In article ws.net,
"Doctor Drivel" writes:
My mothers house was new in 1953, was 250V, 3 pin plugs and radials.

There will undoubtedly be some variation across the country;
the building trade has always been quite regional. My parents
bought their house new in 1955, and by then the builders were
no longer offering round pin sockets -- a few years before you
could still ask for round pin sockets if you really wanted them.

Radials are not outlawed and rings are not mandatory. Even today it is take
your choice.

You can still install BS546 15A sockets on radials today if you
really want to, and have the installation conform to the current
wiring regs.

AFAICS, rings became common in the 1960s.

Radials were certainly gone by then, and 10 years earlier in
many places. Also note that both rings and fused plugs existed
before the 1946 supplement, but there was no standard. Fused
plugs from different manufacturers were not interchangable,
and I doubt the ring circuits were all standardised at 30A.
Some of the designs had the fuses as the plug prongs, and
some fused both prongs (as not all areas had a 'neutral').
There are tales of the fuses coming off and getting stuck
in the socket.

--
Andrew Gabriel