Double Containment

‘This containment system includes a complete, secondary enclosure around the primary containment. This reduces the likelihood of a complete loss of containment if the first containment wall fails. Although such a secondary containment system can be quite effective, it is not normally a stand-alone IPL for LOPA.’

Reference: Adapted from Wiley. Guidelines for Initiating Events and Independent Protection Layers in Layer of Protection Analysis. New York, NY, USA: Wiley, 2015. ProQuest ebrary. Web. 20 October 2015.

‘If a tank, vessel, pipe, transport vessel or equipment is intended to serve as the primary container for a material, it can be designed with a secondary containment system to contain or control a release from the primary containment.  Secondary containment systems include, but are not limited to, tank dikes, curbing around process equipment, drainage collection systems, the outer wall of double-walled tanks, etc.’

Reference: Adapted from Center for Chemical Process Safety, “Guidelines for enabling conditions and conditional modifiers in layer of protection analysis (LOPA)”, Wiley, 2014, New York, NY.