September 2016



## 8

- Hour O zone

State Implementation Plan Emission Inventory

Supplemental DocumentationSeptember 2016

1 I. Introduction

This document describes the sources and methods used to develop California’s

2012 summer emission inventory used in the 8

- Hour Ozone State Implementation
Plan (SIP or Plan ) Emission Inventory Submittal (transmitted July 17, 2014)

. The Air Resources Board (ARB ) works continuously with the local air districts to collect information and conduct research to improve California’s emission inv entories. During development of this inventory submittal , ARB and d istrict staff conducted a thorough review of the 2012 inve ntory to ensure that the emission estimates reflected accurate reports for point sources, and that estimates for area

- wide and
mobile sources were based on the latest available models and methodologies.

The United States Environmental Protection Agency (U.S. EPA) establishes requirements pertaining to emission inventories that must be included as part of the SIP submittal package. For an o zone p lan, the regulations require that the emission inventory con tain emissions data for the two precursors to ozone formation: nitrogen oxides (NOx) and volatile organic compounds (VOCs).

Emission Inventory Overview

An emission inventory is a critical tool in the evaluation of air pollution. In simple terms, an emissi on inventory is a systematic listing of the sources of air pollution along with the amount of pollution emitted from each source or category over a given time period. Source categories include stationary (point and area

- wide ), mobile (on

- and off

- road), a nd natural sources. Emission inventories are an estimate of the amount of air pollution that is released into the environment. They are not measurements of ambient concentrations.

Emission inventories are fundamental components of an air quality plan. They serve as a primary input to air quality modeling use d in attainment demonstrations, provide the emissions data used for developing control strategies , and serve as a means to track progress in meeting the emission
reduction commitments.

Quality Assura nce and Quality Control

ARB has established a quality assurance and quality control (QA/QC) process employed by ARB and air district staff to ensure the integrity and accuracy of the emission inventories used in the development of air quality plans. QA/QC occurs at the various stages of SIP emission inventory development. Base year emissions are assembled and maintained in the California Emission Inventory Development and Reporting System (CEIDARS). ARB inventory staff works with air districts, which are responsible for developing and reporting point source emission estimates, to verify these data are accurate. The locations of point sources, including stacks, are checked to ensure they are valid. Area

- wide source emission estimates are developed by ARB staff as well as some air districts. The methodologies for estimating these are reviewed by ARB andSeptember 2016

2 district staff before their inclusion in the emission inventory. Additionally, CEIDARS is designed with automatic system checks to prevent errors such as double counting of emission sources. The system also makes various reports available to assist staff in their efforts to identify and reconcile anomalous emissions. Mobile categories are verified with ARB mobile source staff for consistency with the on

- r oad and off

- road emission models.

Base Year Selection

The base year inventory is an essential element of an air quality p lan that forms the basis for all future year projections and also establishes the emission levels against which progress in emission r eductions will be measured. U.S. EPA regulations establish that an inventory base year should be comprehensive, accurate, and current for all actual emissions. U.S. EPA establishes guidance on which year to select as the base year. They would prefer that states use the 2011 National Emissions Inventory (NEI), however, they allow a different year to be selected if justified by the state. At the time the base year inventory was required, ARB wanted a consistent inventory across the state. ARB worked with the local districts to come up with a base year inventory. The South Coast district typically aligns their base year inventory with their MATES data collection period. Since South Coast planned to use 2012 data consistent with MATES and
ARB wanted consis tency across the state, 2012 was selected as the base year.

Planning inventories typically include a nnual as well as seasonal (summer and winter) emission estimates . Annual emission inv entories represent the total emissions over an entire year (tons per year), or the daily emissions produced on an average day (tons per day). Seasonal inventories account for temporal activity variations throughout the year, as determined by category

- spec ific temporal profiles. Since o zone concentrations tend to be highest during the

summer months, the emission inventory used in the Plan is based on the

summer season (May through October)

.September 2016

3 II. Emission Inventory Components

A summary of the components that make up the Ozone SIP base year e mission inventory is presented in the following sections

. These include mobile (on

- and off

road) sources and stationary (point and area

- wide) sources. Natural sources are not included in a SIP emission inventory.

Mobile Source Emissions

ARB develops the emission inventory for the mobile sources using various computer models. These models account for the effects of various adopted regulations, technology types, fleet turnover, and seasonal conditions on
emissions. Mobile sources in the emission inventory are composed of both on

road and off

- road sources, describe d in the sections below.

On

- Road Mobile Source Emissions

On

- road motor vehicle emissions from cars, light and heavy

- duty trucks, motorcycles, buses, and motor home s in California are estimated using ARB’s Emission Factors (EMFAC) model. Emissions are calculated as the product of a population of vehicles, the number of miles each vehicle travels, and emission rates. Emission rates assume regional speed
distribution s, regional temperature and relative humidity profiles by hour of day, and category specific cumulative mileage accrual of the vehicle for a given calendar year.

Vehicle populations are estimated using registration data from the Department of Motor Vehicle s (DMV) . R egistration data from the year

2012 w ere used to update the populations in each vehicle class and geographic area.

The model contains default speed distributions and estimated vehicle
miles traveled ( VMT ) as a function of vehicle population from DMV and mileage accrual rates from the Bureau of Automotive Repair Smog Check

program. This methodology involves matching DMV registration information to Smog Check data from the Bureau of Automotive Repair
and us ing vehicle identification number (VIN) decoders to interpret registration data.

The on

- road mobile emissions inventory used in this submittal reflect recent updates to the EMFAC 2011 activity parameters. These updates include vehicle population and activ ity using 2012 DMV data, vehicle sales and survival rate estimates, fuel sales from Board of Equalization, and updates to mileage accrual rates using Smog Check data. The default VMT regional allocations have been adjusted using the 2012 National Transport ation Atlas Database.September 2016

4 The model also reflects the emissions benefits of ARB’s recent rulemakings including ARB’s 2010 Truck and Bus Regulation, Pavley Clean Car Standards, and the Low Carbon Fuel standard.

Additional information regarding the EMFAC model is available at: http://www.arb.ca.gov/msei/msei.htm

Off

- Road Mobile Source Emissions

Emissions from off

- road sources such as locomotives, ships, industrial and construction equipment, and recreational v ehicles were estimated using a suite of category

- specific models. Many of these models were developed to support recent regulations, including in

- use off

- road equipment, ocean

- going vessels and others. Where category

- specific models were not yet develope d, the OFFROAD2007 model was used. The following sections describe the off

- road mobile source categories in
more detail.

