98. Taking account of the general principles of prevention in Schedule 3 to the Act, an employer shall—

(a) ensure that work is not carried out at height where it is reasonably practicable to carry out the work safely and without risk to health otherwise than at height,

(b) without prejudice to the generality of paragraph (a), ensure that work is not carried out at height unless it is reasonably practicable to do so safely and without risk to health,

(c) where, having regard to paragraphs (a) and (b), it is necessary to carry out work at height, take suitable and sufficient measures to prevent an employee falling a distance liable to cause personal injury, including—

(i) ensuring that the work is carried out—

(I) from an existing place of work, or

(II) in the case of obtaining access or egress, by using an existing means of access or egress,

in compliance with this Part, where it is practicable to do so safely and under appropriate ergonomic conditions, and

(ii) where it is not practicable for the work to be carried out in accordance with subparagraph (i), ensuring that suitable and sufficient work equipment, in compliance with Regulation 100, is provided to prevent a fall occurring,

(d) where the measures taken under paragraph (c) do not eliminate the risk of a fall occurring—

(i) provide sufficient work equipment, in compliance with Regulation 100, to minimise the distance of a potential fall and the risk of personal injury, and

(ii) without prejudice to the generality of paragraph (c), provide such additional training and instruction or take other additional suitable and sufficient measures to prevent, so far as is practicable, any employee falling a distance liable to cause personal injury.