for experts: Elevator slowing down

Good day to you all,
We have two elevators in our company, they're about 10 years old.
randomly and not frequently, when moving down the elevator suddenly switches to a very slow speed and remains like that until reaching its targeted floor.
Thanks for your prompt reply.
Kind Regards.
Nick.

There could be a number of things that could cause this. Have you called a elevator company to look at this issue?

I agree with ABE, there is a veriety of thing that could cause this. You will need to bring in your elevator service provider. If this has been going on for a while and you have had several visit by your current company, You should speak to them and let them know this needs to be corrected.

If you don't have a elevator service company currently, post your City and State. We may know someone in your are.