(a) Any public building, the initial construction of which is commenced after July 1, 1978, shall be so designed and constructed as to provide reasonable means of ingress and egress by the physically disabled, with the exception of:
(1) jails or other places of detention;
(2) garages, hangars, and boathouses;
(3) all buildings which are hazardous for occupation by members of the general public, including electric power generating facilities, water treatment facilities and such other facilities as may be so classified by regulation of the Police Commissioner;
(4) warehouses; and
(5) buildings specifically constructed for field service purposes.
(b) The requirements of subsection (a) of this section may be accomplished by at least one ground or street level entrance and exit without steps, by ramps with slopes not more than one foot of rise in 12 feet, coated with a non-skid surface, or by elevator or such other arrangements as may be reasonably appropriate under the circumstances and which meet with the approval of the Commissioner of Planning and Natural Resources. The doors of such entrance and exit must have a clear opening of at least 40 inches in width and shall otherwise conform to the building code requirements contained in chapter 5 of this title.
(c) If any ground or street level entrance or exit is not so designed or constructed, a sign shall be placed at such entrance or exit indicating the location of the entrance or exit available for wheelchair service.
(d) The Commissioner of Planning and Natural Resources shall promulgate regulations to establish minimum standards to ensure the access to and use of public buildings contemplated by and not excepted from the requirements of this section.