Well, it’s not often that I disagree with the OSHA technical team that writes LOIs, but this one is a MAJOR MISTAKE. I have debated this topic for 30 years and now my argument just got squashed by the agency. In their 2025 LOI, OSHA stated:
If the employer's evaluation of the space determines that the piping does not terminate in the space and that no potential exists for rupture or leakage of materials into the space, then isolation of the piping is not required.
NFPA 350 makes a similar comment:
