STAFF REPORT: INITIAL STATEMENT OF REASONS 

NOTICE OF PUBLIC HEARING TO CONSIDER REQUIREMENTS TO REDUCE 

IDLING EMISSIONS FROM NEW AND IN-USE TRUCKS, BEGINNING IN 2008 

Date of Release: September 1, 2005 

Scheduled for Consideration: October 20-21, 2005 

This report has been prepared by the staff of the California Air Resources Board. 

Publication does not signify that the contents necessarily reflect the views and policies 

of the Air Resources Board, nor does mention of trade names or commercial products 

constitute endorsement or recommendation for use. 
 i

TABLE OF CONTENTS 

LIST OF TABLES .......................................................................................................... iii

LIST OF FIGURES......................................................................................................... iv

EXECUTIVE SUMMARY ................................................................................................ v

I. INTRODUCTION ...................................................................................................... 1

II. BACKGROUND ....................................................................................................... 3

III. NEED FOR CONTROL ............................................................................................ 7

IV. SUMMARY OF PROPOSED REQUIREMENTS...................................................... 8

V. TECHNOLOGICAL FEASIBILITY ......................................................................... 27

VI. REGULATORY ALTERNATIVES.......................................................................... 33

VII. ECONOMIC IMPACTS........................................................................................... 36

VIII.ENVIRONMENTAL JUSTICE ................................................................................ 42

IX. ENVIRONMENTAL IMPACTS AND COST-EFFECTIVENESS............................. 43

X. CONCLUSIONS AND RECOMMENDATION ........................................................ 53

XI. REFERENCES....................................................................................................... 54

APPENDIX A 

PROPOSED AMENDMENTS TO TITLE 13, CALIFORNIA CODE OF REGULATIONS, 

SECTION 1956.8, EXHAUST EMISSION STANDARDS AND TEST PROCEDURES 

FOR 1985 AND SUBSEQUENT MODEL YEAR HEAVY-DUTY ENGINES AND 

VEHICLES........................................................................... A-1 

PROPOSED AMENDMENTS TO TITLE 13, CALIFORNIA CODE OF REGULATIONS, 

SECTION 2404, EMISSION CONTROL LABELS AND CONSUMER INFORMATION – 

1995 AND LATER SMALL OFF-ROAD ENGINES .............................................A-1 

PROPOSED AMENDMENTS TO TITLE 13, CALIFORNIA CODE OF REGULATIONS, 

SECTION 2424, EMISSION CONTROL LABELS – 1996 AND LATER OFF-ROAD 

COMPRESSION-IGNITION ENGINES............................................. A-1 
 ii

PROPOSED AMENDMENTS TO TITLE 13, CALIFORNIA CODE OF REGULATIONS, 

SECTION 2425, DEFECTS WARRANTY REQUIREMENTS FOR 1996 AND LATER 

OFF-ROAD COMPRESSION-IGNITION ENGINES .............................................A-1 

PROPOSED AMENDMENTS TO TITLE 13, CALIFORNIA CODE OF REGULATIONS, 

SECTION 2485, AIRBORNE TOXIC CONTROL MEASURE TO LIMIT DIESELFUELED COMMERCIAL MOTOR VEHICLE IDLING .................................... A-1 

APPENDIX B – PROPOSED AMENDMENTS TO THE CALIFORNIA EXHAUST 

EMISSION STANDARDS AND TEST PROCEDURES FOR 2004 AND SUBSEQUENT 

MODEL HEAVY-DUTY DIESEL-ENGINES AND VEHICLES............................... B-1 
 iii

LIST OF TABLES 

Table 1: Certification Test Cycle ................................................................................... 12

Table 2: Net Fuel and Maintenance Savings................................................................. 40

Table 3: Fleet Average Idle Emission Factors............................................................... 44

Table 4: Off-Road Diesel Emission Standards (g/kW-hr) .............................................. 45

Table 5: Diesel Fueled APS Emission Rates ................................................................ 46

Table 6: 2010 Estimated Statewide Idling Emission Benefits........................................ 48

Table 7: 2020 Estimated Statewide Idling Emission Benefits........................................ 48

Table 8: 2010 Estimated South Coast Air Basin Idling Emission Benefits..................... 49

Table 9: 2020 Estimated South Coast Air Basin Idling Emission Benefits..................... 49

Table 10: Cost-Effectiveness in Dollars per Pound of NOx+ROG Reduced ................. 51
 iv

LIST OF FIGURES 

Figure 1. Impacts on Operators – 2008 and Newer California Truck ........................20 

Figure 2. Impacts on Operators – 2007 and Newer Out-of-State Trucks and 

2007 California Trucks .............................................................................. 21 

Figure 3. Impacts on Operators – Pre-2007 Out-of-State and California Registered 

Trucks .................................................................................................... 22 

Figure 4. Label for an engine meeting the optional NOx standard ................................ 26

Figure 5. Label for an APS with additional PM control .................................................. 26

Figure 6. Hologram........................................................................................................ 26

Figure 7. California GHG emissions by Type of Gas in 2003 (Bemis, 2005)................ 47

Figure 8. Sources of California’s 2003 GHG Emissions (by End-Use Sector) 

(Bemis, 2005).......................................................................................................... 47
 v

EXECUTIVE SUMMARY 

California’s plan for reducing reactive organic gases (ROG) and oxides of nitrogen 

(NOx), which contribute to both ozone and particulate matter (PM) formation, is set forth 

in the 2003 State and Federal Strategy for the California State Implementation Plan

(2003 SIP). Diesel engines produce a significant portion of the state’s air pollution and 

toxic emissions. Controlling these emissions is therefore an important element of 

California’s strategy for attaining air quality standards and constitutes a significant part 

of the 2003 SIP. Staff’s proposal reduces emissions resulting from the idle operation of 

diesel trucks, and is part of the 2003 SIP’s proposed on-road heavy-duty vehicle control 

measure “ON-ROAD HEAVY DUTY 3”. Staff’s proposal will contribute to fulfillment of 

the committed emission reductions from this control measure. 

Impacts of Idling 

In California, emissions generated by idling trucks pose a significant air quality problem. 

Truck operators generally idle their engines at truck stops and rest areas during layover 

hours to provide heat or cooling to the sleeper berth, to operate on-board electrical 

accessories, to maintain battery charge, and to warm the engine for easy start-up during 

cold weather. Truck idling is also significant at warehouse/distribution centers and port 

terminals where loading and unloading freight require long waiting periods. The high 

density of idling trucks at such locations for extended periods of time can produce highly 

localized and concentrated emissions, which adversely affect the health of the drivers 

and the neighboring communities. The health concerns become more serious when 

these idling centers are located in low income communities that are already 

disproportionately impacted by air pollution. Truck idling also consumes fuel, produces 

greenhouse gas emissions, and increases engine maintenance costs. 

Existing Regulations 

The Air Resources Board (ARB) on December 12, 2002 adopted requirements that 

operators of school buses, transit buses, and other commercial vehicles manually shut 

off their engines upon arriving at a school. Restarting the engines is limited to no more 

than 30 seconds before departing. The ARB subsequently adopted at its public hearing 

of July 22, 2004 more general requirements to limit emissions from idling trucks and 

buses. Operators of commercial trucks and buses are required to manually shut off 

their engines before the idling time limit of five minutes is reached. However, this 

requirement does not apply to idling sleeper berth equipped trucks unless they are 

located within 100 feet from residential homes or schools. 

Proposed Regulation 

Staff’s proposal would limit the amount of time sleeper berth equipped trucks are 

operated at idle and provide other options to accommodate driver comfort during times 

when the truck is not being driven. The proposal will also reduce fuel consumption and 

engine maintenance costs, thereby benefiting owners of compliant trucks. The proposal 

consists of two major components, affecting new engines and trucks, and existing 

engines and trucks. 
 vi

Proposed Requirements for New Trucks 

The new engine requirements apply to 2008 and subsequent model year diesel engines 

in trucks with a gross vehicle weight rating greater than 14,000 pounds. The proposal 

requires that they be equipped with a non-programmable engine shutdown system that 

automatically shuts down the engine after five minutes of continuous idling. The system 

would activate when the truck is stopped, the transmission is set in the “neutral” or 

“park” position, and the parking brake is engaged. If the parking brake is not engaged, 

the shutdown system would automatically shut down the engine after 15 minutes of 

continuous idling. This avoids undesirable or frequent engine shutdowns, such as when 

a truck is stopped in traffic congestion. In addition, the proposal allows the driver to 

reset the engine shutdown system timer as long as he or she is present inside the truck. 

It also includes override provisions when the engine is operating power take-off 

equipment. 

Trucks with an engine that utilizes the idle shutdown system would need to provide 

other methods for heating/cooling the cabin and powering accessories when the truck is 

not being driven. To meet those needs the truck manufacturer may install an auxiliary 

power system (APS), fuel-fired heater, thermal energy storage system, and/or a power 

inverter/charger with an electrically driven heating and air conditioning system. These 

systems are currently commercially available. 

If cab comfort devices such as those listed above are not offered by the engine or truck 

manufacturer, the owner may choose to equip his/her truck with aftermarket cab comfort 

devices. Other alternatives include parking at a truck stop that offers an off-board air 

conditioning or heating system, such as offered by IdleAire Technologies. 

To avoid incorporating a new engine shutdown system, an engine manufacturer may 

certify an engine to a NOx idling emission standard of 30 grams per hour. This option is 

proposed because it may be possible to control NOx emissions during idling. However, 

this option isn’t likely to become available prior to 2010 because that is when more 

advanced NOx controls are expected to be used for all heavy-duty engines. 

If manufacturers succeed in developing engines which meet the NOx idling emission 

standard, operators would be allowed to idle the main engine continuously to provide 

cab comfort and electrical power during rest periods, and would not need to install 

alternative cab comfort devices. However, they would still be subject to the existing five 

minute idling restriction when the truck is located within 100 feet of a restricted area. 

The proposed new engine requirements do not apply to gasoline engines or engines 

produced for use in buses (commercial buses as well as school buses), and 

recreational vehicles. 
 vii

Proposed Requirements for Existing Trucks 

Starting on January 1, 2008, operators of sleeper berth equipped trucks would be 

required to shut down their engines before a five-minute idle time limit is reached. This 

would apply to trucks registered in California and out-of-state. 

Owners of pre-2008 model year sleeper berth equipped trucks where drivers rest for 

extended periods in California, may need to retrofit their trucks to provide cab comfort 

during these rest periods. These cab comfort devices include, but are not limited to, 

APSs, fuel-fired heaters, thermal energy storage systems, and power inverter/chargers 

with electrically driven heating and air conditioning systems. Owners may also choose 

to park at a truck stop and plug in to on-shore electrical power to run an on-board 

electrically driven climate control system and accessories or use an off-board air 

conditioning or heating system, such as offered by IdleAire Technologies. 

Owners of 2008 and subsequent model year sleeper berth equipped trucks may also 

need to retrofit their trucks to provide cab comfort for rest periods if cab comfort devices 

are not offered by the engine or truck manufacturer at the time the truck is initially 

offered for sale. 

Proposed Emission Performance Requirements for Cab Comfort Devices 

Some of the cab comfort devices, such as internal combustion APSs and fuel-fired 

heaters, produce emissions. Performance requirements are proposed for these 

systems which differ depending on whether the truck’s engine is a 2007 or later model. 

All APS engines will have to be certified to the off-road emission standards. Currently 

available APSs are already doing this. Beginning in 2008, trucks with 2007 and 

subsequent model year engines equipped with a PM filter, or “trap”, will have the 

additional requirement to either route the APS’s exhaust through the PM trap of the 

main truck engine or to retrofit the APS separately with a “level 3” PM reducing device 

(likely to be a PM trap) which achieves an 85% reduction in emissions. Because of 

warranty issues, staff believes connecting main engine and APS exhaust systems 

together to control PM emissions will occur at the engine or truck manufacturer level 

rather than by aftermarket APS manufacturers. 

Trucks equipped with 2006 or older model year engines do not have PM aftertreatment 

systems and so owners may use a diesel-fueled APS without adding PM control 

devices. 

Beginning in 2008, all 2007 and subsequent model year trucks equipped with fuel-fired 

heaters will need to comply with the fuel-fired heater emissions requirements specified 

in the Low Emission Vehicle Program to operate in California. Several manufacturers 

currently produce fuel-fired heaters for heavy-duty trucks that meet the proposed 

requirement. 

The following flow chart summarizes in general staff’s proposed requirements and their 

impacts on truck operators. 
 viii

Certified to 

the low NOx 

idle standard?

SLEEPER TRUCKS OPERATED IN CALIFORNIA 

Truck will not be 

equipped with 

automatic idle 

shutdown timer. 

Operator may idle truck’s 

engine for extended periods 

of time, except within 100 

feet of schools or homes. 

Operator may choose to 

park at locations with offboard heating and cooling 

(e.g., IdleAire Technology.) 

Is truck modified with 

an alternative cab 

comfort device that 

meets the proposed 

requirements?

Is truck equipped 

with automatic 5 

minute idle 

shutdown timer? 

Truck is either federally or 

pre-2008 California certified. 

YES

NO

YES

NO

YES

NO

Operator may use this 

technology for cab comfort. 
 ix

Proposed Label Requirements 

Beginning in 2008, trucks equipped with 2007 and subsequent model year PM-trap 

equipped engines and meeting the NOx idling emission standard or equipped with an 

internal combustion APS will be required to have a label affixed to the hood of the truck 

in order for these engines to operate during rest periods in California. The label 

requirements are being proposed to help enforce the idling requirements in the field by 

enforcement personnel. 

Economic Impacts to Businesses 

When the proposed amendments to the new engine and in-use idling ATCM 

requirements take effect in 2008, trucking businesses that own or purchase new trucks 

with sleeper berths may incur additional expenses due to the need to buy cab comfort 

devices to provide sleeper berth climate control and power for accessories. Similarly, 

owners of out-of-state trucks that frequently operate in California may also need to buy 

cab comfort devices to provide sleeper berth climate control and power for accessories. 

However, these expenses will be offset by the savings resulting from reduced fuel use 

and reduced maintenance requirements. Staff estimates these additional costs can be 

recovered within 1 to 2.5 years, depending on the number of idle hours reduced and the 

type of technology used. Therefore, overall the proposed requirements will benefit truck 

owners and operators because of reduced operating costs. 

Air Quality Impacts and Cost-Effectiveness 

To estimate the emission reductions from the proposal, staff assumed pre-2007 model 

year sleeper berth equipped California and out-of-state trucks will use California 

certified off-road or federally certified non-road diesel-fueled APSs and that dieselfueled APSs retrofitted with a level 3 verified PM control strategy will be used for 2007 

and subsequent model year sleeper berth equipped California and out-of-state trucks. 

Statewide emission reductions are estimated to be approximately 46 tons per day (tpd) 

of NOx, 4.2 tpd of ROG, 1930 tpd (0.7 million tons per year) of carbon dioxide (CO2), 

and 0.42 tpd of PM emissions in 2010. For the South Coast Air Basin, the 

corresponding emission reductions are estimated as 18 tpd of NOx, 1.6 tpd of ROG, 

740 tpd (0.3 million tons per year) of CO2, and 0.15 tpd of PM in 2010. 

Staff’s proposal is expected to provide a cost savings to truck owners over the useful life 

of the cab comfort device by reducing the amount of fuel consumed and the truck’s 

maintenance requirements. Under these circumstances, the emission reductions would 

be “free”, and the cost-effectiveness could not be calculated. If cost savings were set to 

zero as a worst case, cost-effectiveness can be estimated and compared to other 

emission control regulations adopted by the ARB. 

For a 2008 and subsequent model year California certified truck equipped with a nonprogrammable engine shutdown system which uses a diesel fueled APS with a level 3 

verified PM trap, the cost-effectiveness is estimated to be $2.00 per pound of NOx plus 

ROG reduced. 
 x

For a 2007 model year truck, the engine would not have the automatic shutdown 

system but the truck would have a PM trap. Thus, use of an APS would subject it to the 

2008 requirement. Retrofitting a 2007 truck with a diesel-fueled APS with a level 3 

verified PM trap produces a cost-effectiveness estimate of $1.98 per pound of NOx plus 

ROG reduced. 

For a 2006 and older model year California truck equipped with a certified diesel-fueled 

APS with no additional PM control, the cost-effectiveness is estimated to be $1.44 per 

pound of NOx plus ROG reduced. 

Fleets have a distribution of truck model years. Taking this into account produces a 

fleet average cost-effectiveness estimated to be $1.51 per pound of NOx plus ROG 

reduced in 2008. These worst-case estimates all compare favorably to the costeffectiveness of other ARB regulations recently adopted. 
 1

I. INTRODUCTION 

Over the last thirty years, the California Air Resources Board (ARB or the “Board”) has 

adopted a number of emission control regulations that have resulted in significant 

emission reductions from both on- and off-road mobile sources. While these regulations 

have greatly improved air quality, many regions of California continue to exceed state 

and federal air quality standards for ozone and fine particulate matter. Therefore, more 

measures need to be taken to improve California’s air quality and to protect the health 

of its citizens. 

California’s plan for reducing the reactive organic gases (ROG) and oxides of nitrogen 

(NOx) emissions that contribute to both ozone and particulate matter (PM) formation, is 

set forth in the 2003 State and Federal Strategy for the California State Implementation 

Plan (2003 SIP). 

 

In 2010, on-road heavy-duty diesel trucks are estimated to account for as much as 28 

percent, or 559 tons per day (tpd), of the statewide mobile source NOx emission 

inventory and nine percent, or 12 tpd, of the statewide mobile source PM emission 

inventory1. This is of particular concern since these estimates already take into account 

the stringent 2007 on-road heavy-duty diesel engine (HDDE) exhaust emission 

standards recently adopted by the ARB and the United States Environmental Protection 

Agency (U.S. EPA). Therefore, more reductions are needed from these sources. 

The proposed regulation has two related, yet distinct, goals. One goal is to reduce 

idling emissions primarily from new sleeper berth equipped trucks (hereinafter referred 

to as “sleeper trucks”) starting with the 2008 model year. Specifically, the proposed 

regulation would require new trucks to meet an emissions standard when idling or have 

a timer system that would automatically shut the engine off after five minutes of 

continuous idling. The manufacturers using timers may provide heating and cooling for 

driver comfort using an alternative technology such as an auxiliary power system (APS). 

Such an alternative technology would have to be comparable, from an emissions 

standpoint, to the proposed idling requirements. 

The other goal of staff’s proposal targets the existing fleet of sleeper trucks, registered 

in both California and out-of-state. For these trucks, the proposed regulation would 

require the truck operator to manually shut down his/her engine after five minutes of 

continuous idling. To provide for cab comfort, the operator may choose to retrofit 

his/her truck with an alternative technology such as an APS which meets specific 

emissions standards. A more detailed description of staff’s proposal is provided below. 

Staff’s proposal amends sections 1956.8 and 2485 of title 13, California Code of 

Regulations (CCR). Section 1956.8 of the CCR specifies exhaust emissions standards 

and test procedures applicable to 1985 and subsequent model year HDDEs. Staff’s 

 

1

 Based on California Almanac Emissions Projection Data (Published 2005). Idle emissions from heavy-duty diesel 

vehicles were adjusted to reflect revised average idle times for medium heavy-duty diesel vehicles. 
 2

proposal would modify this section by requiring new 2008 and subsequent model year 

on-road diesel engines with a gross vehicle weight rating (GVWR) greater than 14,000 

pounds to be equipped with an engine shutdown system that automatically shuts down 

the engine after five minutes of continuous idling. In lieu of the engine shutdown system 

requirement, manufacturers may optionally certify their engines to a NOx idling emission 

standard of 30 grams per hour under loaded, low and high idle operating conditions. 

For purposes of discussion in this document, staff’s proposed modifications to section 

1956.8 are hereinafter referred to as “new engine requirements”. 

Section 2485 of the CCR is an airborne toxic control measure (ATCM) that limits idling 

to no more than five minutes for in-use diesel-fueled commercial vehicles with a GVWR 

greater than 10,000 pounds. However, the ATCM currently exempts sleeper trucks 

when the operator is resting in the sleeper berth and idling the main engine for climate 

control or to power on-board accessories. Starting in 2008, staff’s proposal would 

extend section 2485’s applicability to existing and future sleeper trucks. For purposes 

of discussion in this document, staff’s proposed modifications to section 2485 are 

hereinafter referred to as “in-use idling ATCM requirements”. 

The proposal also allows the use of alternative technologies to supply power needed for 

cab/sleeper comfort and/or other on-board accessories that would otherwise have been 

generated by the continuous idling of the truck’s main engine. These technologies 

include, but are not limited to, internal combustion engine driven APSs and fuel-fired 

heaters. Such technologies would need to comply with defined performance 

requirements set forth in this proposal to operate in California and are also supported by 

the proposed modifications to section 2402, 2424, and 2425 of the CCR. Other 

technologies that do not directly produce emissions, such as battery electric APSs, fuel 

cell APSs, thermal energy storage devices, and power inverter chargers for use with 

battery and grid-supplied electricity are also allowed. Any technology that is not 

identified in this proposal may also be used provided it is approved by the Executive 

Officer. The use of these devices in lieu of operating the truck’s main engine at idle will 

result in significant NOx and carbon dioxide (CO2) emission reductions. Reductions in 

ROG and PM emissions are also expected, but to a lesser degree, depending on the 

alternative technology used. 

The following chapters of the staff report provide background information, a summary of 

the proposed amendments, regulatory alternatives evaluated, an economic impact 

analysis, environmental impact and cost-effectiveness analysis, and conclusions and 

recommendations. 
 3

II. BACKGROUND 

This chapter provides an overview of the applicable vehicle classes included in this 

proposal, a brief description of the truck idling concern, associated emissions, existing 

regulations, and the 2003 SIP commitments. 

A. VEHICLE CLASSES 

The proposed new diesel engine requirements apply to trucks with a GVWR greater 

than 14,000 pounds. Examples of trucks subject to the proposal are line-haul trucks, 

delivery trucks, trash trucks, bulk-hauling trucks, tankers, utility trucks, and construction 

vehicles. 

The proposed changes to the in-use idling ATCM apply to sleeper trucks with a GVWR 

greater than 10,000 pounds. The majority of the sleeper trucks are in the heavy-heavy 

duty diesel vehicle class category (over 33,000 pounds GVWR). 

B. TRUCK IDLING EMISSIONS CONCERNS 

Emissions from idling trucks pose a significant air quality problem. Idling emissions are 

particularly significant at locations such as truck stops, travel centers, rest areas, and at 

warehouse/distribution centers and port terminals where loading and unloading freight 

require long waiting periods. Such locations can experience a very high density of 

trucks idling together for extended periods of time, thereby producing highly localized 

and concentrated emissions. These emissions affect the health of the drivers, truck 

stop, warehouse, and ports personnel, and the neighboring community. The health 

concerns in particular become more serious when such locations are located in low 

income communities that are already disproportionately impacted by air pollution. 

C. EXTENT OF IDLING 

Diesel trucks operate significant periods of time at idle. The amount of idling varies 

widely among trucks depending on season, location, company policy, and driver needs. 

