Determine when a medical gas line breach/repair triggers recertification/re-verification

Steps

1. Confirm NFPA 99 treats a 'breach' as any pipeline intrusion by physical separation, or any removal, replacement, or addition of a system component
2. Confirm that testing is required after any breach, but the scope/extent of required testing depends on the nature of the work performed — a like-for-like component replacement (e.g., swapping a pressure regulator) may require lesser testing, while work involving brazing or potential internal contamination requires fuller recertification/verification
3. Confirm the exact threshold distinguishing 'partial retest' from 'full recertification' against the current NFPA 99 edition text and/or AHJ interpretation, since this is a judgment call not always spelled out with bright-line criteria in secondary sources
4. Confirm a permit-to-work process is used to require and document testing on the affected downstream portion of the system after any repair or cut-in, closing the loop before the line returns to service
5. Confirm verification after a breach must still be performed by a party independent of the contractor who performed the repair, consistent with the general verifier-independence requirement