It depends on if you group together accidental deaths. Homicide is not number 2 if you break all the accidents out, for example, "vehicle accidents," "falls," etc. are both more frequent than homicides. If you group together accident-types, then homicide is number 2 and you will often see it referred to as such.

https://www.osha.gov/dte/grant_materials/fy03/46j3-ht47/prev...

I should have clarified that I can see how it would seem improbable.