Aircraft

Aviation related emissions were reported for 2012 by the local air districts. Emission estimates span the landing and take

- o ff cycle
and are calculated using FAA’s EDMS model. Most aircraft emissions are reported as point sources but some districts have provided area source methodologies which are available at: http://www.arb.ca.gov/ei/areasrc/districtomobilsrcaircraft.htm

Ocean Going Vessels

The Ocean

- Going Vessel (OGV) inventory represents commercial vessels greater than or equal to 400 feet in length or 10,000 gross tons; or propelled by a marin e compression ignition engine with a displacement of greater than or equal to 30 liters per cylinder. The ARB emission inventory includes all OGV emissions occurring
within 100 nautical miles of the California coastline.

Vessel port calls were obtained fr om a database maintained by the California State Lands Commission (SLC) in 2007. This database includes vessel identification, port of arrival, previous port, next port, and date and time of arrival. The Lands Commission compiles
this database from marine exchanges and port authorities
statewide.

Vessel specific hoteling times and berth locations were obtained from port officials responsible for ship docking, or wharfingers, in Los Angeles, Long Beach, Oakland, San Diego, San Francisco and
Hueneme. These d ata were reconciled with the port call data from
the SLC.September 2016

5 Emission factors for OGVs vary by pollutant, operating mode (transit, maneuvering, or hoteling), engine type (main engine/slow speed, main engine/medium speed, or auxiliary/medium speed),
and fuel t ype (heavy fuel oil or marine distillate) for main and auxiliary engines using a methodology defined by Starcrest Consulting Group in 2007. Emission factors were updated for the 2012 inventory to incorporate tier

- weighted control factors.

The ocean going vessel inventory accounts for new information related to goods movement activity. This is based on growth projections from the Federal Highway Administrations Freight Analysis Framework model and supported by other forecasts done
for the S an Pedro Bay Ports.

Additional information on this methodology is available at: http://www.arb.ca.gov/regact/2011/ogv11/ogv11appd.pdf

Commercial Harbor Craft

Commercial Harbor Craft ( CHC) are grouped into nine vessel types, including ferry and excursion vessels, tow boats, tug boats, pilot vessels, work boats, crew and supply vessels, commercial fishing vessels, charter fishing vessels, and other.

Vessel population data were collecte d from various sources, including the U.S. Coast Guard, the California Department of Fish and Game registration data, the ARB Harbor Craft Survey, and information from recent emission inventory estimates generated for the Port of Los Angeles. Vessel and e ngine profiles, including vessel and engine type, age, size, annual hours of operation, and annual fuel use were developed based on the ARB survey

Vessel and engine data were reported to ARB by vessel operators in compliance with ARB’s 2007 Commercial Harb or Craft Regulation. Staff updated the crew and supply vessel emissions inventory using 2009 reporting data and developed barge and dredge vessel emissions inventory using the 2009 survey
information.

Additional information on this methodology is availabl e at: http://www.arb.ca.gov/regact/2010/chc10/appc.pdf

Recreational Boats

Recreational Boats is a broad category of marine vessels that includes gasoline powered spark

- ignition marine watercraft and
diesel

- powered marine watercraft. The PC2014 model was developed by ARB to estimate emissions from recreationalSeptember 2016

6 watercraft. Popul ation, activity, and emission factors were reassessed using surveys, registration information, and emissions testing.

In 2009, ARB funded a California State University Sacramento (CSUS) phone survey of over 1,123 respondents. Staff used the
results of the survey to estimate the annual activity as well as the spatial allocations for operation and storage for recreational
watercraft.

ARB updated exhaust emissions factors based on ARB marine engine certification data. Evaporative emissions factors were also

u pdated based on actual ARB in

- house testing.

Additional information on this methodology is available at: http://www.arb.ca.gov/regact/2015/simw2015/simw15appj.pdf

Off

- road Recreat

ional Vehicles

Off

- highway Recreational Vehicle s (OHRVs) are integrated into a single regulatory category including off

- road motorcycles (OMC),
all

- terrain vehicles (ATV), off

- road sport vehicles, off

- road utility vehicles, sand cars, and golf carts. ARB has developed an emissions inventory model, RV2013, to estimate emissions generated by OHRVs in each region of the State. This inventory revision builds on previous ARB assessments, and contains updates to vehicle population, activity (hours/year or miles/ year), annual vehicle sales, emission factors, technology change from carbureted to fuel injected engines, as well as the change in the population split between two and four stroke engines.

California Department of Motor Vehicle (DMV) registration data

pr ovided detailed information on the total population and model year distribution of that population for each calendar year. The database also allows estimates of vehicles that are actively used as well as vehicles in storage at households. Staff used the D MV registration data to reevaluate the projected lifecycle of each vehicle type, and to estimate the expected total life, half

- life (or useful life), and year

- to

- year survival rate by vehicle type.

Activity was estimated from a 2009 ARB

- funded CSUS phone

s urvey. Staff corroborated the results of the survey with other data sources to develop estimates for OHRV use by age and vehicle type.

Staff developed emission factors based on certification data, vehicle testing, and other testing and analysis. Update s in cludeSeptember 2016

7 new evaporative emission factors based on evaporative test data for diurnal, resting, and hot soak emissions.

Exhaust emission factors used in RV2013 are consistent with OFFROAD2007 and based on certification data and adopted
exhaust emissions stand ards. In 2003, ARB contracted with Automotive Testing Laboratory for testing of evaporative emissions from OHRVs using a Sealed Housing for Evaporative Determination (SHED).

Additional information on this methodology is available at: http://www.arb.ca.gov/regact/2013/ohrv2013/ohrvattachc.pdf

Fuel Storage and Handling

In 2004, ARB staff contracted with the California State University, Sacramento to conduct two portable fuel containe r (PFC) surveys. The two surveys, Analysis of 2004 California Household Portable Fuel Container Survey (September 2004) and Analysis of the 2004 California Commercial Portable Fuel Container Survey (January 2005) estimated the number of PFCs and the penet ration rate of compliant PFCs. In addition, ARB staff quantified the emissions that occur when the PFCs are vented prior to fueling. These data are included in the report Quantification of Vent Emissions from Portable Fuel Containers Prior to Fueling (May 2005). Details regarding the proposed emissions adjustments can be found in the report Revised California’s Portable Gasoline Container Emissions Inventory (May 2005).

