Sean, I'll parrot everyone else with needing to CYA with thorough documentation but do want to go against the grain a bit and opine that any level of sprinkler protection is going to add to the life-safety of the dwelling even if we all know it won't actually control a Li-Ion battery undergoing thermal runaway.
Since the primary goal of 13D is to provide time for the occupants to escape the house, having waterspray cooling the walls and contents around the car, and hopefully activating an audible alarm, will provide more protection than they currently have. Now for the actual performance of the system, there is nothing stopping you from just following NFPA-13D because the standard does not differentiate design criteria for specific hazards. However, since we know that this hazard is significant, then you might want to consider some ways to improve the performance of the system while staying within the overall scope of 13D. 1: Perhaps you'd want to recommend providing a tank and pump system that can provide significantly more gpm than your current 3/4" water line. 2: How many sprinklers will the entire garage need? Since we know the discharge of two sprinklers won't overcome the heat output of the fire, you'd might want to consider what all the heads in the compartment activating would do to your water supply duration if you go with the tank. You might want to provide extra stored water to make sure you have your 10-minute duration in this scenario. 3: In the same vein, you'd probably want to count the entire compartment as your design area to ensure all the heads can all meet their discharge pressure requirements while flowing simultaneously. 4: Half joking, but see if you can provide a relay from the flow switch that opens the garage door so that the fire dept can have immediate access to the car when they arrive. (On second thought, this might not actually be a good idea if it messes with your sprinkler head spray patterns and/or allows the fire to spread up the outside of the house?) I'll be the first to admit that it is easy to go down the storage hazard protection rabbit hole, especially if you do a lot of design work in that niche, even though the goals of the two standards are significantly different. Hope this helps! Eric Rieve Rieve Fire Protection -----Original Message----- From: Sean Lockyer <slock...@aitlifesafety.com> Sent: Wednesday, July 5, 2023 1:09 PM To: sprinklerforum@lists.firesprinkler.org Subject: [Sprinklerforum] Optional sprinkler protection in garage without sprinklers elsewhere I have an interesting situation here: A homeowner has an electric car and an electric car charger in her garage. However, the house is not sprinkled and she is asking to just sprinkle the garage only. The AHJ has even pre-approved just protecting the garage only and not the entire residence. No problem, right ? Well, I don't know, TBH. There is a 3/4" water line that COULD feed these 4 or 5 heads, but under what code reference would you apply here ? Since this would have been a 13D system to begin with, could you have just put in a few concealed residential heads and connected to the 3/4" water line ? All the AHJ has asked for is to draw it up, permit it, and provide a bell for notification in case of a fire. Other than that, details are sketchy until they can review it. Some AHJ's would go way over-the-top and ask for a separate line, extra hazard protection, etc.... and another one I could see wanting a special hazard system. What does everyone else here think about this ? Everyone at the office believes I am over-thinking it but I believe that over-thinking something is better than not putting enough thought into something when the alternative could cause more problems down the road. Thanks, Sean AIT Life Safety _________________________________________________________ SprinklerForum mailing list: https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org To unsubscribe send an email to sprinklerforum-le...@lists.firesprinkler.org _________________________________________________________ SprinklerForum mailing list: https://lists.firesprinkler.org/list/sprinklerforum.lists.firesprinkler.org To unsubscribe send an email to sprinklerforum-le...@lists.firesprinkler.org
