Wireless (Wi-Fi) Communications

[jlewis77]

I am trying to find out the extent of wireless communications on production platforms and oil and gas processing facilities. This communication would be used for process data transmission. 1) Do you know of such installations, 2) Do you know of such installations in intrinsically safe areas of the facility.

 

[JohnFortier]

It's been quite a few years since I was involved in telecomms on oil platforms. That was inthe North Sea, usually under BASEEFA/CENELEC regualtions as far as intrinsic safety was concerned.

I'm fully aware of the time and trouble it takes on a platform to retrofit any communications system, so using wi-fi must seem very attractive. However, I hope you're bearing a few points in mind:

Like any radio system, wi-fi is subject to fades caused by reflections and refractions. On a rig, my experience was that the higher the frequency, the more prone the signal was to such fades. One of the main causes of these fades was the people moving around; the signal would be reflected and or attenuated, usually both, by the nice conducting human bodies that kept insisting on getting in the way. It didn't make for very reliable comms.

The other is that any platform is made up, for the most part, of isolated metallic compartments, and getting a signal into these can be a pig's bastard of a job.

So, my advice would be, before starting to rely on the wi-fi infrastructure, to carry out a series of very intensive tests on the signal strength and reliability, especially if it is to be used for process control, which, unless things have changed a lot over the last fifteen years, needs to be utterly reliable.

I don't know here your rig is located, but on the rigs in the North Sea, Lloyds inspectors had to pass on all telecomms systems before they could be used for life critical applications. Wi-fi isn't normally used for such applications and its intrinsic reliability may not be up to the requirement. I'd look into this very carefully.

Obviously, unless the equipment is mounted in an explosion proof container, or is modified to intrinsic safety, it can't be used in any place where an explosive atmosphere may occur. Since this is most parts of a rig except the accommodation module, you may find that the effort of installing a wi-fi system is actually greater than that of installing a standard, wireline or fibre system.

By the way, if you think you have problems, about 12 years ago I worked on the Saudi Strategic Storage System, storing huge quantities of processed petrochemicals underground. The installation, which included a lot of control and telecomms, had to be both intrinsically safe/explosion proof and EMP proof. Good fun!

I hope this didn't sound too pesimistic, but offshore telecomms are fraught with problems which never occur on the relative safety of dry land.

Regards

John