EPA withdrew an October 2020 Trump administration policy allowing states to be exempted from air emissions regulations during facility start-up, shutdown, or malfunction (SSM). The Agency reverted back to a 2015 policy that requires states to remove these exemptions from their state implementation plans (SIPs). This change is particularly significant for fenceline communities who are exposed to toxic emissions during the startup and shutdown of facilities. This memorandum is just guidance and was intended to provide clarity about EPA’s policy on the permissibility of SSM provisions in SIPs. The guidance did not bind states as EPA’s evaluation of SIP submission will go through notice-and-comment proceedings.