Connections in a Class I, Div 2 area subject to submergence

[lakee911]

I have a valve vault that is rated Class I, Div. 2 (per NFPA 820: 4.2-31a) and is subject to submergence.

In this valve vault I have the following:
* an intrinsically safe high level float switch (for alarm)
* a 240VAC hazardous-area rated submersible sump pump
* a 120VAC hazardous-area rated valve actuator (that can be submerged)

Obviously I would need conduit seals as soon as the conduits enter the vault, but then how do I make my connections? Do I need an explosion-proof (NEMA 7) water-tight (NEMA 6) junction box?

How would this change if it was rated Class I, Div. 1??

Thanks,
Jason

 

[rbalex]

The explanitory material in Appendix A [Figure A.4.2(e)] indicates Table 4.2, Line 31a applies to a Dry Vault. Why is it being applied to an installation that is "...subject to submergence?"