ATTACHMENT 1 

15-DAY MODIFIED REGULATION ORDER 

REGULATION FOR IN-USE OFF-ROAD DIESEL VEHICLES

Amend sections 2449, 2449.1, and 2449.2, title 13, California Code of Regulations, to 

read as follows: 

Note: The regulation text, as presently adopted, filed with the Secretary of State, and 

operative is set forth below in normal type. This includes amendments that were 

approved for adoption at the July 23, 2009, Board hearing that were subject to the 

directives of Assembly Bill AB 8 2X, and not subject to the Administrative Procedure Act 

(APA) (Government Code section 36940 et seq.). Those amendments were adopted by 

the Board and became operative on December 3, 2009. It also includes the 

amendments adopted by the Board at its January 22, 2009, hearing, which were filed 

with the Secretary of State and became operative on December 31, 2009. The January 

2009 amendments were reflected in the Proposed Regulation Order for the July 23, 

2009 hearing in bold underline and bold strikeout, but, as stated, are not so reflected 

in Attachment 1. (A copy of the presently operative regulation that includes the January 

2009 amendments and the July 2009 AB 8 2X amendments is posted on ARB’s website 

at http://www.arb.ca.gov/msprog/ordiesel/documents/finalregorder-current.pdf 

The July 2009 amendments that are subject to the APA and were initially proposed to 

the Board at the July 2009 Board hearing are shown in underline to indicate additions 

and strikeout to indicate deletions. Modifications that are being proposed subsequent to 

the July 2009, Board hearing are shown in double underline to indicate additions and 

double strikeout to indicate deletions. The symbol “*****” indicates that regulatory 

language is not shown because it was not initially proposed for amendment or is not 

being modified. 

§ 2449 General Requirements for In-Use Off-Road Diesel-Fueled Fleets 

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(c) Definitions 

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(26) “Forest operations” means (A) forest fire prevention activities performed by 

public agencies, including but not limited to construction and maintenance of 

roads, fuel breaks, firebreaks, and fire hazard abatement or (B) cutting or 

removal or both of timber, other solid wood products, including Christmas trees, 

and biomass from forestlands for commercial purposes, together with all the work 

incidental thereto, including but not limited to, construction and maintenance of 

roads, fuel breaks, firebreaks, stream crossings, landings, skid trails, beds for 

falling trees, fire hazard abatement, and site preparation that involves 

disturbance of soil or burning of vegetation following forest removal activities. 
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Forest operations include the cutting or removal of trees, tops, limbs and or brush 

which is processed into lumber and other wood products, and or for landscaping 

materials, or biomass for electrical power generation. Forest operations do not 

include conversion of forestlands to other land uses such as residential or 

commercial developments. 

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(e) Special Provisions/Compliance Extensions

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(6) Compliance Extension for Equipment Manufacturer or Installer Delays - A fleet 

owner who has purchased new equipment (including VDECS) or vehicles in order to 

comply with this regulation, will be excused from immediate compliance if the new 

equipment or vehicles have not been received due to manufacturing or installer 

delays as long as all the conditions below are met:

(A) The equipment or vehicle was purchased, or the fleet owner and seller had 

entered into contractual agreement for the purchase, at least four months prior to 

the required compliance date, or - for a VDECS purchased to replace a failed or 

damaged VDECS – the fleet owner and seller had entered into contractual 

agreement for the purchase within 60 days of the VDECS failure. 

(B)Proof of purchase, such as a purchase order or signed contract for the sale, 

including engine specifications for each applicable piece of equipment, must be 

maintained by the fleet owner and provided to an agent or employee of ARB 

upon request. 

(C)The new equipment or vehicles are immediately placed into operation upon 

receipt. 

(D) Documentation from the manufacturer or the installer that there is a delay, 

such that the equipment or vehicle will be received or installed after the 

compliance date. 

