Why drains are in elevator pits?

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A heated debate is raging about why the new elevator code requires drain or sump pump in the elevator pit. Is it to drain ground water? Is it to drain fire sprinkler system water to keep elevator running for fire department? Is it to allow draining of leaking hydraulic fluid?

I ask because various solutions may not work depending on the reason the ASME elevator code is requiring it. One solution is a sump pump to an indirect waste. Another is a 100 gallon tank UG with gravity drain and alarm to alert someone to empty. A third is to have alarm to drain pump from a connection outside the pit. Does anybody know the real reason?

thanks for any assistance with this.

-- Bill Cowdell (wcowdell@uci.edu), April 21, 2000


Drains (or sump pumps) are required in every pit to prevent accumulation of water, whether ground water, water from fire sprinklers or any other source.

The direct connection to sewers is prohibited to prevent entrance of sewer gases.

The method of complying with these requirements is a non elevator matter and beyond the scope of the Elevator Code. The methods you mention would seem to be possible alternatives.

-- John Brannon (akaelevman@AOL.com), April 23, 2000.

Thanks John for your response. As a mechanical engineer, I have always thought the elevator pit drain was only for ground water. What happens when fire sprinkler water fills the pit. Would that stop of the operation of the elevator? But if a fire sprinkler head is discharging then no one should be using the elevator anyway. We water proof our pits and provide a foundation drain to keep water out of the pit. That is why our preference is a 100 gallon tank with gravity drain. If a sprinkler head goes off the tank could fill up. There is not way to size a tank to handle a fire sprinkler discharge.

The third suggestion that I listed does not drain the pit until someone comes with a pump. This is what the City of Irvine recommends for this application.

While the elevator code does not address how to address the drainage of the pit it sured would be nice if they explain what the goal is. Just to drain ground water or a spill in the building is fine, but to drain the pit if a fire sprinkler head goes off needs clarification.

Can you suggest a source for additional information on this matter?

Thanks again for your comment and assistance.

-- Bill Cowdell (wcowdell@uci.edu), April 24, 2000.

Bill, the idea of the drain is so that water from thre sprinkler DOESN'T fill the pit.

There is no requirement to alter the operation of the elevator if the pit does fill up with water (from the lack of a drain, a clogged one, whatever)

The rules are made by the members of the ASME Elevator and Escalator Committee.

Interaction with the Committee is available by requesting interpretations, proposing revisions, etc.

You may write to the following:

Secretary, A17 Main Committee The American Society of Mechanical Engineers United Engineering Center 345 East 47th Street New York, NY 10017

-- John Brannon (akaelevman@AOL.com), April 24, 2000.

Pit sumps

Bill: It may not be apparent during construction but in many if not most cases the elevator pit is the lowest elevation in any building. In many jobs the pit slab is poured and seveal days later(or weeks) the walls are poured. If the connecting area between the walls and slab have not been washed off before the walls are poured you have a layer of dust and debris that ground water will seep through. Any water problems in the building will migrate to the elevator pit. If the elevator has "outside" entrances that are washed down with water or underground parking, more water. As any serviceman with any experience can attest there is nothing worse (or more unsafe) than working in a wet pit. In a dry area (low ground water and all inside entrances) it is acceptable to fill the sump with medium sized rocks or cover with grating. If water is a problem a sump pump connected to the clean (storm) sewer system will work. Since most sump systems have "backflow" prevention they could be hooked to the sanitary system and are in many cases. Hope this helps, Fred

-- Fred Baltes (Elman101@aol.com), May 08, 2000.

Sump pump..

I have seen an overflowing slopsink or toiletbowl in a highrise building soak the cab and fill the pit in no time if the sump pump is not working and no one realizes there is a flood...Now working on the beach, with all hatch doors exposed to the weather, everytime there is a storm with rain falling horizontally I can be guaranteed to have elevators shutdown all over and pits full of water...

-- Joe..M (SuzieMcL@aol.com), October 15, 2000.

One possible solution could be found at: www.seewaterinc.com

-- Ronald D MacDonald (seewaterinc@yahoo.com), October 14, 2003.

Once had a toilet waste pipe leak. It was on a floor under construction the plumber didn't properly install the pipe. Originally we thought the construction workers were urinating in the shaft, until the leak got worse and all the elevators stopped working. Had to clean the entire shaft and replace most of the sheetrock. Anyway thankfully we didn't need a drain in the pit, but that would be another reason for one.

-- James Masler (masler@aol.com), March 01, 2004.

I have a related question. I work at an engineering firm in San Diego, and California code says that the sump pump can not be located in the elevator shaft, or below it in some kind of pit. This poses a problem for me, because most pumps I have found for draining elevators are submersible. Do any of you know what kind of elevator pump is typically used in California, and how it is configured? Thanks a ton.


-- Taylor Semingson (tsemings@ucsd.edu), March 10, 2005.

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