# Indiana Public Service Commission — Pipeline Safety Interpretation

**Citation:** PI-71-075  
**Type / status:** guidance / guidance  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** Not stated  
**Published:** 1971-08-18

PI-71-075 response to Indiana Public Service Commission concerning 192.167.

## Document text

<<<PAGE 1>>>

Mr. D. J. Hendrickson
Indiana Public Service Commission
901 State Office Building
Indianapolis, Indiana 46204
Dear Mr. Hendrickson:
Thank you for your letter of August 3, 1971, requesting an interpretation of §192.167 of 49 Code
of Federal Regulations, Compressor station: emergency shut down.
In effect you ask two questions. The first is if a station is attended only during start up and shut
down and is totally unattended while in operation does it qualify as being unattended. The answer
is yes. If personnel are not assigned to the station during the period of operation the station is
unattended.
The second question you pose is whether the regulation applies to all compressor stations. Again
the answer is yes. The only compressor stations that are excepted are those that are unattended
field compressors of 1,000 horsepower or less. The use of the word field as a modifier is a carry
over from §843.431 of the B31.8 1968 code. It denotes a compressor station that is used to
pump gas directly from a gathering system of a production field.
We hope that this interpretation will clarify the problems that you are having in understanding
§192.167.
Sincerely,
Joseph C. Caldwell
Acting Director
Office of Pipeline Safety
DB
C:\WP51\INTERPRT\192\167\71-08-18
1

<<<PAGE 2>>>

Mr. Joseph C. Caldwell
Office of Pipeline Safety
Department of Transportation
Washington, D. C. 20590
Dear Mr. Caldwell:
Re: CFR Part 192, Section 192.167; Compressor Stations; Emergency Shutdown
Will you please give us an interpretation of the words "unattached" and "field"?
If a station is attended only during start-up and shut-down and is totally unattended while in
operation does it qualify as being "unattended", or does it have to be completely remotely
operated to be "unattended?"
It would be reasonable to assume that this requirement applies to all compressor stations---
transmission, distribution and storage field---so just what compressor stations are exempt as being
"field" compressors?
Very truly yours,
D. J. Hendrickson
Director
Pipeline Safety Division
DB
C:\WP51\INTERPRT\192\167\71-08-18
2

## Provenance

- Official: Yes
- Source: <https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/Pipeline/1971/PI71075.pdf>
- Source ID: `phmsa`
- SHA-256: `94ca7dada382acb164d90f7a1396a3df062b63e2c771af33466d6eb05e09ec6e`
- Retrieved: 2026-08-20T00:59:31.977Z
- Exported: 2026-08-22T22:28:59.001Z
- Document slug: `phmsa-interpretation-pi-71-075`

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