... Is there a book someone could recommend on the subject?
I've said in other topics and posts that classified locations isn't rocket science but it isn't quite trivial either. In this case, the "book" you referred to is the NEC, Articles 500 and 502 supplemented with NFPA 499,
Recommended Practice for the Classification of Combustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas.
It is essential that the classified locations be properly documented as required by Section 500.4(A). NFPA 499 is one of the Reference Standards listed in Section 500.4(B) FPN/INs.
Once proper classifications have been established, suitable wiring methods for the classified locations can be selected directly from Section 502.10.
For Class II, sealing is not too complicated [502.15], just be careful to identify enclosures that are
required to be
dust-ignitionproof. The requirements for Divisions 1 and 2 are virtually identical in Class II.
NOTE: This statement may change with the 2017 NEC where "dust-ignitionproof" may become a somewhat obsolete term.
Grounding and bonding may present a few challenges [502.30]; however, most ordinary standard practices are acceptable. Again, Divisions 1 and 2 are virtually identical in Class II.