Exemptions for Pipe

The exemptions and allowances for pipe can, with careful planning save a lot of time and money. They may also mean the difference between making a profit on a project and breaking even, or worse, losing money.

12-in. rule: seismic restraints are not required for pipe if it is mounted with a non-moment generating swivel type connection and all of the hangers in the run are 12-in. or less in length from the supporting structure; and no damage can occur from the expected swing of the pipe. (Restraints are required on equipment that is hung 12-in. or less from the ceiling because equipment behaves more erratically than piping or duct during a seismic event.)

Seismic restraints are not required:

In seismic design category D, E or F with a component importance factor of 1.5, for pipes of a nominal size of 1-in. or less.

In seismic design category D, E or F with a component importance factor of 1.0, for pipes of a nominal size of 3-in. or less.

In seismic design category C with a component importance factor of 1.5, for pipes of a nominal size of 2-in. or less.