The U.S. EPA estimates a typical long haul sleeper truck to idle approximately 2,400 

hours over the course of a year (U.S. EPA, 2004). While a report by the United States 

Department of Energy (Stodolsky et al., 2000) estimates that long-haul sleeper trucks 

idle for about 1,800 hours per year. Based on these studies, staff used the average of 

the U.S. EPA and the Department of Energy estimates, and thus has assumed that 

sleeper trucks idle for 2,100 hours per year. Normalized over 365 days, the average 

idling time is therefore assumed to be approximately six hours per day. 

The reasons for truck idling vary greatly. Drivers often operate their engines at idle to 

provide cab climate control, to power on-board accessories and/or to keep the engine 

warm to avoid cold-start problems during winter months. Many drivers of sleeper and 

non-sleeper trucks also operate the main engine at idle for extended periods of time 

simply because of habit and to mask outside noise. But according to a pilot survey on 
 4

truck idling trends conducted in Northern California, the majority of drivers operate their 

engines at idle mainly for heating (67 percent) and air conditioning (83 percent) 

purposes (Brodrick et al., 2001). These survey results suggest that if heating and air 

conditioning can be maintained using an alternative idle reduction strategy, truck idling 

emissions in California can be significantly reduced. 

D. FUEL CONSUMPTION 

Besides generating emissions, engine idling also increases fuel consumption, engine 

wear and maintenance costs. Studies have shown that during idling, trucks consume 

approximately 0.4 to 1.6 gallons per hour of fuel depending on engine size, engine 

speed, heating, air conditioning and electrical loads (Lambert et al., 2001; Lim, 2002). It 

should also be noted that during idle operation, drivers sometimes operate their engines 

at elevated engine speeds to provide more power to operate climate control devices 

and on-board accessories, to reduce cab noise and vibration, and to reduce engine 

wear associated with low speed idling. Tests have also shown that as engine speed 

increases, fuel consumption increases proportionally (Lambert et al., 2001; Lim, 2002). 

Assuming an average fuel consumption of one gallon per hour for an idling diesel truck 

engine, staff estimates that in 2005 the diesel fuel consumption due to idling of 

California registered sleeper trucks is approximately 162,000 gallons per day statewide. 

E. EMISSIONS INVENTORY 

Diesel trucks are major contributors to California’s air quality problems. On a per truck 

basis, they emit relatively high levels of NOx and PM emissions, both of which 

contribute to serious public health problems. As previously mentioned, it is projected 

that in 2010, both California and out-of-state registered diesel trucks will contribute 

approximately 28 percent of the statewide mobile source NOx emissions and nine 

percent of the statewide mobile source PM emissions. 

California’s emissions inventory model, EMAFC2002 version 2.2, estimates that, in 

2010, the number of diesel tucks (GVWR greater than 33,000 pounds) on the road on a 

typical day in California to be approximately 180,000 and that 25 percent of these trucks 

come from out-of-state. Furthermore, based on an analysis of the 2002 Vehicle 

Inventory and Use Survey database (U.S. Census Bureau, 2005) 20 percent of the 

California registered diesel trucks are estimated to be sleepers. The majority of the outof-state trucks are sleeper trucks idling for an extended period of time. Staff assumes 

that 90 percent of the out-of-state diesel trucks in California are sleepers. 

Thus, statewide emissions in 2010 from extended idling of California registered sleeper 

trucks are estimated to be 20 tpd of NOx and 0.39 tpd of PM emissions. Similarly for 

the South Coast Air Basin, the 2010 idling emissions from California registered sleeper 

trucks are estimated to be approximately 8 tpd of NOx and 0.14 tpd of PM emissions. 

Statewide emissions in 2010 from extended idling of out-of-state sleeper trucks are 

estimated to be 33 tpd NOx and 0.34 tpd of PM emissions. Similarly for the South 
 5

Coast Air Basin, the 2010 idling emissions from out-of-state trucks are estimated to be 

approximately 13 tpd of NOx and 0.12 tpd of PM emissions. 

F. EXISTING REGULATIONS 

ARB’s 2004 diesel engine standards reduced NOx emissions from these engines by 50 

percent from the 1998 levels (ARB, 1998a). ARB’s 2007/2010 diesel engine 

aftertreatment forcing emission standards will reduce both NOx and PM emissions from 

new engines by another 90 percent (ARB, 2001a). In addition, California also has a 

heavy-duty vehicle inspection program aimed at reducing emissions from the existing 

fleet2. 

While ARB has successfully adopted regulations to reduce emissions from heavy-duty 

diesel engines, it has not, until recently, specifically sought to control idling emissions. 

In December of 2002, ARB adopted an ATCM to limit school bus idling at or near 

schools3

. This ATCM requires a driver of a school bus, transit bus, or other commercial 

vehicle to manually turn off the bus or vehicle engine upon arriving at a school and to 

restart it no more than 30 seconds before departing. In July 2004, ARB adopted an inuse idling ATCM that limits idling of diesel-fueled commercial vehicles and buses to no 

more than five minutes4

. However, this ATCM does not apply to idling sleeper trucks 

that are located further than 100 feet from any restricted area (residential homes and 

schools). 

Section 40720 of the Health and Safety Code requires marine terminals to limit truck 

idling to no longer than 30 minutes. Failure to comply with this requirement subjects the 

marine terminal to a fine of $250 per vehicle per violation. The local air pollution control 

district with jurisdiction over the terminal has the responsibility of enforcing this 

requirement. 

The ARB has also initiated voluntary incentive and demonstration programs to reduce 

idling. For example, the Carl Moyer Program5

 promotes the introduction of APSs as an 

idle reduction device for sleeper trucks by providing monetary incentives for the 

installation costs of APSs. In addition, ARB also provides funds to accelerate the 

deployment of truck stop electrification. One such grant, for example, is the $2 million 

grant fund awarded to IdleAire to subsidize the use of 200 new advanced truck stop 

electrification spaces in the San Joaquin Valley. 

 

2

 California currently has two heavy-duty vehicle inspection programs, the Heavy-Duty Vehicle Inspection Program 

(HDVIP) and the Periodic Smoke Inspection Program (PSIP). Under the HDVIP, heavy-duty diesel trucks and 

buses are tested for excessive smoke emissions and inspected for tampering at random roadside locations, weigh 

stations and fleet facilities. The PSIP compliments the HDVIP by requiring California-based truck and bus fleets 

with two or more HDDVs to annually test their own vehicles to measure smoke opacity and to check for tampering. 

Title 13, California Code of Regulations sections 2180 et seq. and 2190 et seq., respectively. 

3

 Title 13, California Code of Regulations, section 2480. 

4

 Title 13, California Code of Regulations, section 2485. 

5

 An ARB program, implemented in 2000, that provides incentive money to help promote the introduction of 

emission reduction technologies into California. 
 6

G. STATE IMPLEMENTATION PLAN (SIP) 

Although many of the measures in the 1994 ozone SIP have been adopted, federal air 

quality standards will not be attained in many areas of the state by the statutory 

deadlines. As a result, ARB updated the 1994 SIP and generated a revised 2003 SIP. 

The 2003 SIP includes new measures to further reduce emissions and to move towards 

achieving the federal air quality standards for ozone and PM. One on-road heavy-duty 

vehicle measure contained in the 2003 SIP is measure “ON-ROAD HEAVY-DUTY-3.” 

This measure in turn consists of several other control measures such as PM In-Use 

Emission Control, Engine Software Upgrade, On-Board Diagnostics, Manufacturers’ InUse Compliance, and Reduced Idling. It commits to achieve between 1.4 and 4.5 tpd of 

ROG reductions and between 8 and 11 tpd of NOx reductions in the South Coast Air 

Basin in 2010. This proposal is part of measure ON-ROAD HEAVY-DUTY-3 and will 

contribute towards fulfillment of the committed emission reductions in the 2003 SIP. 
 7

III. NEED FOR CONTROL 

As previously mentioned, on-road heavy-duty diesel trucks contribute significantly to the 

statewide NOx and PM emissions inventory. NOx is one of the two primary contributors 

to the formation of ozone and contributes to serious public health issues (ARB, 2001b). 

Diesel PM has been identified by ARB as a toxic air contaminant based on its potential 

to cause cancer (ARB, 1998b), and can also result in other serious health problems 

such as asthma and reduced lung function (ARB, 2001b). 

Besides generating excess ROG, NOx, CO and PM emissions, unnecessary engine 

idling also produces undesirable CO2 emissions. CO2 is one of the major greenhouse 

gas emissions responsible for global warming (ARB, 2002b). 

Staff’s proposal would significantly reduce NOx emissions and associated health risks 

by reducing the time sleeper trucks are operated at idle. The benefits from this proposal 

are particularly significant in low-income communities located close to truck stops, travel 

centers, rest areas, ports, warehouse/distribution centers, and other locations where 

extended truck idling activity occurs. The proposal will also help reduce CO2 emissions 

and the state’s dependence on foreign oil (via reduced fuel consumption). It will also 

result in a net benefit for trucking businesses over the useful life of the truck by saving 

money through improved fuel economy and reduced maintenance requirements. 
 8

IV. SUMMARY OF PROPOSED REQUIREMENTS 

Staff recommends the Board amend Sections 1956.8, 2404, 2424, 2425, and 2485 of 

title 13, CCR, and the incorporated “California Exhaust Emission Standards and Test 

Procedures for 2004 and Subsequent Model Heavy-Duty Diesel Engines and Vehicles”, 

as set forth in Appendices A and B. Staff’s proposal consists of two major components, 

affecting new engines and trucks, and existing engines and trucks. The component that 

targets new engines and trucks would require engine manufacturers to install on new 

2008 and subsequent model year engines a non-programmable engine shutdown 

system or optionally certify engines to a low NOx idling emission limit. The second 

component involves changes to the in-use idling ATCM and affects existing as well as 

future sleeper trucks. The proposed changes would require operators of sleeper trucks 

to comply with the existing five minute idling restriction, beginning in 2008. The 

following sections discuss each element of the proposal in detail, including impacts on 

truck owners and operators, and the available options. 

A. PROPOSED NEW ENGINE REQUIREMENTS 

i. Applicability 

The proposed new engine requirements apply to new California certified 2008 and 

subsequent model year diesel engines installed in trucks with a GVWR greater than 

14,000 pounds. 

The proposed new engine requirements do not apply to gasoline engines or engines 

produced for use in buses (commercial buses as well as school buses), and 

recreational vehicles. Gasoline fueled vehicles are excluded because the hot and cold 

start emissions associated with gasoline engines could cancel out or even exceed the 

benefits from reduced idling. Commercial buses and school buses are excluded 

because they have large volumes and window areas that necessitate operating the 

vehicle’s main engine to power an air conditioning system with high heating and/or 

cooling capacity. The majority of recreational vehicles sold in California are gasolinefueled and are equipped with generators6

. Their contribution to idling emissions is 

negligible and thus these vehicles are also excluded from the proposed requirements. 

ii. Engine Shutdown System 

The effectiveness of anti-idling measures is largely dependent on the effectiveness of 

California’s enforcement of such measures. However, effective enforcement of antiidling measures is challenging since it requires considerable enforcement resources 

throughout the state. Staff believes that anti-idling rules can be an effective emission 

control strategy, if in addition to enforcement, engine technologies are also used. For 

example, a truck equipped with an engine that automatically shuts down after a 

 

6

 According the Recreational Vehicle Industry Association, approximately 95 percent of the recreational vehicles 

sold in California in 2002 are equipped with generators (RVIA, 2003). Based on EMFAC2002 ver2.2, 93 percent of 

these vehicles are gasoline-fueled (ARB, 2003). 
 9

prescribed time period without the assistance of the operator can ensure compliance 

with statewide in-use idle requirements without depending solely on enforcement 

personnel. Requiring a non-programmable engine shutdown system on all new engines 

would significantly reduce extended idling of both new sleeper and non-sleeper trucks, 

and will help ensure compliance with the statewide in-use idling ATCM rule. As these 

new trucks eventually replace the older trucks, the resources needed for an effective 

idling enforcement program will be significantly reduced. 

The proposed new engine requirements would require engine manufacturers to install, 

on new California certified 2008 and subsequent model year diesel engines, an engine 

shutdown system that automatically turns the engine off after five minutes of continuous 

idle operation, or, as an option, control engine emissions during extended idling 

(discussed in section iii below). Engines equipped with the engine shutdown system 

must have systems that are tamper resistant and non-programmable and must include 

the following provisions. 

Conditions for Shutdown 

The engine shutdown system must automatically activate when the truck comes 

to a stop, the transmission is set in the “neutral” or “park” position, and the 

parking brake is engaged. Upon activation, the system will shut down the engine 

after five minutes of continuous engine operation at idle. The requirement that 

the parking brake be engaged as a condition for the system’s activation 

eliminates the possibility of undesirable engine shutdown, such as when the truck 

is stopped in traffic idling for more than five minutes. However, there is a 

possibility that drivers may use this feature to override the engine shutdown 

system. That is, a driver could park a truck without engaging the parking brake 

and operate the engine at idle indefinitely. To prevent this, the proposal would 

require that the engine shutdown system be activated and shut down the engine 

after 15 minutes of continuous idling if the parking brake is not engaged but the 

truck is stopped and the transmission is in neutral or in park. 

Engine Shutdown Reset 

 

The truck operator would be allowed to reset the engine shutdown system timer 

before engine shutdown. A warning signal, such as a light or sound indicator 

inside the truck cabin, may be used to alert the operator up to 30 seconds prior to 

engine shutdown. The operator could then reset the engine shutdown system by 

momentarily changing the position of the accelerator, clutch, or brake pedal or 

any other mechanism only during the last 30 seconds of the five-minute 

shutdown time limit (or the last 30 seconds of the 15 minutes when the parking 

brake is not engaged). This will allow the truck operator to continue operating 

the engine at idle as long as the truck is being driven. 
 10

Power Take-Off Devices

The engine shutdown system could be overridden when the engine is operating 

power take-off (PTO) equipment. A PTO device uses the truck’s engine to 

transfer power to auxiliary equipment. So during periods when the truck’s engine 

is “working” while it is idling, the engine shutdown system would not be activated. 

Examples of trucks with PTO equipment include trash trucks, cement mixers, 

mobile cranes, dump trucks, and vehicles with conveyors or other loading or 

unloading devices. The proposal does not consider equipment such as the 

truck’s air conditioning system and on-board accessories (e.g., a television, 

microwave, etc.,) as PTO equipment. 

Engine Warm Up 

The engine shutdown system could also be overridden to warm up the engine if 

the engine coolant temperature is below 60°F. Thus, the engine shutdown timer 

would be activated once the coolant temperature reaches 60°F. The engine 

coolant temperature must be measured using the engine’s existing engine 

coolant temperature sensor designed for engine protection. However, a 

manufacturer may request the Executive Officer’s approval to use other methods 

of measuring the engine coolant temperature. 

Enforcement Mechanism 

To discourage tampering and to detect malfunctions of engines, the Board, in 

July of 2005, adopted On-Board Diagnostic (OBD) system requirements for 

heavy-duty trucks that will include monitoring of all emission control systems, 

including tracking the truck engine run time at idle and monitoring proper 

performance of sensors controlling the engine shutdown system. The OBD 

system requirements will be implemented starting with 2010 and later model year 

diesel engines and will monitor the proper function of the engine shutdown 

system. The OBD system will log fault codes if any sensor malfunctions. The 

fault codes can then be downloaded from the OBD system and inspected by 

ARB field inspectors in current or future heavy-duty truck roadside inspection 

programs. Field inspectors that connect to the truck’s OBD system will also be 

able to analyze the amount of engine run time at idle, providing another way to 

evaluate whether the engine shutdown system is malfunctioning or has been 

tampered with. 

Furthermore, because engine manufacturers must include a statement in their 

applications for certification that their engines will comply with the engine 

shutdown system requirement, violations of this requirement are enforceable 

through applicable penalty provisions of the Health and Safety Code. 
 11

iii. Optional NOx Idling Emission Standard 

During the development of this proposal, several engine manufacturers indicated that 

NOx aftertreatment devices may to some degree reduce NOx idling emissions7 and 

requested an option to certify engines to a new NOx idling emission standard as an 

alternative to meeting the engine shutdown system requirements. Another method 

suggested by the manufacturers was to take advantage of other strategies, such as 

advanced combustion processes or operational controls such as cylinder deactivation, 

to reduce NOx emissions during idling. 

To accommodate the engine manufacturer’s request, staff’s proposal includes an 

optional NOx idling emission standard and test procedure. To determine the 

appropriate emission standard, staff evaluated currently available technologies that 

could provide all the operator needs as an alternative cab comfort device. Staff 

identified the diesel-fueled APS as the most likely and cost-effective cab comfort 

technology in 2008, when this proposal is to be implemented. The standard was based 

on the average NOx emission level of 2005 certification test data of off-road diesel 

engines used in APSs (engines with power ratings between 5 to 19 kilowatts). The 

proposed standard takes into account what the average NOx emissions levels will be 

over the useful life of the engine by incorporating a deterioration factor as part of the 

certification emission level. Staff’s analysis resulted in a proposed optional NOx 

emission standard of 30 grams per hour. This standard is based on an APS providing 5 

kilowatts of power, typically the peak power demand to provide all the necessary cab 

comfort and on-board accessory demands. The 30 grams per hour standard will 

provide significant NOx emission reduction, when comparing average NOx idling 

emissions of 165 grams per hour from late model truck engines, and will be equivalent 

to trucks operating a diesel-fueled APS as an alternative cab comfort device. A truck 

equipped with an engine certified to the optional NOx idling emission standard would 

also be required to have a label affixed to its hood that would permit the truck engine to 

idle beyond the five-minute idle time limit requirement imposed by the amendments 

made to the in-use idling ATCM (discussed in section B below). 

The test procedure was developed to account for the varied operation of truck engines 

at idle. Typically, truck operators elevate the idle speed to provide more power for cab 

comfort and accessory devices. Higher engine speed also reduces truck vibration when 

idling and thus provides more comfort for the operator during rest periods. The test 

procedure requires engine testing at “curb idle” and at 1100 revolutions per minute 

(rpm) idle speed, under loaded and unloaded conditions (described in more detail 

below). 

 

7

 NOx aftertreatment devices, such as NOx adsorbers, typically operate most efficiently when exhaust temperatures 

are above 200°C (MECA, 2000). Exhaust temperatures during extended idling typically reach no more than 150°C 

(Hallstrom, 2005). Thus, while it is known that NOx adsorbers can significantly reduce NOx emissions, it is unclear 

at this time what level of reductions can be achieved by using NOx adsorbers during extended idling conditions. 
 12

Certification Test Procedure 

The proposed test cycle for demonstrating compliance with the optional NOx 

idling standard utilizes an engine dynamometer operated in accordance with a 2-

mode steady-state test cycle summarized in Table 1. Staff believes this test 

cycle accurately represents the range of sleeper and non-sleeper truck idling 

operations commonly practiced by truck operators. 

Mode 1 involves operating the engine at its manufacturer’s recommended curb 

idle speed. An engine load is applied and must include truck power demands for 

operating engine accessories, such as the engine cooling fan, alternator, coolant 

pump, air compressor, engine oil and fuel pumps and any other engine 

accessory operated during engine curb idle. Mode 1 does not include truck 

power demands to operate the air conditioning compressor or on-board electrical 

accessories such as a television, refrigerator, microwave, computer, etc. 

Mode 2 involves operating the engine on a dynamometer at a speed of 

1100 rpm. The engine load applied must include truck power demands to 

operate engine accessories at 1100 rpm, power demands to operate the air 

conditioning compressor at maximum capacity, and an additional load of 2kW to 

account for power demands for operating on-board accessories such as a 

television, refrigerator, microwave, computer, etc. 

Table 1: Certification Test Cycle 

Mode Engine Speed 

 (rpm)a

Time in mode 

(seconds) Engine Load 

1 

Manufacturer 

Recommended 

Curb idle 

1800 

Vehicle power demands to operate 

engine accessories at curb idle. Engine 

accessories include, but are not limited 

to, cooling fan, alternator, fuel and oil 

pumps, coolant pump, air compressor, 

etc., (excluding air conditioning 

compressor and on-board accessories) 

2 1100 1800 

Vehicle power demands to operate (1) 

engine accessories (same as for mode 

1) at 1100 rpm, (2) the air conditioning 

compressor operating at maximum 

capacity, and (3) an additional 2 kW to 

take into account on-board electrical 

accessories such as television, 

computer, etc. 

a

 revolutions per minute 
 13

Exhaust emissions measurements are taken under hot stabilized conditions. If 

the engine is cold, the engine would be preconditioned prior to taking any 

emission measurements by operating it on an engine dynamometer at any speed 

above peak-torque speed and between 65 to 85% of mapped power until the 

engine coolant temperature stabilizes. Once the engine coolant temperature 

stabilizes, emission measurements would be taken continuously for a minimum 

of 30 minutes for each mode. For each test mode, modal average emissions are 

then calculated for each regulated pollutant. The calculated average NOx 

emissions must then be less than 30 grams per hour. Further details on this 

procedure can be found in Appendix B. 

iv. Impact on Truck Operators 

2008 and Subsequent Model Year California Certified Truck Engines 

If the truck engine is equipped with the non-programmable engine shutdown system, 

the truck operator would not be able to idle the truck engine for long periods of time, 

regardless of whether the truck operator’s engine idling needs occur in California or outof-state. This means that sleeper trucks equipped with the engine shutdown system 

would need to provide other methods for heating/cooling the cabin and powering 

accessories when the truck is not being driven and the operator is resting in the sleeper 

berth. Currently available methods include the use of an internal combustion APS, 

battery electric APS, fuel-fired heater, thermal energy storage system, and/or a power 

inverter charger with an electrically driven air conditioning system. The engine or truck 

manufacturer may equip the truck with such a cab comfort device. If not offered by the 

manufacturer, the owner may choose to equip his/her truck with an aftermarket cab 

comfort device. However, in order to operate in California, cab comfort devices that 

produce emissions would need to comply with defined performance requirements set 

forth in this proposal (see section C.i., below). Other alternatives, that do not require 

installation of any cab comfort device, include parking at a truck stop that offers an offboard air conditioning, heating and power, such as offered by IdleAire Technologies 

(see section C.ii.2., below). 

If an owner purchases a truck equipped with a diesel engine meeting the optional NOx 

idling emission standard, the engine would not have an engine shutdown system. 

Operators of such trucks would be allowed to idle the main engine continuously to 

provide cab comfort and electrical power during rest periods and would not need to 

install alternative cab comfort devices. However, they would still be subject to the 

existing five minute idling restriction when the truck is located within 100 feet of a 

restricted area and the truck would be required to have a label affixed to its hood (see 

section D, Label Requirements). It should be noted that staff does not expect this 

option to become widely available to truck owners/operators before the 2010 timeframe 

since NOx aftertreatment devices are not anticipated to be employed until 2010 and 

other engine idling controls/strategies have not yet been fully demonstrated. 
 14

2008 and Subsequent Model Year Federally Certified Truck Engines 

It is expected that most of the 2008 and subsequent model year out-of-state trucks will 

be equipped with a federally certified truck engine that does not incorporate the nonprogrammable engine shutdown system requirements or meet the optional NOx idling 

emission standard. Operators of such trucks would be able to operate their truck 

engine continuously at idle outside of California. However, they would not be able to 

continuously idle their truck engine in California as he/she would also be subject to the 

five minute idling restriction under the proposed changes to the in-use idling ATCM 

requirements, discussed in section B, below. As a result, 2008 and subsequent model 

year federally certified trucks that operate and rest for extended periods in California 

would also need an alternative cab comfort device to provide for cab cooling/heating 

and power for accessories during these rest periods. These cab comfort devices are 

the same as the ones identified above for California certified trucks, and include an 

internal combustion APS, battery electric APS, fuel-fired heater, thermal energy storage 

system, and/or a power inverter charger with an electrically driven air conditioning 

system. Other alternatives, that do not require installation of any cab comfort device, 

include parking at a truck stop that offers off-board air conditioning, heating and power, 

such as offered by IdleAire Technologies. Similarly as required for California certified 

truck engines, in order to operate in California, cab comfort devices that produce 

emissions would also need to comply with defined performance requirements set forth 

in this proposal (see section C below for details). Also, to comply with the in-use idling 

ATCM requirements, a truck equipped with internal combustion engine APS will be 

required to have a label affixed to the hood of the truck in order to operate the APS in 

California (see section D below for details). 

