Brake Standard Open

British Rail Brake Standard Open
In service	1955–
Manufacturer	Mark 1: BR Doncaster, Wolverton and Gloucester RCW Mark 2: BR Derby
Family name	British Railways Mark 1, British Rail Mark 2
Constructed	Mark 1: 1955–1963 Mark 2: 1966–1974
Number built	340
Fleet numbers	9200–9539
Capacity	Mark 1: 39 Mark 2/A–D: 31 Mark 2E/F: 32
Operator(s)	British Rail
Specifications
Car length	66 ft 0 in (20.12 m)
Width	9 ft 3 in (2.82 m)
Height	12 ft 9 1⁄2 in (3.90 m)
Maximum speed	90–100 mph (145–161 km/h)
Weight	33 long tons (34 t; 37 short tons)
Train heating	Steam, Electric or both
Bogies	BR1, Commonwealth, or B4
Braking system(s)	Vacuum, Air, or both
Coupling system	Drop-head knuckle coupler on draw-hook
Track gauge	4 ft 8 1⁄2 in (1,435 mm) standard gauge

A Brake Standard Open or BSO, is a type of railway carriage used by British Rail. Both Mark 1 and Mark 2 types were built. Each consists of a standard class open passenger saloon with a centre aisle, a guard's compartment with hand brake and a lockable luggage compartment.

A number of Mark 1 and Mark 2 BSOs were converted to Brake Standard Open (Micro-Buffet) (BSOT), and fourteen Mark 2 BSOs were converted to Driving Brake Standard Open (DBSO). A number of BSO and BSOT coaches have been preserved, and some are still in use on main line charters.

Orders

See also

• Open coach