JRW Posted October 2, 2020 Report Share Posted October 2, 2020 Hi All, I'm currently working in a warehouse space (approximately 7500 square feet) and am considering getting my own kiln for greater flexibility and faster/cheaper firings. The space has multiple individual studios with four walls but no ceilings - so that any gases/fumes will rise into the loft of the warehouse where there are ceiling fans that push interior air outside. The problem is, I won't be able to vent the kiln directly to the outdoors. The manager has told me that the space is "built code for artists, with an air exchange every 20 minutes", and apparently there have been kilns in the space before. From my research it looks like venting kilns is important not only for health reasons but also for good/reliable firings and preserving kiln components. My question is, would a downdraft venting system that pulls the fumes from the kiln but vents them into the larger atmosphere of the warehouse (but NOT outside) be safe? I would do firings overnight and not be near the kiln while it was firing, but it's possible other folks would be in their studios elsewhere in the building. (not many and not very likely, but some people may work late into the night/morning.) The manager seems to think it's fine, but he's not an expert, and I plan to consult with Skutt, but I'm not sure if they will be comfortable advising on this. Any thoughts? Thanks! Link to comment Share on other sites More sharing options...
liambesaw Posted October 2, 2020 Report Share Posted October 2, 2020 Kiln fumes also have a serious affect on metal, glass, acrylics and polymers. It may be dilute enough in that big of a space, but if other people have work stations in the immediate area, you could have a negative effect on their work. Something that comes to mind is the interaction between paints and acid on canvas and paper. Kilns release acid vapor that condenses into acid. It would be something that maybe you can work out with the owner, but something to mention. Gasses coming out of the kiln are hydrochloric, sulfuric and hydrofluoric (glass etching). If you do lustre firings you'll run into nitric acid as well. And then of course there's the oxide vapors like copper and chrome which condense outside of the kiln. All that scary stuff said, it's probably fine. Link to comment Share on other sites More sharing options...
Hulk Posted October 2, 2020 Report Share Posted October 2, 2020 You might run the duct from the downdraft vent straight up - as far as you can go (and still have it work well). If the air column turns out to be too much (cools too much), a helper/booster in line fan should sort that. Link to comment Share on other sites More sharing options...
neilestrick Posted October 2, 2020 Report Share Posted October 2, 2020 Vent it. Your kiln will last longer and it's the only way to be 100% sure it's safe. Every 20 minutes is only 3 changes per hour, which according what I can find is basically the minimum you should have for the most basic air quality. 'Built code for artists' likely doesn't include kilns or other systems that create fumes, but rather general air quality for people using paints and such. According to this website, room air in a factory with fumes should be exchanged 10-15 times per hour. And according to OSHA in a laboratory setting where fumes are an issue, "4-12 room air changes/hour is normally adequate general ventilation if local exhaust systems such as hoods are used as the primary method of control". HERE is another page that lists typical exchange rates for different types of settings. For commercial kitchens, factories, foundries, etc, they all start at 8 exchanges per hour, and still use spot extraction in addition. If you were to fire the kiln while someone is nearby, they'll be breathing the fumes, especially you, if you want to use your studio while it's firing. And like Liam said, all sorts of acids and whatnot that can affect other materials in the space. From a purely legal standpoint, I'm surprised that the manager is willing to open him/herself up to liability like that. Venting is simple, and only requires a 4" penetration to the exterior, through a wall or ceiling. Running it up to the ceiling fans will only work if they are powerful enough to deal with the volume of air coming from the vent and not let the polluted air fall back down or circulate. What is the current kiln situation? Are there other kilns in the space that you're currently using? How are they vented? Link to comment Share on other sites More sharing options...
JRW Posted October 2, 2020 Author Report Share Posted October 2, 2020 Thank you all for your feedback. Neil, to answer your question, this is a commercial studio space for artists of all kinds and there is only one studio that is wired for a kiln. There have been several artists who have used kilns in that particular space before me, I am told. No one has mentioned any issues with it. Currently I take my work to be fired elsewhere. I don’t think it will be possible to vent to the outside. There is no exterior wall close to or adjacent to this studio and I very much doubt the manager will let me drill a hole in the ceiling. It sounds like the major concern here is the health as well as work/materials of people close to where it is being vented. In terms of health concerns, if it dilutes overnight do you think it is an issue? I wouldn’t fire during the day or be in the studio when firing... Link to comment Share on other sites More sharing options...
JRW Posted October 2, 2020 Author Report Share Posted October 2, 2020 Also, regarding the air exchange comparisons: aren’t these other places you mentioned (Foundries, laboratories, commercial kitchens etc) typically in much smaller and more enclosed spaces with a lot more fumes and pollution? Do you think one kiln in a huge warehouse could pose much of a threat? It’s not sounding great but I’m curious what you think. Link to comment Share on other sites More sharing options...