B. PROPOSED AMENDMENTS TO IN-USE IDLING ATCM AFFECTING 

EXISTING TRUCKS 

i. Applicability

The proposed amendments to the in-use idling ATCM apply to existing and future 

sleeper trucks greater than 10,000 pounds GVWR, beginning in January 1, 2008. The 

in-use idling ATCM also applies to out-of-state registered trucks that operate in 

California. Emergency vehicles performing emergency services, military tactical 

vehicles during training, and vehicles with engines operating power take-off (PTO) 

equipment (a more detailed description of a PTO device is provided in section A.ii of this 

Chapter) are exempted. Other exemptions are specified in the existing in-use idling 

ATCM, section 2485 of the CCR. 

ii. Idling Restriction 

The existing in-use idling ATCM, section 2485 of the CCR, prohibits the driver of a 

diesel-fueled commercial truck with a GVWR greater than 10,000 pounds from idling the 

truck’s main engine for more than five minutes at any location. The existing rule 
 15

exempts sleeper trucks from this prohibition if they are located more than 100 feet from 

a restricted area. This exemption was provided at the time the rule was adopted 

because although staff had identified the diesel-fueled APS as a reliable cab comfort 

technology that would provide emission benefits on 2006 and older model year trucks, 

there were unresolved issues related to what these benefits might be when compared to 

“cleaner” 2007 and subsequent model year trucks. Therefore, staff recommended to 

the Board to delay consideration of sleeper trucks until 2005 in order to thoroughly 

evaluate all commercially available options to main engine idling. 

Staff is now proposing to remove this exemption so that sleeper trucks would have to 

comply with the five-minute idling restriction at all times and at any location starting on 

January 1, 2008. Staff’s proposal to remove the exemption is based on the current 

availability of cost-effective alternatives to truck idling and the resulting emission 

benefits. 

Starting in 2007, trucks will be “cleaner” as a result of new emission standards that will 

reduce PM emissions by 90 percent or more using exhaust aftertreatment devices such 

as particulate traps. However, when the proposed no-idling requirements take effect in 

2008, diesel-fueled APSs will be certified to the Tier 4 off-road standards, which are less 

stringent than the 2007 aftertreatment based diesel PM emission standards. Thus, to 

control the expected excess PM emissions that may result from operating a dieselfueled APS as an alternative to idling the truck’s trap-equipped engine, the proposal 

requires, starting January 1, 2008, that diesel-fueled APSs installed on trucks equipped 

with 2007 and subsequent model year diesel engines be retrofitted with a PM control 

strategy verified as a "level 3" device (i.e., achieve 85% PM reduction efficiency). 

Based on discussions with PM trap manufacturers, staff also believes that the proposed 

additional PM control requirement for diesel-fueled APSs is feasible within the 

timeframe of the proposed regulation. 

Staff’s proposal also allows the use of other strategies in combination with a dieselfueled APS that result in an equivalent reduction in PM emissions. This could include, 

for example, installing a power inverter/charger with an electrically driven air 

conditioning and heating system in combination with the use of a diesel-fueled APS. A 

truck equipped with such an APS would also be required to have a label affixed to its 

hood to operate the APS. As previously mentioned, the labeling requirements are 

described in Section D of this chapter. 

PM emissions from Tier 4 certified APSs are usually lower or, at worst, are the same as 

idling PM emissions from 2006 or older model year truck engines8

. Therefore, the 

proposal allows the use of any Tier 4 certified APS with no additional PM emission 

control requirements with pre-2007 model year truck engines. 

 

8

 A Tier 4 certified diesel-fueled APS emitting at the certification PM emission standard of 0.4 g/kW-hour and 

providing an average power of 2.7 kW produces about 1.08 grams per hour of PM emissions. This is lower than the 

estimated average idling PM emission rate of 1.59 grams per hour for a 2006 model year truck engine. 
 16

iii. Impact on Truck Operators 

The proposed changes to the in-use idling ATCM will apply to existing and future 

sleeper trucks, including those registered out-of-state. Starting on January 1, 2008, it 

will require operators of sleeper trucks to shut down their engine before the five-minute 

idle time limit is reached and will affect truck operators of California and federal certified 

engines in different ways. The discussion that follows provides details on how truck 

operators will be impacted. Following the discussion, a summary of these impacts is 

graphically depicted in two flow chart diagrams, Figures 1, 2 and 3. 

Operators of 2008 and Subsequent Model Year California Certified Diesel Engines 

Under staff’s proposal, California certified trucks with 2008 and subsequent model year 

diesel engines will be equipped with either 1) a non-programmable engine shutdown 

system, or 2) an engine certified to the optional NOx idling emission standard. 

Trucks equipped with the engine shutdown system will automatically shut down the 

engine after five minutes of continuous idling, regardless of whether the truck is in 

California or in another state. In cases where owners of such trucks rest for extended 

periods (such as owners of sleeper trucks), it is likely that the owner will want to equip 

his/her truck with cab comfort devices. Currently available cab comfort devices include 

the use of an internal combustion APS, battery electric APS, fuel-fired heater, thermal 

energy storage system, and/or a power inverter charger with an electrically driven air 

conditioning system. The engine or truck manufacturer may equip the truck with such a 

cab comfort device. If not offered by the manufacturer, the owner may choose to equip 

his/her truck with an aftermarket cab comfort device. However, in order to operate in 

California, cab comfort devices that produce emissions would need to comply with 

defined performance requirements set forth in this proposal (see section C.i., below). 

Also, to comply with the in-use idling ATCM requirements, a truck equipped with an 

internal combustion engine APS will be required to have a label affixed to the hood of 

the truck in order to operate the APS in California. Other alternatives, that do not 

require installation of any cab comfort device, include parking at a truck stop that offers 

off-board air conditioning, heating, and power, such as offered by IdleAire Technologies 

(see section C.ii.2., below). 

Trucks equipped with engines certified to the optional NOx idling emission standard will 

not be equipped with an automatic engine shutdown system. Those trucks will not shut 

down during continuous idling and will not require the owner to have any alternative cab 

comfort device installed when he/she rests in their truck during layover hours. Thus, the 

operator of such a truck will not be required to change the way they currently operate 

their truck during layover hours. However, to comply with the in-use idling ATCM 

requirements in California, the engine or truck manufacturer will need to ensure that a 

label is provided and properly affixed to the hood of the truck in order to operate the 

main engine at idle for more than five minutes. 
 17

Also, all 2008 and subsequent model year trucks equipped with fuel-fired heaters will be 

required to meet the LEV II fuel-fired heater emission requirements (see section C 

below) to operate them in California. 

Operators of 2008 and Subsequent Model Year Federal Certified Diesel Engines 

Trucks equipped with federal certified engines will not be equipped with an automatic 

engine shutdown system or have engines that meet the optional NOx idling emission 

standard. Those trucks will not shut down during continuous idling and will not be 

affected by staff’s proposal when they are operated outside of California. However, 

when operating in California, the operators will also be subject to the in-use idling ATCM 

requirements. The in-use idling ATCM rule will require the operator of a federally 

certified truck to manually shut down his/her engine after five minutes of idling. Thus, 

operators of out-of-state trucks that want to rest in their truck during layover hours in 

California will need an alternative cab comfort device to provide for cab cooling/heating 

and power for accessories during these rest periods. These cab comfort devices are 

the same as the ones identified above for California certified trucks, and include an 

internal combustion APS, battery electric APS, fuel-fired heater, thermal energy storage 

system, and/or a power inverter charger with an electrically driven air conditioning 

system. Other alternatives, that do not require installation of any cab comfort device, 

include parking at a truck stop that offers off-board air conditioning, heating and power, 

such as offered by IdleAire Technologies. 

Similarly as required for 2008 and subsequent model year California certified trucks, in 

order to operate in California, cab comfort devices that produce emissions would also 

need to comply with defined performance requirements set forth in this proposal (see 

section C below for details). A truck equipped with an internal combustion engine APS 

will be required to have a label affixed to the hood of the truck in order to operate the 

APS in California. 

Also, all 2008 and subsequent model year trucks equipped with fuel-fired heaters will be 

required to meet the LEV II fuel-fired heater emission requirements (see section C 

below) to operate them in California. 

Operators of 2007 Model Year California or Federal Certified Diesel Engines 

Beginning in 2008, operators of trucks equipped with California or federal certified 2007 

model year diesel engines will be required to manually shut down their idling engines 

after five minutes in California to comply with staff’s proposed amendments to the in-use 

idling ATCM rule. These trucks will not be equipped with a non-programmable engine 

shutdown system, nor will they be equipped with engines meeting the optional NOx 

idling emission standards. Owners will need to retrofit their truck with a cab comfort 

device if they plan to rest in their truck during layover hours in California. Currently 

available cab comfort devices, as previously mentioned include the use of an internal 

combustion APS, battery electric APS, fuel-fired heater, thermal energy storage system, 

and/or a power inverter charger with an electrically driven air conditioning system. 
 18

Other alternatives, that do not require installation of any cab comfort device, include 

parking at a truck stop that offers off-board air conditioning, heating, and power, such as 

offered by IdleAire Technologies (see section C.ii.2., below). 

Because a truck equipped with a 2007 model year diesel engine is also equipped with a 

PM aftertreatment system, an owner who chooses to install a diesel-fueled APS as a 

cab comfort device will also need to make sure the APS meets additional PM emission 

control requirements, specified in section C below, if it is to be operated in California. 

This requirement is meant to prevent an over-all increase in PM emissions from trucks 

equipped with 2007 diesel engines if owners choose to meet the proposed in-use idling 

ATCM by installing a diesel-fueled APS. A truck equipped with an internal combustion 

engine APS will be required to have a label affixed to the hood of the truck in order to 

operate the APS in California. 

Also, beginning in 2008, all 2007 model year trucks equipped with fuel-fired heaters will 

be required to meet the LEV II fuel-fired heater emission requirements (see section C 

below) to operate them in California. 

Operators of 2006 and Older Model Year California or Federal Certified Diesel 

Engines 

Beginning in 2008, operators of trucks equipped with California or federal certified 2006 

and older model year diesel engines will be required to manually shut down their idling 

engines after five minutes in California to comply with staff’s proposed amendments to 

the in-use idling ATCM rule. These trucks will not be equipped with a nonprogrammable engine shutdown system, nor will they be equipped with engines 

meeting the optional NOx idling emission standards. As with owners of 2007 trucks, 

owners of 2006 and older trucks will need to retrofit their truck with a cab comfort device 

if they plan to rest in their truck during layover hours in California. As previously 

mentioned, currently available cab comfort devices include the use of an internal 

combustion APS, battery electric APS, fuel-fired heater, thermal energy storage system, 

and/or a power inverter charger with an electrically driven air conditioning system. 

Other alternatives, that do not require installation of any cab comfort device, include 

parking at a truck stop that offers an off-board air conditioning, heating, and power, such 

as offered by IdleAire Technologies (see section C.ii.2., below). 

Unlike the requirements for 2007 and subsequent model year PM trap-equipped trucks, 

owners of trucks with 2006 and older model year diesel engines who choose to install 

diesel-fueled APSs will not need to comply with any additional PM emission 

requirements. As previously mentioned, this is because trucks equipped with 2006 and 

older model year diesel engines are not equipped with a PM aftertreatment system and 

thus the PM idling emissions from those engines are the same or greater than the 

emissions from diesel-fueled APSs. Also, 2006 and older trucks will not be required to 

have a label on the truck hood to operate their APS. For those trucks equipped with 

fuel-fired heaters, they will also not be required to meet the LEV II fuel-fired heater 

emission requirements. 
 19

As previously mentioned, the following flow chart diagrams (Figures 1, 2, and 3) 

graphically summarize how truck operators will be impacted by staff’s proposal. As 

shown, the impacts will differ somewhat, depending on the model year of the 

truck/engine and whether the truck is registered in California or out-of-state. 
 20

Certified to the low NOx idle standard? 

2008 OR NEWER CALIFORNIA TRUCK 

Truck will not be 

equipped with automatic idle 

shutdown timer.

YES

Operator may idle truck’s engine for extended periods of time, except within 100 feet of schools or homes. 

Truck will be equipped with automatic idle shutdown timer 

NO

Truck engine automatically shuts down after 5 minutes of idling 

Operator may choose to park at locations with off-board heating and cooling (e.g., IdleAire Technology.) 

YES

Operator may use this technology for cab comfort. 

YES

YES

YES

YES

YES

Figure 1: Impacts on Operators - 2008 or Newer California Truck 

Is truck modified with an alternative cab comfort device? 

NO
 21

2007 AND NEWER OUT-OF-STATE TRUCKS 

AND 2007 CALIFORNIA TRUCKS

Operator must manually shut down the truck’s engine after 5 minutes of idling 

YES

YES

Figure 2: Impacts on Operators – 2007 and Newer Out-of-State Trucks and 2007 California Trucks

NO

Operator may choose to park at locations with off-board heating and cooling (e.g., IdleAire Technology.) 

Operator may use this technology for cab comfort. 

YES

YES

YES 

Is truck modified with an alternative cab comfort device? 

YES
 22

PRE-2007 OUT-OF-STATE AND 

CALIFORNIA REGISTERED TRUCKS

Figure 3: Impacts on Operators - Pre-2007 Out-of-State and California Registered Trucks 

Operator must manually shut down the truck’s engine after 5 minutes of idling 

YES

YES

NO

Operator may choose to park at locations with off-board heating and cooling (e.g., IdleAire Technology.) 

Operator may use this technology for cab comfort. 

YES

YES

YES 

Is truck modified with an alternative cab comfort device? 

YES
 23

C. PROPOSED EMISSION PERFORMANCE REQUIREMENTS FOR CAB 

COMFORT DEVICES 

When the proposed in-use idling and new engine requirements take effect in 2008, staff 

expects operators of sleeper trucks will use some type of alternative cab comfort 

technology to provide power for sleeper berth climate control, engine heating, and 

electrical power to charge batteries and operate on-board accessories. Some of the 

commonly used, presently commercially available cab comfort technologies capable of 

providing some or all of this power include devices such as an internal combustion APS, 

battery electric APS, fuel-fired heater, thermal energy storage system, and/or a power 

inverter charger and electrically driven air conditioning system with truck stop 

electrification9 (U.S. EPA, 2005). The proposal allows the use of such alternative cab 

comfort devices. However, some of these devices have associated emissions that must 

be evaluated and compared to emissions generated from the main engine under idling 

conditions to ensure the devices do not emit greater emissions than operating the main 

engine. Thus, staff proposes the following emissions performance requirements for 

some of the cab comfort devices. 

Auxiliary Power Systems 

In order to operate in California, internal combustion engines used in APSs must 

currently comply with applicable California off-road or federal non-road emission 

standards and test procedures for their fuel type and horsepower category. Staff 

proposes that diesel-fueled APSs installed on PM trap-equipped 2007 and 

subsequent model year diesel trucks must also meet additional PM controls 

because PM emissions from Tier 4 certified off-road diesel engines (less than 19 

kW ratings) are expected to be higher than the PM emissions from an idling PM 

trap-equipped 2007 model year diesel engine10. Therefore, diesel-fueled APSs 

installed on trucks equipped with 2007 and subsequent model year diesel 

engines will be required to control emissions by either equipping the APS with a 

level 311 verified PM control strategy or by integrating the APS’s exhaust system 

with that of the truck’s so that the APS’s PM emissions are controlled by the 

truck’s PM trap. Subject to the Executive Officer’s advance approval, 

manufacturers may also use other procedures to demonstrate an equivalent level 

of emissions compliance (compared to a level 3 verified PM control strategy). 

Battery electric and fuel cell APSs have recently been developed and are 

inherently emissions free. Battery electric APSs, in particular, are currently 

commercially available and can provide the same performance as diesel-fueled 

 

9

 A comprehensive list with detailed information of commercially available alternative technologies is available at 

the U.S. EPA website at http://www.epa.gov/otaq/smartway/idlingtechnologies.htm. 

10 2007 and subsequent model year on-road HDDEs must comply with a PM exhaust emission standard of 0.01 gram 

per brake-horsepower-hour. 

11 The PM trap verification procedure and in particular, the level 3 verification level, are specified in sections 2700 

to 2710 of title 13, CCR.
 24

APSs. For example, Idling Solutions 9000 is a heavy-duty battery powered APS 

reportedly capable of providing power for cab comfort and on-board accessories 

for 8 to 15 hours between charges. Approximately 120 of these systems are 

currently installed on various fleets including J.B. Hunt Transportation Services, 

Swift Transportation, John Christner Trucking, Motor Lines, Inc., Wild West 

Express, etc. (Jay, 2005). Fuel cell APSs are presently not commercially 

available but are being demonstrated with some truck fleets. 

Fuel-Fired Heaters 

Beginning in 2008, staff proposes that 2007 and subsequent model year trucks 

operate only fuel-fired heaters that comply with the requirements specified in the 

Low Emissions Vehicle program (LEV II) regulations12 in California. The LEV II 

regulations require fuel-fired heaters to meet the Ultra Low Emission Vehicle 

exhaust emission standards for light duty vehicles. However, unlike the LEV II 

program requirement that limits the operation of fuel-fired heaters to ambient 

temperatures of 40oF or less, the proposed regulation would allow the operation 

of fuel-fired heaters at any ambient temperature. Several manufacturers currently 

produce fuel-fired heaters for heavy-duty trucks that meet the proposed 

requirement. 

Other Idle Reduction Devices 

In addition to the above mentioned technologies, other devices may also be used 

to supply power that would otherwise be generated by idling the truck’s main 

engine. Such devices could include, for example, thermal energy storage 

devices or power inverter chargers for use with batteries and/or grid supplied 

electricity. Other devices, not identified here, could also be used, subject to the 

Executive Officer’s advance approval. 

D. LABELING REQUIREMENTS 

Engine Labeling Requirements 

In order to clearly identify compliant diesel engines, staff proposes that each truck 

engine be equipped with a permanent label indicating that the subject engine complies 

with the California regulations. Currently, engine manufacturers produce the same 

engine for all 50 states and therefore produce and affix the same engine label on all 

diesel engines. The existing engine label indicates that the engine conforms to both 

U.S. EPA and California regulations. Staff’s proposed requirement would not modify a 

manufacturer’s existing engine labeling practice for diesel engines sold in California, but 

will indirectly require a modification of the engine label placed on federally certified 

diesel engines for sale outside of California, unless federally certified engines also 

 

12 The standards are specified in title 13, CCR, section 1961(a)(15) and (d), or in Part I.E.1.13 of the “California 

Exhaust Emission Standards and Test Procedures for 2001 and Subsequent Model Passenger Cars, Light-Duty 

Trucks and Medium-Duty Vehicles” (adopted August 5, 1999, last amended in May 28, 2004) 
 25

comply with the proposed requirements. Therefore, unless federally certified diesel 

engines also meet the proposed requirements, engine labels for federally certified 

engines cannot state that the engine conforms to California regulations. This 

requirement is proposed to serve as an effective tool for in-use compliance testing and 

other enforcement programs. 

Vehicle Labeling Requirements 

The proposal would also require that engine manufacturers, original vehicle equipment 

manufacturers (OEM), or internal combustion engine APS manufacturers, as applicable, 

to produce and affix a standardized permanent label to the hood of the truck. This 

vehicle label would aide enforcement personnel in clearly and easily identifying diesel 

engines and diesel trucks equipped with APSs that comply with the proposed 

requirements. Staff therefore proposes that a standardized label be affixed on: (1) 

trucks equipped with an engine certified to the proposed optional NOx idling emission 

standard, and (2) trucks produced or retrofitted with an internal combustion engine APS 

that meets the proposed requirements applicable to APSs. 

The standardized labels would be required to have the following characteristics: 

1. oval in shape 

2. minimum dimensions of 6 inches wide and 4 inches high 

3. permanently attached and easily destroyed or defaced upon removal 

4. includes a hologram (to prevent counterfeit labels) 

Figures 4 and 5 are facsimiles of the proposed labels. Figure 6 shows an example of 

the hologram that would be embedded within the proposed labels. For new engines 

certified to the proposed optional NOx idling emission standard or engines equipped 

with an integrated engine-APS exhaust system for which the engine manufacturer is 

responsible, the engine manufacturer will be responsible for producing the labels and 

supplying them to the OEM. The OEM would then affix the label to the hood of the 

truck. For aftermarket internal combustion engine APSs that meet California 

requirements, the aftermarket manufacturer would be responsible for producing the 

label and affixing it to the hood of the truck if installed by the APS manufacturer. If the 

APS manufacturer does not install the APS, the APS manufacturer would supply the 

label to the party that installs the APS (OEM or any other APS installer). 
 26

Figure 4. Label for an engine meeting the optional NOx standard 

Figure 5. Label for an APS with additional PM control 

Figure 6. Hologram 

I

CERTIIFIIED

CLEAN IIDLE

VERIIFIIED

CLEAN APS
 27

V. TECHNOLOGICAL FEASIBILITY 

Truck idling can be significantly reduced by using currently available idle control 

technologies. Some of these technologies can also provide sleeper/cab heating and 

cooling, heat for engine warming, and electrical power for battery charging and onboard accessories. Each technology has its advantages and drawbacks. These 

technologies include electronically controlled idle engine limiters, on-board auxiliary 

devices, and grid-supplied electrical power. 

A. ENGINE SHUTDOWN DEVICES 

Electronic engine shutdown devices are software based idle limit controls and are 

standard features in most commercially available on-road heavy-duty engines. These 

systems are built into the engine’s electronic control software and enable the engine to 

shut down automatically if the engine idles more than the programmed time. For 

example, Detroit Diesel Corporation’s system can be programmed to shut down 

automatically between 2 to 100 minutes, Cummins’ system can be programmed to shut 

down between 2 to 1440 minutes, and Caterpillar’s system can be programmed to shut 

down between 3 to 60 minutes. These systems can also electronically turn off the 

ignition switch to avoid battery discharge that may occur if accessories, such as lights 

and/or the radio, were left in the “on” position during engine shutdown. Although 

shutdown systems are available as standard features in modern electronically controlled 

engines, in most cases fleet owners and operators do not activate or program these 

systems to limit idling. All features of the engine shutdown system required by this 

proposal, such as overriding the system by pressing the gas or clutch pedal, overriding 

the system if the engine is in PTO mode, conditions for activation of the system, etc., 

are currently available in modern electronically controlled engines. Therefore, with only 

minor modifications in the programming of the electronic control software to prevent 

adjustment or tampering, the key requirement in staff’s proposal can already be met 

with currently available engine shutdown systems. 

