In most cases the human brain would suffer irreversible brain damage after 3 minutes without oxygen. Are we prepared to rescue or resuscitate personnel entering enclosed spaces for work within this time frame?
By the time a person is rescued from an enclosed space it is, in most cases, too late to provide any type of resuscitation. Even when an enclosed space entry is properly supervised, the lack of preparedness for rescue makes it impossible to reverse the state of the casualty. Preparedness comes with regular training and practice during the drills and it is for this reason we recommend that time based goals be set during enclosed space entry drills so that the crew understands the associated risks.
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