Engineering Disasters: Overview of Chernobyl Accident

When I think of nuclear disasters my first thought is Nagasaki and Hiroshima. These tragic events caused during an act of war was a traumatic devastating event in history. Chernobyl another disaster was perhaps the most outrageous display of lack of ethics event in recent modern day history. Chernobyl's instant killing of the 30 workers pales to the estimated 600,000 (Deaths due to the Chernobyl disaster) deaths that can be attributed to this selfish series of events. Chernobyl nuclear power complex began construction in 1970, 130 kilometers north of the city of Kiev, Ukraine which at the time was part of the Soviet Union. Chernobyl was designed as a four nuclear reactor complex in which the first two reactors, units one and two were completed by 1977. Units three and four were completed in 1983.

Chernobyl was designed for military use as a continuous supply not reactor necessarily a fluctuating power source(Chernobyl Disaster). During the construction of Chernobyl there were many sited deviations to the design. For example, "The pillars of generator room were erected with a deviation of up to 100mm from the reference axis and the horizontal connections were absent. Also there was a deviation in the wall panels of up to 150mm" (Ethical Issues Concerning the Chernobyl Nuclear Disaster). Pouring of the foundation was poured with gaps due to the inconsistency of the cement plant. Even the backfilling to the foundation was flawed which caused damage to the waterproofing and therefore allowed ground water to seep into the station and radioactive material to seep out of the station into the environment.

What made Chernobyl such a well-known occurrence happened on April 25, 1986 when personnel were testing how long the turbines of reactor 4 could spin and still maintain supplying power. The test was to be completed so that if the reactors were shut down unexpectedly, a disaster could be Keck2 averted. This same test was completed a year before which showed flaws in the system, so corrective actions were completed and were to be tested on the historic day of April 25, 1986. So what went wrong? The experiment started by disconnecting from the grid to determine how long one generator could power some of the reactors safety systems. This residual power could run cooling pumps in an emergency situation. The experiment started at 1: 05 pm on April 25, 1986, when the reactor output dropped to 1600MW one of the generators was shut off. The experiment was to take place on the second generator after the output went down to 700 to 1000 megawatts. At about 2: 00 pm the operators turned off the emergency cooling system.

The reason this was done was to avoid the emergency cooling system to turn on during the experiment. This was a very serious violation of safety regulations. The next few hours the operators were having a difficult time trying to stabilize the plant so the experiment continued to be delayed. An automatic control was disengaged which caused the power at one point to reach 30 MW. Xeon began to buildup, which is a byproduct of decay, which slowed down the chain reaction of nuclear power which in effect caused the output to drop. The operators corrected this problem by removing many control rods. After removal of the control rods power reached 200MW by 1: 00 am on April 26 and it was decided at that time to continue with the experiment. To continue with the experiment, two additional pumps were started up as per the test plan. The reactor were still running at much lower output than was planned, these 2 pumps caused too much cooling which in turn caused too much steam (Chernobyl Accident). Automatic shut down signal were blocked by the operators which disabled part of the emergency shutdown procedure. The overpressure caused a massive explosion which released fission products into the air. A second explosion caused pieces of the fuel chambers to explode. The fuel started a number of fires in which was the main release of radioactivity into the environment. So in essence, ironically a failed safety experiment in which several safety violations occurred concluded in a disaster.

Was this disaster avoidable? The answer is astoundingly yes! Lack of trained operators appear to be a large contributor to what went wrong. When operators began to circumvent safety features such as emergency shutdown procedures this was a huge mistake in which it appears could have averted the entire problem. Were the operators properly trained on what could wrong when these features were shutdown? Safety procedures are in place for a reason, a life lesson of what could go wrong and the catastrophic results when safety protocols are not followed. The Chief Engineer in charge of the control room on April 25, 1986, Anatoly Steponvich Dyatlov, "Anxious to complete a scientific experiment that had been ordered by Moscow, he bullied his subordinates into taking unnecessary risks"( Michael Dobbs). Can you imagine, the Chief Engineer, bullies the operators to commit serious safety violations! Did Anatoly Dyatlov understand the consequences of what could happen? Was he capable of being in charge? At end of the catastrophic event, Mr. Dyatlov was sentenced to 10 years in a labour camp (Michael Dobbs). A pretty small price to pay for the thousands of deaths which occurred needlessly. Process controls was another area in which I believe the disaster could have been averted.

