Oil facilties fire protection questions

[jman1970]

I am a manager of a company and we have just been awarded a contract for the design and installation / revamping of fire protection / prevention systems for a major oil pipeline, loading facilities, and pump stations. My engineering department has been leaning toward the utilization of Ultrasonic Gas Detection systems. I am the GM of the company and far from an expert in this field, however, read an interesting article entitled, "Can The Petrochemical Industry Feel Safe with Traditional Gas Leak Detection?" by Martin T. Olsen available at

http://www.gassonic.com,

but would like to get some objective expert opinions to the pros and cons of overall fire protection systems in oil and gas installations to aid me in making a decision on which direction to go.

Will be very appreciative of any insight an expert may be able to provide in this area.

 

[DM2]

We've used the Gassonic leak detector for a project in the North Sea. The cost of the unit is about $15,000.00.

Initially I was skeptical that there would be false alarms due to background noise on the compressor platform we installed the equipment on. It's difficult to say from personal experience as I only say the equipment work under test conditions before the platform was in full operation.

We set the system up connected to a 4-20mA analog input to our Fire & Gas Panel. 4mA was equal to 56dB and 20mA was equal to 115dB (or something close to that, I'd have to go back and check). Both a low and high alarm level were time dependent (i.e. the Acoustic noise had to be present for a given time). I think the time was 15 or 30 seconds. We set the system up so that these values could be adjusted in the controller via the HMI and a password. The idea was that they needed to see how noise the platform would be during normal operation which we couldn't do at that time. These recommendations were provided by Gassonic (actually Martin Olsen directly...he's a real good guy to work with as is the company).

I haven't heard back from the user, who I do communicate from time to time with. They're using these in other areas of the platform.

You should know that the area coverage of these units is about a 15' diameter circuile below the sensor and 3' above the sensor.

The unit has a Noise generator for self test when I spoke with Martin about another project, they should be getting the Unit SIL rated shortly.

There is an published by the UK HSE department (HSE Offshore Technology Report - OTO 1999 079, "Offshore Hydrocarbon Releases Statistics, 1999") that documents the likely hood of detecting a gas leak on an open platform. Based on statistics from 1992 to 1999 the likely hood was 65%. The mandate to record such releases was as a result of the Piper Alpha platform.

There's also another publication by the UK HSE (
Research Report RR568, "Measurement of acoustic
spectra from liquid leaks") that offers further discussions on the use of these devices.

Hope this helps
Regards,
Dan M. Marr