2009 Q9 Cab sight lines of new trains

[PJW]

Hi Peter,
Regarding 'Co-Actor' Signals.
the train operator shall have clear visibility of the signal or co-actor whilst:
a) Monitoring the safe closing of the doors;
b) Looking forward, from the normal driving position, in the direction of travel."

Does the wording imply a) AND b)? or a) OR b)?
Your exam answer seemed to suggest to me that the co-actor you were envisaging was associated with the cab side window looking out re the closure of the doors, not visible through the front window (which is why I raised the query)

'co-actors' may be placed on the otherside of the main signal, on a gantry in the front (further donw), sideways on a tight tunnel wall, etc.

I assume "otherside" is a typo for "underside"- although unusual we do have some NR examples (e.g. mini LEDs under the signals that are too high to view clearly from HST cab at Penzance). I assume that it doesn't actually mean the "back" of the signal- but there again historically sometimes a long train starting from a terminal platform on the mainline could have been beyond the actual position of the starting signal and "standing out" signals had to be provided so perhaps it does mean that......

Overall the wording quoted does seem to suggest that visibility through the front window is essential (or at least regarded as highly preferable) rather than the impression your answer seemed to be giving me.

Have I misunderstood?