On Dec 10, 11:48 pm, "John Rowland"
wrote:
Is there a good reason for them to be different? Won't various signs and
conduit friezes have to be replaced as a result of the colour change which
could otherwise have been left alone?

My guess is that they wanted something sufficiently different to
indicate different services, but sufficiently similar to merge them at
a later date.

PhilD

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