99. An employer shall ensure that a place of work, or means of access or egress thereto, at which work at height is, or is to be, carried on—

(a) is stable and of sufficient strength and rigidity for the purpose for which it is intended to be or is being used,

(b) where applicable, rests on a stable, sufficiently strong surface,

(c) is of sufficient dimensions to permit the safe passage of employees and the safe use of any plant or materials required to be used and provide a safe working area having regard to the work to be carried out there,

(d) is provided with suitable and sufficient edge protection,

(e) possesses a surface that has no gap—

(i) through which an employee could fall,

(ii) through which any material or object could fall and injure an employee, or

(iii) giving rise to other risk of injury to any employee, unless measures have been taken to ensure that no employee could be so injured,

(f) is so constructed, used and maintained in such condition as to prevent, so far as is reasonably practicable—

(i) the risk of slipping or tripping, or

(ii) any employee being caught between it and any adjacent structure, and

(g) where it has moving parts, is prevented by appropriate devices from moving inadvertently during work at height.