Another point: the section also states
 Personnel E-1 to E-3 have no rating and are thus called "non-rated men" or "non-rates;" however they are broadly classed into one of five groups of junior rates, Seaman (SN), Fireman (FN), Airman (AN), Hospitalman (HN) and Constructionman (CN).
 First, it almost looks like there is some slight mixing of terms (rate and rating) here.
 Second, for personnel who are E-1 to E-3, in reference to the "non-rated" and "non-rates" terms quoted in the text, you might want to add that what is frequently used for those who actually do not have a rating (usually because they failed out of their school) is the term "undesignated" which is used, for example, as "undesignated seaman" or "undesignated fireman apprentice", etc.
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