Usually, certain periods during rush-hours are exempt from such strikes but, for the first time since 2005, Friday’s protest will not contain any blocks of time in which services are guaranteed.
The strike was called by Filt Cgil, Fit Cisl, Uiltrasporti, Faisa Cisal and Ugl Fna over the failure to renew the sector’s collective labour contract and the lack of resources devoted to it.
They also called for better health and safety.
The unions will also stage a demonstration outside the transport ministry in Rome on Friday.
An eight-hour strike of railway workers was held across Italy on Tuesday after a ticket inspector working on a regional train was stabbed near the Liguria station of Rivarolo.
ANSA