B. OPTIONAL NOx IDLING STANDARD 

The proposed optional NOx emission standard may be met with engines equipped with 

NOx catalysts. However, this may require a supplemental heat source to raise the 

exhaust temperatures to a level that would enable the catalyst to sufficiently reduce 

NOx emissions, since exhaust temperatures during extended idling are generally lower 

than the catalyst’s light-off temperatures. Advanced combustion processes, operational 

controls such as cylinder deactivation and/or other idling emission control strategies 

may also be used to achieve the proposed NOx idling emission standard. An engine 

manufacturer would be required to demonstrate its engines’ compliance with the 

proposed optional NOx idling standard, on average, using the test cycle described in 

section A of Chapter IV, without increasing other criteria pollutant emissions such as 

PM, ROG, and CO. 
 28

Staff does not expect that engine manufactures will certify to the optional NOx idling 

emission standard before the introduction of 2010 model year diesel engines. This is 

because, until that time, it is unlikely that manufacturers will equip their engines with 

NOx aftertreatment devices capable of meeting the proposed emission standard. 

Nevertheless, the option to certify to a NOx idling emission standard is being proposed 

at the request of several engine and truck manufacturers as an alternative to requiring a 

non-programmable engine shutdown system. 

C. ALTERNATIVES TO IDLING 

i. On-Board Auxiliary Devices 

On-board auxiliary devices are truck mounted and can supply some or all of the power 

for necessities that would otherwise be generated by idling the truck’s engine. The 

most widely used on-board auxiliary devices on sleeper trucks are diesel-fueled APSs, 

fuel-fired heaters, and inverter chargers. However, newer on-board based auxiliary 

devices are also currently being developed and introduced to the market. Examples 

include battery electric APSs and cold storage systems. Fuel cell-based APSs are also 

being developed and are currently in the demonstration stage. 

1. Auxiliary Power Systems 

Most currently available APSs use a small internal combustion engine equipped with a 

generator/alternator to provide climate control, heat to the engine for cold weather 

starting, 12-volt DC electrical power to charge the batteries and 110-volt AC power for 

on-board accessories. Most of the APSs currently used as alternatives to idling are 

diesel-fueled and typically use fuel from the truck’s fuel system. The fuel consumption 

of diesel-fueled APSs ranges from 0.08 to 0.3 gal/hr (Stodolsky et al., 2000). This 

represents a significant fuel savings (and lower CO2 emissions) compared to the truck’s 

main engine idling fuel consumption rate of one gallon or more per hour for trucks 

(Lambert et al., 2001; Lim, 2002). Drawbacks to diesel APSs are their initial cost, 

additional weight, and maintenance requirements. The cost for an APS ranges from 

$5,000 to $8,000 (U.S. EPA, 2005). Opponents of this approach argue that the added 

weight of an APS reduces the capacity of the truck to carry a full load, resulting in the 

potential loss of revenue. The APS typically weighs 250 to 400 pounds, which is less 

than 0.5 percent of the 80,000 pounds a fully laden truck can weigh, so this impact is 

minor. APSs can have shorter maintenance intervals than the main engine, requiring 

the operator to modify its periodic maintenance schedules to include APS maintenance. 

Some engine manufacturers such as Cummins and Caterpillar are currently developing 

integrated main engine/APS systems that they expect to offer as factory options in 

2006. Such systems are expected to significantly minimize the perceived APS 

drawbacks associated with the high initial cost, shorter maintenance intervals, and the 

added weight. 

Currently, internal combustion engine APSs provide significant NOx emission 

reductions, ranging from 89 to 94 percent less than NOx emissions generated when the 
 29

truck’s main engine is idling and the air conditioning system is engaged (Lim, 2002). 

Other criteria pollutants such as CO and ROG are also reduced. PM emissions may be 

greater or less than the main engine depending on the model year of the truck engine 

on which the APS is installed. That is, if the APS is installed on pre-2007 model truck 

engine, PM emissions are usually lower or, at worst, are the same as main engine idle 

emissions. However, diesel-fueled APSs installed on 2007 and subsequent model year 

PM trap-equipped truck engines are expected to produce higher PM emissions than the 

main engine. Therefore, staff is proposing additional diesel-fueled APS PM emission 

requirements for those APS engines installed on trucks with 2007 and subsequent 

model year diesel engines. 

Staff’s proposed PM emission reduction requirement could be met by retrofitting the 

APS with a level 3 verified particulate trap. The trap may require an active regeneration 

scheme, since the APS exhaust temperature may not be high enough for passive 

regeneration to occur. Based on verbal communication with a manufacturer developing 

PM traps for diesel engines less than 25 hp, it is likely that PM traps for APSs could be 

used to achieve the level 3 verification requirements with modifications. The 

modifications would require the design of an active system that would increase the 

exhaust temperature periodically to reduce the captured PM emissions. These PM trap 

systems are currently designed for applications in generator sets and transportation 

refrigeration units, but can readily be adapted for diesel-fueled APSs since they use the 

same engines and also operate in a similar way as generator sets. 

Integration of main engine/APS exhaust systems and passing the APS exhaust through 

the trap of the main engine may also be used to control PM emissions from the APS. 

Because of warranty issues, staff believes integration of main engine/APS exhaust 

systems to occur at the engine or vehicle manufacturer level rather than by aftermarket 

APS manufacturers. The cost of retrofitting an APS with a diesel-particulate trap is 

estimated to be approximately $1,200 to $1,500 (Lambe, 2005). However, staff’s 

analysis assumes a conservative incremental cost of $2,000 to comply with the 

additional PM requirements. With the current average diesel fuel prices of 

approximately $2.40 per gallon13, the payback period is estimated to be 1.5 to 2.5 years 

for a truck that idles approximately 2,100 hours per year. 

2. Fuel-Fired Heaters 

Fuel-fired heaters are used to provide heat to the cab/sleeper berth and/or to preheat 

the engine block for easy engine start-up during cold weather. Different models exist for 

a variety of applications, such as pick-up trucks, buses, and marine vessels. They can 

operate 20 or more hours on a gallon of diesel fuel, and typically use the fuel from the 

truck’s fuel tank. They are relatively small, inexpensive, and consume much less fuel 

than an idling truck engine. A report by the U.S. EPA estimates that compared to the 

truck’s main engine, diesel fuel-fired heaters reduce NOx emissions by approximately 

99 percent and fuel consumption (and CO2 emissions) by 50 to 80 percent (U.S. EPA, 

 

13 Average weekly on-highway diesel price for the weeks from January 1 to August 1, 2005. 

(http://tonto.eia.doe.gov/oog/info/wohdp/diesel.asp) 
 30

2002). The only drawback of this technology is its inability to provide cooling. Costs of 

fuel-fired heaters range from $1,000 to $3,000 per unit (U.S. EPA, 2005). 

For applications in light-duty and medium-duty vehicle classes, fuel-fired heaters must 

meet the Ultra Low Emission Vehicle (ULEV) standards found in the LEV II regulations 

(13 CCR 1961(a)(15) and (d)). Staff’s proposed requirement that fuel-fired heaters 

meet the ULEV standards in sleeper trucks can be met with existing, commercially 

available, fuel-fired heaters, since many models used for sleeper truck applications are 

currently meeting the ULEV standards. For example, all of Espar’s and Webasto’s fuelfired heaters currently meet the ULEV standards. 

3. Battery Electric and Fuel cell APS 

Battery electric APSs provide cooling and heating for sleeper berth climate control 

without the need to idle the main engine or operate a diesel powered APS. Such 

systems include an independent electrically driven heating and air-conditioning system 

and an inverter to provide 120 Volt AC electrical power for on-board accessories. They 

are capable of providing more than ten hours of continuous cab comfort between 

charges. Depending on the number of batteries installed and alternator capacity, such 

systems typically require two to six hours of charging time. Fuel consumption and 

emissions from the truck engine will increase slightly when the batteries are being 

charged during engine operation. However, the overall emissions from the truck will be 

reduced by eliminating the need to idle the truck engine during layover hours. The cost 

of the commercially available battery systems ranges between $4,000 to $10,000 per 

unit, the higher amount corresponding to a system with an advanced battery system 

(higher capacity and longer life), higher capacity heating and air conditioning system, 

and an inverter charger. Staff estimates that this system would pay for itself in 1 to 2.5 

years. Examples of commercially available battery electric APS systems include Idling 

Solutions’ Idling Solutions 9000 and Bergstrom’s Nite System. 

An auxiliary power source that appears to offer a promising possibility of eliminating 

truck idling emissions is the fuel cell APS. A fuel cell produces electricity by converting 

the chemical energy of fuel directly to electrical power in a controlled chemical reaction. 

Fuel cells are clean and efficient. They can provide sufficient power to heat or cool a 

cab/sleeper compartment and run on-board electrical equipment. However, technical 

and economic issues, such as availability and infrastructure of a suitable fuel, the 

production costs of the units, and integration of the units with other on-board truck 

systems need to be resolved before such systems can become cost-effective for 

commercial truck operators. 

4. Thermal Energy Storage 

Cold storage systems utilize the truck’s air conditioning system to store cooling energy 

when the truck is operated which is later used to cool the sleeper berth when the truck 

is stopped and the driver is resting. Some aftermarket systems are currently, 

commercially available. These systems may be used in conjunction with a fuel-fired 
 31

heater to provide both heating and cooling. As with battery electric APSs, these 

systems must routinely be recharged (approximately 4 to 6 hours of truck operation is 

required). Also, fuel consumption will increase slightly due to the need to operate the 

air conditioning system compressor continuously. However, staff believes that the fuel 

savings from reducing idling of the main engine will offset this potential drawback. An 

example of a cold storage system that is currently commercially available is Webasto’s 

BlueCool Truck system. The system costs, including installation, $3,600 per unit, or 

$4,600 if it includes a heater. 

ii. On-Shore Electrical Power 

The development of an electrical power infrastructure at truck stops and other locations 

is another option to reduce engine idling emissions. On-shore electrical power involves 

the electrification of truck parking spaces to provide power for heating, cooling and onboard accessories. It provides significant emissions benefits at the truck stop area or 

the site where it is installed. However, it is not available everywhere and may take 

many years before the system becomes widely available at truck stops. Even if such 

systems become widely available in the future, truck operators located away from such 

installations may still need an alternative cab comfort technology that is portable with 

the truck. There are currently two methods of using on-shore electrical power today. 

One method allows the truck to “plug-in” to the electrical power grid to power on-board 

air conditioning and heating systems, referred to as “on-board power infrastructure.” 

The other method relies on heating and air conditioning provided at the location where 

the infrastructure is installed, referred to as “off-board power infrastructure.” 

1. On-Board Power Infrastructure 

This technology provides trucks with 110-volt AC electrical power at truck stops, or 

other locations, to run the air conditioning, heating and on-board accessories. This 

requires truck stops to be equipped with electrical outlets throughout the parking spaces 

and trucks need to be equipped or retrofitted with inverter/chargers, electrical power 

connections and electrically driven heating and air conditioning units. The 

inverter/chargers are used to charge the truck batteries from grid supplied electricity and 

to convert the truck batteries' 12-volt DC to 120-volt AC power for all on-board 

accessories. The drawbacks of this system include the high initial infrastructure cost, 

cost for equipment add-ons to trucks, and its availability, which is limited to where the 

infrastructure is installed. The aftermarket cost for add-on parts and installation 

including inverter/chargers, electrical air conditioning system, wiring, outlets, circuit 

breakers, etc., is approximately $4,000 per truck (Perrot et al., 2004). Power 

infrastructure installation cost is approximately $3,500 to $6,000 per truck parking space 

depending on number of pedestals installed (Perrot et al., 2004). The payback period 

for the truck owner is estimated at about 1.5 years (Perrot et al., 2004)14

. 

 

14 The payback period was estimated assuming a diesel fuel cost of $1.50 per gallon and idling 1800 hours per year. 

With the current higher diesel fuel prices ($2.40 per gallon, California average for the weeks from January 1 to 

August 1, 2005) the payback period would be much shorter than the period estimated by Perrot. 
 32

2. Off-Board Power Infrastructure 

An alternative to the on-board power infrastructure has been recently introduced by 

IdleAire Technologies. This system provides 110-volt AC electrical power for on-board 

accessories, an externally installed heating and air conditioning unit and hook-ups for 

basic telephone, internet and television (access to cable/satellite) services at each truck 

parking space. The unit is connected to the truck through a console installed to the 

truck window using a template insert. The console contains all the necessary 

connections and controls, including a card reader for the billing system. Currently, the 

basic services cost about $1.25 to $1.50 per hour. The drawbacks are the high 

infrastructure installation and maintenance costs and its availability limited to where the 

infrastructure is installed. The off-board power infrastructure installation cost is 

approximately $12,000 to $ 20,000 per parking space depending on the number of 

parking spaces installed (Antares, 2005). The advantage of this type of infrastructure is 

that the truck does not need to be modified with any alternative cab comfort technology, 

resulting in immediate benefits to the truck owner using the service through reduced fuel 

consumption and maintenance savings. 
 33

VI. REGULATORY ALTERNATIVES 

Staff evaluated several alternatives to the proposed requirements. The first alternative 

considered was taking no action and solely relying on ARB’s existing anti-idling 

regulatory programs and on voluntary compliance. The second alternative considered 

was requiring engine/vehicle manufacturers to either certify their engines to a low NOx 

idling emission standard or to install a compliant APS system on every sleeper truck 

sold in California. The third alternative considered was staff’s current proposal except 

that the available heating and cooling options for sleeper trucks would be limited to zero 

emission alternative technologies such as battery electric APSs, fuel cells or truck stop 

electrification. A description of the alternatives and the rationale for rejecting them are 

as follows: 

A. NO ACTION 

This alternative would rely on educational and incentive programs to encourage sleeper 

truck owners and operators to voluntarily reduce idling and use cab comfort devices. It 

would not require engine shutdown systems on new trucks nor mandate the five-minute 

idle time limit on sleeper trucks. 

Educational programs would require considerable on-going state resources, and the 

effectiveness of reducing idle emissions is unknown. ARB’s Carl Moyer Program has 

offered incentives to reduce emissions from truck idling by encouraging the purchase 

and installation of cab comfort devices. It offers funds to cover APS installation costs of 

up to $1,600 per diesel-fueled APS installation and up to $3,100 per alternative fuel, 

electric motor, or fuel cell APS installation. To date no applications have been received 

for this incentive program. Although the cost of currently available cab comfort devices 

can be recovered within 1 to 2.5 years from fuel savings and reduced maintenance 

requirements, trucking businesses have not been motivated to use these technologies. 

Hence, the emission reductions expected from voluntary programs that target truck 

idling have not been realized. Staff therefore believes that reducing truck idling only 

through voluntary programs will not be sufficient to achieve ARB’s emission reduction 

goals. 

B. IN LIEU OF ENGINE SHUTDOWN SYSTEMS, REQUIRE ENGINE 

MANUFACTURERS TO CERTIFY ENGINES THAT MEET THE LOW IDLE 

EMISSION STANDARD OR BE EQUIPPED WITH A COMPLIANT APS. 

INCLUDE THE PROPOSED AMENDMENTS TO THE IN-USE IDLING ATCM 

AFFECTING SLEEPER TRUCKS 

This alternative provides only two options for compliance. Beginning with 2008 model 

year diesel engines, an engine manufacturer would be required to either certify its main 

engine to the low NOx idling emission standard or to install an APS on all sleeper trucks 

sold in California. As in the proposed requirements, the engine’s NOx idling emission 

standard would be comparable to that of a diesel-fueled APS. If the engine or vehicle 
 34

manufacturer instead chooses to install an APS, the APS would meet additional PM 

reduction requirements if it were a diesel-fueled APS. 

This alternative would also amend the in-use ATCM, consistent with staff’s proposal, to 

include all sleeper trucks beginning in 2008. Thus, California and out-of-state trucks 

resting during layover hours in California would need to purchase alternative cab 

comfort devices that meet all the emission performance requirements for their 

applicable model year and/or technology selected (see section IV.C. and D. above). 

Staff did not pursue this alternative primarily because of how it would impact buyers of 

California certified trucks. Specifically, although this alternative would require all trucks 

resting during layover hours in California to control idling emissions, it presumes that all 

California certified sleeper trucks undergo and need extended idling operation in 

California. This may not be the case; some California trucking companies only idle for 

extended periods outside of California, or if they do need heating and/or cooling in 

California for extended rest periods, their drivers may either sleep in a hotel or they rely 

on available off-board power infrastructure for their needs. Thus, this alternative would 

force California truck buyers to pay a higher price for a new or used (i.e., 2008 and 

subsequent model year) truck equipped with cab comfort systems they may never need 

or use, resulting in their inability to recover their initial cost which would put them in an 

economic disadvantage with businesses operating out-of-state. 

C. REQUIRE ENGINE SHUTDOWN SYSTEMS AND ONLY ZERO-EMITTING 

ALTERNATIVE TECHNOLOGIES. INCLUDE THE PROPOSED 

AMENDMENTS TO THE IN-USE IDLING ATCM AFFECTING SLEEPER 

TRUCKS 

Similar to staff’s proposal, this alternative would require 2008 and subsequent model 

year trucks to be equipped with engine shutdown systems that would shut down the 

engine after five minutes. It would also require, consistent with staff’s proposal, that all 

sleeper trucks control idling emissions beginning in 2008 (see the previous alternative 

B). This alternative would allow the option of using alternative cab comfort devices but, 

unlike staff’s proposal, it would only allow zero emitting technologies such as battery 

electric APSs, fuel cell APSs, thermal storage systems, truck stop electrification, or any 

other zero emitting technology. In other words, it would not allow manufacturers to 

certify their engines to an optional NOx idling standard or use cab comfort devices such 

as diesel or gasoline powered APSs, fuel-fired heaters or any other on-board device 

that produces emissions during its operation. Staff considered this alternative but does 

not recommend it for the following reasons: 

• Truck stop electrification is currently not available everywhere and would take 

beyond the 2008 timeframe before it is widely available. Thus, truck operator 

needs could not be met at every location and would require other alternatives. 

• Battery electric APS technology would likely be the only available near-term 

technology that could provide for all the truck operator heating and cooling 

needs as long as the truck is in operation long enough to recharge the system 
 35

after layover periods (typically up to 6 hours of operation is needed to fully 

charge the APS). However, this technology has only just recently been 

introduced commercially and acceptance by the industry will be limited until 

enough units have been placed into service and the technology is proven to be 

a durable and cost-effective solution. Several fleets are currently evaluating 

this technology with promising results. 

• Fuel cell APSs are a promising technology but are still in the development and 

demonstration phase and may not be commercially available or cost-effective 

until after 2010. 

Staff believes that most of these alternatives are viable options to comply with staff’s 

regulatory proposal, but availability and commercial acceptance may be limited within 

the time period of the current proposal. However, as these technologies mature, 

production volumes increase, and more experience is gained, they will likely be widely 

used in the future. Thus, while they are certainly viable options, they should not, for the 

reason cited above, be the only options made available to truck operators. 

D. PURSUE REQUIREMENTS THAT ONLY TARGET NEW TRUCKS STARTING 

IN 2008 (DO NOT PROPOSE REQUIREMENTS THAT WOULD IMPACT THE 

EXISTING IN-USE FLEET) 

This alternative would only impact California certified trucks beginning in 2008. 

California trucks would be equipped with either the proposed engine shutdown system 

or the engine would meet an optional NOx idling emission standard. Also, this 

alternative would not modify the current in-use ATCM to include sleeper trucks. 

Under this alternative, owners of 2008 sleeper trucks with engines meeting the NOx 

idling standard, pre-2008 California sleeper trucks, and federal sleeper trucks would be 

allowed to idle their engines during layover hours. Owners of 2008 California sleeper 

trucks equipped with an engine shutdown system would be the only ones that may need 

to purchase cab comfort devices, regardless of whether they idle their trucks in 

California or in other states. 

This alternative would be effective in controlling idle emissions from California sleeper 

trucks beginning with the 2008 model year. However, because it can take as long as 30 

years before the fleet is fully turned over, the near-term emission benefits would be 

small. Also, this alternative would not address idling from existing California and out-ofstate sleeper trucks. In 2010, the existing pre-2008 model year California sleeper trucks 

will contribute 30 percent to the total sleeper truck idling emissions in California, while 

out-of-state sleeper trucks will contribute 63 percent. The remaining 7 percent would be 

due to idling of new 2008 and subsequent model year California registered sleeper 

trucks. Therefore, because the idling emissions from existing California and out-of-state 

sleepers are significant, and controlling these emissions is both feasible and costeffective, staff rejected this alternative. 
 36

VII. ECONOMIC IMPACTS 

A. LEGAL REQUIREMENTS 

Government Code Sections 11346.3 and 11346.5(a) require state agencies adopting or 

amending any administrative regulations to identify and assess the potential for adverse 

economic impacts on California businesses and individuals. The assessment must 

include a consideration of the impact of the proposed regulation on California jobs, 

business expansion, elimination or creation of business, and the ability of California 

businesses to compete with those of other states. State agencies are also required to 

estimate the cost or savings to any state or local agency, and school districts. The 

estimate must include any non-discretionary cost or savings to local agencies and the 

cost or savings in federal funding to the state. 

B. AFFECTED BUSINESSES 

Businesses that may be affected by the proposed regulation include heavy-duty engine 

and vehicle manufacturers, manufacturers of alternative idle reduction devices and 

trucking businesses. Based on certification data, ARB has identified 21 heavy-duty 

engine manufacturers worldwide that manufacture and certify their engines for sale in 

California. Approximately eight heavy-duty vehicle manufacturers manufacture and sell 

heavy-duty vehicles in California. However, none of the heavy-duty engine or vehicle 

manufacturing businesses is located in California, and none is considered to be small 

business. 

The exact number of manufacturers of idle reduction devices is unknown. However, 

staff estimates that there are at least 21 manufacturers that produce internal 

combustion APSs, fuel-fired heaters, truck stop electrification, battery electric APSs, 

inverter chargers, etc.15 Approximately 48 percent of these manufacturers produce 

diesel-fueled APSs and the remaining 52 percent produce other cab comfort devices 

such as fuel-fired heaters, truck stop electrification, battery electric APSs, etc. Some of 

the APS manufacturers are part of bigger companies that design and manufacture 

specialty engineered products for the automotive, marine, industrial, medical and 

aerospace industries. Such APS manufacturers are not considered small businesses. 

Staff estimates that about 70% of the internal combustion APS manufacturers are small 

businesses. However, none of these manufacturers are based in California. 

The number of California trucking businesses affected by the proposal was estimated 

from California Highway Patrol’s Biennial Inspection of Terminals 16 Program database. 

Approximately 98 percent of California trucking businesses have fleet sizes of 24 trucks 

 

15 The number of idle reduction technology manufacturers is determined from a listing of idle reduction technologies 

at the U.S. EPA website (http://www.epa.gov/otaq/smartway/idlingtechnologies.htm) and from a listing at 

http://www.truckinginfo.com . 

16 California Vehicle Code Section 34501.12 requires any person or organization directing the operation of trucks or 

trailers to participate in an inspection program conducted by the California Highway Patrol to inspect California 

truck terminals every two years. 
 37

or less. Assuming the fleet size of a small business to consist of 24 trucks or less, 

approximately 98 percent of the California trucking businesses are in the small business 

category. 

