Print page

Home » Articles » Feedback

Voices: Feedback

Automation and Fukushima: Not So Fast

A Reader Responds to Liptak's Article on Fukushima Saying That We Have No Reason to Suspect That the Instruments Did Not Operate Correctly. Liptak Responds

It was with a profound sadness that I read this article, "Automation Could Have Saved Fukushima, March 2013, in Control.

It is full of technical inaccuracies. Operators, designers and instrumentation are blamed for the events at this power station.

The opening paragraph states that "had the level detectors operated correctly, and if the operators had flooded the reactors as soon as the earthquake was sensed, and if they had started venting of the hydrogen as soon as the rods were uncovered, the hydrogen explosions would have been prevented." This is just is not true.

Read Also: Help for Fukushima?

We have no reason to suspect that the instruments did not operate correctly. The environment in which they operated during the first stages of the accident (prior to the hydrogen explosions) should not have been significantly different from normal operating conditions. The operators would have been able to track the decrease in water level, and instrumentation signals to start emergency equipment should have been generated as designed. 

Unfortunately, because of a tsunami that was about 15 feet higher than the station was designed to handle, normal and emergency power supplies were flooded and not available; thus, the operators were unable at that point to put water into the reactor vessel.

If the operators had filled the vessel as soon as the earthquake was sensed (there would be no reason to do this because at that point emergency power was still available—and there was no reason to believe the resulting wave would be higher than design features), Fukushima still would not have been saved. The inevitable result of not having normal or emergency power sources would still have been the melting of the fuel, and the hydrogen explosions—perhaps delayed by several hours—still would have occurred.

To suggest that the operators should have vented the hydrogen as soon as the core was uncovered assumes that there would be significant amounts of hydrogen. BWRs by design can uncover some fuel without the fuel significantly overheating and producing hydrogen. The information I saw indicated that the venting was not so much the problem, but where the hydrogen was vented to. If normal or emergency power had been available the core would have remained covered and adequately cooled.

Read Also: Inside Fukushima and Preventing Future Disasters

There are several detailed articles published by the NRC and the American Nuclear Society which, if referenced, would have reduced the likelihood of publishing an article filled with technical errors, and which proposes a solution that would not have prevented or even mitigated the events of this tragedy.

Dan Daigler
dad@svcable,net

Béla Lipták responds:

Fukushima was much better designed than Chernobyl because the reactors had a negative void coefficient; they were protected by primary containment vessels (PCV); the PCVs were inerted and provided with wet wells; and scramming of the reactors was automatic. In contrast to Chernobyl, the operators made few mistakes, but the designers provided them with unreliable information (as I gave one example in connection with the useless level sensors) and, therefore, none of that made any difference. This accident still became a level 7 nuclear disaster, the second one in history.

Read Also: Automation Could Have Prevented Chernobyl

What the plant lacked was full automation that would have taken full advantage of the time window between the occurrence of the earthquake and the arrival of the tsunami (~ 44 minutes later) or of the time window between the earthquake and the starting of the meltdown (three to four hours).

Not enough automation?

The combined control room for Units 1 (left) and 2 (right) at Fukushima. Controls at the plant were mostly manual. Some of the valves these manual switches operated were not even provided with position detectors to tell the operators if the valve responded, and the control panel did not even have a graphic display to show which valve was open. When an annunciator window started flashing, the operator only knew that something was wrong, but it did not say what to do about it, nor did it actuate an automatic interlock.
Photo Credit: Ritsuo Yoshioka, President of Japan Functional Safety Laboratory.

The main and most important design deficiency (which even today is common to most operating nuclear power plants), was the inability of the plant to provide automatic and safe shutdown when both the external and internal electric power supplies simultaneously fail. In other words, the plant was neither provided with elevated water storage tanks (to take advantage of gravity to flood the reactors), nor with backup cooling water pumps driven by steam turbines, as steam energy was available.

Mr. Daigler is wrong, not only because level measurement was lost due to reference leg boil off, but also because the presence of hydrogen was not even measured. He is also wrong about the pressure relief system because it took almost a day for the operators to manually depressurize the PCV because the block valves isolating the rupture disks could not be opened. They had no hand-wheels nor local backup power to operate their actuators, so they had to drag batteries and portable air compressors into the area to open them.

