Yes, I think that it would be a really good thing to make a global occupational safety standards, and that a whole lot of people that are in the work force would get out of danger from this, and that they would have a lot less accidents in the world.
While it's a task that is virtually impossible for anybody to "complete" the knowledge that a large body is attempting to may fix some issues on their own. There are people all over the globe brutally exploited with no value given to their life for the means of obtaining or producing things, they need help.
The U.N. should work to establish global occupational safety standards. Yes, by all means. But they cannot be forceful with it like they and the United States so often are. Present ideas to these countries and perhaps even offer aid while you offer the ideas. This would be a global boon.
I don't believe this is an area the United Nation should be involved in at all, I believe workplace safety standards need to be set by Governments of each nation since circumstances are very different all over the world, I don't see how the UN could reasonably enforce any standards that they set.
Establishing global occupational safety standards can have a negative impact on developing countries who do not have the appropriate infrastructures or resources to implement such standards. Setting global standards gives those who already practice good safety standards the edge to go in underdeveloped areas and dominant in business, which would be unfair to the local business community.