The number of out-of-state based trucking businesses that operate in California is 

difficult to determine. However, staff analyzed the 2002 Vehicle Inventory and Use 

Survey database (U.S. Census Bureau, 2005) to get a rough estimate of the fleet 

composition of the 49-states. Based on this analysis, staff assumes that the out-of-state 

fleet mix is representative of those trucks operating in California. Similar to California 

trucking businesses, 99 percent of out-of-state businesses have fleet sizes of 20 trucks 

or less, and thus could be considered small businesses17. 

C. POTENTIAL COSTS TO ENGINE MANUFACTURERS 

The proposal would require engine manufacturers to install a non-programmable and 

tamper-proof engine shutdown system on new 2008 and subsequent model year 

California heavy-duty engines. As previously discussed, an engine shutdown system is 

a standard feature on current electronically controlled on-road diesel engines, but are 

presently not programmed to shut the engine down after five minutes of idling. Setting 

the idle time is left to the truck owner, and the system can easily be overridden to allow 

the engine to idle continuously. Staff therefore, expects engine manufacturers to 

comply with this requirement through a minor change in the programming of the 

electronic engine software. As a result, staff expects that engine manufacturers will not 

incur any significant additional cost in developing the engine shutdown technology to 

comply with the proposed requirement, as no additional hardware costs should be 

needed. 

In addition, engine manufacturers that certify engines meeting the proposed optional 

NOx idling emission standard or install a California compliant APS system may incur 

additional cost due to the proposed vehicle labeling requirements. However, staff 

believes this incremental cost to be negligible and absorbable within the purchase price 

of the main engine or the APS system, whichever is applicable. 

Since the proposed new engine requirement is a California only requirement, it is 

projected to have a minimal cost impact on engine manufacturers. This cost is due to 

additional administrative costs related to the need to separately manufacture and track 

those engines destined for sale in California from those for sale in the other 49-states. 

However, these costs may be further reduced should engine manufacturers elect to also 

incorporate engine shut down systems in engines destined for sale in the other 49-

states. Staff has assumed a minimal price increase of $100 per engine to cover the 

additional administrative costs and the minimal reprogramming costs. 

 

17 The reason for using fleet size of 20 trucks or less as a cut point for the 49-state fleet analysis as opposed to 24 

trucks or less for the California fleet is because the 2002 Vehicle Inventory and Use Survey database bins fleet sizes 

as 1 to 5, 6 to 10, 11 to 20, 21 to 50, etc., and therefore, it was not possible to use 24 trucks as a cut-point for the 49-

state analysis. 
 38

D. POTENTIAL COSTS TO TRUCK MANUFACTURERS 

The proposed regulation is not expected to result in any significant increase in costs to 

truck manufacturers. Engine shutdown software is already present and integrated with 

the truck. Staff anticipates that current truck manufacturing practices will not be 

significantly affected by the proposed regulation. Manufacturers will continue to 

manufacture trucks according to their own or customer specifications. Staff’s proposal 

may also create a demand for “factory installed” cab comfort devices but offering them 

would be a business decision that would also benefit the manufacturer. However, since 

the proposed regulation is a California only requirement, they may incur a minimal 

increase in administrative costs in assuring that the engines installed on the trucks meet 

the proposed requirements. The proposed vehicle labeling requirements may also add 

to the cost of the truck, in instances where the truck manufacturer is responsible for 

producing and affixing the label to the outside of the truck. Staff assumes these 

incremental costs are negligible and absorbable within current truck pricing since truck 

manufacturers already have to track engines, transmissions, and other customer order 

components in vehicle orders. 

E. POTENTIAL COST TO DIESEL-FUELED APS MANUFACTURERS 

The proposed regulation allows the use of any alternative technology provided that the 

APS complies with applicable California emission standards and test procedures for 

their fuel and horsepower category. However, the proposal requires diesel-fueled APSs 

produced for applications with 2007 and subsequent model year diesel engines to meet 

additional PM controls. Manufacturers of diesel-fueled APSs that comply with additional 

PM controls may incur an additional cost in developing a PM trap with an active 

regeneration scheme capable of reducing PM emissions by 85% from the off-road Tier 

4 standards. Furthermore, trucks equipped with PM trap-equipped APSs would need a 

label affixed to the outside of the truck. According to one diesel PM trap manufacturer, 

the cost of retrofitting a diesel-fueled APS with an active PM trap is estimated to be 

$1,200 to $1,500 (Lambe, 2005). However, staff assumed a conservative incremental 

cost of $2,000 to comply with the additional PM control, including the cost of verifying 

the APS with a PM trap and creating a label. 

F. POTENTIAL IMPACT ON TRUCKING BUSINESSES 

The proposed requirements will affect both California and out-of-state trucking 

businesses that already own sleeper trucks and those that will purchase new ones in 

2008. Although not required by the proposal, for purposes of this analysis, staff 

assumes that all trucking businesses will incur additional costs in purchasing alternative 

cab comfort technologies to provide for sleeper berth comfort and electrical power for 

accessories. Assuming businesses will use the most commonly used alternative today, 

the diesel-fueled APS, staff expects that businesses that own pre-2007 model year 

sleeper trucks will incur a cost of approximately $5,000 to $8,000, while businesses that 

purchase new 2007 and subsequent model year sleeper trucks will incur a cost of 

approximately $7,000 to 10,100 (cost of an APS with additional PM control and, for 
 39

California certified trucks, an engine shutdown system for 2008 and subsequent model 

year engines). These costs are based on purchasing an aftermarket diesel-fueled APS, 

which is expected to cost more than an APS offered by the vehicle manufacturer as a 

factory option. 

While existing California and out-of-state trucking businesses will certainly be impacted 

by the proposed regulations, the impact will depend on how often their trucks require 

extended stays in California. For example, if extended stays for an owner/operator or a 

truck fleet rarely happen in California, a business decision would need to be made 

whether to equip its truck(s) with an alternative cab comfort device. This decision would 

be based on how soon they could recover this additional incurred cost. Depending on 

the amount of idling hours reduced and the type of alternative cab comfort technology 

used, these additional costs can be recovered within 1 to 2.5 years through reduced fuel 

consumption and maintenance requirements. Therefore, overall, the proposed 

requirements will benefit the truck owner because they will realize a net savings from 

improved operating costs. An example of how these savings will be achieved is shown 

below, in Table 2. 

Table 2 shows the savings realized and the payback periods for a diesel-fueled APS. 

The savings were estimated assuming that a sleeper truck idling consumes one gallon 

per hour and idling is reduced by six hours per day. The cost of diesel fuel was 

estimated at $2.40 per gallon18. The Technology and Maintenance Council’s 

Recommended Practice 1108 (RP 1108) provides a method for estimating preventive 

maintenance and engine overhaul costs due to long duration idling. Using RP 1108, 

reducing idling by one hour results in preventive maintenance savings of $0.07 per 

hour, and engine overhaul savings of $0.16 per hour. It should be noted that the 

maintenance savings shown in Table 2 account for the additional costs that would be 

incurred by the maintenance requirements of the diesel-fueled APS19. 

 

18 The diesel fuel cost of $2.40 per gallon is obtained by averaging the weekly California diesel fuel prices for the 

weeks from January 1 to August 1, 2005. Historic weekly retail on-highway diesel prices are available from the 

U.S. DOE, Energy Information Administration at http://tonto.eia.doe.gov/oog/info/wohdp/diesel.asp. 

19 The APS maintenance cost is based on the AXP 1000 maintenance requirements of $420. AXP 1000 is a dieselfueled APS manufactured and sold by Engine and Energy Technology Corporation (http://www.eent.net/). 
 40

Table 2: Net Fuel and Maintenance Savings 

Vehicle Fuel Savings 

(gallons/year) 

Fuel Cost 

Savings 

$/year

Maintenance 

Savings 

$/year 

Total 

Savings 

$/year 

 

Truck with a 

sleeper berth using 

a diesel-fueled APS

1750 $ 4,200 $ 77 $ 4,280 

Cost of APS Payback Period 

APS without PM aftertreatment - $ 5,000 ~ 1.2 years

APS with PM aftertreatment + idle shutdown system - $10,100 ≤ 2.5 years 

G. POTENTIAL IMPACT ON BUSINESS COMPETITIVENESS 

The proposed regulation is not expected to adversely impact the ability of California 

businesses to compete with businesses in other states. As previously discussed, 

although businesses owning or purchasing new trucks with sleeper berths will most 

likely require that they be equipped with an alternative cab comfort technology, resulting 

in higher initial purchase costs, those businesses will also realize net savings in 

operating costs for those trucks. Staff’s proposal is expected to improve, over the 

useful life of the truck, California trucking businesses’ competitiveness (compared to 

trucking businesses that do not have alternative cab comfort technology on their trucks) 

by significantly reducing operating costs. Also, out-of-state trucking businesses that 

operate in California and install alternative cab comfort technology will also benefit from 

the same competitiveness advantage. 

H. POTENTIAL IMPACT ON JOBS AND BUSINESS CREATION, ELIMINATION, 

OR EXPANSION 

The proposed regulation is not expected to have a significant effect on the creation, 

elimination or expansion of jobs and businesses in California. However, the regulation 

may result in an increase in demand for cab comfort devices, and this in turn may result 

in the creation or expansion of some businesses. The increased demand for alternative 

cab comfort technologies may also result in the creation of new jobs related to research 

and development to further improve these technologies, and jobs related to the 

manufacturing, distribution and marketing of these technologies. Most of the 

businesses and jobs created are expected to be located near the engine and/or vehicle 

manufacturing facilities outside of California but some may be created in California. 
 41

I. POTENTIAL COSTS TO LOCAL AND STATE AGENCIES 

There are no additional net costs for local and state agencies associated with adopting 

the proposed regulation. Typically, local government and state agencies purchase 

trucks without sleeper berths, so those trucks only require minimal modifications to the 

engine’s software, resulting in minimal cost to the purchaser. It is expected that 

agencies purchasing compliant trucks would realize net operating savings from reduced 

fuel consumption due to the engine shutdown technology. Other costs, such as 

implementation costs to the state as a result of this rulemaking, would be costs directed 

to the ARB to implement and enforce the requirements, which should be absorbable 

within the existing ARB programs and budget. 
 42

VIII. ENVIRONMENTAL JUSTICE 

The ARB is committed to integrating environmental justice into all of its activities. State 

law defines environmental justice as the fair treatment of people of all races, cultures, 

and incomes with respect to the development, adoption, implementation, and 

enforcement of environmental laws, regulations, and policies. On December 31, 2001, 

the Board approved “Policies and Actions for Environmental Justice”, which formally 

established a framework for incorporating environmental justice into the ARB's 

programs consistent with the directives of state law. The policies developed apply to all 

communities in California, but recognize that environmental justice issues have been 

raised more in the context of low income and minority communities. 

These Policies are intended to promote the fair treatment of all Californians and cover 

the full spectrum of ARB activities. Underlying these Policies is a recognition that the 

ARB needs to engage community members in a meaningful way as it carries out its 

activities. People should have the best possible information about the air they breathe 

and what is being done to reduce unhealthy air pollution in their communities. The ARB 

recognizes its obligation to work closely with all stakeholders--communities, 

environmental and public health organizations, industry, business owners, other 

agencies, and all other interested parties to successfully implement these Policies 

(ARB, 2001c). 

The proposed truck idling emission reduction requirements would benefit the people of 

California by reducing their exposure to harmful pollutants and diesel toxics. In 

particular, the proposed requirements will provide significant air quality benefits to 

communities located in proximity to truck stops, ports, distribution centers, and other 

truck idling centers where a high density of trucks idle together for extended periods of 

time. Furthermore, most of these locations are low-income areas that are already 

affected by the cumulative impact of air pollution from multiple mobile, commercial, 

industrial, areawide, and other sources. The adoption of this regulation, therefore, 

affirms the Board’s commitment to the fair treatment of all people throughout California. 

 
 43

IX. ENVIRONMENTAL IMPACTS AND COST-EFFECTIVENESS 

This chapter presents the air quality benefits and cost-effectiveness resulting from the 

implementation of the proposed idle reduction requirements. 

A. AIR QUALITY BENEFITS 

The proposed regulations achieve emission reductions by reducing the idling operations 

of diesel engines and trucks through the use of existing, cost-effective technologies. 

For various reasons, it is difficult to precisely estimate the emission benefits of the 

proposed regulations because staff can not accurately predict at this time the type and 

distribution of alternative technologies used to comply with the proposed regulation. 

Another major uncertainty is the idling emission rate estimates associated with 

aftertreatment-based NOx and PM control technologies to be used with the 2007 and 

later model year diesel engines. Staff is not aware of any data that describe the 

performance of trap-based technologies or NOx catalysts during extended diesel idling 

operation. However, based on staff’s understanding of how these technologies work, 

the following assumptions have been made for estimating the baseline emissions of 

2007 and later model year diesel engines: 

1. PM traps by nature of their construction are expected to trap PM at the same 

efficiency during idling as when the truck is operating under other typical driving 

conditions. Thus, the 2007 and later model year PM idling emission rates reflect 

the use of highly efficient PM traps. 

2. NOx catalysts require a minimum temperature (light-off temperature) before the 

catalytic reactions needed to reduce NOx occur. The light-off temperature for 

NOx catalysts is generally above 200°C (MECA, 2000), while exhaust 

temperatures during extended idling are typically below 150°C (Hallstrom, 2005). 

Thus, for purposes of estimating NOx catalyst effectiveness during extended 

idling, engine-out NOx emissions are assumed to be unaffected by NOx 

catalysts, unless the engine is idling immediately following over-the-road 

operation (explained below). 

The U.S. EPA, in laboratory testing to demonstrate the technical feasibility of the 

2007 heavy-duty engine standards, observed NOx emission control for more 

than 10 minutes of idle operation following loaded (or high temperature) 

conditions due to the thermal inertia of the NOx catalyst (U.S. EPA, 2000). 

However, the size of the NOx catalyst system relative to the engine size tested 

was significantly larger than what is currently being developed for diesel engines. 

A smaller catalyst system would have less thermal inertia, which would 

correspondingly result in controlling NOx emissions for a shorter period of time 

than the 10 minutes observed in the U.S. EPA testing. Thus, due to limited data 

on NOx catalysts currently being developed, staff assumes that NOx control 

during idling resulting from the thermal inertia mass of the NOx catalysts will be 
 44

less than five minutes following over-the-road operation. Thus, NOx emission 

reduction estimates from the proposed requirements will remain unaffected, as 

the first five minutes of idling operation have not been included in staff’s emission 

benefit estimates for this proposal. 

Idle emission rates incorporated in California’s emissions inventory model, EMFAC2002 

ver 2.2 (ARB 2003), are based on test data from a limited number of trucks. In addition, 

the emission test data were obtained at “curb” idle speeds and did not include 

accessory loading. However, studies have shown that idling emissions are greatly 

dependent on ambient conditions, accessory loading, and engine speed (Lambert et al., 

2001; Storey et al., 2003). As a result, staff modified the EMFAC2002 idle emission 

factors using emissions test data obtained from phase 1 of the Coordinating Research 

Council (CRC) project E-55/E-59 (Gautam et al., 2003) and emissions test data from a 

multi-agency study which included the U.S. EPA and Oak Ridge National Laboratory 

(ORNL) (Storey et al., 2003). The idle emission rates used in quantifying the air quality 

benefits from the proposed regulation are shown in Table 3. 

Table 3: Fleet Average Idle Emission Factors 

Weighted Average Idle Emission factors 

Calendar

Year 

Model 

Year 

NOx 

(grams/hour)

ROG 

(grams/hour)

PM 

(grams/hour)

CO2

(grams/hour)

Pre-1991 39.8 20.2 5.3 6228 

2010 1991-2006 115.3 9.4 1.9 6228 

2007-10 115.3 8.3 0.16 6228 

Pre-1991 39.8 20.1 5.2 6228 

2020 1991-2006 115.3 8.9 1.8 6228 

2007-20 115.3 8.3 0.16 6228 

As shown, the PM emission rates for pre-2007 and 2007-10 model years differ greatly, 

as one would expect with the use of PM traps beginning in 2007. The NOx and ROG 

emission rates are assumed not to be impacted by a NOx catalyst at idle and thus are 

somewhat comparable for 1991-2006 and 2007-10 model years. The increase in the 

NOx emission rates for 1991 and later versus pre-1991 model years may be attributed 

to the high idling NOx emission rates associated with the post-1990 electronically 

managed engines which are likely to have advanced timing at low loads (or low 

temperatures) to avoid white smoke conditions (Clark et al., 2005). 

Because of the engine shutdown requirements, the proposed regulation affects both 

sleeper and non-sleeper trucks. However, the emission benefits of staff’s proposal 

consider only sleeper trucks. This is because the existing in-use ATCM already 

requires the operator of a non-sleeper truck to shut down his/her engine after five 
 45

minutes of continuous idling, and thus the emission benefits from non-sleeper trucks 

have already been accounted for. Staff’s emission benefit analysis includes both 

California and out-of-state registered sleeper trucks, and assumes that all pre-2007 

sleeper trucks will employ as an alternative to idling, diesel-fueled APSs certified to the 

California off-road or federal non-road standards. 2007 and subsequent model year 

sleeper trucks were assumed to employ diesel-fueled APSs verified to a level 3 or 85% 

PM reduction from the Tier 4 off-road standards shown in Table 4. Furthermore, the 

average power demand for an APS operating under extreme climate conditions is 

estimated to be approximately 2.3 kW for winter conditions and 3.1 kW for summer 

conditions (Wallace, 2003; Lutsey, 2003). Staff assumed that the diesel-fueled APS 

would provide an average of 2.7 kW power to provide sleeper berth comfort and 

electrical power for accessories. Also, 25 percent of all trucks on the road on a typical 

day in California are estimated to be out-of-state registered trucks (ARB, 2003). Staff 

estimates that 90 percent of those out-of-state registered trucks are sleeper trucks that 

idle an average of six hours per day in California. 

Table 4: Off-Road Diesel Emission Standards (g/kW-hr)

Model Year Horsepower 

Category NOx+NMHC CO PM 

hp < 11 

(kW < 8) 7.5 8.0 0.8 2005 – 2008 

(Tier 2) 11 ≤ hp < 25 

(8 ≤ kW < 19) 7.5 6.6 0.8 

hp < 11 

(kW < 8) 7.5 8.0 0.4 2008+ 

(Tier 4) 11 ≤ hp < 25 

(8 ≤ kW < 19) 7.5 6.6 0.4 

In estimating the emission rates of diesel-fueled APSs, staff analyzed the 2005 

emission certification test data of off-road diesel engines used in APSs (engines with 

power ratings between 5 to 19 kW). The gram per hour emission rates were estimated 

from the average of the certification test data (in grams per kW-hour) assuming that the 

APS provides an average power of 2.7 kW. The average of the certification data and 

the gram per hour emission rates are shown in Table 5. The certification test data does 

not include CO2 emissions. Therefore, in calculating the CO2 emission reductions, staff 

used CO2 emission rates from an APS test data report published by U.S. EPA. (Lim, 

2002). 
 46

Table 5: Diesel Fueled APS Emission Rates

Number of 

Engines NMHC+NOx CO PM CO2

Average of Certification 

Test Data 

(grams/kW-hour) 

5.6 2.3 0.32 --- 

APS Emission Rate 

(grams/hour) 

68 

15.120 6.2 0.87 2228 

In addition to reducing emissions of criteria pollutants, the proposed regulation also 

reduces greenhouse gas (GHG) emissions, such as CO2, methane (CH4), and nitrous 

oxide (N2O) emissions. CO2 is by far the most prevalent GHG, and as such the major 

contributor to global warming. A major source of CO2 emissions is human activity and 

in particular fossil fuel burning in the electric generation, industrial, and transportation 

sectors (see Figures 7 and 8) (Bemis, 2005). As discussed in Chapter II, truck idling 

consumes diesel fuel from 0.4 to 1.6 gallons per hour depending on engine speed and 

load. Therefore, reduced idling will result in reduced amount of fuel burned. Since CO2

is the direct product of fuel burning, reducing fuel consumption also reduces CO2 

emissions. 

Concerned about the impact on climate change, the state of California has set a target 

to reduce GHG emissions to 2000 levels by 2010, to 1990 levels by 2020, and to 80% 

below 1990 levels by 2050. The proposed regulation is estimated to reduce CO2

emissions by nearly 1930 tpd (0.7 million tons per year) and 2280 tpd (0.8 million tons 

per year) statewide in 2010 and 2020, respectively. The resulting emission reductions 

for NOx, ROG, PM, and CO2 for calendar years 2010 and 2020 for both statewide and 

the South Coast Air Basin are shown in Tables 6, 7, 8, and 9. The emission reductions 

assume full compliance with the proposed requirements. 

 

20 As discussed in Chapter IV, the proposed 30 gram per hour optional NOx idling emission standard was based on 

the average NOx emission level of 2005 certification test data of off-road diesel engines used in APSs (engine with 

power ratings between 5 to 19 kW). The difference between the 15.1 grams per hour NOx+NMHC emission rate of 

the APS (Table 5) and the 30 gram per hour optional NOx emission standard, discussed in Chapter IV, is a result of 

calculating the optional NOx emission standard based on the assumption that the APS provides the peak power of 5 

kW, while the APS NOx+NMHC emission rate in Table 5 assumes that the APS provides an average power of 2.7 

kW. 
 47

Nitrous Oxide

6.4%

Fossil Fuel 

Combustion 

CO2

81.0%

High GWP 

Gases

3.4%

Methane

6.2%

Non-Fossil 

Fuel CO2

2.8%

Figure 7. California GHG emissions by Type of Gas in 2003 

(Bemis, 2005). 

