Wood stove in an old commercial building

[Paolocito50]

Hi, and thanks for accepting me into the hearth.com family.

I'm helping restore an 1872 water-powered flour mill called the Butte Creek Mill in Eagle Point, Oregon that was damaged by fire in 2015. The retail outlet for the mill (it's known as the Country Store) has always been heated by a very old wood stove, and the store survived the fire with only smoke damage. I'm trying to find out what regulations we need to comply with so we can continue to use that stove rather than having to buy a new one.
All the regulations I can find only appear to apply to residential applications.

Questions:
1. Can we continue to use the old stove?
2. If I build a 4" thick brick hearth on top of cement board and a brick backer (with appropriate rear spacing for air flow) is that acceptable?
3. Does the brick backer have to extend all the way to the ceiling, or only to the top of the stove?

Thanks in advance for any help you can give.

 

[begreen]

The old stove will need 36" clearances in all directions unless the nearest wall(s) are shielded with an nfpa211 wall shield. 4" brick will afford a 50% clearance reduction. If there is a ventilated, 1" airspace behind the brick then it affords a 66% clearance reduction to 12". The wall shield must be open at the bottom and top at least an inch to allow unrestricted airflow behind it. Brick is not the only option for the wall shield, metal or cement board will also work. Old tin ceiling on a cement board backer can look good in the right setting.

A 4" thick brick hearth with cement board underneath should be sufficient.

The venting for the stove is equally important both for proper draft, clearances and safety.