Bill Kielb Posted October 2, 2020 Report Share Posted October 2, 2020 43 minutes ago, JRW said: It sounds like the major concern here is the health as well as work/materials of people close to where it is being vented. In terms of health concerns, if it dilutes overnight do you think it is an issue? I wouldn’t fire during the day or be in the studio when firing................... Do you think one kiln in a huge warehouse could pose much of a threat? It’s not sounding great but I’m curious what you think. None of this adds up number wise actually. 7500 sf, maybe 30 feet tall (loft) tells me 225000 cubic feet or 675000 cubic feet every hour which is 11250 cubic feet per minute, which even in the Midwest would require about 30 tons of AC just to offset the air leaving before cooling the space one degree. If there are recirculating fans hanging from the ceiling, they recirculate air and don’t send it outside. A common technique to recirculate in tall spaces to even out the air temperature. Walls 10 feet high With no ceilings are to make this single zone without need for multiple returns and allows the sprinkler system at the ceiling to cover the space saving the cost of dropping them into the various ceilings. All things done to reduce first cost of building the studio, not necessarily for the health of the artists. Not providing easy access to Local exhaust is a mistake IMO. Artists will have a need for local exhaust for many reasons. Not having anticipated this seems marginally planned. Single zone means shared heating and Ac air and recirculating fans almost guarantee to mix all the fumes and distribute them to everyone nicely. To be code as a studio, ventilation standards that apply are based on use and Potential People In the space with the people part being generally the most costly. IMO The kiln should be vented outdoors, it is the only for sure way. The kiln is warm and warm air rises but there is no guarantee that the components aren’t heavier than air. Carbon monoxide, propane and many other combinations of gases like to accumulate on the floor because they are heavier than air. As a person who currently consults in the design and energy use of spaces such as yours I would suggest venting this outdoors and leave the potential liability for code to the landlord / business owner. Link to comment Share on other sites More sharing options...
JRW Posted October 2, 2020 Author Report Share Posted October 2, 2020 Bill, thank you so much! This is very useful information. All of this is new to me so I'm trying to puzzle it out. Based on what in see in the warehouse it's hard to understand how there could be an air exchange of that volume, that frequently. And I was wondering about the heavier gases/components of the fumes. Link to comment Share on other sites More sharing options...
JRW Posted October 2, 2020 Author Report Share Posted October 2, 2020 By the way - there are no recirculating fans and there is no AC or heat in the building. There are fans built into the ceiling which I assume pump air outward. Link to comment Share on other sites More sharing options...
Bill Kielb Posted October 2, 2020 Report Share Posted October 2, 2020 14 minutes ago, JRW said: By the way - there are no recirculating fans and there is no AC or heat in the building there are fans built into the ceiling which I assume pump air outward. Where is this located approximately? Do they have winter and summer? When it’s 95 degrees outside at 75% humidity or 20 degrees at 20% humidity or even 50 degrees how do people work in the studio? How does paint dry? Maybe, ......................but I am not sure this sounds entirely correct. Venting the kiln outdoors is the appropriate solution regardless, worrying how this space works and if it does is not your responsibility. Link to comment Share on other sites More sharing options...
neilestrick Posted October 2, 2020 Report Share Posted October 2, 2020 I would be shocked if Skutt doesn't say venting is necessary. Too many variables and too much liability to say otherwise. Aside from the health and safety issues, it will extend the life of the elements and the metal parts of the kiln, improve firing evenness to some degree, and improve the look of your glazes. Link to comment Share on other sites More sharing options...
neilestrick Posted October 2, 2020 Report Share Posted October 2, 2020 11 hours ago, JRW said: Also, regarding the air exchange comparisons: aren’t these other places you mentioned (Foundries, laboratories, commercial kitchens etc) typically in much smaller and more enclosed spaces with a lot more fumes and pollution? Do you think one kiln in a huge warehouse could pose much of a threat? It’s not sounding great but I’m curious what you think. Not necessarily. Factory space can be huge, as can commercial kitchens and bakeries (think food production, not just restaurant kitchens). 7,500 square feet isn't really that big. A school gym with a single basketball court would be that size, and no school would put a kiln in there without venting it. The CNC business down the row from my shop has more space than that. The issue here is that the HVAC numbers the manager is telling you probably don't include a kiln or other processes that create fumes for hours on end, because if he really knew about kilns they would have included a dedicated venting method just for it. Nobody having issues with it in the past doesn't equate to safety and certainly doesn't absolve you or the building owner of any liability. Any process that is creating hazardous fumes should have dedicated venting, especially if there are other people involved. If it was just you in the space, then I would say venting is best but ultimately it's your choice because you're the only one being affected. But as it stands you've got a responsibility to the other people in the building. Does it really not have heat or AC? Link to comment Share on other sites More sharing options...
JRW Posted October 2, 2020 Author Report Share Posted October 2, 2020 I live in Berkeley, CA, which is a very temperate/Mediterranean climate with relatively mild summers and winters. The building gets hotter during summers and colder in winters, but it's manageable for people. (I have yet to be there for a winter). I did call Skutt and to my surprise, they said it's fine to vent it into the building. But I'm taking into consideration everything that you've said and will have a conversation with the manager. I really appreciate all the info everyone has provided! Link to comment Share on other sites More sharing options...
Bill Kielb Posted October 2, 2020 Report Share Posted October 2, 2020 38 minutes ago, JRW said: (I have yet to be there for a winter). Nice weather, winter might be a bit uncomfortable with no heat though. Link to comment Share on other sites More sharing options...
neilestrick Posted October 2, 2020 Report Share Posted October 2, 2020 1 hour ago, JRW said: I did call Skutt and to my surprise, they said it's fine to vent it into the building. I'm super surprised to hear that. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.