What’s the difference between Firm service and Interruptible service?
Firm service is the highest quality sales or transmission service offered to customers under
a filed rate schedule that anticipates no planned interruption. It is usually associated
with distribution companies that serve residential customers and other "high priority
end-users," but can also apply to upstream pipelines and other Interruptible service is
subject to interruption at the option of the pipeline. Tariffs for interruptible service are
cheaper than firm service.