Regulations last checked for updates: May 18, 2024

Title 40 - Protection of Environment last revised: May 16, 2024
Appendix - Table W-1D to Subpart W of Part 98—Designation Of Eastern And Western U.S.
Link to an amendment published at 89 FR 42323, May 14, 2024.
Eastern U.S. Western U.S.
ConnecticutAlabama
DelawareAlaska
FloridaArizona
GeorgiaArkansas
IllinoisCalifornia
IndianaColorado
KentuckyHawaii
MaineIdaho
MarylandIowa
MassachusettsKansas
MichiganLouisiana
New HampshireMinnesota
New JerseyMississippi
New YorkMissouri
North CarolinaMontana
OhioNebraska
PennsylvaniaNevada
Rhode IslandNew Mexico
South CarolinaNorth Dakota
TennesseeOklahoma
VermontOregon
VirginiaSouth Dakota
West VirginiaTexas
WisconsinUtah
Washington
Wyoming
source: 74 FR 56374, Oct. 30, 2009, unless otherwise noted.