Additional information on this methodology is available at: http://www.arb.ca.gov/regact/pfc/2005/isor.pdf

Farm Equipment

The agricultural equipment inventory includes a wide variety of farm equipment including tractors, harvesters, loaders, and cotton pickers. In 2009, the C alifornia State University, Fresno Foundation conducted a voluntary survey of agricultural operations throughout California in order to update the emission inventory for
off

- road mobile agricultural equipment. This survey collected data on population, oper ational characteristics, and activity of off

- road mobile agricultural equipment. The survey also included questions about the types and amounts of commodities produced.

Off

- road farm equipment emissions were updated as part of the In

Use Off

- Road Diesel F ueled Fleets regulation development

process. The updated inventory relies on newly available information from statewide surveys, economic assessments andSeptember 2016

8 fuel analyses. The survey analysis resulted in an update to the age
distribution of the statewide fl eet.

The detailed data on California farm practices was combined with statewide data on agricultural fuel use from the California State Board of Equalization and United States Department of Agriculture data on farm equipment to revise equipment population s, activity, load factors, and turnover practices.

The In

- Use Mobile Agricultural Equipment Regulation Survey is
available at http://www.arb.ca.gov/ag/agtractor/agsurvey.htm

Off

- road Equipment

ARB’s off road equipment category spans a wide range of equipment types, including transportation refrigeration units, construction and mining equipment, airport ground support equipment, oil drilling and workover rigs, and cargo handling equip ment.

ARB updated this inventory in 2010 to support the analysis for
amendments to the In

- Use Off

- Road Diesel Fueled Fleets Regulation.

Transport Refrigeration Units

Transport refrigeration units (TRUs) are diesel

- powered refrigeration units that are in stalled on vehicles used in transporting produce, meat, dairy products, and other perishable goods. TRUs are found on refrigerated vans, trucks, trailers, railroad cars and containers.

The original inventory was completed in 2003 to support
ARB’s TRU Airb orne Toxic Control Measure (ATCM) which was adopted in February 2004. Under the TRU ATCM, owners of TRUs based within California are required to report to ARB’s Equipment Registration Reporting (ARBER) Database. Data from ARBER were used as a primary inp ut for the population and age distribution of the TRUs

This inventory relies on emission factors and deterioration
rates from OFFROAD2007.

The inventory also reflects updates to activity, population, growth and turn

- over data, and emission factors develope d to support the 2011 amendments to the Airborne Toxic
Control Measure for In

- Use Diesel

- Fueled Transport Refrigeration Units.September 2016

9 Additional information on this methodology is available at: http://www.arb.ca.gov/regact/2011/tru2011/truisor.pdf

Drill Rigs

Oil Drilling and Workover Rig emissions are estimated by several equipment types and horsepower categories. These emissions are estimated using ARB’s OFFROAD2007
model. OFFROAD2007 uses a verage horsepower and engine load factors obtained from the Power Systems Research (1996) database along with equipment population, activity, and useful life based on data from ARB’s Off

- Road Diesel Equipment Survey in 2005.

Additional information on this methodology is available at: http://www.arb.ca.gov/regact/2010/offroadlsi10/offroadappd. pdf

Cargo Handling Equipment

This category estimates emissions from diesel

- fueled cargo

h andling equipment (CHE) at California's ports and intermodal rail yards. Cargo handling equipment is used to transfer goods or perform maintenance and repair activities and includes equipment such as forklifts, yard trucks, cranes, top and side handlers, a nd loaders.

As part of ARB’s 2006 Cargo Handling Equipment Regulation, fleet owners and operators of CHE are required to submit information to ARB regarding equipment populations and hours of use. In 2006 and 2009, the Starcrest Consulting Group conducted a study on engine load for yard trucks cranes operating at the Ports of Los Angeles and Long Beach, and San Diego. ENVIRON conducted a similar study resulting in an emissions inventory
for the Port of Oakland in 2005

As part of the rail yard emission redu ction program, health
risk assessments were initiated in 2005 to determine the relative risk of exposure to diesel particulate matter in the proximity of 17 intermodal rail yards. As part of the assessment, activity data were collected for over 400 pieces of cargo handling equipment.

The CHE inventory relies on emission factors and
deterioration rates from OFFROAD2007. These emission factors are composed of zero

- hour emission rates, deterioration rates and useful life assumptions.September 2016

10 The growth factors used t o estimate cargo handling equipment emissions in future years was based on growth
factors from ARB’s Ocean

- Going Vessel inventory for container, bulk, general and reefers vessels.

Additional information on this methodology is available at: http://www.arb.ca.gov/regact/2011/cargo11/cargoappb.pdf

Trains

The methodology and assumptions used for estimating locomotive
emissions is based on the Booz

- Allen Hamilton’s Locomotive
Emission Stud y report in 1992. Emission factor s reflecting locomotive operations in California were developed by Southwest Research Institute along with various engine manufacturers such as General Electric (GE) and Electro

- Motive Diesel (EMD).
Locomotive fleet and o peration profiles were obtained from the Atchison Topeka Santa Fe and Union Pacific railroad companies using Train Performance Calculation data and actual event
recorder data.

The Booz

- Allen Hamilton analysis projected future rail traffic as a
function of population and economic growth in the state. This includes industrial production and railroad statistics from the
Association of American Railroads. Staff also reflected the effects of the goods movement from ports in California on locomotive traffic
lev els as well as emission controls resulting from the existing memorandum of understanding. The locomotive inventories also reflect the 2008 U.S.EPA locomotive regulations and adjustments due to economic activity.

Additional information on this methodology is available at: http://www.arb.ca.gov/msei/categories.htm#loco_categorySeptember 2016

11 Stationary Sources

The following reflects methods for developing ARB’s stationary source inventory. The stationary source inventory is composed of point sources and area

- wide
sources. Point source estimates are reported annually by the local air districts,
which are respon sible for working with facility operators to com pile estimates.
These methods include source testing, direct measurement by continuou s emissions monitoring systems , or engineering calculations.

