23.—(1) A cofferdam or caisson must be—
(a)of suitable design and construction;
(b)appropriately equipped so that workers can gain shelter or escape if water or materials enter it; and
(c)properly maintained.
(2) A cofferdam or caisson must not be used to carry out construction work unless—
(a)the cofferdam or caisson and any work equipment and materials which may affect its safety have been inspected by a competent person—
(i)at the start of the shift in which the work is to be carried out; and
(ii)after any event likely to have affected the strength or stability of the cofferdam or caisson; and
(b)the person who carried out the inspection is satisfied that construction work can be safely carried out there.
(3) Where the person carrying out an inspection informs the person on whose behalf the inspection is carried out of any matter about which they are not satisfied (under regulation 24(1)), construction work must not be carried out in the cofferdam or caisson until the matter has been satisfactorily remedied.