Flight Instructor privileges to instruct for the IR are shown in Section XII on the licence as 'FCL.905.FI applies as in (g)' [example in CAP 804 Section 1 Part C Appendix 2 page 49], and to instruct for the IR(R) in UK-issued EASA licences as '(g)(IR(R))'. You can look up each of the letters included in FI privileges in FCL.905.FI which is reproduced in CAP 804, Section 4, Part J, Subpart 1, page 1.
A standalone IRI will be shown in Section XII on a separate line.
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