Confidence interval

I need help to determine the confidence interval of a failure rate. The problem is as follows.

I have a number of pieces of the same equipment installed in difference places. Next is an overview

16 pieces with total number of operating hours of 704,640
12 with 317,952
6 with 685,008
24 with 582,912

Total operating hours is 2,290,512.

For these 2M operating hours 14 pieces of equipment have failed and been replaced.

How can I calculate the failure rate and its confidence interval?