On many occasions, I have come across specifications or standards   that contain rigid requirement which result in the exclusion of zinc die castings as a viable option. In many cases, these specs are unwarranted and have no engineering data to support it.  In some cases, we suspect they were put in place simply to eliminate zinc die castings as an option.  

Please add a comment below if you are aware of other specifications or standards that appear to incorrectly exclude zinc die castings.