Witness to a catastrophic near miss!

On 29.11.1984, I was working  in an ammonia plant when a cylcone hit the place. Management had taken advance action and instructed us to shut off the back end of ammonia plant (the back end of the ammonia plant involves high pressures). We had shut down the back end and were waiting for the cyclone to hit us. The wind speeds were very high and all of us were taking shelter in the control room. A complaint then came in from the  another plant that was located within the same complex, that they were experiencing severe ammonia odour.  Thinking that the pilot burners of the ammonia derrick supported flare that was provided for emergency venting of the ammonia storage tank was put off by the high winds, I requested operators to go out and check them. Three operators had to go, holding each other tightly,as the wind speed was so high and could blow a man off his feet. After a short while they came back and reported that the flare was missing. I went out to check with another team and we found to our horror that the flare structure had collapsed on the main ammonia vapor line coming from the tank. The derrick structure was weak and could not bear the brunt of the wind speeds, but the main flare gas pipe was in good condition and when the derrick toppled, the main gas pipe prevented it from falling all of a sudden. Instead it fell slowly and came to rest on the ammonia vapor line! The 8" main ammonia vapour line from the tank was dented, but did not leak.
When you conduct your asset integrity program, pay attention to structures. Nowadays, in many plants, painting schedules are taking a back seat, with the net result that corrosion creeps in. Corrosion is a silent killer. It will hit you one day if you don't maintain your assets.
Interestingly, recently I read an article where a complete flare structure repair was done with minimum downtime in a plant.Read the article in this link.