Elevators and sprinklers
By Samuel S. Dannaway, PE,
President, S.S. Dannaway Associates, Inc., Honolulu
Oh, how I long for the simpler days of years past; especially the days when it was not necessary to sprinkler elevator hoistways and elevator machine rooms. Actually, I did not want to get into the pros and cons of providing sprinkler protection for these areas this month. I will use this month’s column to look at the code and standard requirements and some of the history behind it. Perhaps there have actually been fire incidents that revealed how correct it is to sprinkler these areas. I would be very interested in your emails about elevator hoistway/machine room fire incidents.
So, what’s the big deal? The big deal comes from the provisions contained in ASME A17.1, Safety Code for Elevators and Escalators. The 2007 edition contains the following provision. Paragraph 18.104.22.168.2 states:
“22.214.171.124.2 In jurisdictions not enforcing the NBCC (National Building Code of Canada), where elevator equipment is located or its enclosure is configured such that application of water from sprinklers could cause unsafe elevator operation, means shall be provided to automatically disconnect the main line power supply to the affected elevator and any other power supplies used to move the elevator upon or prior to the application of water. (a) This means shall be independent of the elevator control and shall not be self-resetting. (b) Heat detectors and sprinkler flow switches used to initiate main line elevator power shutdown shall comply with the requirements of NFPA 72. (c) The activation of sprinklers outside of such locations shall not disconnect the main line elevator power supply. See also 126.96.36.199.6.”
As a result, we have been faced with as many different ways to accomplish this elevator power shutdown as there are authorities having jurisdiction (at least those AHJs not using the NBCC) and elevator inspectors. In my view, it has been an expensive and complicated undertaking. How did we get into this mess?
Let’s float back in time, exactly one day after the simpler times ended many years ago. A plan checker in Acme, Idaho, (or was it Frostbite Falls, Minnesota?) was reviewing a fire sprinkler submittal and said, “Hey, these spaces here on the drawing do not have sprinklers, and since those spaces do not have sprinklers, this building does not qualify for all the great advantages given to those that are 100% fully and completely sprinklered.” So, after the hoistways and elevator machine room were sprinklered with simple extensions from the wet pipe system, the elevator inspector comes in and says, “Hey, no can do! You must meet this here requirement in ASME A17.1 if you want to put water in your elevators.” The rest is history.
What was the justification for the plan reviewer’s determination? I went back as far as the 1994 edition of NFPA 13. I will try to find the first appearance of this language and report back next month. This is important, because Frostbite Falls may still be using the 1896 edition.
In the 1994 edition of NFPA 13, the requirements for elevators contain some interesting language. Paragraph 4-13.5.1 requires sprinklers at the bottom of hoistways. There is an important exception, indicating that sprinkler protection was not required if the elevator shaft was 1) enclosed, 2) noncombustible and 3) did not contain hydraulic fluid. Paragraph 4-15.5.3 requires a sprinkler at the top of the shaft but exempts this requirement if the hoistway was noncombustible and if the elevator car materials were in compliance with ASME A17.1, Safety Code for Elevators and Escalators, 1993 edition.
When it comes to elevator machine rooms, 4-15.5.2 simply states that “Automatic sprinklers in elevator machine rooms or at the tops of hoistways shall be of ordinary- or intermediate- temperature rating.” What is interesting is that this is not a requirement to install sprinklers in the machine room; it simply indicates what the sprinkler temperature rating should be if one chooses to sprinkler the elevator machine room.
The 1996, 1999, 2002 and 2007 editions of NFPA 13 have basically the same requirements. All reference various editions of ASME A17.1, Safety Code for Elevators and Escalators. The 2010 edition of NFPA 13 also contains these same basic provisions and added language to allow exemption of sprinkler protection where hoistway shafts were of limited combustible construction (i.e., gypsum wallboard) and a requirement to sprinkler top and bottom of hoistways if the steel elevator belts were coated with polyurethane or other combustible materials.
Though not yet officially published, the 2013 edition of NFPA 13 will maintain the same requirements and have additional provisions that prohibit sprinklers from elevator machine rooms and hoistways for elevators that meet the special design requirements of and are used for occupant evacuation or first responder use. Perhaps we are seeing the beginning of the end of the requirements for sprinklers in elevators and hoistways.
After reviewing these editions of NFPA 13, it is my conclusion that sprinklers are not required within elevator machine rooms by NFPA 13. Also, in most cases, the exceptions permit one to avoid sprinklers in hoistways complying with ASME A17.1. Please let them know in Frostbite Falls, Minnesota.
Next month we will look into elevators and sprinklers a little more.
Samuel S. Dannaway, PE, is a registered fire protection engineer and mechanical engineer with bachelor’s and master’s degrees from the University of Maryland Department of Fire Protection Engineering. He is past president and a Fellow of the Society of Fire Protection Engineers. He is president of S. S. Dannaway Associates Inc., a 15-person fire protection engineering firm with offices in Honolulu and Guam. He can be reached via email at SDannaway@ssdafire.com.