EPA-420-B-12-012

February 2012

Transportation Conformity Rule Restructuring Amendments

Comparison Table

This comparison table is intended to assist readers in understanding how the conformity rule has been amended per 

the “Transportation Conformity Rule Restructuring Amendments” final rule (Docket # EPA-HQ-OAR-2009-0128). 

Sections of the conformity rule that have been amended are included in the table below. Sections of the transportation 

conformity rule that were not amended are not included in the table. 

Until these rule amendments are published in the Code of Federal Regulations (CFR), readers should refer to the final

rule for current regulatory requirements. 

Topic Previous

Conformity 

Rule

Section

Description of Previous Provision Updated

Provision

Purpose of Amendment

Definitions 93.101 Under “NAAQS,” paragraphs (1) through 

(6) identified specific NAAQS: “1-hour 

ozone NAAQS”, “8-hour ozone NAAQS”, 

“24-hour PM10 NAAQS”, “1997 PM2.5 

NAAQS”, “2006 PM2.5 NAAQS”, and 

“Annual PM10 NAAQS”

93.101 Removes the definitions for specific 

NAAQS; the conformity rule applies

to any ozone, CO, NO2, PM2.5 or 

PM10 NAAQS 

93.101 “Clean data” definition 93.101 Updates definition, no substantive 

change

Consultation 93.105(c)(1)(vi) Interagency consultation procedures: 

Specific processes

93.105(c)(1)(vi) Updates a reference; no other 

changes made

General 

Criteria and 

Procedures

93.109(b) Description of how 93.109 as a whole is 

structured

93.109(b) Updated to reflect revised structure: 

that paragraph (c) addresses the 

use of budget test and/or interim 

emissions test(s) and (d) addresses 

the hot-spot test; other references 

updated

Conformity 

Tests: Ozone 

93.109(c) 1-hour ozone areas N/A Deletes this section as it is no 

longer applicable. The 1-hour 

ozone NAAQS has been revoked.
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Topic Previous

Conformity 

Rule

Section

Description of Previous Provision Updated

Provision

Purpose of Amendment

93.109(d)(1) Use of 8-hour ozone budgets, once 

adequate or approved

93.109(c)(1) Addresses the use of the budget 

test and/or interim emissions test(s) 

93.109(d)(2) Use of interim emissions test(s) when no for all NAAQS 

ozone budgets 

93.109(c)(3)

93.109(d)(3) Use of interim emissions test(s) for NOx 

when no NOx budget

93.109(c)(4)

93.109(d)(4) Tests for areas not required to submit a 

SIP for ozone areas

93.109(c)(1), (c)(2), 

(c)(3)

93.109 (d)(5) Clean data option for moderate and above 

ozone areas

93.109(c)(5) Expands clean data flexibility to any 

NAAQS for which EPA has clean 

data regulations or policies

93.109(e)(1) Use of 8-hour ozone budgets, once 

adequate or approved

93.109(c)(1) Addresses the use of the budget 

test and/or interim emissions test(s) 

93.109(e)(2) Use of 1-hour ozone budgets before area for all NAAQS 

has 8-hour ozone budgets 

93.109(c)(2)

93.109(e)(3) Use of interim emissions test(s) when no 

ozone budgets

93.109(c)(3)

93.109(e)(4) Clean data option for moderate and above 

ozone areas

93.109(c)(5) Expands clean data flexibility to any 

NAAQS for which EPA has a clean 

data regulation and/or policy

Conformity 

Tests: CO

93.109(f)(1) FHWA/FTA projects in CO areas requiring 

a hot-spot analysis

93.109(d)(1) Redesignates paragraph (f)(1) to 

(d)(1)

93.109(f)(2) Use of CO budgets, once approved or 

adequate

93.109(c)(1) Addresses the use of the budget 

test and/or interim emissions test(s) 

93.109(f)(3) Use of interim emissions tests when no for all NAAQS 

CO budget

93.109(c)(3)

93.109(f)(4) Regional conformity tests in CO 

nonattainment areas that don’t have a 

maintenance plan and not required to 

submit an attainment demonstration

93.109(c)(1), (c)(2), 

(c)(3)

Conformity 

Tests: PM10 

93.109(g)(1) FHWA/FTA projects in PM10 areas 

requiring a hot-spot analysis

93.109(d)(2) Redesignates paragraph (g)(1) to 

(d)(2)
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Topic Previous

Conformity 

Rule

Section

Description of Previous Provision Updated

Provision

Purpose of Amendment

93.109(g)(2) Use of PM10 budgets, once approved or 

adequate

93.109(c)(1) Addresses the use of the budget 

test and/or interim emissions test(s) 