The remaining a rea

- wide sources, including aggregated point s ources

, are estimated using various models and methodologies. Emissions for these categories are estimated by both ARB and the local districts. Area

- wide sources include categories where emissions take place over a wide geographic area

, such as consumer products . Area

- wide sources als o include smaller point

sources , such as gasoline dispensing facilities and residential water heaters that are not inventoried individually, but are estimated as a group and reported as a single source category. The area

- wide emission inventory categories are
described below.

Point Source Emissions

Food and Agricultural Processing

Emissions from the Food and Agricultural Processing category
include emissions from stationary fuel combustion sources in the agricultural and food processing sectors. Most of these emissions are reported as point sources; however, the exhaust emissions from agricultural irrigation pumps are estimated from a model developed by ARB staff . Air districts with significant irrigated agricultural acreage provided estimates of the population and emissions from stationary and mobile diesel

- fueled agricultural irrigation pumps. These data were reconciled with equipment population estimates from the 2003 US Department of Agriculture
Farm and Ranch Irr igation Survey (FRIS). The inventory also reflects the number of pumps that have been replaced to date under the Carl Moyer Program.

Estimation of the population and emissions from agricultural engines is described in an April 30, 2003 California Air Reso urces Board (ARB) memorandum entitled “ Updated Statewide Population and Emission Inventory for Diesel

- Fueled Agricultural Irrigation Pumps”. The stationary diesel engine inventory is based upon reconciliation of district permit data for selected districts and Power Systems Research (PSR) data for all districts.

Emission factors are taken from ARB’s OFFROAD model and areSeptember 2016

12 based on actual source tests of agricultural irrigation pump engines.

Additional information on this methodology is available at: http://www.arb.ca.gov/regact/agen06/attach2.pdf

Other Fuel Combustion

Non

- agricultural stationary diesel engines fall under the Other Fuel Combustion category. These equipment types include air

com pressors, prime and backup generators, prime and backup pumps, and other miscellaneous stationary diesel engines. Stationary non

- agricultural diesel engines are assumed to be engines that remain at a facility for at least 12 months.

The stationary non

- agr icultural diesel engine population was based on population estimates from ARB’s OFFROAD model database of

non

- road mobile diesel engines. The OFFROAD population estimates were developed from nationwide engine sales data provided by PSR in 1996 and the ARB Stationary Source Division (SSD) Portable Equipment Database.

Emission factors were obtained from Appendix A of the ARB’s OFFROAD Model Documentation. They are based on the U.S.
EPA’s adopted diesel standards and reflect California regulations.

The year 2 002 engine populations provided in this methodology were grown to the 2012 base year using the OFFROAD2007 model. The growth surrogates used in the OFFROAD model were obtained from a 1994 study by California State University

- Fullerton (CSUF) entitled “A Study to Develop Projected Activity for
Non

- Road Mobile Categories in California, 1970

- 2020”.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/FULLPDF/FULL1

- 2.pdf

Laundering

The Laundering category includes VOC emissions from perchloroethylene dry cleaning establishments.

Activity information is taken from national consumption rates for the year 2001 cited in the Solvents Update July/August 2002 report compiled by the Halogenated Solvents Industry Alliance.

The emission factors were obtained by applying a 25 percent

recove ry rate to perchloroethylene's density of 13.5 pounds per gallon. This recovery rate was based on data in the CAPCOA Air Toxic "Hot Spots" Program Perchloroethylene Dry CleanersSeptember 2016

13 Industry

- wide Risk Assessment Guidelines (June 20, 2000).

Emissions were grow n from the original 2001 estimates to 2012 using population data from the California Department of Finance (2013).

Additional information on this methodology is available at: http://www.arb .ca.gov/ei/areasrc/onehtm/one3

- 1.htm

Degreasing

These categories include VOC emissions resulting from the use of solvents in degreasing operations in the manufacturing and
maintenance industries. The emission estimates from this source category are based o n the E.H. Pechan and Associates, Inc. (Pechan) report titled, "Solvent Cleaning/Degreasing Source Category Emission Inventory." (1996)

To estimate degreasing emissions, Pechan collected activity data by surveying solvent users in two major groups: manufac turing and
maintenance. Emissions were estimated for 32 equipment and solvent pairs. For the manufacturer's survey, the emission factor for pure solvents is the density of the particular solvent. The emission factor for solvent blends is the density of t he solvent multiplied by the total organic gas (TOG) content of the solvent.
Exhaust controls were taken into account if used. For the maintenance survey, the emission factors are the density of the
solvent with no exhaust controls.

The 1993 emissions est imates were grown to 2012 based on manufacturing output data (SIC codes 20

- 39) developed by
Pechan

.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/area src/onehtm/one3

- 2.htm

Food and Agriculture

The Food and Agriculture category includes estimates of evaporative VOC emissions from processes in the agricultural and food processing industries. W ine fermentation and wine aging are among the largest contribu tors of these emissions

.
Wine fermentation volumes in California are reported by the U.S.
Alcohol and Tobacco Tax and Trade Bureau. ARB staff derived the emission factors from a computer model developed by Williams and
Boulton. The model simulates the effe cts of temperature and the sugar concentration on the amount of evaporative ethanol lossSeptember 2016

14 during isothermal batch fermentation. Emissions were initially
estimated for 200 2 and grown to later years using Beverages (Alcoholic & Non

- Alcoholic) economic output.

The wine aging category also includes evaporative ethanol emissions from the aging of wine in oak barrels to produce brandy. The 1990 grape production in each county is taken from the Annual Crop and Livestock Report (Annual Crop Report ) prepared by each County Agricultural Commissioner. The amount of grapes produced was determined from the California Department of Food and Agriculture (CDFA) along with the Annual Crop Report. The amount of grapes crushed in the grape growing districts is from the CDFA

re port, "Final Grape Crush Report, 1990 Crop."

An emission factor for brandy was derived by Hugh Cook of the Wine Institute. Emissions were initially estimated for 1992 then grown to subsequent base years using Dollar Output for Food Manufacturing (SIC 20).

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/arbindprofandag.htm

Petroleum Marketing

The Petroleum Marketing category includes activities associated with the distribution of petroleum base products, including fuel loading and unloading, gasoline dispensing facilities, and gasoline storage tanks.

Marine Petroleum Loading

These categories are used to inventory 1987 hydrocarbon
emissions assoc iated with loading crude oil, residual oil, gasoline, and jet fuel into marine tankers and gasoline into barges. Emissions result from the displacement of vapors existing in the tank before loading and those generated as new product is loaded.

