This family of measures consists of access restriction or limitation by fences and other physical barriers at specific parts of stations to prevent unauthorised access to the rails.

It is considered a physical family because it physically influences the accessibility and potential collision, or eliminates the possibility of direct contact between persons and moving trains.

Measures in this family are often referred to as: obstructive measures, exclusion measures, access restriction, access control, electronic entrance gates, closing the access, barriers, engineering, limitation by fencing, or limitation of pedestrian access to the tracks.