"Class name retrieved from Norsok CAD symbol libraries, Z-CR-004, draft 3, October 1996" . "Recorded" . "SPECTACLE BLIND NORMALLY OPEN" . "SPECTACLE BLIND NORMALLY OPEN" . "RDS311804" . "A blind is normally put in between two flanges and creates a physical barrier for the fluid inside the pipe." . "RDS999417917" . "1997.04.03" . .