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(8) VDECS That Impairs Safe Operation of Vehicle - A fleet owner may request that 

the Executive Officer find that a VDECS should not be considered the highest level 

VDECS available because (A) it cannot be safely installed or operated in a particular 

vehicle application, or (B) its use would make compliance with federal or state 

requirements for safety or health, occupational safety and health requirements, mining

safety and health requirements, or an ongoing local air district permit condition, such as 

for use of a diesel oxidation catalyst, impossible technologically infeasible. If a VDECS 

manufacturer states that there is no safe or appropriate method of mounting its VDECS 

on the requesting party’s vehicle, then the VDECS will not be considered safe. The 

Executive Officer shall accept the official findings of the responsible federal or state 

agency (i.e., the federal or state agency that promulgates safety requirements) that 

compliance with the requirements of this regulation would make compliance with the 

federal and state safety or health requirements impossible technologically infeasible. In 
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the absence of such a declaration by the VDECS manufacturer or official findings of a 

responsible federal or state agency, the requesting party shall provide other 

documentation to support its claims. Documentation must include published reports and 

other findings of federal, state or local government agencies, independent testing 

laboratories, engine or equipment manufacturers, or other equally reliable sources. The 

request will only be approved if the requesting party has made a thorough effort to find a 

safe method for installing and operating the VDECS, including considering the use of 

mirrors, various locations for VDECS mounting, and use of an actively regenerated 

VDECS. The Executive Officer shall review the documentation submitted and any other 

reliable information that he or she wishes to consider and shall make his or her 

determination based upon the totality of the evidence. Upon finding that a VDECS 

cannot be installed without violating the safety standards prescribed under federal or 

state requirements for safety or health occupational safety and health requirements, 

mining safety and health requirements, the Executive Officer shall issue a determination

that there is no highest level VDECS available. The Executive Officer shall inform the 

requesting party, in writing, of his or her determination, within 60 days of receipt of the 

request. Parties may appeal the Executive Officer’s determination as described in (A) 

and (B) below. During the appeal process described in (A) and (B) below, the 

requesting party may request the administrative law judge to stay compliance until a 

final decision is issued. If the stay is granted and the Executive Officer denies the 

requesting party’s request, the requesting party has six months from the date of the 

Executive Officer’s final written decision to bring his or her fleet back into compliance. 

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(g) Reporting – Reporting is required for each and every fleet. Large and medium 

fleets may report separately for different divisions or subsidiaries of a given company or 

agency. 

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(4) Selling Vehicles – Any person selling a vehicle with an engine subject to this 

regulation in California must notify ARB within 30 days from the date the vehicle was 

sold. If the reporting date under section 2449(g)(2) occurs within 30 days of the 

vehicle being sold, the annual reporting may serve as the notification to ARB that the 

vehicle was sold. 

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(h) Record keeping - Fleet owners must maintain copies of the information reported 

under section 2449(g), as well as the records described in section 2449(h) below, and 

provide them to an agent or employee of the ARB within five business days upon 

request. Records must be kept at a location within the State of California. 

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(8)(10) Record Retention – Each fleet owner shall maintain the records for each 

vehicle subject to the regulation for the overall fleet as long as the owner has a 

fleet or March 1, 2030, whichever is earlier. If vehicle ownership is transferred, 

the seller shall convey the vehicle records including vehicle data per section 

2449(g)(1)(B), engine data per section 2449(g)(1)(C), and VDECS data per 

section 2449(g)(1)(D) to the buyer. If fleet ownership is transferred, the seller 

shall convey the fleet records including fleet data per sections 2449(g)(1)(A) 

through (G) to the buyer. DealersAny person selling a vehicle with an engine 

subject to this regulation in California must maintain records of the disclosure of 

regulation applicability required by Section 2449(j) for three years after the sale. 

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Note: Authority cited: Sections 39002, 39515, 39516, 39600, 39601, 39602, 39650, 39656, 39658, 39659, 

39665, 39667, 39674, 39675, 40000, 41511, 42400, 42400.1, 42400.2, 42400.3.5, 42402, 42402.1, 

42402.2, 42402.4, 42403, 43000, 43000.5, 43013, 43016, 43018, and 43018.2, Health and Safety Code. 

