication between Phil Bolin of Mitsubishi and Paul Stewart of ICF International, 

June 24, 2008. 

Heydorn, B. (1997) “Nitrous Oxide—North America.” Chemical Economics Handbook, SRI Consulting. May 1997. 

EPA (2008) “Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2006”. 

ICF (2008a) Potential Importers and Exporters of Pre-Charged Refrigeration and Air Conditioning Equipment 

Memorandum, June 18, 2008. 

ICF (2008b) Personal Communication between Robert Russell of RJR Consulting and Marian Van Pelt of ICF 

International, June 13, 2008. 

Robert Russell (2008) Personal Communication between Robert Russell of RJR Consulting and Marian Van Pelt of 

ICF International, April 23, 2008. 

U.S. Census Bureau (2009) U.S. International Trade Commission (USITC) Data Web. Available at 

<http://dataweb.usitc.gov>. Year 2006 data Accessed October 2009. 

U.S. Department of Transportation (2009) National Transportation Statistics 2009. Bureau of Transportation 

Statistics. Available at: <http://www.bts.gov/publications/national_transportation_statistics/pdf/entire.pdf> 

Rich York (2008) Personal Communication between Rich York of ABB and Paul Stewart of ICF International, June 

24, 2008. 

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