Most clean rooms have HEPA filter ceilings with air flow from ceiling to floor level return, Depending upon class of clean room air changes per hour can range from 10 air changes to 120 air changes per hour and even greater as required. Response time is very important and the use of EC sprinklers could result is a serious delay in sprinkler head activation because the heat plum is being driven down to the floor return air inlets. Also the rooms are pressurized and the concealed heads might be gasket "clean room" concealed sprinklers. Make sure the concealed sprinkler plates can drop from the head, sometime the pressurization is high enough to prevent the concealed head's cover plate from dropping.
Have a fire safe day! Jim Jim Davidson Davidson Associates Fire Protection * Medical Gas * Code Consulting 302-994-9500 Fax:302-234-1781 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Cahill, Christopher Sent: Tuesday, April 03, 2012 10:01 AM To: [email protected] Subject: RE: Clean Room Protection Yep, follow the EOR's design. Doesn't matter if there are other ways to solve the problem. Options within 13 are not intended to provide equivalent performance. EOR has provided the minimum level of performance and in this case it appears to be response time is a key factor in his/her design. If it's design build without an EOR then do what you want that follows Code. Be thankful the EOR provided the rationale, wasn't required, but certainly is polite. Chris Cahill, PE* Senior Fire Protection Engineer, Aviation & Facilities Group Burns & McDonnell 8201 Norman Center Drive Bloomington, MN 55437 Phone: 952.656.3652 Fax: 952.229.2923 [email protected] www.burnsmcd.com Proud to be one of FORTUNE's 100 Best Companies to Work For *Registered in: MN -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of John O'Connor Sent: Tuesday, April 03, 2012 8:19 AM To: [email protected] Subject: Clean Room Protection I have an interesting issue concerning Clean Room sprinkler design: Facts: Clean Room, 200' x 100', with 10' CH. Engineers showing 28 rows of 7 sprinklers, (concealed K5.6) spaced at 14.28' x 6.67'. Question: Can this space be protected by EC concealed K11.2 heads spaced at 14.28' x 13.33' (look at the Viking VK538) OH sprinkler? I did not want to exceed the 16' dimension in any direction, forcing an 18'x18' design density or worse. Is a .20 design density an ordinary hazard risk even if the area is to be 3,000 SF? Can EC heads be used in this instance? Next Question: Engineers are very concerned over response time. Has response time been compromised at 14.28' x 13.33' spacing when the long dimension is still equal or less than 14.28' as originally specified? Is it a fair argument when diagonals are brought into the conversation where the center point of a rectangle of 4 AS spaced at 14.28'x13.33' is 9.77' to the closest head, compared to that of a rectangle spaced at 14.28'x6.67' being 7.88' from the closest head, and therefore compromising response time. Heretofore this industry has always used perpendiculars to walls and perpendiculars to adjacent heads when calculating spacing, etc. Otherwise we begin to space heads to corners of rooms instead of right angles to walls. The engineers argue that 7.88' extended to 9.77' is proof of extending response time in my design spacing. I argue that I have not exceeded his original long dimension of 14.28'. The Clean Room is for auto-parts manufacturing, product being inverters for the electric auto industry. Any experience out there in similar situations? Thanks for your input. John O'Connor National Fire Sprinklers, Inc. Nashville TN -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20120403/d46f3d35/attachment.html> -------------- next part -------------- A non-text attachment was scrubbed... Name: image001.gif Type: image/gif Size: 569 bytes Desc: not available URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20120403/d46f3d35/attachment.gif> _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
