I have been reading various past posts and seen a lot of questions about exhaust and ventilation for the studio. While I am not an engineer I have had a little experience in the area of ventilation. OSHA has a whole list of requirements for ventilation and exhaust. Just to say that one has a squirrel cage fan does not even begin to address the matter of adequate air movement. Fan size is based on cubic feet per minuet(CFM) and friction loss in the duct work connected to that fan. Fans range in CFM from 20 to 2,500 or more so just to say I have a squirrel cage does not solve the problem. There are problems of what is being exhausted, acid fumes, cotton fibers, abrasive material. flammable gases, etc. You also will want to have more exhaust from the studio then you are supplying to it. In other word the studio must be negative pressure to the rest of the house unless it is a stand alone from the house. You always want to be drawing air from the rest of the house to the studio even when it isn't occupied. I would recommend a fan that has a motor out of the air stream for exhaust over soldering stations and buffing stations. For exhaust at buffing station a filter is necessary to prevent cotton fiber from the wheels being sucked into the duct and attaching to the fan. Soldering stations should have the fan within about 12" of the soldering brick for a good capture of the fumes. The buffing station fan can be interlocked with the buffing unit, the soldering station fan can have it's own switch and now to the general room exhaust. General room exhaust can be provided by a bathroom type ceiling fan. This is the fan that will help keep you studio negative to the rest of the house. One way to check if you studio is negative to the rest of the house is to close the studio door and with the house air conditions unit running, light a candle and on the outside of the door at the floor where there is a space, blow the candle out and see which way the smoke goes. If it drawn into the room your studio is negative to the rest of the house. If it is drawn out towards the rest of the house the studio is positive the rest of the house and needs more exhaust taken out of the studio. If you have any doubts as to what to do about exhaust please consult a licensed HVAC contractor or registered engineer.

Hello, I have read your post about ventilation and am wondering... where do you get the proper ventilation for the Studio. I am teaching at a community college, and they said they can put in a better ventilation if I can find some information. I searched under ventilation, but I only could find the vent for kitchens etc. I am looking for one for the vent for the kiln for lost wax casting.  At this point, I do not have a sure budget... any options out there?

In my former life before disability and retirement I was a Senior HVAC Designer. My best suggestion for a situation like you are in where student safety is concerned is to have someone in administration contact a consulting mechanical engineer. This is a person registered by the state to design the appropriate ventilation system for the studio, help in the bid process and help secure the necessary building permits. They will also provide all necessary code review for upgrading fire protection for the area as necessary. When you are involved with student safety things spiral out into the realm of big dollars fast but if things are not handled properly litigation is sure to follow from some parent if their child develops a problem. Just wondering, where are you located?