I typically would NOT advice a sprinkler at a top of an elevator shaft, but I see what is for me, far too many going in anyway.
With a sprinkler at the top of an elevator shaft typically we would need: a smoke detector to initiate recall of elevator before shunt-trip a heat detector to initiate shunt-trip power drop Then after that gauntlet of consequences that looks good on paper I suppose, your sprinkler activates. I would like to hear from the forum the frequency with which we know that smoke detectors at the top of an elevator shaft are inspected, let alone replaced? Sometimes the smokes are installed center of shaft, so some lucky maintenance guy gets to hang his body out over floors of clear air space... scares most of the ITM people away. Sometimes the designers put a note to install the detector near a wall of the shaft (but not too near the wall for fear of the smoke flow dead zone...which in this case is all but splitting hairs). How many fires occur in elevators? Elevators are one of the safest forms of vertical transportation going... And even if a fire did occur in the elevator shaft/car, most modern elevator cars are non-combustible or limited combustible if they comply with ASTM A17.1 or EN 81-72 or equivalent And even if the contents of the freight elevator did ignite, it is in a 1- or 2-hour fire rated elevator shaft. Is there enough fuel in that freight elevator to burn for even 45 minutes? I would apply a risk based judgment upon the elevator-car, elevator shaft fire scenario, and factor in the consequences of installing sprinklers (and all the recall/shut-trip detection that becomes impaired within a few years). What if the sprinkler goes off and there is someone in the freight car. Now we have an entirely new set of issues that come into play: what will happen to the elevator controls after they are soaked with water? the emergency and fail-safe brake mechanisms should work despite the water from the sprinkler, but not as reliably as the ruggedized 'fire service access elevators' . And the 'fire service access' qualified elevators are another league of expense and effort I would just say 'No" to sprinklers at the top of elevators shafts, if given any freedom in the decision. I don't think many lawyers or building owners have enough design details at their fingertips to realize they could take the designer to court if water from an elevator-shaft-top sprinkler causes elevator damage, but if they did, they could. Sometimes simpler is better. I am all in, for sprinklers. I will put sprinklers over most servers and electrical gear 9 out 10 instances. But I won't put a sprinkler at the top of an non-combustible elevator shaft in 99 out of a 100 instances. Scot Deal Excelsior Risk and Fire Engineering gms: +420 606 981 266 GMT + 1
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