In the State of Victoria:
Safety gear required for sailboards, which are defined as "off the beach sailing yachts" (see definitions on page 10), is shown in Schedule 3 , pages 163-4, 166 of the Marine Safety Regulations 2012.
www.legislation.vic.gov.au/ Compliance with the Regs is another issue.
Each State of Australia will have its own laws on the issue.
Have fun reading this stuff.
