March, 2006

200601MarAll DayPressure relief systems - do you see any hazards here?Process Safety Beacon | ANY open pipe is a potential chemical discharge!Lessons:Operational IntegrityLanguage:EN Origin: CCPS Document Type:Bulletin


1. The discharge from the relief valve in picture #1 is directed toward a personnel access platform above. If the relief valve opens while someone is working on the platform, that person would be exposed to the discharged material and possibly injured.

2. The relief valve discharge in picture #2 is through a long, unsupported pipe. The force generated by the material flow could bend, break or restrict the discharge pipe, any of which could lead to personnel exposure or a failure of the system to operate as intended.

3. The discharge from the relief valves in picture #3 is directed downward, toward an area where people could be working. As in the first picture, anyone working in this area when a relief valve opens could be injured. The discharge pipes are also long and unsupported as in picture #2.

These pictures illustrate hazards found in many plants which handle chemicals. Relief devices often discharge to a ‘convenient’ location – and that may not be the same as a ‘safe’ location

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