19.—(1) All practicable steps must be taken, where necessary to prevent danger to any person, to ensure that any new or existing structure does not collapse if, due to the carrying out of construction work, it—
(a)may become unstable; or
(b)is in a temporary state of weakness or instability.
(2) Any buttress, temporary support or temporary structure must—
(a)be of such design and installed and maintained so as to withstand any foreseeable loads which may be imposed on it; and
(b)only be used for the purposes for which it was designed and installed and is maintained.
(3) A structure must not be so loaded as to render it unsafe to any person.