From the USA Swimming Rules and Regulations booklet 

1.  under 302.1 all athletes must be currently registered with USA Swimming as an athlete; 

2.  under 202.3.3 meet directors, referees, starters, stroke & turn officials and all persons acting in any coaching capacity in a sanctioned event must be coach members of USA Swimming.

Thus,

Meet directors must be currently registered with USA Swimming at least as Other; (can be registered differently but must be currently registered)

Referees, Starters and Stroke & Turn Officials must be currently registered with USA Swimming as Officials;
and all persons acting in any coaching capacity in a sanctioned event must be currently registered COACH members of USA Swimming.