Does a LED lighting fixture rated for installation in a Class I Div 2 area require a conduit seal? I would consider LED lighting not an ignition source as stated in 501.15 (A) (1). Correct?
Section 501.15(A) is for Division 1 and only applies to Division 2 if the luminaire is required to be explosionproof. [See Section 501.15(B)(1)]
You should begin with Section 501.130(B) and review the factory applied labels. They should indicate the luminaire's "T-Code" and whether auxiliary seals are required.
Luminaires have some unique "equipment" rules. Review Sections 500.8 (B) and (C), including the FPN/INs carefully.