Agriculture & 

Forestry

8.2%

Industrial

21.4%

Others 

8.5%

Transportation

42.8%

Electric Power

19.0%

Figure 8. Sources of California’s 2003 GHG Emissions (by End-Use Sector) 

(Bemis, 2005). 
 48

Table 6: 2010 Estimated Statewide Idling Emission Benefits 

Sleeper Trucks Only 

 Vehicles NOx ROG PM CO2 

Baseline Emissions (tpd) Calendar Year 2010 

CA Registered 

Sleeper Trucks 30,161 20 2.1 0.39 1200 

Out-of-State 

Sleeper Trucks 45,241 33 2.5 0.34 1800 

Total Baseline 75,402 53 4.6 0.73 3000 

Emission Reductions 

(tpd) Calendar Year 2010 

CA Registered 

Sleeper Trucks 30,161 17 1.9 0.26 770 

Out-of-State 

Sleeper Trucks 45,241 29 2.2 0.16 1160 

Total Reductions 75,402 46 4.2 0.42 1930 

Table 7: 2020 Estimated Statewide Idling Emission Benefits 

Sleeper Trucks Only 

 Vehicles NOx ROG PM CO2 

Baseline Emissions (tpd) Calendar Year 2020 

CA Registered 

Sleeper Trucks 35,652 26 2.0 0.16 1420 

Out-of-State 

Sleeper Trucks 53,478 39 2.8 0.08 2130 

Total Baseline 89,130 65 4.8 0.24 3550 

Emission Reductions 

(tpd) Calendar Year 2020 

CA Registered 

Sleeper Trucks 35,652 22 1.8 0.08 910 

Out-of-State 

Sleeper Trucks 53,478 34 2.6 0.02 1370 

Total Reductions 89,130 56 4.4 0.10 2280 
 49

Table 8: 2010 Estimated South Coast Air Basin Idling Emission Benefits 

Sleeper Trucks Only 

 Vehicles NOx ROG PM CO2 

Baseline Emissions (tpd) Calendar Year 2010 

CA Registered 

Sleeper Trucks 11,631 8 0.8 0.14 460 

Out-of-State 

Sleeper Trucks 17,447 13 0.9 0.12 690 

Total Baseline 29,078 21 1.7 0.26 1150 

Emission Reductions 

(tpd) Calendar Year 2010 

CA Registered 

Sleeper Trucks 11,631 7 0.7 0.09 300 

Out-of-State 

Sleeper Trucks 17,447 11 0.9 0.06 440 

Total Reductions 29,078 18 1.6 0.15 740 

Table 9: 2020 Estimated South Coast Air Basin Idling Emission Benefits 

Sleeper Trucks Only 

 Vehicles NOx ROG PM CO2 

Baseline Emissions (tpd) Calendar Year 2020 

CA Registered 

Sleeper Trucks 13,988 10 0.8 0.06 560 

Out-of-State 

Sleeper Trucks 20,981 15 1.1 0.03 830 

Total Baseline 34,969 26 1.9 0.08 1390 

Emission Reductions 

(tpd) Calendar Year 2020 

CA Registered 

Sleeper Trucks 13,988 9 0.7 0.03 360 

Out-of-State 

Sleeper Trucks 20,981 13 1.0 0.01 520 

Total Reductions 34,969 22 1.7 0.04 880 
 50

B. COST-EFFECTIVENESS 

Staff’s proposal is expected to provide a cost savings to truck owners over the useful life 

of the truck by reducing fuel consumption and truck’s maintenance requirements. For 

example, as previously shown in Table 2, a truck that idles an average of approximately 

six hours per day and uses a diesel-fueled APS as an alternative to main engine idling 

would save approximately $4,300 per year. With such savings, the cost of the APS 

would be recovered within 1 to 2.5 years. Therefore, the cost-effectiveness of the 

proposed rule is in reality zero because it is a cost savings. However, staff estimated 

the cost-effectiveness of the proposal without considering the associated savings in 

order to see how it compares with cost-effectiveness estimates of other regulations 

adopted by the ARB. 

The proposed rule would require new 2008 and subsequent model year California 

certified diesel engines to be equipped with a non-programmable engine shutdown 

system. Pre-2008 trucks would be required to comply with the proposed rule by 

manually turning the engine off. The staff's proposal does not include any retrofit 

requirement for these engines. Therefore, the cost of compliance with the proposed 

requirements should only be the cost incurred to comply with the engine shutdown 

requirements applicable to only 2008 and later diesel engines. However, although it is 

not required by the proposed regulation, staff expects that in practice, operators and 

owners of sleeper trucks of any model year will likely need an alternative cab comfort 

technology as a substitute to main engine idling. Thus, for new 2008 and subsequent 

model year sleeper trucks, the costs of complying with the proposed requirements 

would include costs associated with the engine shutdown system and costs associated 

with the alternative cab comfort technology/strategy used to replace main engine idling. 

For existing pre-2008 model year sleeper trucks and out-of-state trucks that frequently 

operate in California, the costs of complying with the proposed requirements would 

include costs associated with the retrofit of an alternative cab comfort 

technology/strategy used to replace main engine idling. 

It is difficult at this time to assess to what extent each alternative cab comfort 

technology will be used when the proposed regulation takes effect. Staff has therefore 

estimated the cost-effectiveness of the proposed regulation based on the highest cost 

that a truck operator may incur to comply with the proposed regulation. Thus, our costeffectiveness calculation for the proposed regulation assumes that a 2008 and 

subsequent model year California truck would have an engine shutdown system and 

uses, as an alternative to idling, a diesel-fueled APS equipped with a level 3 verified PM 

control strategy. A 2007 model year California truck or a 2007 and later model year outof-state truck is also assumed to use, as an alternative to idling, a diesel fueled APS 

with a level 3 verified PM control strategy. A pre-2007 California or pre-2007 out-ofstate truck is assumed to use a diesel-fueled APS with no aftertreatment. The 

calculation furthermore assumes the cost of a diesel-fueled APS with aftertreatment to 

be $10,000, and that of an engine shutdown system to be $100. The cost of a 

commercially available diesel-fueled APS with no aftertreatment varies from $5,000 to 
 51

$8,000. Thus, staff assumed an average cost of $6,500 for an APS with no 

aftertreatment. The lifetime of the APS is assumed to be 10 years. 

As shown in Table 10, the cost-effectiveness of the proposed regulations is $2.00 per 

pound of NOx plus ROG reduced, for a new 2008 model year California truck; $1.98 per 

pound of NOx plus ROG reduced, for a 2007 model year California truck or a 2007 

model year or newer out-of-state truck; and $1.44 for a pre 2007 California or out-ofstate truck. 

Table 10: Cost-Effectiveness in Dollars per Pound of NOx+ROG Reduced 

Sleeper Trucks 

2008 

CA Only

2007 

CA and Non-CA

Pre 2007 

CA and Non-CA

Fleet Average NOx 115.3 115.3 99.6 

Idle Emission Factor 

(grams/hour) ROG 8.3 8.3 12.2 

Lifetime Truck 

Emissions (10 years) 

(pounds per truck) 

NOx+ROG 5758 5758 5210 

APS Emission Rates 

(grams/hour) NOx+ROG 15.1 15.1 15.1 

Lifetime APS 

Emissions (pounds) NOx+ROG 702 702 702 

Lifetime Emission 

Reduction NOx+ROG 5056 5056 4507 

Cost Of Technology 

APS $10,000 $10,000 $6,500a

Engine Shutdown 100 0 0 

APS + Engine Shutdown $10,100 $10,000 $6,500 

Cost-Effectiveness 

($ per pound of NOx+ROG) $2.00 $1.98 $1.44 

Fleet Distribution CY 2008 4% 7% 89% 

Fleet Average 

Cost-effectiveness 

($ per pound of NOx+ROG) 

1.51 

The fleet average cost-effectiveness is difficult to estimate as it is difficult to predict the 

fraction of the fleet that will install cab comfort devices to substitute for main engine 

idling. In particular, it is more difficult to assess or predict the fraction of out-of-state 

trucks that will install a cab comfort device. Depending on how often out-of-state 

sleeper trucks frequent California and require an extended stay, a business decision on 
 52

the part of the truck fleet or owner/operator would be made whether to have cab comfort 

devices installed. However, for the purposes of this analysis, staff assumed the “worst”, 

that all out-of-state sleepers entering California would have cab comfort devices 

installed. Therefore, staff estimated the fleet average cost-effectiveness assuming that 

all California sleeper trucks and all out-of-state sleeper trucks entering California will be 

retrofitted with a diesel-fueled APS. Based on these assumptions, the fleet average 

cost-effectiveness is estimated to be $1.51 per pound of NOx plus ROG reduced, which 

compares favorably with recently adopted ARB emission reduction regulations. 
 53

X. CONCLUSIONS AND RECOMMENDATION 

The proposed idle reduction requirements are necessary to achieve emission 

reductions needed to meet clean air goals as specified in the 2003 SIP. The proposed 

requirements can be met using existing, commercially available technologies. Such 

technologies would significantly reduce the idling time of sleeper trucks and result in a 

substantial reduction in emissions of NOx, ROG, PM, and CO2. The proposed 

requirements will result in a cost savings to the trucking industry and are therefore 

clearly cost-effective. But for comparative purposes (i.e., without accounting for the 

savings associated with reduced fuel consumption and maintenance costs), the costeffectiveness of the proposed regulation compares favorably with other mobile source 

and fuels regulations adopted by the Board. In addition to reducing greenhouse gas 

emissions, it will also help reduce the state’s dependency on foreign oil and is also 

consistent with the Board’s policy regarding Environmental Justice. The staff therefore 

recommends that the Board adopt the proposed truck idling emission reduction 

requirements for on-road heavy-duty diesel engines/trucks. 
 54

XI. REFERENCES 

Antares (2005). Summary of Operations: Truck Stop Electrification Facilities of the New 

York State Thruway. Antares Group Inc. Final Report prepared for the New York 

State Energy Research and Development Authority. January 2005. 

ARB. (1998a). Proposed Amendments to Heavy-Duty Vehicle Regulations: 2004 

Emission Standards; Averaging, Banking and Trading; Optional Reduced 

Emission Standards; Certification Test Fuel; Labeling; Maintenance Requirements 

and Warranties. Staff Report. Sacramento: March 6, 1998 

ARB. (1998b). Proposed Identification of Particulate Emissions from Diesel-Fueled 

Engines as a Toxic Air Contaminant. Staff Report. Sacramento: June 1998. 

(http://www.arb.ca.gov/regact/diesltac/diesltac.htm) 

ARB. (2001a). Public Hearing to Consider Amendments Adopting More Stringent 

Emission Standards for 2007 and Subsequent Model Year New Heavy-Duty 

Diesel Engines. Staff Report. Sacramento: September 7, 2001. 

 

ARB. (2001b). ARB Fact Sheet: Air Pollution and Health. Accessed July 14, 2005. 

(http://www.arb.ca.gov/research/health/fs/fs1/fs1.htm) 

ARB. (2001c). Policies and Actions for Environmental Justice. 

Sacramento: December 2001. (http://www.arb.ca.gov/ch/programs/ej/ej.htm) 

ARB. (2002b). Global Warming and Greenhouse Gas Emissions from Motor Vehicles. 

Staff Presentation to the Board (AB 1493). Sacramento: September 2002. 

(http://www.climatechange.ca.gov/background/) 

ARB. (2003). On-Road Emissions Inventory Model: EMFAC2002, ver 2.2. 

Release Date: April, 2003. 

(http://www.arb.ca.gov/msei/on-road/latest_version.htm) 

Bemis (2005). E-mail communication. Gerry Bemis. California Energy Commission 

(CEC). Re: Climate Change Pollutants. Pie Charts. August 15, 2005. 

Brodrick, Christie-Joy, Nicholas P. Lutsey, Quentin A. Keen, Daniel I. Rubins, John P. 

Wallace and Harry A. Dwyer, S. William Gouse, III. Truck Idling Trends: Results 

of a Pilot Survey in Northern California. Society of Automotive Engineers, 2001-

01-2828 

Clark, Nigel N., ABM S. Khan, Gregory J. Thompson, W. Scott Wayne, Mridul Gautam, 

and Donald W. Lyons. Idle Emissions from Heavy-Duty Diesel Vehicles. 

2005 Diesel Engine Emissions Reduction (DEER) Conference. 

Chicago, Illinois. August 21-25, 2005.
 55

Gautam, Mridul, Nigel N. Clark, W. Scott Wayne, Gregory Thompson, Donald W. Lyons, 

Wesley C. Riddle, Ralph D. Nine, Benjie Staggs, V. Andy Williams, Timothy Hall 

and Sairam Thiagarajan. Heavy-Duty Vehicle Chassis Dynamometer Testing for 

Emissions Inventory, Air Quality Modeling, Source Apportionment and Air Toxics 

Emissions Inventory: Phase 1 Report: CRC Project No. E-55/E-59. West Virginia 

University, Morgantown: April 2003. 

Hallstrom. (2005). E-mail communication. Kevin Hallstrom. Engelhard Corporation 

 June 30, 2005 

Jay.(2005). Telephone Communication. Benny Jay. Idling Solutions, LLC. 

 June 30, 2005. 

Lambe. (2005). Personal Communication. Peter Lambe. Dinex Exhausts, Inc. 

 June 30, 2005 

Lambert, D.C., M. Vojtisek-Lom, and P. J. Wilson. Extended Idling Emissions Study -

Analysis and Final Report. Knoxville, February 2002. 

Lim, Han. Study of Exhaust Emissions from Idling Heavy-Duty Diesel Trucks and 

Commercially Available Idle-Reducing Devices. U.S. EPA Report: EPA420-R-02-

025, October 2002. 

Lutsey, Nicholas. Fuel cells For Auxiliary Power in Trucks: Requirements, Benefits, and 

Marketability. Institute of Transportation Studies, University of California, Davis. 

UCD-ITS-RR-03-04. July 2003. 

MECA. (2000). Catalyst-Based Diesel Particulate Filters and NOx Adsorbers: A 

Summary of the Technologies and the Effects of Fuel Sulfur. Manufacturers of 

Emission Controls Association. August 14, 2000. 

http://www.meca.org/jahia/Jahia/pid/229 

Perrot, Thomas L., Jeffrey C. Kim, Joseph D. Tario, and Colleen Hagan. Installation 

and Economics of a Shorepower Facility for Long-Haul Trucks. Antares Group 

Inc. September 2004 

RVIA. (2003). Letter from the Recreational Vehicle Industry Association to the ARB. 

July 18, 2003. 

Stodolsky, F., L. Gaines, and A. Vyas. Analysis of Technology Options to Reduce the 

Fuel Consumption of Idling Trucks. Argonne National Laboratory. ANL/ESD-43. 

June 2000. 
 56

Storey, John M. E., John F. Thomas, Samuel A. Lewis, Sr., Thang Q. Dam, K. Dean 

Edwards, Gerald L. DeVault and Dominic J. Retrossa. Particulate Matter and 

Aldehyde Emissions from Idling Heavy-Duty Diesel Trucks. Society of Automotive 

Engineers, 2003-01-0289 

U.S. Census Bureau. (2005). 2002 Vehicle Inventory and Use Survey Database

 U.S. Department of Commerce. April 13, 2005 

U.S. EPA. (2000). Regulatory Impact Analysis: Heavy-Duty Engine and Vehicle 

Standards and Highway Diesel Fuel Sulfur Control Requirements. 

December 2000. (EPA420-R-00-026). 

U.S. EPA. (2004). A Glance at Clean Freight Strategies: Idle Reduction. 

February 2004. (EPA 420-F-04-009). 

U.S. EPA. (2005). Currently Available Idle Reduction Technologies. Accessed: July 7, 

2005. (http://www.epa.gov/otaq/smartway/idlingtechnologies.htm) 

Wallace, John Paul. Modeling of Line-Haul Truck Auxiliary Power Units in ADVISOR 

2002. Institute of Transportation Studies, University of California, Davis. 

UCD-ITS-RR-03-07. August 2003. 
A- 1

APPENDIX A 

PROPOSED REGULATION ORDER 

Amend the following sections of Title 13, California Code of Regulations, to read as set 

forth in the following pages: 

§ 1956.8 Exhaust Emission Standards and Test Procedures 

for 1985 and Subsequent Model Year Heavy-Duty 

Engines and Vehicles 

§ 2404 Emission Control Labels and Consumer Information 

– 1995 and Later Small Off-Road Engines 

§ 2424 Emission Control Labels – 1996 and Later Off-Road 

Compression-Ignition Engines 

§ 2425 Defects Warranty Requirements for 1996 and Later 

Off-Road Compression-Ignition Engines 

§ 2485 Airborne Toxic Control Measure to Limit 

Diesel-Fueled Commercial Motor Vehicle Idling 

Notes: a) Paragraphs within the section that are not proposed 

for amendment in this rulemaking are indicated by 

"[No Change.]”. 

b) The proposed regulatory amendments are shown in 

underline to indicate additions to the text and strikeout to 

indicate deletions. 
A- 2

Amend Title 13, California Code of Regulations, § 1956.8, to read: 

§ 1956.8. Exhaust Emissions Standards and Test Procedures - 1985 and 

Subsequent Model Heavy-Duty Engines and Vehicles. 

(a)(1) [No Change.] 

(a)(2)(A) The exhaust emissions from new 2004 and subsequent model heavyduty diesel engines, heavy-duty natural gas-fueled and liquefied-petroleum-gasfueled engines derived from diesel-cycle engines, and heavy-duty methanolfueled diesel engines, and the optional, reduced-emission standards for 2002 

and subsequent model engines produced beginning October 1, 2002, except in 

all cases engines used in medium-duty vehicles, shall not exceed: 

Exhaust Emission Standards for 2004 and Subsequent Model Heavy-Duty Engines, 

and Optional, Reduced Emission Standards for 2002 and Subsequent Model HeavyDuty Engines Produced Beginning October 1, 2002, Other than Urban Bus Engines 

(grams per brake horsepower-hour [g/bhp-hr]) 

Model Year Oxides of 

Nitrogen Plus 

Non-methane 

Hydrocarbons 

Optional Oxides 

of Nitrogen Plus 

Non-methane 

Hydrocarbons 

Oxides 

of 

Nitrogen 

Non-methane 

Hydrocarbons 

Carbon 

Monoxid

e 

Particulates 

2004-2006H, 2.4 A,C,E,J 2.5 B,C,E,J n/a n/a 15.5 0.10 C

October 1, 2002 – 2006 n/a 1.8 to 0.3 A,D,F n/a n/a 15.5 0.03 to 0.01 G

2007 and subsequent n/a n/a 0.2 I 0.14 15.5 0.01 K 

A This is the standard for the arithmetic sum of the oxides of nitrogen exhaust component certification value and 

the non-methane hydrocarbon exhaust component certification value, without individual restriction on the 

individual component values. 

B

 This is the standard for the arithmetic sum of the oxides of nitrogen exhaust component certification value and 

the non-methane hydrocarbon exhaust component certification value, with the non-methane hydrocarbon 

individual component value not to exceed 0.5 g/bhp-hr. 

C

 For 2004 through 2006 model years, emissions averaging may be used to meet this standard. Averaging must be 

based on the requirements of the averaging, banking and trading programs described in “California Exhaust 

Emission Standards and Test Procedures for 1985 and Subsequent Model Heavy-Duty Diesel Engines and 

Vehicles” incorporated by reference in section 1956.8 (b), below. 

D A manufacturer may elect to certify to an optional reduced-emission NOx+NMHC standard between the values, 

inclusive, by 0.3 grams per brake horsepower-hour increments. Engines certified to any of these optional 

reduced-emission NOx standards are not eligible for participation in any averaging, banking or trading programs 

described in “California Exhaust Emission Standards and Test Procedures for 1985 and Subsequent Model 

Heavy-Duty Diesel Engines and Vehicles” incorporated by reference in section 1956.8 (b), below. 

E

 May be used as the certification standard for the higher emitting fueling mode of an engine certified under the 

dual fueling mode certification process of section 1956.8 (a)(4), below. 
A- 3

F

 May be used as the certification standard for the lower emitting fueling mode of an engine certified under the 

dual fueling mode certification process of section 1956.8 (a)(4), below. 

G A manufacturer may elect to certify to an optional reduced-emission PM standard between the specified values, 

inclusive, by 0.01 grams per brake horsepower-hour increments. Engines certified to any of these optional 

reduced-emission PM standards are not eligible for participation in any averaging, banking or trading programs 

described in “California Exhaust Emission Standards and Test Procedures for 1985 and Subsequent Model 

Heavy-Duty Diesel Engines and Vehicles” incorporated by reference in section 1956.8 (b), below. 

H Engine manufacturers subject to the Heavy-Duty Diesel Engine Settlement Agreements (Settlement 

Agreements)1

 must produce engines in compliance with the requirements contained in their respective 

Settlement Agreement. Most engine manufacturers subject to the Settlement Agreements are required to 

manufacture engines meeting the exhaust emission standards for 2004 and subsequent model years engines 

beginning October 1, 2002. 

I

 A manufacturer may elect to include any or all of its heavy-duty diesel engine families in any or all of the NOx 

emissions averaging, banking, or trading programs for heavy-duty diesel engines, within the restrictions 

described in "California Exhaust Emission Standards and Test Procedures for 1985 and Subsequent Model 

Heavy-Duty Diesel Engines and Vehicles" incorporated in section 1956.8 (b), below. If the manufacturer elects 

to include engine families in any of these programs, the NOx family emission limit (FEL) may not exceed the 

following FEL caps: 2.00 grams per brake horsepower-hour (0.75 grams per megajoule) for model years before 

2010; 0.50 grams per brake horsepower-hour (0.19 grams per megajoule) for model years 2010 and later. The 

FEL cap applies whether credits for the engine family are derived from averaging, banking, or trading programs. 

J

 For 2007 through 2009 model years, a manufacturer may use these emission standards in accordance with 

section 1956.8 (a)(2)(B). A manufacturer may elect to include any or all of its heavy-duty diesel engine families 

in any or all of the NOx plus NMHC emissions averaging, banking, or trading programs for heavy-duty diesel 

engines, within the restrictions described in "California Exhaust Emission Standards and Test Procedures for 

1985 and Subsequent Model Heavy-Duty Diesel Engines and Vehicles" incorporated in section 1956.8 (b), 

below. If the manufacturer elects to include engine families in any of these programs, the NOx family emission 

limit (FEL) may not exceed the following FEL caps: 2.00 grams per brake horsepower-hour (0.75 grams per 

megajoule) for model years. The FEL cap applies whether credits for the engine family are derived from 

averaging, banking, or trading programs. 

K A manufacturer may elect to include any or all of its heavy-duty diesel engine families in any or all of the 

particulate averaging, banking, or trading programs for heavy-duty diesel engines, within the restrictions 

described in “California Exhaust Emission Standards and Test Procedures for 1985 and Subsequent Model 

Heavy-Duty Diesel Engines and Vehicles” incorporated by reference in section 1956.8 (b), below. The 

particulate FEL for each engine family a manufacturer elects to include in any of these programs may not exceed 

an FEL cap of 0.02 grams per brake horsepower-hour (0.0075 grams per megajoule). The FEL cap applies 

whether credits for the engine family are derived from averaging, banking, or trading programs. 

(a)(2)(B) through (5) [No Change.] 

 

1

 Seven of the largest heavy-duty diesel engine manufacturers will be implementing measures to reduce 

emissions beginning October 1, 2002, to meet the requirements of the Heavy-Duty Diesel Engine 

Settlement Agreements reached with the ARB. The Heavy-Duty Diesel Engine Settlements were 

agreements reached in response to lawsuits brought by the United States Environmental Protection 

Agency and violations alleged by the ARB pertaining to excess in-use emissions caused by the use of 

defeat devices and unacceptable algorithms. Navistar signed its Settlement Agreement on October 22, 

1998. Cummins, Detroit Diesel Corporation, Caterpillar, Volvo, Mack and Renault signed their Settlement 

Agreements on December 15, 1998. 
A- 4

 (a)(6) Heavy-Duty Diesel Engine Idling Requirements.

(A) Engine Shutdown System. The requirements in this subsection apply 

to engine manufacturers and original equipment manufacturers, as applicable, 

that are responsible for the design and control of engine and/or vehicle idle 

controls. 

(i) Requirements: Except as provided in subsections (a)(6)(B) and 

(a)(6)(C), all new 2008 and subsequent model-year heavy-duty diesel engines 

shall be equipped with an engine shutdown system that automatically shuts down 

the engine after 300 seconds of continuous idling operation once the vehicle is 

stopped, the transmission is set to “neutral” or “park”, and the parking brake is 

engaged. If the parking brake is not engaged, then the engine shutdown system 

shall shut down the engine after 900 seconds of continuous idling operation once 

the vehicle is stopped and the transmission is set to “neutral” or “park.” The 

engine shutdown system must be tamper-resistant and non-programmable. A 

warning signal, such as a light or sound indicator inside the vehicle cabin, may 

be used to alert the driver 30 seconds prior to engine shutdown. The engine 

shutdown system must be capable of allowing the driver to reset the engine 

shutdown system timer by momentarily changing the position of the accelerator, 

brake, or clutch pedal, or other mechanism within 30 seconds prior to engine 

shutdown. Once reset, the engine shutdown system shall restart the engine 

shutdown sequence described in this paragraph above, and shall continue to do 

so until the engine shuts down or the vehicle is driven. 

