Sunday, February 12, 2012

On Elevators

Mad Jack, a fellow blogger, asked me recently about elevators, mainly do they ever fall and how do you get them unstuck.

I should have responded to his comment earlier, but me being the derelict blogger that I am, I let several days go by without responding. That and the lengthy answer made me decide to write a post, one primarily for those who do not deal with these issues very often, if at all.

This is not a lesson plan for dealing with elevator emergencies, my knowledge is narrow and old. There are many out there who deal with these daily and are far more proficient at mitigating them. This is more me telling about how I dealt with the ones in my district, back in the day.

As for as the "do they ever fall?" question, I am sure that it has happened, but so many things would have to go wrong in order for it to happen that it basically never does.

Most of our elevator problems consist of an elevator getting stuck between floors. When I say between floors, I mean that the elevator car is not wholly aligned with the hoist-way door. When this occurs, neither the elevator car door, nor the hoist-way door will open and the car will remain stopped. The occupants usually do not like this very much and will hit the alarm button or use the elevator car telephone if provided. Occasionally, a trapped occupant may be slightly claustrophobic and begin to panic. This is not a positive experience for anyone in the elevator car.

The reasons for the car stopping are many, but it usually is one of a few things. For us, probably the main reason for a stoppage is a "fart" in the computer that controls the elevator. These computers, as with any computer, occasionally decide to freeze up and the system comes to a halt. Many of them have a reset procedure that consists of hitting several buttons on the various circuit boards in the elevator control box.  Once reset, the system restores and the elevator continues on it's merry way. Sometimes, if the reset procedure is not known, power to the computer will be removed and it will reboot. The result is the same as resetting it.

Sometimes, a hoist-way door or even the car door will not close properly or not trip the appropriate switch, causing the system to stop. Rattling the hoist-way doors and having the occupants rattle the car door may correct the problem.

Older elevators have a mechanical inertia switch located on the cable drum at the top of the hoist-way. It's job is to detect if the car is moving too fast and shut the elevator down. It can easily be reset, restoring the system. One of the elevators at City Hall had a bad inertia switch, if people got a little froggy inside the elevator car, the inertia switch would trip and we would have to go up and reset it. We put up with it for a few years before the elevator was removed from service. A remodel of the other two elevators increased speed enough that the problem child was no longer needed. I don't know if it was ever restored.

My procedure in dealing with stuck elevators was to first make sure the RP had contacted an elevator tech and have them respond. Most reputable elevator maintenance companies will send someone immediately if someone is stuck. I like having them there, as occasionally they can resolve the issue more efficiently than we can. Having a tech there also usually causes a mechanical issue to be resolved immediately, reducing further responses.

Once we arrive, we locate the car and make contact with the occupants. This is accomplished by shouting through the hoist-way doors. Words of reassurance go a long way in keeping stuck occupants calm. While contact is made, some of the crew will rattle doors, often on their way to the elevator control box, usually in the basement or up in the attic, above the elevator. The second in officer goes to the lobby and tries the fire service control key, sometimes that will immediately recall the car to the lobby where the occupants will be let out.

If those things don't work, we will reset the control computer. That usually takes a few minutes, but often works.

If none of those work, it will then be necessary to pick the hoist-way door, then manually release the car door from the outside. There are special tools to do this, it is not that difficult. The hard part is remembering where the locking devices are and how to manipulate them. As you may see a particular elevator only once in your career, it helps if that info is in a pre-plan book. There isn't a high degree of standardization between elevator manufacturers, especially the older ones. Plus, elevators are modified during the course of their lives, things aren't always put back together the same way as before. Once the doors are opened, the occupants can be removed. Sometimes a ladder is needed if the car is not close to the hoist-way door.

If you have to pick the door to remove the occupants, IT IS IMPERATIVE  THAT POWER TO THE ELEVATOR IS SHUT DOWN FIRST! Better yet, lock it out of you can. The last thing anyone needs is for whatever problem to correct itself and  for the to car start moving while someone is half in or half out of it. Though rare, it has happened (or so I've been told)

Sometimes, the tech arrives quickly and resolves the issue for you. That is good. Sometimes, people feel the need to "force" the doors causing damage. This is not so good. I hear the jaws can really mess up a hoist-way door, so don't use them. Unless. of course, it's me stuck in the elevator and happy hour will be over in a few minutes. Then use dynamite if you have to.

Thanks for reading,
Schmoe

Like I said, there are A LOT of peeps that could tell you a lot more than me, this is just what we did at the big house, back in the day. Many of our problem children have been re-habbed or replaced since then,  

2 comments:

  1. Yeah, you're a derelict alright... :)

    Thanks for the post. I was stuck in an elevator once, and it was not a pleasant experience. I wasn't stuck for long as a security guard pushed the button to summon the elevator to the next floor above and it obliged him by descending to the ground floor.

    One building in Southfield, MI where I used to work had an elevator that fell about three floors into the basement. Several people were hurt, one with a broken arm. Another lady I knew personally was on an elevator in Toledo, Ohio that fell several floors. She hurt her back and went on permanent disability.

    I've always been a little curious about what the fire department would do about a stuck elevator - it kind of seems like police work to me, but then what do I know - right?

    Later!

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  2. New DOSH safety directive requires all passenger elevator fitted with these: 1. Elevator door locking device 2. Emergency Battery Operated Power Supply.

    ReplyDelete