BS EN 1092-1:2018 Flanges and their joints. Circular flanges for pipes, valves, fittings and accessories, PN designated Steel flanges

Dimensions
Temperature
Pressure
Ratings
Pipe couplings
Flanges
Circular shape
Flange facings
Threads
Pipe fittings
Surface treatment
Inspection
Welded joints
Marking
Testing
Steels
Bolting

Link: BS EN 1092-1:2018 Flanges and their joints. Circular flanges for pipes, valves, fittings and accessories, PN designated Steel flanges
Source: BSI Standards