On February 18, 2020, the audible alarm and light outside the Ammonia plant was activated at approximately 6:40 pm. The plant operator checked the NH3 (ammonia) readings and it read 43 ppm (parts per million). At 6:45 pm the readings increased to 51ppm and staff activated the Emergency Response Plan, contacted 911, the Chief Engineer, and evacuated the building to muster in the lobby of the building. By the time the fire department responded, the readings had dropped to 0 ppm.
Operators upon inspection of the #6 compressor discharge valve bonnet “weep hole” using litmus test paper, (ammonia leak detection test method), observed that the test paper indicated a leak in the discharge valve. The operators tightened the discharge valve. There was no physical damage to the valve other than the valve began to leak.
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Pen points to discharge valve bonnet weep hole. This allows ammonia to leak out and be detected in the event that the valve is leaking. |
INVESTIGATION CONCLUSIONS