 (ii) Engine Shutdown System Override: The engine shutdown 

system may be overridden, to allow the engine to run continuously at idle, only 

under the following conditions: 

 (I) If the engine is operating in power take-off (PTO) mode. 

The PTO system shall have a switch or a setting that can be switched “on” to 

override the engine shutdown system and will reset to the “off” position when the 

vehicle’s engine is turned off or when the PTO equipment is turned off. In 

addition, the PTO switch or setting shall be designed so that if it fails it will fail in 

the “off” position. Subject to advance Executive Officer approval, other methods 

for detecting or activating PTO operation may be allowed; or,

 (II) if the vehicle’s engine coolant temperature is below 60°F. 

The engine shutdown system shall automatically be activated once the coolant

temperature reaches 60°F or above. The engine coolant temperature shall be 

measured with the engine’s existing engine coolant temperature sensor used for 

engine protection, if so equipped. Other methods of measuring engine coolant

temperature may be allowed, subject to advance Executive Officer approval. 

(B) Exempt Vehicles. Heavy-duty diesel engines to be used in buses as 

defined in California Vehicle Code §§ 233, 612 and 642, school buses as defined 

in California Vehicle Code § 545, and recreational vehicles as defined in Health 

and Safety Code 18010 are exempted from these requirements.

(C) Optional NOx idling emission standard. In lieu of the engine shutdown 

system requirements specified in subsection (a)(6)(A) above, an engine 

manufacturer may elect to certify its new 2008 and subsequent model-year 
A- 5

heavy-duty diesel engines to an optional NOx idling emission standard of 30 

grams per hour, without increasing emissions of CO, PM, or ROG. Compliance 

with this optional standard will be determined based on testing conducted 

pursuant to the supplemental steady-state test cycle and procedures specified in 

section 86.1360-2007.B.4 of the “California Exhaust Emission Standards and 

Test Procedures for 2004 and Subsequent Model Heavy-Duty Diesel Engines 

and Vehicles”, adopted December 12, 2002, as last amended (amendment 

date), which is incorporated by reference herein. The manufacturer may request 

an alternative test procedure if the technology used cannot be demonstrated 

using the procedures in section 86.1360-2007.B.4, subject to advance approval 

of the Executive Officer. 

An engine manufacturer certifying its engine to the optional NOx idling 

emission standard must also produce a vehicle label, as defined in subsection 

35.B.4 of the “California Exhaust Emission Standards and Test Procedures for 

2004 and Subsequent Model Heavy-Duty Diesel Engines and Vehicles” adopted 

December 12, 2002, as last amended (amendment date), which is incorporated 

by 

(D) Optional Alternatives to Main Engine Idling. All new 2008 and 

subsequent model year heavy duty diesel engines may also be equipped with 

idling emission reduction devices that comply with the compliance requirements 

specified in title 13, CCR section 2485(c)(3). 

(b) through (h) [No Change.] 

NOTE: Authority cited: Sections 39600, 39601, 43013, 43018, 43101, 43102, 43104 

and 43105, Health and Safety Code; Sections 27156, 38390, 38391 and 38395, Vehicle 

Code. Reference: Sections 39002, 39003, 39500, 43000, 43013, 43017, 43018, 43100, 

43101, 43101.5, 43102, 43104, 43106, 43150-43154, 43202, 43204, 43205.5, 43206, 

43210, 43211, 43212 and 43213, Health and Safety Code. 
A- 6

Amend Title 13, California Code of Regulations, § 2404, to read: 

§ 2404. Emission Control Labels and Consumer Information – 1995 and Later 

Small Off-Road Engines. 

(a) Purpose. The Air Resources Board recognizes that certain emissions-critical or 

emissions-related parts must be properly identified and maintained in order for engines 

to meet the applicable emission standards. In addition, the Board recognizes that 

information regarding engines’ emissions levels may influence consumer choice. These 

specifications require engine or equipment manufacturers to affix a label (or labels) on 

each production engine (or equipment, as applicable) to provide the engine or 

equipment owner and service mechanic with information necessary for the proper 

maintenance of these parts in customer use. These specifications further require 

engine or equipment manufacturers to make information regarding relative emissions 

levels available to potential ultimate purchasers. For engines used in auxiliary power 

systems which, in turn, are used to comply with the diesel-fueled commercial vehicle 

idling requirements of title 13, CCR, section 2485(c)(3)(A), additional labeling 

requirements for the engine or equipment manufacturers apply, as set forth in section 

35.B.4 of the “California Exhaust Emission Standards and Test Procedures for 2004 

and Subsequent Model Heavy-Duty Diesel Engines and Vehicles” adopted December 

12, 2002, as last amended (amendment date), which is incorporated by reference 

herein. 

 (b) through (k) [No Change.] 

NOTE: Authority cited: Sections 39600, 39601, 43013, 43018, 43101, 43102 and 

43104, Health and Safety Code. Reference: Sections 43013, 43017, 43018, 43101,

43102, 43104, 43150-43154, 43205.5 and 43210-43212, Health and Safety Code.

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pt

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pt

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pt

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pt

Deleted: ¶
A- 7

Amend Title 13, California Code of Regulations, § 2424, to read: 

§ 2424. Emission Control Labels — 1996 and Later Off-Road CompressionIgnition Engines. 

(a) Purpose. The Air Resources Board recognizes that certain emissions-critical or 

emissions-related parts must be properly identified and maintained in order for engines 

to meet the applicable emission standards. The purpose of these specifications is to 

require engine manufacturers to affix a label (or labels) on each production engine (or 

equipment) to provide the engine or equipment owner and service mechanic with 

information necessary for the proper maintenance of these parts in customer use. For 

engines used in auxiliary power systems which, in turn, are used to comply with the

diesel-fueled commercial vehicle idling requirements of title 13, CCR, section 

2485(c)(3)(A), additional labeling requirements for the engine or equipment 

manufacturers apply, as set forth in section 35.B.4 of the “California Exhaust Emission 

Standards and Test Procedures for 2004 and Subsequent Model Heavy-Duty Diesel 

Engines and Vehicles” adopted December 12, 2002, as last amended (amendment 

date), which is incorporated by reference herein. 

(b) through (k) [No Change.] 

NOTE: Authority cited: Sections 39600, 39601, 43013, 43018, 43101, 43102 and 

43104, Health and Safety Code. Reference: Sections 43013, 43017, 43018, 43101, 

43102, 43104 and 43105, Health and Safety Code.
A- 8

Amend Title 13, California Code of Regulations, § 2425, to read: 

§ 2425. Defects Warranty Requirements for 1996 and Later Off-Road 

Compression-Ignition Engines. 

(a) through (d) [No Change.] 

(e) Each manufacturer shall furnish with each new engine written instructions for 

the maintenance and use of the engine by the owner. The instructions shall be 

consistent with this article and applicable regulations contained herein. In addition, for 

engines less than 19 kilowatts, each manufacturer shall furnish with each new engine a 

written statement as follows: “In order to operate in California, a diesel-fueled engine in 

an auxiliary power system used to comply with the Airborne Toxic Control Measure to 

Limit Diesel-Fueled Commercial Motor Vehicle Idling requirements of the California 

Code of Regulations, must have one of the following apply: (1) be equipped with a 

verified Level 3 in-use strategy for particulate matter control, (2) have its exhaust routed 

directly into the vehicle’s exhaust pipe, upstream of the diesel particulate matter 

aftertreatment device, or (3) use an alternate particulate matter control strategy with 

prior Executive Officer approval. (For more details, please see the California Code of 

Regulations, title 13, CCR, section 2485(c)(3)(A).)”

(f) through (g) [No Change.] 

NOTE: Authority cited: Sections 39600, 39601, 43013, 43018, 43101, 43102, 43104

and 43105, Health and Safety Code. Reference: Sections 43013, 43017, 43018, 

43101, 43102 and 43205.5, Health and Safety Code.
A- 9

Amend Title 13, California Code of Regulations, § 2485, to read: 

§ 2485. Airborne Toxic Control Measure to Limit Diesel-Fueled Commercial Motor 

Vehicle Idling. 

(a) Purpose. The purpose of this airborne toxic control measure is to reduce public 

exposure to diesel particulate matter and other air contaminants by limiting the 

idling of diesel-fueled commercial motor vehicles. 

(b) Applicability. This section applies to diesel-fueled commercial motor vehicles 

that operate in the State of California with gross vehicular weight ratings of 

greater than 10,000 pounds that are or must be licensed for operation on 

highways. This specifically includes: 

(1) California-based vehicles; and 

(2) Non-California-based vehicles. 

(c) Requirements. 

(1) Idling Restriction

On or after February 1, 2005, the driver of any vehicle subject to this section 

shall comply with the following requirements, except as noted in subsection 

(d) below: 

(1A) the driver shall not idle the vehicle’s primary diesel engine for greater 

than 5.0 minutes at any location., except as noted in subsection (d); and

(2B) the driver shall not operate a diesel-fueled auxiliary power system 

(APS) to power a heater, air conditioner, or any ancillary equipment on 

that vehicle during sleeping or resting in a sleeper berth for greater than 

5.0 minutes at any location when within 100 feet of a restricted area., 

except as noted in Subsection (d). 

(2) Use of Alternative Technologies 

(A) On or after January 1, 2008, the driver shall not operate an internal 

combustion APS on any vehicle equipped with a 2007 and subsequent 

model year primary diesel engine unless the vehicle is: 

(1) equipped with an APS meeting the emissions performance 

requirements found in subsection (c)(3)(A), below; and
A- 10

(2) the vehicle is equipped with a label meeting the requirements 

pursuant to section 35.B.4 of the “California Exhaust Emission 

Standards and Test Procedures for 2004 and Subsequent Model 

Heavy-Duty Diesel Engines and Vehicles” adopted December 12, 

2002, as last amended (amendment date) which is incorporate by 

reference herein. 

(B) On or after January 1, 2008, the driver shall not operate a fuel-fired 

heater on any vehicle equipped with a 2007 and subsequent model 

year primary diesel engine unless the fuel-fired heater meets the 

emissions performance requirements found in subsection (c)(3)(B), 

below; 

(C) On or after January 1, 2008, the driver of a vehicle equipped with a 

2006 or older model year primary diesel engine may use and operate in 

California any certified internal combustion APS with or without the 

additional PM control specified in subsection (c)(3)(A)(1) or any other 

certified alternative idling reduction technology. 

(3) Compliance Requirements. As an alternative to idling the primary engine, 

diesel engines/vehicles may, as an option, be equipped with alternative 

technologies, as listed and defined below in (A), (B), and (C) of this 

subsection. If so equipped, these technologies are subject to the following 

requirements: 

(A) Internal Combustion APS. 

(1) In order to operate in California, an APS utilizing an internal 

combustion engine must comply with applicable California off-road 

and/or federal non-road emission standards and test procedures for 

its fuel type and power category. In addition, diesel-fueled APSs 

installed on vehicles equipped with primary engines certified to the 

2007 and subsequent model year heavy-duty diesel engine 

standards, pursuant to section 1956.8(a)(2)(A) of title 13, CCR, 

shall either, 

(i) be equipped with a verified Level 3 in-use strategy for 

particulate matter control (see title 13, CCR, sections 2700 to 

2710), or 

(ii) have its exhaust routed directly into the vehicle’s exhaust pipe, 

upstream of the diesel particulate matter aftertreatment device. 

(2) With advance Executive Officer approval, a certifying/verifying APS 

manufacturer may petition for an alternate compliance strategy 
A- 11

other than described in (A)(1)(i) or (ii) in this subsection above. 

However, this provision is limited to manufacturers that can 

demonstrate, to the satisfaction of the Executive Officer, that their 

alternative strategy is equivalent (or “cleaner”), from an emissions 

standpoint, compared to the requirement described in (A)(1)(i) or (ii) 

in this subsection above. As an example, strategies that can use 

the available electric power infrastructure, instead of solely 

operating a diesel-fueled APS for engine and/or cab heating and 

cooling, may be able to use such a strategy to demonstrate 

compliance with these requirements. 

(B) Fuel-Fired Heaters. Fuel-fired heaters must comply with the applicable 

California emission standards and test procedures as specified in the 

Low Emission Vehicle program requirements found in title 13, CCR,

subsections 1961(a)(15) and (d), or in Part I.E.1.13 of the “California 

Exhaust Emission Standards and Test Procedures for 2001 and 

Subsequent Model Passenger Cars, Light-Duty Trucks and MediumDuty Vehicles” adopted August 5, 1999, as last amended May 28, 2004. 

However, the specified requirement that limits fuel-fired heaters from 

being operated above 40°F does not apply. 

(C) Other Idle Reduction Technologies. Other technologies that will reduce 

idling emissions may also be used, including the use of batteries, fuel 

cells, power inverter/chargers for on-shore electrical power, and other 

technologies that produce minimal or no emissions. The use of other 

technologies are subject to advance Executive Officer approval and 

must be at least as effective in reducing idling emissions as the 

technologies described in subsections (c)(3)(A), above, or the NOx 

idling emission standard specified in title 13, CCR, section 

1956.8(a)(6)(C). The Executive Officer shall use good engineering 

judgment and test data to determine if an idle reduction technology 

provides idling emission controls equivalent to the standards specified 

in subsection (c)(3)(A) above, or in title 13, CCR, subsection 

1956.8(a)(6)(C).

(D) Labeling Requirements. 2007 and subsequent model year commercial 

diesel vehicles equipped with an internal combustion APS meeting the 

requirements specified in subsection (c)(3)(A) shall have a label affixed 

to the hood of the vehicle to allow operation of the APS in California. 

The labels shall meet the requirements specified in section 35.B.4 of 

the “California Exhaust Emission Standards and Test Procedures for 

2004 and Subsequent Model Heavy-Duty Diesel Engines and Vehicles” 

adopted December 12, 2002, as last amended (amendment date), 

which is incorporated by reference herein.
A- 12

(d) Exceptions. 

(1) Except when a vehicle is located within 100 feet of a restricted area, 

subsection (c)(1)(A) does not apply, if the vehicle is equipped with 

 

(A) a primary diesel engine meeting the optional NOx idling emission 

standard pursuant to title 13, CCR, section 1956.8(a)(6)(C); and

(B) a label meeting the requirements pursuant to section 35.B.4 of the 

“California Exhaust Emission Standards and Test Procedures for 2004 

and Subsequent Model Heavy-Duty Diesel Engines and Vehicles” 

adopted December 12, 2002, as last amended (amendment date), 

which is incorporated by reference herein.

(2) Subsection (c)(1) does not apply for the period or periods during which 

(1A) a bus is idling for 

(A1) up to 10.0 minutes prior to passenger boarding, or 

(B2) when passengers are onboard; 

(2B) prior to January 1, 2008, idling of the primary diesel engine is 

necessary to power a heater, air conditioner, or any ancillary 

equipment during sleeping or resting in a sleeper berth. This 

provision does not apply when operating within 100 feet of a 

restricted area; 

(3C) idling when the vehicle must remain motionless due to traffic 

conditions, an official traffic control device, or an official traffic 

control signal over which the driver has no control, or at the 

direction of a peace officer, or operating a diesel-fueled APS or 

other device at the direction of a peace officer; 

(4D) idling when the vehicle is queuing that at all times is beyond 100 

feet from any restricted area; 

(5E) idling of the primary diesel engine, or operating a diesel-fueled 

APS, or operating other devices when forced to remain motionless 

due to immediate adverse weather conditions affecting the safe 

operation of the vehicle or due to mechanical difficulties over which 

the driver has no control; 

(6F) idling to verify that the vehicle is in safe operating condition as 

required by law and that all equipment is in good working order, 

either as part of a daily vehicle inspection or as otherwise needed, 

provided that such engine idling is mandatory for such verification; 
A- 13

(7G) idling of the primary diesel engine, or operating a diesel-fueled 

APS, or operating other devices is mandatory for testing, servicing, 

repairing, or diagnostic purposes; 

(8H) idling when positioning or providing a power source for equipment 

or operations, other than transporting passengers or propulsion, 

which involve a power take off or equivalent mechanism and is 

powered by the primary engine for: 

(A1) controlling cargo temperature, operating a lift, crane, pump, 

drill, hoist, mixer (such as a ready mix concrete truck), or 

other auxiliary equipment; 

(B2) providing mechanical extension to perform work functions for 

which the vehicle was designed and where substitute 

alternate means to idling are not reasonably available; or 

(C3) collection of solid waste or recyclable material by an entity 

authorized by contract, license, or permit by a school or local 

government; 

(9I) idling of the primary diesel engine, or operating a diesel-fueled 

APS, or operating other devices when operating defrosters, 

heaters, air conditioners, or other equipment solely to prevent a 

safety or health emergency; 

(10J) idling of the primary diesel engine, or operating a diesel-fueled 

APS, or operating other devices by authorized emergency vehicles 

while in the course of providing services for which the vehicle is 

designed; 

(11K) idling of military tactical vehicles during periods of training; and 

(12L) idling when operating equipment such as a wheelchair or people 

assist lift as prescribed by the Americans with Disabilities Act; 

(e) Relationship to Other Law. 

Nothing in this section allows idling in violation of other applicable law, including, 

but not limited to: 

(1) California Vehicle Code Section 22515; 

(2) Title 13, Section 2480, California Code of Regulations;

(3) California Health and Safety Code Section 40720; or 
A- 14

(4) any applicable ordinance, rule, or requirement as stringent as, or more 

stringent than, this section. 

(f) Enforcement. This section may be enforced by the Air Resources Board; peace 

officers as defined in California Penal Code, title 3, chapter 4.5, Sections 830 et 

seq. and their respective law enforcement agencies’ authorized representatives; 

and air pollution control or air quality management districts. 

(g) Penalties. For violations of subsection (c)(1), (c)(2) or (c)(23), the driver of a 

subject vehicle is subject to a minimum civil penalty of 100 dollars and to criminal 

penalties as specified in the Health and Safety Code and the Vehicle Code. 

(h) Definitions. 

The following definitions apply to this section: 

(1) “Authorized emergency vehicle” is as defined in Vehicle Code Section 

165. 

(2) “Auxiliary power system” or “APS” means any device that provides 

electrical, mechanical, or thermal energy to the primary diesel engine, 

truck cab, or sleeper berth as an alternative to idling the primary diesel 

engine. 

(3) “Bus” means any vehicle defined in Title 13, California Code of 

Regulations, Section 2480, subsections (h) (13)-(16), inclusive or as 

defined in the Vehicle Code Section 233. 

(4) “Commercial Motor Vehicle” means any vehicle or combination of vehicles 

defined in Vehicle Code Section 15210(b) and any other motor truck or 

bus with a gross vehicle weight rating of 10,001 pounds or more, except 

the following: 

 (A) a zero emission vehicle; or 

(B) a pickup truck as defined in Vehicle Code Section 471. 

(5) “Driver” is as defined in Vehicle Code Section 305. 

(6) “Fuel-fired heater” means a fuel burning device that creates heat for the 

purpose of (1) warming the cab or sleeper berth compartment of a vehicle 

or (2) warming the engine oil and/or coolant for easy start-up of the 

vehicle’s engine but does not contribute to the propulsion of the vehicle. 

(67) "Gross vehicle weight rating" is as defined in Vehicle Code Section 350. 

(78) “Highway” is as defined in Vehicle Code Section 360. 
A- 15

(89) “Idling" means the vehicle engine is running at any location while the 

vehicle is stationary. 

(910) "Motor truck" or "motortruck" means a motor vehicle designed, used, or 

maintained primarily for the transportation of property. 

(1011) "Official traffic control device" is as defined in Vehicle Code Section 440. 

(1112) “Official traffic control signal" is as defined in Vehicle Code Section 445. 

(1213) “Owner” is as defined in Vehicle Code Section 460. 

(1314) “Primary diesel engine” means the diesel-fueled engine used for vehicle 

propulsion. 

(1415) “Queuing” means (A) through (C) 

 (A) the intermittent starting and stopping of a vehicle; 

 (B) while the driver, in the normal course of doing business, is waiting 

to perform work or a service; and 

 (C) when shutting the vehicle engine off would impede the progress of 

the queue and is not practicable. 

 (D) Queuing does not include the time a driver may wait motionless in 

line in anticipation of the start of a workday or opening of a location 

where work or a service will be performed. 

(1516) “Restricted area” means any real property zoned for individual or 

multifamily housing units that has one or more of such units on it. 

(1617) "Safety or health emergency" means: 

 (A) a sudden, urgent, or usually unforeseen, occurrence; or 

 (B) a foreseeable occurrence relative to a medical or physiological 

condition. 

(1718) “Sleeper berth” is as defined in Title 13, California Code of Regulations, 

Section 1265.

(1819) “Vehicle” is as defined in the Vehicle Code Section 670. 

Authority: Sections 39600, 39601, 39614(b)(6)(A), 39658, 39667, 43000.5(d), 

43013(b), 43013(h), 43018(b), and 43018(c), Health and Safety Code; and 

Western Oil & Gas Assn. v. Orange County Air Pollution Control Dist. (1975) [14 

Cal.3d.411]. 

Reference: Sections 39002, 39003, 39027, 39500, 39600, 39650, 39655, 39656, 

39657, 39658, 39659, 39662, 39665, 39674, 39675, 42400, 42400.1, 42400.2, 

42400.3, 42402, 42402.1, 42402.2, 42402.3, 42403.5, 42410, 43013, 43018, 

Formatted: Font: 12 pt
A- 16

Health and Safety Code; Sections 305, 336, 350, 440, 445, 545, 546, 642, 680, 

21400, 22452, 22515, 27153, 40001, 40001(b)(5), Vehicle Code; and Sections 

1201,1900, 1962, 2480, Title13, California Code of Regulations. 
B-1 

APPENDIX B 

PROPOSED AMENDMENTS TO THE CALIFORNIA EXHAUST EMISSION 

STANDARDS AND TEST PROCEDURES FOR 2004 AND SUBSEQUENT MODEL 

HEAVY-DUTY DIESEL ENGINES AND VEHICLES
B-2 

State of California 

AIR RESOURCES BOARD

CALIFORNIA EXHAUST EMISSION STANDARDS AND TEST PROCEDURES 

FOR 2004 AND SUBSEQUENT MODEL 

HEAVY-DUTY DIESEL ENGINES AND VEHICLES

Adopted: December 12, 2002 

Amended: [Insert date of amendment]

NOTE: The proposed amendments are indicated by underline for additions and 

strikeout for deletions compared to the adopted test procedures. Only those 

portions of the existing language containing the proposed modifications are 

included. All other portions remain unchanged and are indicated by the 

symbol “* * * * *” for reference. A complete set of the adopted test 

procedures (without the proposed amendments) is available at 

http://www.arb.ca.gov/regact/levhdg02/levhdg02.htm . 
B-3 

CALIFORNIA EXHAUST EMISSION STANDARDS AND TEST PROCEDURES 

FOR 2004 AND SUBSEQUENT MODEL 

HEAVY-DUTY DIESEL ENGINES AND VEHICLES

The following provisions of Subparts A, I, and N, Part 86, Title 40, Code of 

Federal Regulations, as adopted or amended by the U.S. Environmental Protection 

Agency on the date set forth next to the 40 CFR Part 86 section listed below, and only 

to the extent they pertain to the testing and compliance of exhaust emissions from 

heavy-duty diesel engines and vehicles, are adopted and incorporated herein by this 

reference as the “California Exhaust Emission Standards and Test Procedures for 2004 

and Subsequent Model Heavy-Duty Diesel Engines and Vehicles,” except as altered or 

replaced by the provisions set forth below. 

