Record about new worker fully written out (8)
I believe the answer is:
longhand
'fully written out' is the definition.
(as opposed to written in shorthand)
'record about new worker' is the wordplay.
'record' becomes 'log' (logging is a kind of recording).
'about' means one lot of letters goes inside another.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'worker' becomes 'hand' (hand is a kind of worker).
'log' enclosing 'n' is 'long'.
'long'+'hand'='LONGHAND'
(Other definitions for longhand that I've seen before include "script" , "Ordinary writing - not typing or printing" , "Having words written out in full by hand" , "Ordinary writing of manual origin" , "It's normally written" .)