Hi everyone.
I have come across too many windsurfers lately who don't think they need to wear a PFD while sailing. Sorry but you do and in all SA waters, fresh or salt.
Below is a copy and paste of the relevant section of the Harbors and Navigation Regulations, Jan 2011.
(Underline and bold added)

169—Personal flotation devices to be worn on certain recreational vessels
(1) Each occupant of—
(a) a vessel (other than a surfboard, surf ski or racing shell) that can only carry
the operator and no other person; or
(b) a surfboard, surf ski or similar vessel that is being operated in inland waters;
or
(c) a sailboard or kiteboard; or