On 08/07/2011 13:26, GOG wrote:
OK, Perhaps I didn't really mean 'sealed', I guess. Covered so that dirt
doesn't fall into it. A lid, I guess. Possibly something to conform to
regulation ???30?

Although you can still buy the bits as a Byelaw 30 kit, Byelaw 30 was
replaced by Paragraph 16 of Schedule 2 to the Water Supply (Water
Fittings) Regulations 1999:

16.—(1) Every pipe supplying water connected to a storage cistern shall
be fitted with an effective adjustable valve capable of shutting off the
inflow of water at a suitable level below the overflowing level of the
cistern.

(2) Every inlet to a storage cistern, combined feed and expansion
cistern, WC flushing cistern or urinal flushing cistern shall be fitted
with a servicing value on the inlet pipe adjacent to the cistern.

(3) Every storage cistern, except one supplying water to the primary
circuit of a heating system, shall be fitted with a servicing valve on
the outlet pipe.

(4) Every storage cistern shall be fitted with–
(a)an overflow pipe, with a suitable means of warning of an impending
overflow, which excludes insects;.
(b)a cover positioned so as to exclude light and insects; and.
(c)thermal insulation to minimize freezing or undue warming..

(5) Every storage cistern shall be so installed as to minimize the risk
of contamination of stored water. The cistern shall be of an appropriate
size, and the pipe connections to the cistern shall be so positioned, as
to allow free circulation and to prevent areas of stagnant water from
developing.

Colin Bignell