A Permit-by-Rule (PBR) is an optional permit provision in the Ohio Administrative Code (OAC) that applies only to a certain type of air pollution source or facility. The PBR contains qualifying criteria, emission limitations, conditions for operation and requirements for record-keeping and reporting. Many of these requirements are similar to those found in typical air pollution permits issued by Ohio EPA. A PBR exempts the air pollution source from the formal Permit-to-Install and Operate (PTIO) process and effectively functions as both the installation and operating "permit" for the source.