Singapore legislation
Regulation 23
of Workplace Safety and Health (Explosive Powered Tools) Regulations 2009
Regulation 23
Use of tools on roof
It shall be the duty of any person who uses a tool to ensure that the tool is not used on any roof unless the area beneath the person —
(a)
has been cleared; and
(b)
is kept clear for a distance of 6 metres in every direction from the spot beneath the place where the person is working.