From: Armen Kamian

To: LEVIN, NANCY

Subject: FW: PM 2.5 Emissions Inventory

Date: Monday, December 16, 2013 1:09:01 PM

Hi Nancy,

See the message from Gabe at ARB:

Armen

From: Ruiz, Gabe@ARB [mailto:gruiz@arb.ca.gov] 

Sent: Monday, December 16, 2013 12:49 PM

To: Armen Kamian

Subject: RE: PM 2.5 Emissions Inventory

We updated the categories listed below (any category not listed --e.g., agricultural equipment--

would have come from OFFROAD 2007):

Cargo Handling Equipment (CHE)

The emissions inventory for the Cargo Handling Equipment (CHE) category was updated to reflect

new information on equipment population, activity, recessionary impacts on growth, and engine

load. The new information includes regulatory reporting data which provide an accounting of all the

cargo handling equipment in the state including their model year, horsepower and activity.

Commercial Harbor Craft

In 2007 ARB adopted a Commercial Harbor Craft Regulation to reduce emissions from diesel engines

on commercial harbor craft operated within California waters. The emissions inventory reflects

amendments adopted in 2010, along with updates to the equipment population, annual activity,

and regional allocation.

In-Use Off-Road Equipment

ARB developed this model in 2010 to support the analysis for amendments to the In-Use Off-Road

Diesel Fueled Fleets Regulation. Staff updated the underlying activity forecast by evaluating

available economic forecast data. Using the same methodologies as developed for the Rule

inventory in 2010, staff evaluated current construction employment forecasts developed by UOP

and UCLA. Results indicated that in 2019 that construction employment would be roughly 10%

lower than previously anticipated due to lackluster economic growth since the recession ended. This

10% reduction in employment is assumed to also apply to construction equipment activity.

Locomotives

The locomotive inventories reflect the 2008 U.S.EPA locomotive regulations and adjustments due to

economic activity.

Ocean-Going Vessels (OGV)

The OGV inventory includes vessel-specific data, improved vessel traffic network, vessel-specific

hoteling and anchorage times, and improved vessel speeds. Staff has refined the inventory to
support rulemakings on the sulfur content in fuel. In general, the updates include improved

algorithms for vessel speed reduction (VSR), auxiliary engine power, and estimating low load

adjustment factors. Recession impacts are based on container throughput statistics for the Ports of

Los Angeles, Long Beach and Oakland. Using this statistic, estimated OGV activity was down about

25% for the combined ports of Los Angeles and Long Beach and about 15% for the Port of Oakland

between 2006 and 2009.

Pleasure craft and Recreational Vehicles

A new model was developed in 2011 to estimate emissions from pleasure craft and recreational

vehicles. In both cases, population, activity, and emission factors were re-assessed using new

surveys, registration information, and emissions testing.

Transportation Refrigeration Units (TRU)

The TRU model was developed to support analysis for the 2011 amendments to the Airborne Toxic

Control Measure for In-Use Diesel-Fueled Transport Refrigeration Units (TRU) and TRU Generator

Sets and Facilities Where TRUs Operate. The inventory reflects the requirements of the rule along

with updates to activity, population, growth and turn-over data, and emission factors.

Full documentation for the methodology updates is posted on our off-road emissions inventory web

page at http://www.arb.ca.gov/msei/categories.htm#offroad_motor_vehicles.

Please do not hesitate to contact me again if there are any further questions.

--Gabe