---
kind: "section"
citation: "40 C.F.R. § 63.164"
title: "40"
number: "63.164"
heading: "Standards: Compressors."
url: "https://uscodex.org/cfr/40/63.164"
---

# §63.164. Standards: Compressors.

- (a) Each compressor shall be equipped with a seal system that includes a barrier fluid system and that prevents leakage of process fluid to the atmosphere, except as provided in [§ 63.162(b)](/cfr/40/63.162.md?p=b) of this subpart and paragraphs [(h)](#h) and [(i)](#i) of this section.
- (b) Each compressor seal system as required in [paragraph (a)](#a) of this section shall be:
  - (1) Operated with the barrier fluid at a pressure that is greater than the compressor stuffing box pressure; or
  - (2) Equipped with a barrier fluid system degassing reservoir that is routed to a process or fuel gas system or connected by a closed-vent system to a control device that complies with the requirements of [§ 63.172](/cfr/40/63.172.md) of this subpart; or
  - (3) **Equipped with a closed-loop system that purges the barrier fluid directly into a process stream.**
- (c) The barrier fluid shall not be in light liquid service.
- (d) Each barrier fluid system as described in [paragraphs (a) through (c)](#a..c) of this section shall be equipped with a sensor that will detect failure of the seal system, barrier fluid system, or both.
- (e)
  - (1) Each sensor as required in [paragraph (d)](#d) of this section shall be observed daily or shall be equipped with an alarm unless the compressor is located within the boundary of an unmanned plant site.
  - (2) The owner or operator shall determine, based on design considerations and operating experience, a criterion that indicates failure of the seal system, the barrier fluid system, or both.
- (f) If the sensor indicates failure of the seal system, the barrier fluid system, or both based on the criterion determined under [paragraph (e)(2)](#e-2) of this section, a leak is detected.
- (g)
  - (1) When a leak is detected, it shall be repaired as soon as practicable, but not later than 15 calendar days after it is detected, except as provided in [§ 63.171](/cfr/40/63.171.md) of this subpart.
  - (2) A first attempt at repair shall be made no later than 5 calendar days after each leak is detected.
- (h) A compressor is exempt from the requirements of [paragraphs (a) through (g)](#a..g) of this section if it is equipped with a system to capture and transport leakage from the compressor drive shaft seal to a process or a fuel gas system or to a closed vent system that captures and transports leakage from the compressor to a control device meeting the requirements of [§ 63.172](/cfr/40/63.172.md) of this subpart.
- (i) Any compressor that is designated, as described in [§ 63.181(b)(2)(ii)](/cfr/40/63.181.md?p=b-2-ii) of this subpart, to operate with an instrument reading of less than 500 parts per million above background, is exempt from the requirements of [paragraphs (a) through (h)](#a..h) of this section if the compressor:
  - (1) Is demonstrated to be operating with an instrument reading of less than 500 parts per million above background, as measured by the method specified in [§ 63.180(c)](/cfr/40/63.180.md?p=c) of this subpart; and
  - (2) Is tested for compliance with [paragraph (i)(1)](#i-1) of this section initially upon designation, annually, and at other times requested by the Administrator.

## Notes

### Amendments

[59 FR 19568, Apr. 22, 1994, as amended at 59 FR 48176, Sept. 20, 1994; 62 FR 2790, Jan. 17, 1997; 64 FR 20198, Apr. 26, 1999; 89 FR 43221, May 16, 2024]

### Source

Source: 59 FR 19568, Apr. 22, 1994, unless otherwise noted.

### Authority

Authority: 42 U.S.C. 7401 et seq.

### Source

Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted.

### Amendments

[59 FR 19568, Apr. 22, 1994, as amended at 59 FR 48176, Sept. 20, 1994; 62 FR 2790, Jan. 17, 1997; 64 FR 20198, Apr. 26, 1999; 89 FR 43221, May 16, 2024]