93.109(g)(3) Use of adequate or approved PM10 for all NAAQS 

budget of another PM10 NAAQS

93.109(c)(2)

93.109(g)(4)(i) Use of interim emissions tests when the 

area has no PM10 budget

93.109(c)(3)

93.109(g)(4)(ii) Use of interim emissions tests if the 

submitted PM10 SIP is a demonstration of 

impracticability under CAA 189(a)(1)(B)(ii) 

and does not demonstrate attainment

93.109(c)(6) Similar to previous rule provision 

but eliminates redundant language

Conformity 

Tests: NO2

93.109(h)(1) Use of NO2 budgets, once approved or 

adequate

93.109(c)(1) Addresses the use of the budget 

test and/or interim emissions test(s) 

93.109(h)(2) Use of interim emissions tests when area for all NAAQS 

has no NO2 budget

93.109(c)(3)

Conformity 

Tests: PM2.5

93.109(i)(1) FHWA/FTA projects in 1997 PM2.5 areas 

requiring a hot-spot analysis

93.109(d)(3) Includes hot-spot conformity test 

requirements for all PM2.5 areas

93.109(i)(2) Use of 1997 PM2.5 budgets, once 

approved or adequate

93.109(c)(1) Addresses all NAAQS

93.109(i)(3) Use of interim emissions tests when area 

has no PM2.5 budget

93.109(c)(3)

93.109(j)(1) FHWA/FTA projects in 2006 PM2.5 

requiring a hot-spot analysis

93.109(d)(3) Includes hot-spot conformity test 

requirements for all PM2.5 areas

93.109(j)(2) Use of 2006 PM2.5 budgets, once 

approved or adequate

93.109(c)(1) Addresses all NAAQS

93.109(j)(3) Use of interim emissions test 93.109(c)(3)

93.109(k)(1) FHWA/FTA projects in 2006 PM2.5 

requiring a hot-spot analysis

93.109(d)(3) Includes hot-spot conformity test 

requirements for all PM2.5 areas

93.109(k)(2) Use of 2006 PM2.5 budgets, once 

approved or adequate

93.109(c)(1) Addresses the use of the budget 

test and/or interim emissions test(s) 

93.109(k)(3) Use of 1997 PM2.5 budgets / interim for all NAAQS 

emission test

93.109(c)(3)
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Topic Previous

Conformity 

Rule

Section

Description of Previous Provision Updated

Provision

Purpose of Amendment

Conformity 

tests in ...

93.109(l) Areas with limited maintenance plans 93.109(e) Redesignates paragraphs (l)(m)(n) 

to (e)(f)(g); updates references in 

paragraph (g)(2) and revises 

reference in (g)(2)(iii)

93.109(m) Areas with insignificant motor vehicle 

emissions

93.109(f)

93.109(n) Isolated rural nonattainment and 

maintenance areas

93.109(g)

Hot-spot tests 

in...

93.116(b) CO areas without an approved attainment 

or maintenance plan

93.116(b) Updates references; no other 

changes made

Budget test 93.118(a) Introductory paragraph for the budget test 93.118(a) Updates references; no other 

changes made

93.118(b) Describes years for which consistency 

with budgets must be demonstrated 

93.118(b) Simplifies the provision by 

referencing 93.118(d)

Interim 

Emissions 

Tests

93.119(a) Introductory paragraph for interim 

emissions tests

93.119(a) Updates references; no other 

changes made

93.119(b) Ozone areas 93.119(b) Restructured so that the provision 

applies to current and future 

NAAQS without a rule revision 

(specific baseline years removed 

from these paragraphs and put into 

§93.119(e))

93.119(c) CO areas 93.119(c)

93.119(d) PM10 and NO2 areas 93.119(d) Combines existing 93.119(d) and 

(e) into (d). 

Restructured so that the provision 

applies to current and future 

NAAQS without a rule revision 

(specific baseline years removed 

from these paragraphs and put into 

§93.119(e))

93.119(e) PM2.5 areas 93.119(d)

Non-federal 

projects in...

93.121(b) Isolated rural nonattainment and 

maintenance areas

93.121(b) Updates references; no other 

changes made
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Topic Previous

Conformity 

Rule

Section

Description of Previous Provision Updated

Provision

Purpose of Amendment

93.121(c) Areas with limited maintenance plans and 

areas with insignificant motor vehicle 

emissions

93.121(c) Updates references; no other 

changes made