The amounts of crude oil, gasoline, jet fuel, and residual oil shipped off from California ports was obtained from an United States Army Corps of Engineers report "Waterborne Commerce of the United States, Calendar Year 1986, Part
4”

The emission factor for crude oil loading into tankers was obtained from the report "Hydrocarbon Emissions During Marine Loading of Crude Oils" from Western Oil and Gas Association (1977). The gasoline emission factors forSeptember 2016

15 loading into tankers and barges and jet fuel into tankers
were obt ained from ARB’s "Report to the Legislature on Air Pollutant Emissions from Marine Vessels" (1984). The emission factor for residual oil loading into tankers was obtained from the "Inventory of Emissions from Marine Operations within California Coastal Wa ters, Preliminary Draft" report by Scott Environmental Technology, Inc. (1980).

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/arbpetprodma rkpm.htm

Marine Petroleum Unloading

These categories are used to estimate hydrocarbon emissions associated with lightering crude oil and ballasting marine vessels after unloading crude oil or gasoline.

The amounts of crude oil and gasoline unloaded at C alifornia ports were obtained from the United States Army Corps of Engineers report "Waterborne Commerce of the United States, Calendar Year 1986" Part 4.

Crude oil lightering data was obtained from the Bay Area Air Quality Management District (AQMD) for 1 987. Crude oil and gasoline ballasting data for San Luis Obispo for 1987 was obtained from the Army Corps of Engineers. The volume of water used for ballasting following a cargo discharge was obtained from ARB’s "Report to the Legislature on Air Pollutan t Emissions from Marine Vessels" (1984).

The crude oil lightering emission factor was obtained from "Hydrocarbon Emissions During Marine Loading of Crude Oils," Western Oil and Gas Association (1977).

Ballasting crude oil and gasoline vessels emission factors were obtained from "Inventory of Emissions from Marine Operations within the California Coastal waters," by Scott Environmental Technology, Inc. (1981)

Additional information on this methodology i s available at: http://www.arb.ca.gov/ei/areasrc/arbpetprodmarkpm.htm

Gasoline Dispensing Facilities

These categories include estimates of organic gas emissions resulting from the storag e and transfer operations atSeptember 2016

16 gasoline dispensing facilities. Gasoline dispensing facilities consist of gasoline retail outlets and private dispensing facilities. Emissions from these operations include the working losses and breathing losses from undergr ound tanks, vapors displaced through vehicle refueling, and spillage.

The total gasoline sales for service stations in the California by county were taken from the 1997 Annual Report from the California State Board of Equalization. County level
emissions were estimated using taxable sales, population, vehicle miles of travel, and the number of registered vehicles by county from the California Department of Transportation

. Emissions were grown to 2012 based on fuel consumption
estimates from EMFAC.

Emissio n factors are based on the CAPCOA Air Toxics "Hot Spots" Program Gasoline Service Station Industrywide Risk
Assessment Guidelines Document.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/arbpetprodmarkpm.htm

Bulk Gasoline Storage

This Bulk Gasoline Storage category estimates VOC emissions from gasoline cargo tanks. Pressure

- related fugitiv e emissions occur during gasoline storage by leaking from fittings, valves and other connecting points in the vapor collection system on a cargo tank. Emissions are developed by both ARB and local air districts. The following sections
describe ARB’s metho dology.

The total highway gasoline sales cited in the Caltrans report, "Travel and Related Factors in California" (1997) represents all gasoline transported by gasoline cargo tankers in
California. The emission factors are derived from the data in the rep ort, "Emissions from Gasoline Cargo Tanks, First Edition," published by the Air and Waste Management
Association in 2002.

The initial emission estimates for 1997 were grown to 2012 using a growth parameter developed by Pechan based on gasoline and oil ex penditures data.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/arbpetprodmarkpm.htmSeptember 2016

17 Oil and Gas Production

Oil and Gas Production categorie s are related to fugitive emissions from sumps, pits, valves, fittings, pumps, wells and storage tanks during oil and gas exploration and extraction. The following describes each of the categories in detail.

Fugitive Losses

- Sumps and Pits

These categorie s include VOC emissions associated with the operation of sumps and pits used in oil production processes. A sump is defined as an excavated lined or unlined pit in the ground that is used to separate oil, water, and sand for oil and gas production operatio ns.

The amounts of sump emissions were estimated by ARB from the districts that reported sump usage in their jurisdiction in 1991. The data gathered were sump surface area, the type of sump, and the API gravity of the sump liquid.

TOG emission factors for light crude sumps were based on test data collected by Rockwell in a report prepared for the American Petroleum Institute entitled "Fugitive Hydrocarbon Emissions from Petroleum Production Operations," 1980. The VOC emission factors for heavy crude were o btained
from ARB tests conducted between 1983 and 1986. From the Rockwell TOG emission factors, ARB derived corresponding emission factors for VOC by using speciation profiles provided by Rockwell.

Emissions were grown to the 2012 base year using is dollar output for oil and gas extraction (SIC 13).

The San Joaquin Valley Air Pollution Control District (APCD) supplied an updated methodology for the Sump and Pits category in 2007. The number and surface area of active sumps and well cellars was determined f rom an industry survey of oil production facilities within the District. Emission
factors are taken from ARB’s Technical Guidance Document for the Emission Inventory Criteria and Guidelines Regulation for AB 2588. Emissions in the San Joaquin Valley were grown from 2007 to 2012 using annual oil production data from DOGGR.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/onehtm/one4

- 1.htmSeptember 2016

18 Fugitive losses

- Valves and Fittings

These categories include the fugitive emissions from valves and fittings (threaded and flanged connections) associated with oil production operations.

The activity data are based on 1987 lease data from the California Departm ent of Conservation Division of Oil, Gas and Geothermal Resources (DOGGR). These data were
used to determine the number of wells on each lease and the gas to oil ratios for these wells.

The emission factors were derived from two sources.
General oil and gas production emission factors were obtained from Rockwell International's report "Fugitive Hydrocarbon Emissions from Petroleum Production Operations" (March 1980). KVB Incorporated, in its report
"Emission Characteristics of Crude Oil Production Operat ions in California" (January 1983), based its composite emission factors for valves and fittings on a 1979

- 80 field study of California oil production operations.

