As Whale says for a purely residential complex the WH &S is not required and is not a legal requirement in NSW (applies to most states).
Their is nothing stopping you having one done or just getting the repairs done by the OC that you know are required (without a WH & S).
If you KNOW of a health and safety issue that the strata have been informed about your insurance for this issue could be in jeopardy (the same applies to a issue within your lot as well) whether you have had a WH & S done or not.
Submit a motion to the next AGM specifing
Their is a serious H & S issue with the XXX which needs fixing and I ask that the AGM authorize the EC to action the repairs within x months.
Now you have it on record what the issue is and you are asking the OC to authorize the EC to fix it.
If they vote the repairs down and you are so concerned you could go to conciliation and adjudication to get the repairs done.