Reference: Sections 39002, 39515, 39516, 39600, 39601, 39602, 39650, 39656, 39657, 39658, 39659, 

39665, 39667, 39674, 39675, 40000, 41511, 42400, 42400.1, 42400.2, 42402.2, 43000, 43000.5, 43013, 

43016, 43018, and 43018.2, Health and Safety Code. 

§ 2449.1 NOx Performance Requirements 

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(a) Performance Requirements

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(2) BACT Requirements – Each year, each fleet must determine if it will be able to 

meet the fleet average requirements for the next March 1 compliance date, and if 

not, the following BACT requirement must be met. If a fleet does not meet the 

NOx target rate in section 2449.1(a)(1), it must meet the BACT turnover 

requirements in section 2449.1(a)(2)(A) below. 

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(A) Turnover Requirements for Fleets Not Meeting NOx Target Rate – 

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1. Turnover Rate – If a fleet does not meet the NOx Target Rate in section 

2449.1(a)(1), it must demonstrate that it has turned over the required percent 

of the total maximum power of the fleet that existed on March 1 of the 

previous year since March 1 of the previous year. Any carryover turnover 

credit previously accrued may be applied towards the turnover required in a 

later year. The required turnover percents to demonstrate on each 

compliance date are described below in a. through e. 

a. 2010: 8 percent. 

b. 2011 and 2012: 4.8 percent. 
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c. 2013: 

i. 14.4 percent for large fleets that did not meet the NOx fleet 

 average target in 2011 or 2012, 

ii. 11.2 percent for large fleets that met the NOx fleet average target in 

2011 but not 2012, and 

iii. 8 percent for large fleets that (1) met the NOx fleet average target 

in 2012, (2) had all vehicles with a Tier 1 or higher engine qualify 

for a turn over exemption under section 2449.1(a)(2)(A)5, or (3) are 

not otherwise subject to the March 1, 2012, requirements per 

sections 2449.1(a)(1) and 2449.1(a)(2) and for all medium fleets. 

d. 2014 and 2015: 8 percent. 

e. 20152016 and later: 10 percent. 

2. Carryover turnover credit – 

a. Beginning - All fleets begin with zero carryover turnover credit on 

March 1, 2009. All fleets may begin accumulating carryover turnover 

credit on March 1, 2009. To claim credit, fleets must submit to ARB 

and retain records as described in sections 2449(g) and (h). 

i. Credit for Early Repowers - Fleets that have repowered their 

vehicles with Tier 1 or higher engines before March 1, 2009 begin 

with will accumulate a carryover turnover credit (in horsepower) 

equal to: the maximum power of Tier 1 or higher repower engines 

installed in affected vehicles before March 1, 2009. The credit can 

only be claimed for engines that remain in the fleet for the full 

duration of the year that the credit is taken. To claim credit, fleets 

must keep adequate records as described in section 2449(h). 

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iii. Double Credit for Early NOx Retrofits – Fleets that have installed 

VDECS that have been verified as achieving NOx reductions on 

their vehicles before March 1, 201109 begin with will accumulate a 

carryover turnover credit (in horsepower) equal to: 2 multiplied by

(Verified Percent NOx Reduction divided by 60 percent) multiplied 

by (Maximum power on which VDECS verified to achieve NOx 

reductions was installed before March 1, 201109). 

