Best practices for readability for Annual Required Training

Content

All of our employees from food service to the executives have to complete the same set of online courses to meet various regulatory training. Some of our content owners (SME) resist simplying language and want to present their content using the exact language that is in state and federal laws from the statutes. As you can imagine this makes it very hard for learners who might not have a legal degree or don't speak english as their primary language. Does anyone have any best practices or know of any research on what grade level annual required training should be written