Emissions from 1987 were grown to 2012 using dollar output for oil and gas extraction (SIC 13) and annual oil production in the San Joaquin Valley.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/onehtm/one4

- 2.htm

Fugitive losses

- Pum

ps, Compressors and Well Heads

These categories include the fugitive VOC emissions from pumps, compressors, and well heads associated with active wells. The activity data for these sources are from the California Division of Oil and Gas and represent 1987 . The emission factors are from a report by KVB, Inc., "Emission Characteristics of Crude Oil Production Operations in California" (January 1983). Emissions were grown to the 2012 base year using dollar output for oil and gas extraction (SIC 13) or annual oil production in the San Joaquin Valley.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/onehtm/one4

- 3.htm

Tertiary Oil Production

- Steam Driv e and Cyclic Wells

These categories include the VOC emissions associated with steam drive wells and cyclic wells. In oil productionSeptember 2016

19 fields, steam is injected in two ways: continuously through an injection well (steam drive) and periodically into the oil

p roduction well itself (cyclic injection). These sources of emissions are only found in Kern County in the San Joaquin Valley Air Basin.

The activity data is based on the total number of steam drive and cyclic wells. Both steam drive and cyclic wells were surveyed by the ARB in 1985.

The emission factors are obtained from an ARB report, "A Suggested Control Measure for Emissions of Photochemically Reactive Organic Compounds from Vents of Steam Drive Oil Production Wells" (January 1982), and a report by KVB , Inc., "Emission Characteristics of Crude Oil Production Operations in California" (January 1983).

Emission estimates for 1985 were grown to 2012 using annual oil production.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/onehtm/one4

- 5.htm

Tertiary Oil Production

– Pseudo Cyclic Wells

This methodology estimates VOC emissions from pseudo cyclic wells. The activity is based on th e number of steam drive wells and injection wells. The emission factor for steam drive wells is obtained from a report by KVB, Inc.,
"Emission Characteristics of Crude Oil Production Operations in California" (January 1983). An injection well
has an emiss ion factor of zero.

Emissions from 1987 were grown to 2012 using dollar output for oil and gas extraction (SIC 13) or annual oil production in the San Joaquin Valley.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/onehtm/one4

- 4.htm

Gas Stripping

These categories include the VOC emissions associated with natural gas processing. Natural gas obtained from gas wells contains impurities such as water , carbon dioxide, and sulfur compounds. Natural gas must be processed to remove these impurities. The sources of fugitive emissions during gas stripping originate from leaks in compressorSeptember 2016

20 seals, pump seals, valves, and fittings.

The activity data for the a mounts of natural gas produced in each county in California were obtained from a report by the California Division of Oil and Gas, "73rd Annual Report of the State Oil and Gas Supervisor, 1987."

The emission factor for natural gas stripping was taken from a report by the U.S.EPA "Revision of Evaporative Hydrocarbon Emission Factors" (1976).

Emissions from 1987 were grown to 2012 using dollar output for oil and gas extraction (SIC 13) or annual oil production in the San Joaquin Valley.

Additional informatio n on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/onehtm/one4

- 6.htm

Oil Production Tanks

This category includes the VOC emissions from both open top and fixed roof tan ks associated with oil production operations. The two major sources of tank emissions are breathing losses and working losses.

The activity data are obtained from the Oil Production Tank Survey conducted in 1984. This survey was developed by representativ es from the oil production industry, air pollution control districts, and ARB. Data obtained from this survey includes tank throughputs.

The emission factors to calculate breathing and working loss
emissions are from the U.S.EPA's AP

- 42, Section 4.3 (4th

e dition). Control factors added to each equation to account for any California

- specific control measures that are installed
on the tanks.

Emissions from 1987 were grown to 2012 using dollar output for oil and gas extraction (SIC 13) or barrels of oil in th e San Joaquin Valley.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/onehtm/one4

- 7.htmSeptember 2016

21 Area

- W ide Source Emissions

Managed Burning and Disposal

The Managed Burning and Disposal includes emissions from agricultural and forest management burns, also known as prescribed burns. A prescribed burn is a fire ignited by a planned management action, most often administered by a public land management agen cy.

Agricultural burn activity is updated annually with emissions data reported by the local air districts. The 2012 base year inventory

uses burn activity reported for the year 2012. Emissions are calculated using crop specific emission factors and fuel loadings. Monthly burn activity provides seasonal emission estimates.

Prescribed burn emissions are calculated using the Emission Estimation System (EES) developed by UC Berkeley's Center for

t he Assessment and Monitoring of Forest and Environmental Resources (CAMFER). The EES implements the First Order Fire Effects Model (FOFEM 6.0) developed by the U.S. Forest Service (USFS) Fire Sciences Laboratory. Known fire perimeters are
overlaid on the USFS Fuel Characterization Classification System land cover vegetation layer establishing the acres of specific vegetation burned in each fire. Fuel loading characteristics and moisture factors are assigned to each vegetation type using the
USFS Wildland Fire Assessment System. The EES then calculates the tons of fuel consumed in each vegetation type and applies the appropriate emission factor to estimate emissions per burn event.

Emission factors are contained in the FOFEM documentation. The
emission factors are characterized by ten different fuel components that comprise a vegetation type, including duff, litter, wood of varying diameters, herbaceous vegetation, understory vegetation, branch and canopy fuels.

Statewide interagency prescribed wild l and burn data w ere retrieved from the California Department of Forestry and Fire Protection (CDF), Fire and Resources Assessment Program (FRAP) fire perimeters geodatabase.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/see/see.htm

.

Pesticides

This category includes estimates of VOC emissions resulting from the application of agricultural and structural pesticides. EmissionsSeptember 2016

22 were calculated by applying Emission Pote ntial (EP) values to the amount of reported pesticide application in the Pesticides Use Report ( PUR ) dataset. Each pesticide has a specific EP value assigned.

The California Department of Pesticide Regulation (DPR) requires reporting of all agricultural an d structural pesticide applications

. DPR develops month

- specific emission estimates from this reported information. Each calendar year, DPR updates the inventory based on the PUR that provides updated information from 1990 to the most current data year av ailable. This includes estimates for the 2012 calendar year.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/fullpdf/full6

- 4.pdf

Consumer Products

The Consumer Products category was updated to reflect the three

most r e cent Consumer Products Surveys conducted by ARB for the years 2003, 2006, and 2008. Together these surveys collected updated product and ingredient information for approximate ly 350 consumer product categories. ARB staff determined the total sales and total VOC emissions for the various product categories based on the survey data. In 2011 the Consumer Products inventory categorization was expanded to provide more detail , and in 2014 the 2010 inventory was updated for 11 product categories.