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b. Accumulating carryover turnover credit – 

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iii. Repower Credit– From March 1, 2010 through March 1, 2012, a 

medium fleet that did not accumulate any credit under (i) above 

shall accumulate carryover turnover credit each year equal to the 

total maximum power of Tier 2 or higher repower engines 

installed in affected vehicles in the 12 months prior to March 1 of 
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the year in which the carryover is calculated. From March 1, 2010 

through March 1, 2011, a large fleet that did not accumulate any 

credit under (i) above shall accumulate carryover turnover credit 

each year equal to the total maximum power of Tier 2 or higher 

repower engines installed in affected vehicles in the 12 months 

prior to March 1 of the year in which the carryover is calculated.

c. Using carryover turnover credit - Accumulated carryover turnover 

credit may be applied to meeting the turnover requirements of section 

2449.1(a)(2)(A)1 in a later year. The amount of carryover turnover 

credit used to meet the turnover requirements in any one year is 

subtracted from the carryover turnover credit total available in 

subsequent years. The amount of actual turnover plus the amount of 

carryover turnover credit used must equal the minimum BACT 

turnover required by section 2449.1(a)(2)(A)1. 

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3. Order of Turnover - All engines in a fleet that were not subject to a PM 

standard for new engines (Tier 0 and Tier 1 with no PM standard, i.e., Tier 1 

engines between 50 and 174 horsepower), except those in vehicles that qualify 

for an exemption under section 2449.1(a)(2)(A)4., must be turned over before 

turnover of any other higher tier engines may be counted toward the turnover 

requirements in section 2449.1(a)(2)(A) or toward accumulating carryover 

turnover credit. A fleet may, however, receive carryover turnover credit per 

section 2449.1(a)(2(A)2.a.iii for a VDECS verified to achieve NOx reductions 

installed on an engine, regardless of the engine’s tier. 

4. Exemptions - A vehicle is exempt from the turnover of section

2449.1(a)(2)(A)1. if all vehicles in the fleet that do not qualify for an exemption 

under this section have been turned over and the vehicle meets one of the 

following conditions: 

a. On the compliance date, the vehicle is less than 10 years old from the 

date of manufacture; 

b. The vehicle meets all of the following specialty vehicle criteria: 

i. The fleet has turned over all other vehicles first, 

ii. No repower is available for the specialty vehicle, as 

demonstrated to the Executive Officer, 

iii. A used vehicle with a cleaner engine is not available to serve a 

function and perform the work equivalent to that of the specialty 

vehicle, as demonstrated to the Executive Officer, and 

iv. The specialty vehicle has been retrofit with highest level VDECS, 

c. The vehicle has been retrofitted within the last six years with a Level 2 

or 3 VDECS that was highest level VDECS at the time of retrofit, or 

d. The vehicle has a Tier 4 interim or Tier 4 final engine. 

e. The vehicle has the highest level VDECS installed prior to March 1, 

2011, except that this exemption may be applied to no more than 15 

percent of a fleet’s total horsepower as of March 1, 2010.
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5. Delay Tier 1 Turnover - All vehicles with a Tier 1 or higher engine are exempt 

from the turnover requirement until the compliance year ending March 1, 2013 

(i.e., the first turnover of Tier 1 or higher engines would be required between 

March 2, 2012 and March 1, 2013), provided that all Tier 0 vehicles in the fleet 

owner’s fleet that do not qualify for an exemption under section 2449.1(a)(2)(A)4. 

have been turned over. 

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Note: Authority cited: Sections 39002, 39515, 39516, 39600, 39601, 39602, 39650, 39656, 39658, 39659, 

39665, 39667, 39674, 39675, 40000, 41511, 42400, 42400.1, 42400.2, 42400.3.5, 42402, 42402.1, 

42402.2, 42402.4, 42403, 43000, 43000.5, 43013, 43016, 43018, and 43018.2, Health and Safety Code. 

Reference: Sections 39002, 39515, 39516, 39600, 39601, 39602, 39650, 39656, 39657, 39658, 39659, 

39665, 39667, 39674, 39675, 40000, 41511, 42400, 42400.1, 42400.2, 42402.2, 43000, 43000.5, 43013, 

43016, 43018, and 43018.2, Health and Safety Code. 

