Firestopping Soda Lines-
This blog series is going to highlight some issues we have seen on projects that are easily overlooked if you are moving too fast, or if you are new in the game. It is our hope that by sharing these things with you and your team that you can avoid the mistakes. If you have any questions let us know. Especially if you have suggestions for supporting the rest of the people out there who want to do firestop right, then please share your ideas. Thanks for taking the time to learn.
If you are on a project such as a high-rise office or maybe a hotel that will have a bar or restaurant, then there is a good chance you will have soda lines in your project and they likely won’t get installed until towards the end. The conduits look like any electrical conduit so it’s easy to understand how someone inexperienced would allow this conduit to be firestopped with a standard detail that allows for steel, cast iron, electrical conduit as the listed type of metallic penetrating items. This would be a mistake. The fire dynamics are going to be different for metal than they will be fore steel and there is a chance that the firestop requirements will be different as well. If they are different, then the protection method could be different as well.
Then there is the liability. If you firestop it with a detail for steel and something goes wrong, then you are potentially liable for this mistake if you installed this or supervised the installation in any way.
Is there a difference, really?
YES, there is a difference between these two metals. Consider this. Melting point of steel is 2750F. Melting point of aluminum is 1221F. If you have been following this blog, then you may remember the “time temperature curve” (see below). This shows the temperature inside the furnace, for example at the 10-minute mark the temperature inside the furnace will be 1300F.
While I have not witnessed a test with aluminium pipe, I have seen photos and videos of the aluminum transoms and mullions of exterior facades and I have seen them drooping and deformed.
Is it really going to be firestopped that differently?
Here is a detail that allows a max 8” diameter aluminum pipe but it requires a minimum annular space of ½” and it needs a full inch of sealant. A typical steel detail would only need ½” or in some cases ¼” of sealant and would allow the pipe to touch the edge of the opening. http://productspec.ul.com/document.php?id=XHEZ.C-AJ-1342 or this one that allows a 10” aluminum pipe but requires wrap strip at the top and bottom of a floor assembly. If it’s a smaller pipe the parameters are a bit more familiar. These two details and the differences between the standard metal pipes you are likely familiar with should serve as a reminder to look at these details closer if they are on your project. http://productspec.ul.com/document.php?id=XHEZ.C-AJ-1112
How do I tell the difference?
First thing to do is to ask the question. The vendor installing the bar or restaurant equipment would be the first place I would go.
Second thing is to touch a magnet to the pipe. If you wonder whether or not it’s steel, a magnet will tell you. It won’t be attracted to aluminum, so it won’t stick to it. But be careful because this is not a guarantee that you are dealing with aluminum, because magnets may not stick to stainless steel. So, this brings you back to asking questions of the right people on the team.
Third thing to do is to keep your eyes open. You can see in the photo that its clearly marked on the floor SODA. After today, that should be a red flag for you to stop and ask questions before anyone firestops this.
If all you remember, is to ask questions whenever there is a restaurant or bar, then the time we took to write this was well spent. If you have any questions don’t hesitate to contact us. We are happy to help if we are able.