I've been flying freight for 14 years, and there have been a few incidences that actually caused problems, but most haz mat infractions are rather benign. Thats not to say i wouldn't like to see more diligence on the matter, but in reality, we don't really see that many real problems in the industry.
OH, don't get me wrong, there have been many bad ones, but all in all, with the percentage of cargo moved, the problems are few, and because we have so many variables in the cargo industry, there will never be a system of 100% safety. After all, people are involved! We fly to places around the world, that don't recognize things as dangerous, or just plain don't care! Hey, when its your time, its your time!