Hello aspirant,
Well the Civil Service Conduct Rules, does not mention anything about tattoos or piercings. Now if the tattoos are visible it may lead to some questions from one's interview panel but I don't feel they would outrightly disqualify a person just because of his/her tattoo.
You are not expected to behave like ‘unbecoming of a govt officer’ according to this clause you should avoid wearing tattoos on those parts of the body which are exposed to the public.
Hope it helps you..
Best of luck..
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