In ascertaining for the purposes of section 19 of this Act the gross value of a hereditament, no account shall be taken—
(a)of any struoture belonging to the Minister of Health and supplied by that Minister or, before 31st August 1953, by the Minister of Pensions for the accommodation of an invalid chair or of any other vehicle (whether mechanically propelled or not) constructed or adapted for use by invalids or disabled persons; or
(b)of any structure belonging to a local health authority or to a voluntary organisation formed for any of the purposes mentioned in section 28(1) of the [1946 c. 81.] National Health Service Act 1946 (which relates to the prevention of, and to the care and after-care of persons suffering from, illness) and supplied for the use of any person in pursuance of arrangements made under the said section 28(1); or
(c)of any structure belonging to a local authority within the meaning of section 29 of the [1948 c. 29.] National Assistance Act 1948 (which relates to welfare arrangements for blind, deaf, dumb and other handicapped persons) or to such a voluntary organisation as is mentioned in section 30 of that Act and supplied for the use of any person in pursuance of arrangements made under the said section 29 ; or
(d)of any structure which is of a kind similar to structures such as are referred to in paragraph (a), (b) or (c) of this section but does not fall within that paragraph by reason that it is owned or has been supplied otherwise than as mentioned in that paragraph.