Trains carrying hazardous products and those with non standard buffing and/or couplings (such as coaches of multiple units) required barrier and runner wagons. There were various rules about them and they were frequently rebuilt from older revenue wagons. At depots reach wagons were used when it would be a hazard for the locomotive to go close to load/unload facilities.
DB924600 YSW BREAM @ Hoo Junction 85-10-12 � Paul Bartlett w
DB924644 YSW BREAM @ Woking 85-11-16 � Paul Bartlett w