Carlisle - when I dealt with it from a freight business point of view , had early , late etc rolling stock examiners who were known as "tappers" , but they really dealt with anything arising on all trains. An excellent and dedicated bunch - complemented by the Shap team at Hardendale , who were really there for the limestone traffic , but like all dedicated railwaymen (father and son team) , could be relied to deal with almost anything arising / passing on the WCML.
The rulebook comment about "all staff must carefully observe passing trains for signs of distress , hot axle boxes , goods falling off" etc (quoted from memory) was embedded in these employees. Slightly off topic - "tappers" they might not have been , - but rolling stock inspectors they certainly were.