Most horse people have been schooled in basic safety about riding- always wear a helmet, always wear a boot with a heel, check your girth after getting on, don't approach a horse from the rear and things like that. However, you'll note that these tips are all about keeping people safe. It's good to keep people safe. But a surprising number of experienced riders don't think enough about horse safety.
Although horses are very large, powerful animals they are surprisingly delicate and are very prone to injury. As prey animals they tend to panic easily and turn even the most minor mishap into a major crisis. They also have finicky digestive tracts, long skinny breakable legs and prehensile lips.