Human error-power supply failure to air traffic controller radar screen at IGI, New Delhi

In an incident involving human error, an electrician at Indira Gandhi International (IGI) airport, New Delhi switched off a miniature circuit breaker (MCB) while fixing an electrical fitting. This MCB as it is reported, is on the line supplying power to air traffic controller (ATC)  radar screens and screens went blank. The standby power (may be diesel generator) came into line in a few seconds and rebooting of all consoles and restoration took about 45 minutes.

Meanwhile, the air traffic controllers having tough time,  guided the planes for safe landing with their experience. All departures were put on hold in between. As it is during such emergency times, Murphy's law showed its application once again. But the experienced personnel guided even a plane or two, low on fuel to land safely without panic.

From various reports in the internet about the incident, there seems to be failure of, or no uninterrupted power supply (UPS) / inverter backup directly connected to ATC radar system, as the screens went blank. That it took sometime for standby power to come into line, indicates that this is a diesel generator (DG) set power supply. This takes about 30 seconds as we experience in apartment complexes or cinema halls. Generally, people use UPS even for domestic computers, because of fear of losing data. Also, because of power cuts,  people use inverter widely at home and business houses. For critical systems, normal power supply should be through inverter/UPS so that any failure of power supply on upstream side will not affect the operations. Now-a-days, solar powered inverters are also available in the market. This should be in addition to the other backups for use. MCB/any other switch should be located on upstream side of these UPS/inverter, rather than on the downstream end so that mistakes like these will not happen. May be the authorities were confident of their backup systems.

Generally, risk assessment is same for aviation and nuclear industries. The risk assessment should be reviewed and measures should be taken to reduce risk levels. It is horrible to think of so many planes in the air without guidance for landing. 

To avoid such mistakes as in this case, there is a need for safety work permit system as practiced in all industrial facilities, for carrying out any job having impact on human lives, property and or environment. Also, that this important MCB could be switched off by mistake indicates that critical safety systems are not protected or its importance is not recognized. Authorities have to review entire safety practices, identify critical systems having impact on persons/property/environment and prepare documented procedure for implementation. Suitable caution boards/warning signs/names and contact numbers of authorities to be contacted in case of need should be displayed near these critical items. A nodal authority (safety officer) should be identified for entire ATC under  whom, permission/approval should be given for various works so that there will not be any lapse. If more than an authority is identified, there may be a situation that one will not know about permission/approval given by the other. Also, lockout/tagout (LOTO) system, if feasible needs to be put in place. 

Apart from power failure like above, it is possible that due to hardware or software glitch or even entry of insects/lizards, the screens can go blank or computer system can hang and for such a situation also, one has to plan for diverse redundant systems to avoid surprise/panic. Whenever, there is no communication between computers or computer and signal receiving/emitting towers or no change in data for a specified time (may be a second or milli second or some other duration depending upon the criticality), audio-visual alarms should be incorporated to alert the concerned personnel for immediate action.

http://www.dnaindia.com/india/report_radar-screens-at-igi-airport-atc-go-blank-outgoing-flights-hit_1797953

http://www.indianexpress.com/news/igia-radar-screens-go-blank-flights-disrupted/1071724/

http://timesofindia.indiatimes.com/india/Power-put-off-by-mistake-IGI-Airport-radars-go-dead/articleshow/18410667.cms?

http://www.indianexpress.com/news/radar-screens-go-blank-again-at-igi-airport/572005/2

Fire breaks out at textile firm | Deccan Chronicle

Fire breaks out at textile firm | Deccan Chronicle. The fuel oil leak from pipes connected to boiler catches fire. Four workers in the first floor were charred to death as they could not escape from stairs that was filled with sacks and drums which were on fire. Fire tenders reached the spot without water. Police had difficulty to handle the situation in darkness without torch lights. This is a clear example of Murphy's law. Everything went wrong. The fire was extinguished after water was supplied by a private operator. Two officials were booked for negligence and causing injury.

http://www.indianexpress.com/news/now-fire-kills-four-in-midc/850436/
http://www.dnaindia.com/mumbai/report_dombivli-factory-fire-kills-4_1590414
http://www.daybreakingnews.com/post/Four-killed-in-Mumbai-textile-mill-fire-accident-which-occurred-early-in-the-morning-today.aspx
http://ibnlive.in.com/generalnewsfeed/news/four-killed-in-maha-textile-mill-blaze/832307.html
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Who is responsible for safety?

After the last week verdict on Bhopal tragedy for fixing the responsibility, so many people in responsible positions commented about the verdict. The Factories Act 1948 amended after this 1984 accident fixes the responsibility for ensuring safety at the work place on the occupier as well as the manager. It also says (Sec 101) that if the occupier is able to prove that he has given full responsiblity and resources to others down below and that the accident occurred because of deeds of his subordinates without his knowledge, then the said person can be held responsible.

Someone commented that a car owner can't be held responsible, if his driver makes an accident. It is forgotten that the driver was put into job by the owner of the car and nobody else (unless car was stolen and is not reported in the police station).

If managements employ less qualified or unsuitable persons for the job, then there is every possibility that accidents / incidents can take place. In risk assessment, human error is also a factor. In fact, experts say that systems should be designed and put in place such that even a fool can not meddle and lead to accidents.

In the case of Bhopal accident, it is mentioned that the some of the workers, superviors and managers were brought from Battery Division and do not have proper training / exposure to run the plant. Even the audit report of Union Carbide warned about imminent dangers, a few years before the accident. Few accidents occurred earlier also support that a major accident will not occur all of a sudden, but will be preceded by few near misses and minor accidents.

As the plant was not in operation for few months before the accident, poorly trained managers and supervisors decided to switch off the refrigeration system thinking that when plant is not running, nothing will happen (because of lack of knowledge on hazards). Persons were not informed about the hazards, neither they had interest to learn on their own, about what can happen in their day-to-day activities. All of us will be careful to caution our children about their safety when they go to school or college. But we do not follow the same at our work place.

Apart from deactivating refrigeration system, the srubbing unit and flare tower were not kept in working condition. To prove Murphy law, every safety system went wrong simulataneously (neither functional nor available at the time of accident). The water sprinkler, a last resort, had limitations of spraying water upto a height of only 15 m where as the gas eascaped from the flare tower at a height more than this.

There are provisions and punishments for causing deaths due to negligence, callous attitude and accused should be awarded compunded punishments. If the wrong doers are not punished severely, this will send a wrong message to all greedy corporates that nothing will happen to them and they can find some scapegoats at lower levels for the minor punishments.  In the famous novel God Father by Mario Puzo, it is mentioned that underworld people keep some persons with opposing gangs as a surity for the persons from these gangs attending meetings so that they can participate the meetings and leave the place safely. Scapegoats will be found like in the underworld system.

The entire property of the owners of the factory causing such large scale deaths should be confiscated and it is better for governments to work toward making international laws to confiscate properties of the owners in other countries also.






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