Emissions are grown to the 2012 base year using population data from the California Department of Finance (2013)

Additional information on this methodology is available at: http://www.arb.ca.gov/consprod/survey/survey.htm

Cooking

Commercial Cooking emission estimates are based on methodologies developed by the local air districts. The 2012 base year inventory includes an upd ate for the San Joaquin Valley based on 2008 activity data that includes the number of restaurants, the number and type of cooking equipment, the food type, and
emission factors from US EPA’s 2002 NEI. Emissions for this category were grown to 2012 based on population projections provided by the California Department of Finance (2013).

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/are asrc/distmiscproccook.htmSeptember 2016

23 Architectural Coatings

Architectural coatings are surface coatings applied to stationary
structures and their accessories such as mobile homes, pavements , or curbs as protection from environmental conditions.
VOC emissions result from the application of these oil

- based and

water

- based coatings and the associated use of thinning and cleanup solvents and additives.

Annual average VOC emission estimates for the year 2004 were derived from data obtained through a survey of manufactu rers of architectural and industrial maintenance coatings conducted by ARB’s Stationary Source Division in 2005. The results of the survey provided the number of gallons of coatings sold in California in 2004 as well as the percentage that was oil versus water

- based.

Emission factors were developed through the ARB sponsored a
research project “Improvement of Emissions Inventories for Industrial Coatings and Thinning and Cleanup Solvents” in 2004.

Chemical composition data obtained from the survey report we re used to inform the fractions of VOCs for water

- based and oil

- based coatings as well as for thinning and cleanup solvents and additives.
The emission estimates include benefits of the 2003 and 2007 ARB Suggested Control Measure for Architectural Coating s.

Growth to the 2012 base year was based on DOF estimates of occupied housing units (December 2013).

Additional information on this methodology is available at: http://www.arb.ca.gov/coatings/arch/survey/2005/2005survey.htm

Residential Fuel Combustion

The Residential Fuel Combustion category includes emission
estimates for wood combustion from fireplaces and wood stoves and natural gas combustion for space heating, water heating, and cooking. The following sections describe the categories in more
detail.

Residential Wood Combustion

This category represents emission estimates from wood

burning fireplaces and wood stoves including fireplace inserts and pellet stoves

ARB staff updated the Residential Wood Combustion methodology in 201 1 to reflect recent survey data on typesSeptember 2016

24 of wood burning devices and wood consumption rates, updates to the 2002 U.S. EPA Nat ional Emission Inventory (NEI) emission factors, and improved calculation approaches. The update reflects wood combustion surveys conducted by several districts including Bay Area AQMD in 2007, South Coast AQMD in 2003 and 2006, Placer County
APCD in 2007 , San Joaquin Valley APCD in 2008, and Sacramento Metropolitan AQMD in 2007. This update also accounts for lower emissions resulting from various district curtailment programs

Emissions from fireplaces were initially estimated in 2005 then grown to subseq uent base years using Housing Unit data from the California Department of Finance, fireplace data from the U.S. Census Bureau “American Housing Surveys”, and Regional Economic Models Inc. (REMI) population data. Emissions from wood stoves were initially

e stimated in 2005 then grown to subsequent base years using Housing unit data from California Department of Finance and Department of Energy 1998 Annual Energy Outlook (AEO) Renewables data.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/arbmiscprocresfuelcom.htm

Residential Natural Gas Combustion

Combustion of natural gas in the residential sector is broken down into four categories: sp ace heating, water heating, cooking, and unspecified. The unspecified category includes the combustion of natural gas in appliances such as clothes dryers, barbecues, and water heaters used for pools, spas
and hot tubs.

The amount of natural gas consumed in the residential sector for each county was obtained from the California Energy Commission report, "Quarterly Fuel and Energy Report, 1997 Residential Natural Gas Consumption." The amount of natural gas was apportioned into the four categories described above based on percentages from the California Energy Commission report, "Breakdown of California Natural Gas Usage by Appliance and by Utility Company for All Housing Types Combined." The emission factors for residential natural gas combustion were obtain ed
from EPA's AP

- 42 5 th Edition (1995)

.

Emissions were initially calculated for 1998 then grown toSeptember 2016

25 subsequent base years. The growth parameters were developed by Pechan and Associates (Pechan) as documented in their report, " Development of Emission Growth Surrogates and Activity Projections Used in Forecasting Point and Area Source Emissions, Final Report ," February 26, 2001. For cooking and unspecified,
data on housing units were adjusted by Pechan using the Department of Energy's Annual Energy Outlook residential natural gas consumption projections.

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/ONEHTM/ONE7

- 2.HTM

Residential Distillate Oil and Liquefied Petroleum Gas

The residential distillate oil/liquefied petroleum gas (LPG) category includes emissions occurring in the residential
sector. Distilla te oil for heating is used only in older homes and remote areas where natural gas lines are not available.

Activity is based on the number of housing units, population, and LPG and distillate oil capacities. The 1991 Fuels Report Working Paper published b y the California Energy Commission was used to determine energy demand by fuel type in terms of the number of houses heated by a specific fuel in a particular area. Heating degree days (HDD) are used to estimate how many heating days are likely to occur
in a particular area.

This category uses emission factors from U.S. EPA's AP

- 42. The emissions were initially calculated in 1993 then grown to subsequent base years using Housing Unit data from the California Department of Finance ( 2013)

Additional informat ion on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/ONEHTM/ONE7

- 3.HTM

Asphalt Paving

Asphalt paving estimates are based on various methodologies us ed by the local air districts. As an example of a typical methodology, the San Joaquin Valley APCD used emi ssion factors taken from two studies: KVB’s “Control of Hydrocarbon Emissions from Stationary Sources in the California South Coast Air Basin” (1978)
and “Central Calif ornia Ozone Study, Attachment C: Asphalt Paving and Roofing.” by Sonoma Technology, Inc. (2003)

Emissions for this category are grown to the 2012 base year usingSeptember 2016

26 construction employment from the REMI model.

