Final answer:
The rule number for Blue Signal Protection of Workmen (Other Than Main Track 1) is Rule 404 of the Manual of Standards and Procedures for Railroad Engineering and Maintenance of Way (MSP). This rule outlines the requirements for using blue signals to protect workmen on tracks other than the main track.
Step-by-step explanation:
The rule number for Blue Signal Protection of Workmen (Other Than Main Track 1) is Rule 404 of the Manual of Standards and Procedures for Railroad Engineering and Maintenance of Way (MSP).
This rule outlines the requirements for using blue signals to protect workmen on tracks other than the main track. According to this rule, workmen must display blue signal equipment to indicate their presence and protect themselves from oncoming trains or equipment.
For example, if workmen are performing maintenance or repairs on a siding track, they must display blue signal flags, lamps, or lanterns to warn approaching trains. This visual signal alerts train operators to slow down and proceed with caution.