Just found some info about safety harnesses, child restraints thought I would share.
Only had a quick look my self, will read more after kids go to bed tonight.
Accessory child safety harnesses are available in some countries as alternative restraints for young children
or as an accessory restraint used with booster seats. Their use, in Australia at least, is becoming more
common. There have been concerns that the risk of misuse of these restraints outweighs any potential
benefit this systemmight have over a retractable lap–shoulder belt systemused with a booster seat.
For more info http://www.pscwa.org.au/getdoc/c563e...--July-09.aspx
D. CHILD RESTRAINTS IN AUSTRALIA
Note that, for more than two decades, Australia has required child restraints to have top tethers. In-depth accident studies show that child restraints with top tethers perform exceptionally well in severe crashes. Always attached the top tether to the approproate anchorage in the vehicle and tighten the tether.