What does OML - Overall Migration Limit mean?

The Overall Migration Limit (OML) defines the maximum total amount of substances that may migrate from a plastic material into food.

It is one of the key parameters defined in EU Regulation No. 10/2011 governing all plastics intended for food contact. Migration is determined through standardized tests under defined time and temperature conditions – the so-called OM test conditions (OM1 to OM7).

These tests simulate realistic scenarios such as long-term storage at room temperature, heating in a water bath, or sterilization in an autoclave. The OML ensures that, even under worst-case conditions, the packaging does not release unacceptable levels of substances into the food.

For plastics in food contact, the legal limit is 10 mg/dm² (or 60 mg/kg of food if the surface-to-volume ratio is unknown). Additionally, specific components may be subject to SML limits (Specific Migration Limits), which restrict the migration of individual substances more strictly.

In short: The OML controls the overall migration of all components, while SML values regulate the migration of specific substances – together ensuring the safety of food packaging materials.