It seems every year brings its allotment of trench collapses which kill or seriously injure workers in Florida. After watching this tragedy for over 30 years and undertaking representation of a number of victims and their families my partners and I believe the OSHA standard for trenching is simply not on the reading list for some employers.
Maybe they would prefer to read what was said about trenching over 2300 years ago.
…the hazards of trenching — and how to prevent trenching casualties — were well known even before OSHA issued its standard — like somewhere around 2300 years before OSHA. Just ask Heroditus.
All the other nations, therefore, except the Phoenicians, had double labour; for the sides of the trench fell in continually, as could not but happen, since they made the width no greater at the top than it was required to be at the bottom. But the Phoenicians showed in this the skill which they are wont to exhibit in all their undertakings. For in the portion of the work which was allotted to them they began by making the trench at the top twice as wide as the prescribed measure, and then as they dug downwards approached the sides nearer and nearer together, so that when they reached the bottom their part of the work was of the same width as the rest.
— The Histories of Herodotus, The Persian Wars, Book 7 Polymnia, c. 484 – 425 BC
Thanks to Confined Space for the fascinating historical note.