For example, why were operators allowed to bypass safety features? Should this not have been designed so that operators could not override? I would think that if these features were so critical, there simply should be no way of circumventing them. During the construction of Chernobyl as mentioned previously, shortcuts were taken causing serious flaws, but what about actual design short comings. For example, nuclear reactors in Canada are built with cement encasement in which literally a 747 plane could crash into the reactor without any radiation escaping. Chernobyl was not designed with these multiple layers of physical barriers. Another design flaw was the insertion of the control rods would not go into the mating holes to control the output due to the lack of hydraulic force needed to overcome the swelling of the holes due to the heat. Another design flaw Chernobyl had was a "positive void coefficient" which basically means that a nuclear chain Keck4 reaction increased when water coolant was lost, which caused an uncontrollable influx of power. In Canada reactors have "negative void coefficient" which will automatically shutdown the chain reaction when coolant is lost (What could have been done to prevent Chernobyl?). This feature would have almost certainly averted the catastrophe.

Public safety was a secondary concern for the Soviet Union after the explosions occurred and the deadly radiation was spewed into the atmosphere. The Soviet's first priority was to try to hide what happened. The Soviet Union kept not only their citizens in the dark but the entire world until the evening of April 28, 1986. Valuable minutes went by without evacuation. A complete unforgivable selfish acts by the Soviet Union and complete disregard to public safety. Another astounding fact is the Soviet Union kept 3 reactors in operation long after the explosion; reactors 1 until 1996, unit 2 until 1991 and unit 3 going until the year 2000. Can you imagine people working in this radioactive cesspool ( Chernobyl 1-3 enter decommissioning phase)! Wow, it is hard to believe a country can be so ruthless with complete disregard to human life! Professional engineering Code of Ethics" have a clearly defined duty to society, which is to regard the duty to public welfare as paramount, above their duties to clients or employers" (Code of Ethics) Did Anatoly Steponvich Dyatlov perform in an ethical manner? The epitome of absolutely not. Mr Dyatlov complete disregard for public safety and his duty to the operators was reckless and certainly unethical by the mere definition listed above.

How about the Soviet Union's disregard for human life and only trying to cover up the disaster? Can you believe how utterly ruthless the Soviet Union was in not evacuating their citizens and not immediately letting everyone know what happened, not only unethical but truly disgusting. The PEO code of ethics goes on to state " fairness and loyalty to the practitioner's associates, employers, clients, subordinates and employees" (Code of Ethics). Let's reflect on this for a moment, was Mr Dyatlov fair to his subordinates? Obviously not. Keck5 "Devotion to high ideals of personal honour and professional integrity" (Code of Ethics), how did Mr Dyatolov perform here? Sadly, the Soviet Union performed even worse! "Knowledge of developments in the area of professional engineering relevant to any services that are undertaken" (Code of Ethics). Was Mr. Dyatlov knowledgeable enough to complete the testing? Were the people who ordered the test, were they knowledgeable enough to ask the task to be completed? Obviously not! "Competence in the performance of any professional engineering services that are undertaken" (Code of Ethics). Was Mr. Dyatolov competent? Was the Soviet Union competent in ordering the test? Obviously not! History is very valuable to engineers and society. History are lessons, lessons need to be studied so that the same mistakes are not repeated. So many valuable lessons learnt from this incident. Taking on tasks that perhaps you are not completely capable of taking on, it is okay to say no or simply that I do not feel comfortable taking this task on due to my lack of knowledge. To bully subordinates is by definition the opposite of teamwork.

When working within a team the results are always better, this has been proven time and time again. What about the complete disregard for life after the explosion by the Soviet Union, how can there be such a disregard for life? The flawed design of Chernobyl, how can an engineer design such a facility with no regard to ethics. I can hardly imagine bypassing safety features, was the training for these individuals adequate? Where were the safety fool proofs, which should not have been able to be circumvented? The short cuts in the construction, one cannot simply deviate from the design without understanding the consequences. As I reflect on the pictures of innocent children who suffered the consequences of these selfish unethical acts and the net effect of these acts. Let history make us remember what unethical decisions could cause!