CODE MADE EASY W R I TT E N BY S H AW N B E R G E R O N
n the Winter and Spring issues we made our way through how codes work, provided information about your occupancy and discussed how and where your new distillery can be built. In the Spring edition we left off in the milling room, trying to keep you from blowing up, with interesting facts about explosion-proof fans. Let’s bring the removal of explosive grain dusts from that milling room to conclusion so we can move farther into your wonderful new home. When we parted I mentioned the need to replace the air that is exhausted when your crazy-cool-explosion-proof fan is removing dust from the milling room and yes, seriously, replacing that air is something you have to do. The walls of your mill room will not suck inward nor will the ceiling collapse if you don’t, but the fan won’t work as it should and the dust won’t go away. What you are looking for is “makeup” air and here is what you need to do to provide it: Look closely at your exhaust fan, or almost any fan for that matter, and you will find a label attached that will tell you its capacity in CFM which stands for “cubic feet per minute,” the volume of air your fan can move. Now let’s say your
spacious new mill room is 20 feet wide by 16 feet deep and 10 feet tall. Take a trip down memory lane to sophomore geometry to calculate the volume of that room and you will arrive at 3,200 cubic feet, perfect high-school math. Coincidentally the label on your new 18 inch fan tells you it is rated at 3,200 CFM so theoretically this means that in one minute your fan can exhaust all the air from your mill room, carrying those booger-forming particles outdoors. Now if we remove that air and the particulate grain dust that is suspended in it, how do we replace it? The easiest way is to allow the make-up air to infiltrate your fire-resistant room in some manner but when you do there are a few things to consider:
»» How does this air infiltrate my
otherwise quite tight mill room?
»» Where is it coming from and might that be a problem?
»» How much air do I need to provide? »» If it’s coming from outdoors, are there other considerations?
We need to get the make-up air into your otherwise closed room and the easiest and least expensive way to do this is to install a passive supply-air louver.
PASSIVE SUPPLY-AIR LOUVER Passive, you say? Well, there are different types of louvers, and passive louvers just sit there and allow air to move through. If your louver is mounted on the exterior wall you need to be sure it is adequately far from the exhaust fan, otherwise the fan’s exhaust plume is going to develop a lovely circular pattern where the grain dust goes out and then comes back in…you don’t want that. Also, you need to be sure the louver is adequately far away from things like a vented gas meter or the exhaust from your water heater as you do not want carbon monoxide or propane wafting into your mill room along with what should be a supply of clean make-up air. You also need to consider if the exterior wall is fire-rated (remember the type of construction from the Spring edition?) because if it is, you are going to have to install a fire-rated louver with an appropriate fire rating. Louver details — yet another topic that is so cool you will use it to impress your friends as they sip your latest creation. A passive louver is a louver of the simplest form. Really, it’s a hole through the wall, albeit a hole that you’ve carefully thought about. You will begin with louver