Yes, INCIDENT is a Scrabble word!

Letter values in Scrabble US: I 1, N 1, C 3, I 1, D 2, E 1, N 1, T 1.

Is it a valid word?

INCIDENT is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

falling or striking of light rays on something
(sometimes followed by `to') minor or casual or subordinate in significance or nature or occurring as a chance concomitant or consequence