§ 2449.2 PM Performance Requirements 

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(a) Performance Requirements - 

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(2) BACT Requirements – Each year, each fleet must determine if it will be able to 

meet the fleet average requirements for the next March 1 compliance date, and if 

not, the following BACT requirement must be met. If a fleet does not meet the 

Diesel PM Target Rate in section 2449.2(a)(1), it must meet the BACT Retrofit 

Requirements in section 2449.2(a)(2)(A). Fleets that fail to meet both an 

applicable NOx target rate in section 2449.1(a)(1) and the Diesel PM Target 

Rates in section 2449.2(a)(1) in a compliance year must first meet the BACT 

turnover requirements in section 2449.1(a)(2) in that year and then meet the 

BACT Retrofit Requirements in section 2449.2(a)(2)(A) in that year. 

(A) PM Retrofit Requirements for Fleets Not Meeting Diesel PM Target Rate 

1. PM Retrofit Rate - If a fleet does not meet the Diesel PM Target Rate in 

section 2449.2(a)(1), it must demonstrate that it has retrofit the 20 required

percent of its total maximum power (not including specialty vehicles retrofitted 

and exempted from turnover in section 2449.1(a)(2)(A)4.b.) with highest level 

VDECS since March 1 of the previous year, as described below. Any 

carryover retrofit credit previously accrued may be applied towards the 20 

percent retrofits required. If the VDECS is not new (i.e., is being reused), it 

must have been taken from a vehicle that is no longer operating in California. 

Fleets may count acquisition of vehicles with Tier 4 interim or Tier 4 final 

engines or retirement of Tier 0 vehicles toward the retrofit requirement, as 

described below. The required retrofit percents to demonstrate on each 

compliance date are described below:

2010: 20 percent.
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2011 and 2012: 12 percent. 

2013: 36 percent for large fleets that did not meet the PM fleet average 

target in 2011 or 2012, 28 percent for large fleets that met the PM 

fleet average target in 2011 but not 2012, and 20 percent for large 

fleets that met the PM fleet average target in 2012, for fleets that 

were not subject to required retrofit by March 1, 2012 per section 

2449.2(a)(2)(A), and for all medium fleets.

2014: 20 percent.

2. Carryover PM retrofit credit – 

a. Beginning - All fleets for vehicles remaining in their fleets begin with zero 

carryover retrofit credit on March 1, 2009. All fleets may begin 

accumulating carryover retrofit credit on March 1, 2009. 

i. Double Credit for Early PM Retrofits – Fleets that have installed the 

highest level VDECS on their vehicles before January 1, 2010 begin 

with will accumulate a carryover retrofit credit equal to: 2 multiplied by 

total maximum power of engines on which highest level VDECS was 

installed before January 1, 2010, unless the contract for funding the 

VDECS stipulates single credit for installation of the VDECS. 

ii. Single Credit for Other PM Retrofits Before Initial Compliance Date 

– Small and Mmedium fleets that install highest level VDECS on their 

vehicles between January 1, 2010 and February 29 before March 1, 

2012 will accumulate carryover retrofit credit equal to: 2 multiplied by

total maximum power of engines on which highest level VDECS was 

installed. Small fleets that install highest level VDECS on their 

vehicles between March 1, 2012January 1, 2010 and February 28, 

2014 accumulate carryover retrofit credit equal to total maximum 

power of engines on which highest level VDECS was installed. 

***** 

Note: Authority cited: Sections 39002, 39515, 39516, 39600, 39601, 39602, 39650, 39656, 39658, 39659, 

39665, 39667, 39674, 39675, 40000, 41511, 42400, 42400.1, 42400.2, 42400.3.5, 42402, 42402.1, 

42402.2, 42402.4, 42403, 43000, 43000.5, 43013, 43016, 43018, and 43018.2, Health and Safety Code. 

Reference: Sections 39002, 39515, 39516, 39600, 39601, 39602, 39650, 39656, 39657, 39658, 39659, 

39665, 39667, 39674, 39675, 40000, 41511, 42400, 42400.1, 42400.2, 42402.2, 43000, 43000.5, 43013, 

43016, 43018, and 43018.2, Health and Safety Code.