tired of all the interpretations people come up with. so here are the relevant regs... suggest you make your own conclusions...
1. cao 20.9
http://www.casa.gov.au/wcmswr/_asset...cao20/2009.pdf
2. cao 20.9
http://www.casa.gov.au/wcmswr/_asset...cao20/2009.pdf
3. cant find reference excpt my company manual