Part I. GENERAL PROVISIONS FOR CERTIFICATION AND IN-USE VERIFICATION 

OF EMISSIONS. 

Subpart A - General Provisions for Emission Regulations for 1977 and Later 

Model Year New Light-Duty Vehicles, Light-Duty Trucks, and Heavy-Duty Engines, 

and for 1985 and Later Model Year New Gasoline-Fueled, Natural Gas-Fueled, 

Liquefied Petroleum Gas-Fueled and Methanol-Fueled Heavy-Duty Vehicles. 

1. General Applicability. [86.xxx-1] 

* * * * * 

11. Emission standards for diesel heavy-duty engines and vehicles. [§86.xxx-11] 

A. Federal provisions. 

* * * * * 

B. California provisions. 

1. Urban Bus Standards. 

* * * * * 

 

6. Heavy-Duty Diesel Engine Idling Requirements.

6.1 Engine Shutdown System. The requirements in this subsection 

apply to engine manufacturers and original equipment manufacturers, as 

applicable, that are responsible for the design and control of engine and/or 

vehicle idle controls. 

6.1.1 Requirements. Except as provided in subsections 11.B.6.2 

and 3, all new 2008 and subsequent model-year heavy-duty diesel 
B-4 

engines shall be equipped with an engine shutdown system that 

automatically shuts down the engine after 300 seconds of continuous 

idling operation once the vehicle is stopped, the transmission is set to 

“neutral” or “park”, and the parking brake is engaged. If the parking brake 

is not engaged, then the engine shutdown system shall shut down the 

engine after 900 seconds of continuous idling operation once the vehicle is 

stopped and the transmission is set to “neutral” or “park.” The engine 

shutdown system must be tamper-resistant and non-programmable. A 

warning signal, such as a light or sound indicator inside the vehicle cabin, 

may be used to alert the driver 30 seconds prior to engine shutdown. The 

engine shutdown system must be capable of allowing the driver to reset 

the engine shutdown system timer by momentarily changing the position 

of the accelerator, brake, or clutch pedal, or other mechanism within 30 

seconds prior to engine shutdown. Once reset, the engine shutdown 

system shall restart the engine shutdown sequence described in this 

paragraph above, and shall continue to do so until the engine shuts down 

or the vehicle is driven. 

6.1.2 Engine Shutdown System Override. The engine 

shutdown system may be overridden, to allow the engine to run 

continuously at idle, only under the following conditions: 

(1) If the engine is operating in power take-off (PTO) mode. 

The PTO system shall have a switch or a setting that can be 

switched “on” to override the engine shutdown system and will 

reset to the “off” position when the vehicle’s engine is turned off or 

when the PTO equipment is turned off. In addition, the PTO switch 

or setting shall be designed so that if it fails it will fail in the “off” 

position. Subject to advance Executive Officer approval, other 

methods for detecting or activating PTO operation may be allowed; 

or, 

(2) if the vehicle’s engine coolant temperature is below 60°F. 

 The engine shutdown system shall automatically be activated once 

the coolant temperature reaches 60°F or above. The engine 

coolant temperature shall be measured with the engine’s existing 

engine coolant temperature sensor used for engine protection, if so 

equipped. Other methods of measuring engine coolant

temperature may be allowed, subject to advance Executive Officer 

approval. 

6.2 Exempt Vehicles. Heavy-duty diesel engines to be used in buses 

as defined in California Vehicle Code §§ 233, 612 and 642, school buses as 

defined in California Vehicle Code § 545, and recreational vehicles as defined 

in Health and Safety Code 18010 are exempted from these requirements.

6.3 Optional NOx Idling Emission Standard. In lieu of the engine 

shutdown system requirements specified in subsection 11.B.6.1 above, an 

engine manufacturer may elect to certify its new 2008 and subsequent modelyear heavy-duty diesel engines to an optional NOx idling emission standard of 
B-5 

30 grams per hour, without increasing emissions of CO, PM, or ROG. 

Compliance with this optional standard will be determined based on testing 

conducted pursuant to the supplemental steady-state test cycle and

procedures specified in section 86.1360-2007.B.4, below. The manufacturer 

may request an alternative test procedure if the technology used cannot be 

demonstrated using the procedures in section 86.1360-2007.B.4, subject to 

advance approval of the Executive Officer.

An engine manufacturer certifying its engine to the optional NOx idling 

emission standard must also produce a vehicle label, as defined in subsection 

35.B.4, below. 

(D) Optional Alternatives to Main Engine Idling. All new 2008 and 

subsequent model year heavy duty diesel engines may also be equipped with 

idling emission reduction devices that comply with the compliance 

requirements specified in title 13, CCR section 2485(c)(3). 

* * * * * 

12. Alternative certification procedures. [§86.080-12] April 17, 1980. [No change.] 

* * * * * 

21. Application for certification. [§86.xxx-21] 

A. Federal provisions. 

* * * * * 

B. California provisions 

1. For 2004 and subsequent model-year medium-duty ultra-low emission and 

super-ultra-low emission vehicles and engines not powered exclusively by diesel 

fuel, the manufacturer shall submit projected California sales and fuel economy 

data two years prior to certification. 

2. Heavy-Duty Diesel Engine Idling Requirements. 

2.1 For 2008 and subsequent model-year heavy-duty diesel engines, 

the manufacturer must provide a statement in the application for certification 

that the heavy-duty diesel engine for which certification is being requested will 

comply with the automatic engine shutdown requirements to control idle 

emissions as specified in subsection 11.B.6.1. If the heavy-duty diesel 

engine for which certification is being requested is explicitly designed for 

exempt vehicles, per the provisions in 11.B.6.2, then the manufacturer must 

also provide a statement in its application for certification so stating. 

2.2 A manufacturer that elects to certify engines to the optional NOx 

idling emission standard, specified in subsection 11.B.6.3, must provide in the 

application for certification information pertaining to the NOx idling emission 

certification test conducted under 86.1360-2007.B.4, below, including 

emissions data for total particulate matter, non-methane hydrocarbons or total 
B-6 

hydrocarbons, oxides of nitrogen, carbon monoxide, and carbon dioxide in 

grams per hour, the test load in brake-horsepower, and engine test speeds in 

revolutions per minute for both mode 1 and mode 2 testing. With advance

Executive Officer approval, a manufacturer may use an alternative procedure 

to show compliance with the optional NOx idling emission standard. 

Regardless of the procedure used, the manufacturer shall also provide the 

appropriate labels to be affixed to the vehicle on which the engine is going to 

be installed as required in subsection 35.B.4, below. The manufacturer must 

maintain records at the manufacturer’s facility that contain all test data, 

engineering analyses, and other information which provide the basis for the 

compliance statement, where such information exists. The manufacturer 

must provide such information to the Executive Officer within 30 days upon 

request.

2.3 If the heavy-duty diesel engine for which certification is being 

requested incorporates any of the alternative idle emission control strategies 

contained in title 13, CCR, section 2485(c)(3), then the manufacturer must 

provide in its application for certification a description of the alternative 

strategy or technology including the type, brand name, model identification 

number, and where applicable emissions data and power rating. In addition, 

the manufacturer must also provide the appropriate labels to be affixed to the 

outside of the vehicle as required in subsections 35.B.4. If the alternative 

technology is a fuel-fired heater, then the manufacturer must provide with the 

application for certification the information required under subsection H.4.4, 

Part I of the “California Exhaust Emission Standards and Test Procedures for 

2001 and Subsequent Model Passenger Cars, Light-Duty Trucks and 

Medium-Duty Vehicles”, adopted August 5, 1999, as last amended May 28, 

2004.

22. Approval of application for certification; test fleet selections; determinations of 

parameters subject to adjustment for certification and Selective Enforcement Audit, 

adequacy of limits, and physically adjustable ranges. [§86.001-22] 

April 6, 1994. [No change.] 

* * * * * 

35. Labeling. [§86.xxx-35] ,

A. Federal Provisions. 

1. §86.001-35 January 18, 2001. 

1.1 Add the following sentence to the introductory paragraph: The 

labeling requirements of this section shall apply to all new motor vehicle 

engines certified according to the provisions of California Health and Safety 

Code Section 43100. 

1.2 Subparagraphs (a)(1) through (a)(3)(iii)(G). [No change.] 

1.3 Amend Add the following language to subparagraph (a)(3)(iii)(H) as 
B-7 

follows: . 

 1.3.1 An unconditional statement of compliance with the appropriate 

model year California regulations; for example, “This engine conforms to 

California regulations applicable to XXXX model year new heavy-duty diesel 

engines.” It may also state that the engine conforms to any applicable federal 

or Canadian emission standards for new heavy-duty diesel engines. 

1.3.21 For 2004 through 2006 model year heavy heavy-duty dieselfueled, dual-fuel, and bi-fuel engines to be used in urban buses that are 

certified to the optional reduced emission standards and are sold to any 

transit agency exempted under paragraphs (c)(8) and (d)(7), title 13, CCR, 

§1956.2 from the requirements of paragraphs (c)(5) and (d)(4), title 13, 

CCR §956.2. 

“This engine conforms to California regulations applicable to 

XXXX model year new urban bus or heavy-duty diesel engines 

and is certified to a NOx plus NMHC optional reduced-emission 

standards of XXX g/bhp-hr (for optional reduced-emission 

standards specify between 0.3 and 1.8, inclusive, at 0.3 b/bhphr increments, and a particulate matter standards of 0.01 g/bhphr).” 

1.3.32 For all other 2004 through 2006 model year heavy-duty diesel 

cycle engines, including those used in urban buses, that are certified to 

the optional reduced-emission standards, the label shall contain the 

following statement: 

“This engine conforms to California regulations applicable to 

XXXX model year new (specify urban bus or heavy-duty diesel) 

engines and is certified to a NOx plus NMHC optional reducedemission standards of XXX g/bhp-hr (for optional reducedemission standards specify between 0.3 and 1.8, inclusive, at 

0.3 b/bhp-hr increments, and a particulate matter standard of 

0.03 g/bhp-hr, 0.02 g/bhp-hr, or 0.01 g/bhp-hr).” 

1.4 Subparagraphs (a)(3)(I) through (i). [No change.] 

2. §86.007-35. January 18, 2001. 

2.1 Subparagraphs (a) through (i). [No change except that the 

amendments set forth in §86.001-35 apply.] 

B. California provisions. 

1. For 2004 and later model year heavy-duty diesel engines certified under 

the requirements of title 13, CCR, §1956.8(a)(3), the statement of compliance 

requirements of this subsection shall be repeated for each of the two fueling 

modes of operation. Appended to the statement for the lower emitting fueling 

mode of operation shall be the following sentence: 

“This certification is valid only while operating on ___ (indicate the fuel or 

fuel combination under which this mode of operation was certified) fuel. 
B-8 

Operation using any other fueling mode will result in significant increases 

in exhaust emissions and significantly reduce engine performance.” 

2. Manufacturers may elect to use a supplemental label in addition to the 

original label if there is not sufficient space to include all the required information. 

 The supplemental label must conform to all specifications as the original label. 

In the case that a supplemental label is used, the original label shall be 

numbered “1 of 2” and the supplemental label shall be numbered “2 of 2.” 

3. Statements shall not be used on labels placed on engines that, in fact, do 

not comply with all applicable California regulations. 

4. Vehicle Labels for Heavy-Duty Diesel Engine Idling Requirements. 

For each 2008 and subsequent model year heavy-duty diesel engine certified to 

the optional NOx idling emission standard pursuant to paragraph 11.B.6.3 or 

equipped with a certified/verified auxiliary power system (APS) pursuant to title 

13, CCR, section 2485(c)(3)(A), a single label shall be produced and affixed, as 

applicable, on each vehicle equipped with such heavy-duty diesel engine. 

4.1 The labeling requirements for engine manufacturers, aftermarket 

APS manufacturers and installers, and original equipment manufacturers are 

as follows: 

4.1.1 Engine manufacturers. The engine manufacturer that has 

certified an engine to the optional NOx idling emission standard pursuant 

to paragraph 11.B.6.3, or certified/verified an APS pursuant to title 13, 

CCR, section 2485(c)(3)(A), shall produce the appropriate label for each 

new engine or APS pursuant to paragraph 35.B.4.2, below. The label 

shall be affixed on the outside of the vehicle pursuant to paragraph 

35.B.4.3 by the original equipment manufacturer.

4.1.2 Aftermarket APS manufacturers and installers. An 

aftermarket APS manufacturer that has certified/verified an APS pursuant 

to title 13, CCR, section 2485(c)(3)(A), shall produce the appropriate label 

for each APS system pursuant to paragraph 35.B.4.2, below. The label 

shall be affixed on the outside of the vehicle pursuant to paragraph 

35.B.4.3 by the party that is responsible for installing the APS on the 

vehicle. 

4.1.3 Original equipment manufacturer. An original equipment 

manufacturer that has certified an engine to the optional NOx idling 

emission standard pursuant to paragraph 11.B.6.3, or certified/verified an 

APS pursuant to title 13, CCR, section 2485(c)(3)(A), shall produce and 

affix the appropriate label on the outside of the vehicle pursuant to 

paragraphs 35.B.4.2 or 35.B.4.3, whichever is applicable. 

4.2 Label Format. Figure 1 shows a facsimile of the label format for 

an engine certified to the optional NOx idling emission standard pursuant to 

paragraph 11.B.6.3. Figure 2 shows a facsimile of the label format for an 

engine in a certified/verified APS pursuant to title 13, CCR, section 
B-9 

2485(c)(3)(A). The engine manufacturer, APS manufacturer or original 

equipment manufacturer, whichever is applicable, that produces and affixes 

the label on the vehicle must ensure that the label has the following 

characteristics:

 Figure 1 Figure 2

4.2.1 Oval shape. 

4.2.2 Dimensions of no less than 6 inches wide by 4 inches high. 

4.2.3 The color of the outer and inner ellipses shall be dark blue

and the stars in red. The background of the label shall be light blue in 

color. The size of the stars shall be equal to the size of the characters as 

specified in paragraph 35.B.4.2.4 below. 

4.2.4 A vehicle equipped with an engine that is certified pursuant to 

paragraph 11.B.6.3 shall have a label with the word “CERTIFIED,” and 

below it the phrase “CLEAN IDLE,” as shown in Figure 1. A vehicle 

equipped with an APS certified/verified pursuant to title 13, CCR, section 

2485(c)(3)(A) shall have a label with the word “VERIFIED,” and below it 

the phrase “CLEAN APS,” as shown in Figure 2. The label information 

shall be written in the English language with sans serif font, black in color,

and in upper case letters. The size of the font shall be at least 7/16 inch 

(or 32 points) and the spacing of the fonts must be such that the longest 

phrase (for example, “CLEAN IDLE”) extends from the left edge to the 

right edge of the inner edge of the inner ellipse, without touching the 

edges. The label information shall be centrally aligned, both vertically and 

horizontally. 

4.2.5 A hologram as shown in Figure 3 shall be embedded within 

the proposed label. The hologram must cover the entire label. The 

hologram shall have the phrase “Clean Skies” repeatedly written from 

edge to edge of the label boundaries and each phrase shall be separated 

CCEERRTTIIFFIIEEDD

CCLLEEAANN IIDDLLEE

VVEERRIIFFIIEEDD

CCLLEEAANN AAPPSS
B-10 

by a circular bullet. The position of the circular bullet in each line shall be 

exactly above the space between the words “Clean” and “Skies” of the line 

below. The color of the font shall be orange. The font size“ shall be less 

than or equal to a quarter of the font size of the phrase “CLEAN IDLE” or 

“CLEAN APS” as specified in subsection 35.B.4.2.4, above. The 

hologram shall have the map of the State of California, in orange color, 

overlaid over the text and positioned in the center of the label as shown in 

Figure 3, below.

Figure 3

 4.3 Label Location and Attachment Requirements

4.3.1 The appropriate label shall be permanently affixed to the 

driver’s side of the hood, in an area within one foot by one foot from the 

top and front edges of the hood. If such an attachment is not feasible, the 

label may be attached at a different location subject to advance approval 

by the Executive Officer. 

4.3.2 Each label must be affixed in such a manner that it can not 

be removed without destroying or defacing the label. The label must not 

be affixed to any vehicle component that can easily be detached from the 

vehicle. 

 4.3.3 The label and any adhesives used must be designed to 

withstand, for a period of 10 years, typical environmental conditions. 

Typical environmental conditions include, but are not limited to, exposure 

to extreme heat or cold, moisture, engine fuels, lubricants and coolants. 

 4.4 The party that certifies/verifies the engine pursuant to paragraph 

11.B.6.3 or the APS pursuant to title 13, CCR, section 2485(c)(3)(A) shall be 

the ultimate party responsible for ensuring that the labels are correctly 

produced. Samples of labels produced pursuant to this subsection must be 

submitted to the Executive Officer with the applicable certification or 

verification application. 

4.5 Labels on vehicles may also be applied by distributors or dealers. 
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However, the party that certified the engine or the APS and produced the 

labels remains the ultimate party responsible for ensuring that the labels are 

correctly administered. If the labels are administered by the dealer or 

distributor, the producer of the label shall include its name and a serial 

number on the label. The location of the producer’s name and serial number 

on the label shall be written in the lower part of the label, in the space 

vertically centered between the label wording and the inner ellipses, and the 

font must contrast the label background. The serial numbers of the labels 

administered must be recorded by the distributor or dealer and reported to the 

party responsible for producing the labels. This information shall be 

maintained by the party responsible for producing the labels for a period of 10 

years, and shall be made available to the Executive Officer upon request. 

4.6 A heavy-duty diesel engine that has been certified pursuant to 

subsection 11.B.6.3 shall not be modified or altered unless said modification 

or alteration has been approved by the Executive Officer pursuant to title 13 

CCR sections 2220 through 2225. 

4.7 An idling emission reduction device or system that has been 

certified/verified pursuant to title 13, CCR, section 2485(c)(3)(A) shall not be 

modified or altered unless said modification or alteration has been approved 

by the Executive Officer pursuant to title 13 CCR sections 2470 through 2476.

36. Submission of vehicle identification numbers. [§86.079-36] [n/a] 

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PART II TEST PROCEDURES 

Subpart I - Emission Regulations for New Diesel-Fueled Heavy-Duty Engines; 

Smoke Exhaust Test Procedure 

* * * * * 

Subpart N - Emission Regulations for New Otto-Cycle and Diesel Heavy-Duty 

Engines; Gaseous and Particulate Exhaust Test Procedures 

* * * * * 

86.1360-2007 Supplemental steady-state test; test cycle and procedures. 

January 18, 2001. 

A. Federal provisions 

* * * * * 

B. California provisions 

1. Emission testing caps for the 2005 and subsequent model years. 

* * * * * 

4. Determination of NOx Idling Emissions. The requirements set forth in

this subparagraph apply to 2008 and subsequent model year heavy-duty diesel 

engines certifying to the optional NOx idling emission standard specified in 

subsection 11.B.6.3, above. To determine whether an engine meets the optional 

NOx idling emission standard, emissions shall be measured by testing the engine 

on an engine dynamometer as described below.

4.1 Test Cycle. The following 2 mode duty cycle shall be performed on 

a dynamometer on the test engine:

Mode Engine Speed 

(rpm) 

Time in mode 

(seconds) Engine Load 

1 Manufacturer 

Recommended Curb idle 1800 

See 

subparagraph 4.1.1

below 

2 1100 1800 

See 

subparagraph 4.1.2

below 

4.1.1 For mode 1, the dynamometer load or torque applied shall 

be based on the vehicle power requirements during curb idle operation. 
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The engine manufacturer shall determine the curb idle speed and the 

appropriate test load for the test engine. The load shall include curb idle 

power requirements needed for operating engine accessories, such as the 

engine cooling fan, alternator, coolant pump, air compressor, engine oil 

and fuel pumps and any other engine accessory operated during curb idle 

of the engine. The load for mode 1 may not include power requirements 

for operating the air conditioning compressor or for operating on-board 

accessories, such as a microwave, refrigerator, television, computer, etc., 

that the vehicle operator may use during rest periods.

4.1.2 For mode 2, the dynamometer load or torque applied shall 

be based on the vehicle power requirements during idle speed operations 

of 1100 revolutions per minute (rpm). The engine manufacturer shall 

determine the appropriate test load for the test engine. The load shall 

include high engine idle speed power requirements needed for operating 

engine accessories, such as the engine cooling fan, alternator, coolant 

pump, air compressor, engine oil and fuel pumps, air conditioning 

compressor set at maximum capacity, and any other engine accessory 

operated during the idle operation of the engine. The total test load shall 

be equal to the test load so determined plus an additional load of 2 

kilowatts to take into account the power needs for operating on-board 

accessories such as a television, refrigerator, microwave, computer, etc. 

4.2 Test Requirements.

4.2.1Pre-conditioning. Prior to measuring emissions, bring the 

engine to a warm condition as follows: 

(a) If the idling test follows directly after testing over the 

Federal Test Procedure or the supplemental emission tests, 

consider the engine warm. Bring down the engine to the 

manufacturer recommended curb idle speed, apply the appropriate 

load as determined in subparagraph 4.1.1, and start measuring 

emissions after 10 minutes and only after achieving temperature 

stability. Temperature stability may be determined as the point at 

which the engine coolant is within 2% of its mean value for at least 2 

minutes. 

(b) If the engine is cold, warm-up the engine by operating it at 

any speed above peak-torque speed and between 65 to 85% of 

maximum mapped power until the engine coolant temperature is 

within 2% of its mean value for at least 2 minutes or until the 

thermostat controls engine temperature. 

4.2.2Test Sequence. Following engine warm-up as described in 

subparagraph 4.2.1, the test shall be performed first for mode 1. Bring 

down the engine to the curb idle speed, apply the appropriate load as 

determined in subparagraph 4.1.1, and start measuring emissions after 10 

minutes and only after achieving temperature stability. Temperature 

stability may be determined as the point at which the engine coolant is 

within 2% of its mean value for at least 2 minutes. Upon completion of 
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mode 1 testing, the engine speed shall be ramped up to 1100 rpm. Once 

the engine starts operating at 1100 rpm, apply the appropriate load as 

determined in subparagraph 4.1.2, and start measuring emissions after 10 

minutes and only after achieving temperature stability. Temperature 

stability may be determined as the point at which the engine coolant is 

within 2% of its mean value for at least 2 minutes. The engine shall be 

operated for the prescribed time in each mode. The specified test speed 

shall be held to within ±50 rpm and the specified torque shall be held to 

within ±2 percent. 

4.2.3Calculations. For each test mode, calculate the modal 

average mass emissions level for each regulated pollutant, in grams per 

hour, the modal average power, in brake horsepower and the modal 

average speed, in rpm. 

86.1370-2007 Not-To-Exceed test procedures. January 18, 2001. 

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