It depends too on how they figure the death rate. For example the degree of fatality is usually compaired to exposure. It may be a number compared to total hours of worked of all in that field. For example deaths per manhour.
So if there were 10 military deaths compaired to 3 million manhours the rate is very small, 1/300,000. But if there were 10 ironworkers in 100,000 manhours it would be larger, 1/10,000. Thus......... more dangerous. (numbers for example purposes)
Military rates are more complex since they also include "off duty" time. Which includes natural causes, accidents, suicides , etc. Construction trade rates do not list off duty accidents, natural causes, etc.