Implementing an effective Listeria environmental monitoring program enables knowledge of where Listeria can enter, harbor, and move through a facility, which is the first step toward keeping the pathogen on the run and not allowing it to impact production surfaces or finished product.

Many methods are available for verifying the viability of a sanitation program, and most facilities use a combination of different methods to ensure that the sanitation program is performing as expected. Pathogen environmental monitoring (PEM) programs are a key prerequisite program to a sanitation program and to any facility's overall food safety program. There is no one-size-fits-all PEM program for facilities; rather, a PEM program is based on a facility's risk factors and what product(s) the facility manufactures.