This action finalizes the residual risk and technology review (RTR) conducted for the Wet-Formed Fiberglass Mat Production source category regulated under national emission standards for hazardous air pollutants (NESHAP). In addition, we are taking final action addressing startup, shutdown, and malfunction (SSM), electronic reporting, and clarification of rule provisions. These final amendments address emissions during periods of SSM; add electronic reporting; revise certain monitoring, recordkeeping, and reporting requirements; and include other miscellaneous technical and editorial changes. These final amendments will result in improved compliance and implementation of the rule.