1994 Q1allegedly, but which one is it really?

[merlin89]

I have attached an answer for Part B 1994 question 1 all coments greatly appreciated. Thanks

[PJW]

I have attached an answer for Part B 1994 question 1 all coments greatly appreciated. Thanks

Your answer was pretty good and I think would have received decent marks.
However all your entries relate really to SAFETY; clearly it is THE primary purpose but the question did ask in the plural- indeed your answer at the beginning did acknowledge that this is only one of them.

Certainly should have mentioned:
OPTIMISING CAPACITY / ENABLING SHARED USE OF NETWORK (train paths to sell, making productive use of a given amount of infrastructure- in the extreme. if every train ran upon its own dedicated track without any level crossings etc there would be no need for any signalling at all but you'd need a lot of railway for little train service and would be very inflexible!). Similarly if trains went at walking pace always immediately following someone inspecting the track this may be very safe but of very little practical use.

Hence I'd also have mentioned:
a) being achievable for an economic price,
b) permitting trains to run at attractive speeds for the customer and making good use of the P'Way speed profile,
c) having a high enough level of reliability to deliver its promise consistently
i.e. signalling's purpose is to make a major contribution to the railway as an attractive means of transport for the community (and indeed the balance of Safety / Speed / Capacity / Reliability / Cost) could well be different in different environments. A railway only exits if it "serves its pupose"; in the totally commercial sphere this means "makes as much money as possible"; though this is often ameliorated by thoughts of "serving the community", "being environmentally responsible" fundamentally we mustn't lose sight that it is the provision of an attractive means of transport which is the goal rather than Safety per se.

Hence whereas there was very little wrong with your answer and at first sight it seems quite comprehensive, as ever with IRSE questions be careful to read the question precisely, do a bit of reading "between the lines" and think as widely as possible to give as much breadth as you can. It was certainly essential that you listed a good variety of the means by which a signalling contributes to safety but I think you gave a bit too much emphasis to these some of which were not really "purposes" but more a "means to an end".