The Navy blue coverall is designated as a dirty work component worn to perform work that would otherwise soil other Navy uniforms while performing the same task.  Wearing of the Navy blue coveralls is limited to the immediate area of assignment in which the work is to be performed.
 
Commanding Officers can authorize the wear of Navy blue coveralls ashore in environments that place an excessive amount of wear on working uniforms.  This policy does not alleviate the command's responsibility to procure coveralls for work in areas that are likely to permanently soil or prematurely destroy the uniform​.

See Footnotes