In short, the operators were right not to trust the sensors. Just imagine the panicked operators in the dark (the control room did not even have its own battery backup) trying to figure out what to do. In short, I do not criticize the operators at all. They did the best they could with what they had (a bunch of manual switches and indicators without interlocks and not even a graphic panel), but I do blame the semi-manual mode of operation, unassisted by automatic safety controls, which they had to work with.

When my book is published this summer, giving the detailed specifics of how automation would have prevented Three Mile Island, Chernobyl and Fukushima, I know that I will receive some defensive letters like Mr. Daigler's, but I also know that the smart operators of the 438 nuclear power plants around the world will go back to their plants and implement the automatic safety systems I came up with to make those plants safer in this age of cyber terrorism.

Béla Lipták
liptakbela@aol.com

More Voices

Automation and Fukushima: Not So Fast
05/01/2013
A Reader Responds to Liptak's Article on Fukushima Saying That We Have No Reason to Suspect That the Instruments Did Not Operate Correctly. Liptak Responds

Reader Feedback: Who's the Boss?
05/01/2013
Google Doesn't Respect Authority. Google Search Results Are Only a Reflection of the Respect Granted by Others

Reader Feedback: Basic PID and Control Issues
04/02/2013
Voices From the ControlGlobal Community...Our Readers Talk About PID

Reader Feedback: Cybersecurity Risk
04/02/2013
When Will the Government Take Cybersecurity Risks Seriously?

Reader Feedback: Long-Distance Calibration
04/01/2013
A Reader Writes In to Tell Us That the Users We Quoated in an Article Are Not Considering the Latest Technology Presented at an ISA International Instrumentation Seminar

Reader Feedback: When Will There Be an App for That?
03/06/2013
A Reader Asks Us When Will We Have an App for iPad

Reader Feedback: Wired vs. Wireless
03/05/2013
A Reader Tell Us About Powerline Communication

Reader Feedback: Process Safety
03/04/2013
Sometimes Even the Best Maintenance Practices Fail to Manage to Keep Some of These Plants Safe

Thoughts on Without Wires
01/30/2013
Wireless Is Used Instead of Doing Nothing at All or Doing It Manually

Reader Feedback: Consider These for The Top 50 Automation Companies
01/01/2013
Readers Asks Us to Consider Balluff, Sick (Optical Sensing Products) for Our Top 50 Automation Companies

Feedback: Wireless Is Easy-Peasy
12/03/2012
A Readers Writes In to Tell Us He Is Perplexed at the Perception of Wireless. Read More to Find Out Why

Feedback: Not All Digital Transmitters Are
12/03/2012
One of Our Readers Takes Issue With the Reference to Manufacturers' "Digital Transmitters" in Rezabeck's Latest Article. See Why

One Page Short of a Story?
10/02/2012
Why Would You Not Mention the Most Popular Meters That Measure Both Area and Velocity?

Securing Control Systems in Cyberspace
10/02/2012
One of Our Readers Says That Even the ISA99 Memeber Will Say It Is Hard to Quantify Security From Their Security Access Level (SAL) Work

Twitter Time Well-Spent
10/02/2012
Using Twitter to Listen and Discover New Things Is Time Well Spent

Wireless a Matter of Choice
08/27/2012
End Users Get to Choose Which Protocol Meets Their Needs the Best

Technology: Keep the Print
08/27/2012
Don't ever Kill the Magazine

Help Wanted
08/03/2012
Reader Tells Us We Were On the Mark Regarding the Current Job Market

The Case Against Lambda Tuning
07/31/2012
Understand the Framework of Using Internal Model-Based Control (IMC) to Come Up With PID Parameters

What's Wrong with VFDs?
07/04/2012
Why Is There Limited Adoption of VFDs in the Process Industry?

