A mon avis "blinds' a ici le sens de "physical barrier".

"Isolation" est à comprendre aussi au sens d'empêcher d'entrer en contact physique.
Cf.:
PROCESS DESIGN
www.pdhonline.org/courses/m182/Process Design P-001.pdf
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the definition in this NORSOK standard. ... Isolation means a physical barrier (blind) or a tested barrier .... If the overflow line can be blocked or have ... design point temperature to allow for lower efficiency and higher pressure ratio at compressor ... integrity pressure protections system (commonly named HIPPS) as the ...