The only fire risk will be if we locate the oven too close to combustable surfaces. Keep 6 feet away from any walls. Wall should be 5/8 drywall or metal, not wood. The oven radiates a lot of heat when in opperation.We should have a waiver of liability drawn up that all the volunteers should sign off on, acknowledging that the volunteers participate in the project at their own risk and hold harmless the ETF and other volunteers from liability in case of injury. AS unpaid volunteers, workmans comp won't be an issue.Even so, I think we will need some liability insurance. I would think that the fire policy of the ETF could have a rider for the rebuilding opperation attached.
We would need to add a ventilation system to the work area. As hot as those ovens will get, and with the flue gasses, this is an important consideration. We will also need to draw in fresh air for the work area while the ovens are running. The main gas shutoff and electrical panel will need to be accessible. I think the main gas trunk line may be sufficient for the ovens. We need to check with Scotty to see if the ovens need high velocity gas, or if what the museum has is sufficient. We also need to confirm whether the ovens are set up for natural or propane.
I am pretty sure that Scottys gas feed is a standard low pressure line. As I recall it is pretty good size. 1.25" or 1.5"You are correct about the heat radiated into the work area by the oven. As for the flue, the oven has a power draft flue, about 5" as I recall. You don't want to be drawing large amounts of heated air out of the oven, because cold drafts from the makeup air hitting the hot crt's can cause tubes to self destruct from the thermal shock.
You might be able to get some parts like guns from ChinaYou could carry "popular" tubes to generate income like 12AX7.You do not have to make them. there may be government contracts that require CRTs. Investigate "non profit" status for start-up.Network on "facebook" or elsewhere to talk to those who have worked in this business around the country.Look into getting land or a building donated.