Assertion: defect detector | /r/HasProperty | brittle bars
Facets:
value: by the 1940s
type: TEMPORAL
Source sentences:
text: By the 1940s, automatic defect detectors included infrared sensors for hotboxes, wires outlining the clearance envelope to detect high and wide loads, and "brittle bars" – frangible bars mounted between the rails – to detect dragging equipment.