As previously mentioned by others, you will need to find out what Chemicals are being stored - along with the "Strength", then base the Class/Division of the installation upon the hazard of the materials involved.

For instance, if the Classified Material is Hydrogen Peroxide 3%, this would be a minor corrosive and minor hazard (may not require wiring per article 500).

However, Hydrogen Peroxide >26% would be Classified as an Oxidizer (Reducing Agent), and therefore would be a hazardous Material.

What the Fire Department designates classification will effect your installation requirements.

As mentioned by others, verify with the Building Department &/or Client, as to the hazard of the Material used or stored.

References should be reflected from the _Approved Plans_, and what is denoted regarding the "Hazardous Location(s) Boundary(s)".
The Architect should have this hatched on the Stamped Approved Plans

If no one wants to give you this information, tell the Architect / Client you are forced to apply the most restrictive Classification and Division, then turn in your Change Order for Class 1 Div 1 wiring upgrades!
That should get some attention wink

Scott

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!