Help for Fukushima?
07/04/2012
Our Reader Alex DeVolpi Was Drawn Out of Retirement by the Fukushima Crisis. Find Out Why

More STEM Ideas
06/06/2012
Teacher Encourages Students to STEM Careers by Providing Them With Magazines That Feature STEM Careers

Thanks for the Thought
06/05/2012
Seeing Things in a Different Way. It Takes a Little More Than Just Turning On the Faucet to Get a Drink

STEM: Competent People Reply
06/04/2012
Lets Help Our STEM Students While They're Still Students

Getting the Kids Interested
05/04/2012
Presentation is Key! See How a Retired Professional Inspires Kids to Be Interested in Science and Engineering. The More Flash, Splash and Wow, the Better

What Happened to the E and T in STEM?
04/03/2012
Schools Today Keep Emphasizing the S and the M, but Hardly Concentrate on Teaching Engineering and Technology Areas of Manufacturing, Construction, Communications and Transportation

What's the Best PID Execution Time?
04/03/2012
We Still Should Remember the Nyquist Sampling Theorem

Misplaced ICS-CERT Priorities
04/03/2012
If Not Asked, ICS-CERT Can't Help

Process Manufacturing and Society's Current Values
04/03/2012
Society Has Devoted the Last 40 Years to Passing the Message That Manufacturing Is Dirty, Dangerous and Unrewarding

Taking on Industrial Control Security Issues
04/03/2012
What's It Going to Take Before We Start Getting Real about Industrial Control Security Issues

Is STEM Education Gone for Good?
03/05/2012
Employers Today Abuse the H1-B Visa Program and Want to Pay Next to Nothing for a "Rocket Scientist"

The Future of Manufacturing?
03/05/2012
Here Is A Reader's Point of View on What Manufacturing in America Actually Would Look Like

An Update on Liptak and Shinskey
02/06/2012
Greg Shinskey Continues to Do Consulting and Bela Liptak Talks on Optimization and Safety

Really? A Political Diatribe?
02/06/2012
Reader Disagrees with Editor in Chief Walt Boyes's View on External Cyber Attacks Dangers and U.S. Cybersecurity Policies

Liar, Liar, Pants on Fire?
02/06/2012
Our Very Own Ask the Experts Moderator Bela Liptak Learns a Lesson From One of Our Readers. Liptak Admits That Even Knowledgable People Can Be Wrong

Safety First?
01/05/2012
The Wind Power Industry Is Experiencing a Learning Curve in Safety and Accident Prevention

More About VFDs
01/05/2012
Why Flow Control With a VSD on a Pump Is for the Most Part Linear

Basics of Analyzer Systems Busted!
11/03/2011
You're Right. Here's the Correct Wording

Nice Article
11/03/2011
Reader's Agree With Cybersecurity Article

Answer to Our Question of the Month
11/03/2011
Would You Pay for Outside Help to Address Cybersecurity Issues?

A Cybersecurity Wiki?
09/01/2011
There Should Certainly Be a Wikipedia-Like Site for Security Professionals to Turn To for Proven, Tested Remedies and Suggestions

Summer and Stuxnet
08/02/2011
Talking Plant Cybersecurity in the Light of Stuxnet. With No Certifications for Control System Cybersecurity, Anyone Can Be an Expert. Who Does an End User Believe?

Readers Respond to Cybersecurity and Temperature Measurement Compensation
07/05/2011
Readers Agree With Our Cybersecurity Coverage and Ask Why the Methods of Compensation Were Not Addressed by Our Industry Experts

Automation Apps, Gaming Systems and Thermodynamic Steam Quality
06/07/2011
Readers Ask for Clarification on Some of Our Latest Articles

Reader Feedback: Process Automation, Control Valves vs. VFDs and More
05/02/2011
Readers Agree, Disagree and Respond to Some of Our Latest Articles. See What They Have to Say

Fieldbus Errors; Tweet This, Not That
04/04/2011
Factual Errors Connected With Profibus and Foundation Fieldbus and What the Tweet!!?

Control Readers Speak Up
03/08/2011
International Readers Lets Us Know About Automation Training Opportunities Abroad and One of Our Readers Challenges Our Contributing Editor, Bela Liptak

Where to Go for Training
02/10/2011
Process Automation Engineers Look for Online Training. Do You Know of Any Programs?

Your Skills; Security Requirements for Vendors
01/10/2011
Getting the Message Across. WIB's Security Requirements for Vendors is a Good Start

Hoist by our own petard
02/15/2005
Reader Feedback from the February issue says that when the game leaves town, people are left twiddling their thumbs, and that the passivity of engineers is the true enemy, not the Chinese.