Interpretation Response #PI-71-082
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Mr. John Searcy
Tennessee Public Service Comm
Cordell Hull Building
Nashville, Tennessee 37219
Dear Mr. Searcy:
This letter id a further reply to your letter of October 5, 1971, in which you posed the question in paragraph 192.197(c)(2), it is stated that a service regulator and a monitoring regulator are required. Would you consider two (2) regulators in series both set at the same pressure as being a service regulator and a monitoring regulator?
In answer to your question the requirements of 49 CFR 192.197(c)(2) will be met with two regulators in a series, but it will be necessary to have some difference in the setting of the two regulators to avoid operating difficulties. The sketches that you submitted of the various options open for the design of a regulatory installation conforms to the intent of §192.197(c).
Joseph C. Caldwell
Office of Pipeline Safety
|Control of the pressure of gas delivered from high-pressure distribution systems