Is there a KNOWLEDGABLE person here who can explain how a Y2k bug can shut down a refinery or cause a natural gas explosion? : LUSENET : TimeBomb 2000 (Y2000) : One Thread

Is there a KNOWLEDGABLE person here who can explain how a Y2k bug can shut down a refinery or cause a natural gas explosion? If there is such a person, I'd appreciate an explanation. Please provide an explanation with as much technical detail as would be in a Scientific American article. If embedded processors are used to control these processes, describe the process and exactly how the date is necessary for the process control. Readily obtainable references (on line or in a public library) are fine, but one of the Y2k "experts" such as Paula Gordon don't make it -- let's have someone who doesn't have an axe to grind either way.

Just the facts please.

-- Mikey2k (, January 21, 2000


I could - but I'm too tired. I'm going to bed.

-- X (X@X.X), January 21, 2000.

Not being a KNOWLEDGABLE person on this topic, all I can offer is what's on line. What's on line is a documented incident thats deals with a fuel line rupture instead of a natural gas line. But the information may be helpful regardless. One reason for having access to this information at all is due to the fact that innocent people were killed due to a pipeline rupture which is covered by NTSB. Otherwise, I wonder if we would ever have known anything useful at all.

If you don't want to go to the link which is provided below, here's an excerpt from the U.S. Dept. of Transportation Office of Pipeline Safety:

Background: During an Office of Pipeline Safety (OPS) investigation of a recent pipeline incident, OPS inspectors identified inadequate SCADA performance as an operational safety concern. Immediately prior to and during the incident, the SCADA system exhibited poor performance that inhibited the pipeline controllers from seeing and reacting to the development of an abnormal pipeline operation.

Preliminary review of the SCADA system indicates that the processor load (a measure of computer performance utilization) was at 65 to 70 percent during normal operations. Immediately prior to an upset condition occurring on the pipeline, the SCADA encountered an internal database error. The system attempted to reconcile the problem at the expense of other processing tasks. The database error, coupled with the increased data processing burden of the upset condition, hampered controller operations. In fact, key operator command functions were unable to be processed immediately prior to and during the abnormal operation. It is possible that post installation modifications may have hampered the system's ability to function appropriately.

The combination of the database error, the inadequate reserve capacity of the SCADA processor, and the unusually dynamic changes that occurred during the upset condition, appear to have combined and temporarily overburdened the SCADA computer system. This may have prevented the pipeline controllers from reacting and controlling the upset condition on their pipeline as promptly as would have been expected. For further information, contact Chris Hoidal, Director, OPS Western Region at 303-231-5701.

There segment above comes from:

They don't say exactly what the database error was. I seem to recall that just after the accident, operators were mentioning something about testing new software. Very soon, these statements were retracted for legal reasons.

There is much more info on this incident including audio files, photos, news reports, and more offical statements at:

-- warren blim (, January 21, 2000.

Simplistic explanation: An embedded chip (Chip A) is placed in a natural gas pipeline to monitor for gas pressure. When queried by the computer, the chip responds with the gas pressure. Another chip (Chip B) opens and closes a valve which allows the gas into this pipeline, which is a branch off of the main. Using this arrangement, the computer can balance pressures in gas pipelines by obtaining the pressure, then opening or closing valves of various branches to balance the pressures. An explosion ( resulting from a state of over pressurization of the pipeline) can occur if Chip A fails to accurately report the pressure or if Chip B fails to open or close the valve to regulate flow into the branch pipe. After rollover, when queried by the computer, some chips failed to report the pressure and would respond only with an error message. In earlier tests late last year, it was found that a chip such a B might respond to a computer command to open a valve but would not respond to a second computer command to reclose the valve, after rollover. This type of arrangement is also used in refineries to monitor pressures within pipelines. The chips are also used to monitor flow rates of oil with the pipelines, to calculate the number of gallons that have gone through the pipe, and to monitor temperatures.

-- Y2kObserver (, January 21, 2000.

PS: The date isn't really necessary for this type of scenerio, except that it is used by the computer to record the pressures at specific dates and times and when valves were opened/closed. Once the date/time function is built into the chip, it is there whether actually needed/used or not. Then after rollover, a certain unknown percentage of the embeddeds were found to fail, ie: stopped performing their intended function and either stopped functioning altogether or responded only with an error message.

-- Y2kObserver (, January 21, 2000.

PS: PS: Also, some tests of chips found that they functioned normally during January, but after January 31, 2000, the next date was found to be January 32, 2000. From that point on, a mismatch of dates would occur between the chip and the computer software, with no way to correct the date within the embedded. Thus, an error situation would develop at that point, where again the chip would either cease to function or report an error message upon being queried.

-- Y2kObserver (, January 21, 2000.

And you are excately right Mr. Y2kobsever, about January 32. Care to speculate on the leap year? (Or, for that matter what key The Fat Lady is going to sing in? Things may get as Confusis said " May we live in intersting times".


-- Shakey (in_a_bunker@forty.feet), January 21, 2000.

Dear Mikey2k ( :

all Shakey did is build some o them plants..... Probably not someone to listen to.

Night train

-- jes an ol footballer (nighttr@in.lane), January 21, 2000.

dear warren blim, the links you posted no longer carry the article, i assume sites have been updated since the accident. it is a good explanation of how computer problems can cause these serious problems but think we should mention that this accident occured in june, 1999 and not since the rollover. at first glance one may take it to be a y2k incident. (of course, as stated, if they were installing new software or something, it could be indirectly linked.)

-- boop (, January 21, 2000.

LOL, it's 1/21/2000 and we're still here at the "how".

-- Hokie (, January 21, 2000.

Warren, yours was the most credible sounding answer because you didn't try to make something up.

Y2kObserver, your explanation involves single-point failures and I'd have to wonder why we don't have these problems all the time due to sensor failures. Perhaps Shakey did build the plant.

And Shakey and Hokie, yeah shakey and hokie, that's the quality of your answers.

-- Mikey2k (, January 21, 2000.

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