3.21. Piping adjacent to equipment
3.21.1. Isolation of equipment
In this section, isolation is subdivided into two categories:
1. Positive isolation, in which no leakage can be tolerated (e.g., for safety or contamination reasons)
2. General isolation, in which the requirements are less critical than for (a).
In certain circumstances, it may be necessary for operational reasons or additional security to provide a combination of (a) and (b).
3.21.2. Positive isolation
1. Positive isolation should be accomplished by one of the following:
a. Removal of a flanged spool piece or valve and fitting of blind flanges to the open-ended pipes
b. Line blind
c. A spade in accordance with standards. The arrangements of spading points, together with venting, draining, ...