The Berne Gauge or Berne Convention Gauge is an informal but widely used term for the railway loading gauge considered the standard gauge in continental Europe. The term arises from the international railway conference held and consequent convention signed in Bern, Switzerland in 1912. The official name of this gauge is the Gabarit passe-partout international (PPI, literally "pass-everywhere international"), and it came into force in 1914.
The European (Berne) loading gauge is usually 3,150 mm (10 ft 4 in) wide by 3,175 mm (10 ft 5.0 in) rising to 4,280 mm (14 ft 1 in) in the centre. This is a clearance envelope (see loading gauge) on a curve of 250 m (820 ft 3 in) radius.
Previously, international through traffic, particularly freight, had been effectively constrained to vehicles and loads consistent with the standard French (with 1,500 V DC) loading gauge, the narrowest and lowest in Mainland Europe. As a result of accepting the convention, the French embarked on a period of progressive upgrade to make their network compliant.
Even after adopting the convention, significant parts of the European network[where?] operated to larger gauges, thus limiting the passing of traffic out of such areas.
- Hafter, G (April 1992). "Berne and all that". Modern Railways.