Additional information on the San Joaquin Valley APCD methodology is available at: http://www.valleyair.org/Air_Quality_Plans/EmissionsMethods/Meth odForms/Current/AsphaltPaving200 8.pdf

Coatings and Related Process Solvents

The Coatings and Related Process Solvents category includes
VOC emissions from auto refinishing , surface coatings, and thinning and cleaning solvents.

Auto Refinishing

VOC emissions from auto refinishing operat ions are related to solvents contained in products such as auto refinishing paints, enamels and lacquers, refinish primers and undercoatings. Emissions are developed by both ARB and local air districts. The following sections describe ARB’s methodology.

Emissions from automotive coatings are estimated from the Automotive Coatings Survey conducted by the ARB Stationary Source Division (SSD) in 2002. A total of 17 companies provided data. The survey collected data on the VOC ingredients of products, which were then used to estimate emissions from these specific automotive coatings.

The survey also collected information on speciation of VOCs. The 2001 emission estimates were grown to 2012 using Pec h an’s auto refinishing growth parameter from 2002
based on jobs in the automobile services industry. For Southern California, growth was based on employment in automobile services including car rental and miscellaneous repair. (SIC 75 and 76).

Additional information on this methodology is available at: http://www.arb.ca.gov/coatings/autorefin/scm/sreport/scmsta ffreport.htm

Surface Coatings

The Surface Coatings categories estimate VOC emissions from the application of surface coatings in the manufacturing and industrial sectors. These include coatings for marine, paper, fabric, metal, and industrial products

. Emissions are developed by both ARB and local air districts. The followingSeptember 2016

27 sections describe ARB’s methodolog ies.

For marine coatings, the activity data were obtained from national production data from the Bureau of the Census 1984 report entitled "1982 Census of Manufacturers, Paint and Allied Products". For paper and fabric coatings,
estimated use in Californ ia is based on SSD's 1977 survey data and an annual growth factor of 1.68 taken from ARB’s "Consideration of Proposed Rule for Control of VOCs from Paper and Fabric Coating Operations" (1978). The emission factors were obtained from developed composites f or each category from data in the 1977 survey.

Emissions were initially estimated for 1983, then grown to subsequent base years using employment in the manufacturing of transportation equipment (SIC 37), dollar output from manufacturing of paper and allied products (SIC 26), manufacturing of textiles (SIC 22), manufacturing of furniture (SIC 25), and the total manufacturing industry (SICs

20

- 39)

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/arbcleancoatreproc.htm

Thinning and Cleaning Solvents

This category includes the VOC emissions from thinning solvents used with industrial surface coatings. This solvent category includes the use of thin ners used for dopes, lacquers, and oleoresinous thinners. Emissions are developed by both ARB and local air districts. The following section describes ARB’s methodology.

The Thinning and Cleaning Solvents category was updated using data from the Census Bureau’s report “Current Industrial Reports, Paint & Allied Products” (2002). U.S. consumption of each coating type within each category was apportioned to California using employment data specific to the coating type.

Emission estimates are grown to t he 2012 base year using the manufacturing output parameter developed by Pechan.

Additional information on this methodology is avai l able at: http://www.arb.ca.gov/ei/areasrc/arbcleancoa treproc.htmSeptember 2016

28 Adhesives and Sealants

This category includes VOC emissions from solvents
contained in adhesives and sealants used for the construction, transportation and other industries. The emissions are broken down into two subcategories: solvent

based an d water

- based.

The activity data for adhesives and sealants used nationally in 1983 for construction, transportation and other industries were obtained from the report "Outlook for the U.S. Adhesives and Sealants Industry," by Decision Resources.
Californi a's percent use of the national production was based on a ratio of California to national use, from the Science Applications International Corporation (SAIC) report titled "Development and Improvement of Organic Compound Emissions Inventory for California, " published in 1985.

The emission factors for solvent

- based adhesive and sealants for the transportation and other industries categories were based on data from the SAIC report. The
emission factor for solvent

- based adhesive and sealants for
the constructi on industry was based on data from an U.S. EPA report titled "Preliminary Draft of Industry Classification, Estimates of Adhesives Consumed, and Solvent Emissions."
The emission factor for all water

- based adhesives and
sealants was based on data from Decis ion Resources.

The emissions from 1983 were grown to 2012 using dollar output for manufacturing industries (SICs 20

- 39).

Additional information on this methodology is available at: http: //www.arb.ca.gov/ei/areasrc/arbcleanadhseal.htm

Farming Operations

This category provides estimates of the VOC emissions produced by dairy cattle, range cattle, poultry, swine, sheep, goats, and horses. Emissions are calculated by multiplying a per animal emission factor by the population of each animal type.

The dairy, feedlot, and range cattle emission estimates reflect
livestock population data from the U.S. Department of Agriculture’s (USDA) 2012 Census of Agriculture ( 2007 ) . The emission
estimates for other livestock categories are based on the USDA 2007 Census of Agriculture.September 2016

29 Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/arbmiscp rocresfarmop.htm

Fires

This category is used to estimate the combustion emissions from structure, mobile home, and automobile fires. The Structure Fires category includes both residential and commercial structures.

Estimates of building, mobile home, and automobile fires are based on data from a 1996 report by the California Fire Incident Reporting System (CFIRS), California State Fire Marshall's Office.

Structure fire emission factors were obtained from the report, "Fires Dynamics of Model Wood Buildings," Fire and Flammability, Vol. 3, p. 336 (October 1972). The emission factor for NOx is assumed to be similar to the factor for municipal refuse listed in AP

- 42, Sections 2.2 and 2.4. This amount, representing both structural loss and content loss, was calculated using data from the California State Fire Marshall Office, the Census Bureau, the National Association of Home Builders, and the National Bureau of Standards.

For automobile fires, composite emission factors have been calculated as a weighted average of the emission factors listed in

AP

- 42 Table 2.2

- 1 (uncontrolled auto body incineration) and Table

2.4

- 1 (open burning of automobile components incl uding upholstery, belts, hoses, and tires burned in common).

Emissions were initially calculated for 1999, and then grown to subsequent base years using the following growth factors. For structure fires, the growth parameters were developed by Pechan
and are based on occupied housing units. For automobile fires, the growth parameters are based on population from the Department of Finance (2013).

Additional information on this methodology is available at: http://www.arb.ca.gov/ei/areasrc/ONEHTM/ONE7

- 14.HTM