---
kind: "section"
citation: "33 C.F.R. § 154.2108"
title: "33"
number: "154.2108"
heading: "Vapor-moving devices."
url: "https://uscodex.org/cfr/33/154.2108"
---

# §154.2108. Vapor-moving devices.

- (a) Paragraphs [(b)](#b) and [(e)](#e) of this section apply only to facilities collecting vapors of flammable, combustible, or non-high flash point liquid cargoes.
- (b) Each inlet and outlet to a vapor-moving device that handles vapor that has not been inerted, enriched, or diluted in accordance with [33 CFR 154.2107](/cfr/33/154.2107.md) must be fitted with a detonation arrester; however, the outlet detonation arrester may be omitted if the vapor-moving device is within 50 times the pipe's diameter of the detonation arrester required by [33 CFR 154.2109(a)](/cfr/33/154.2109.md?p=a).
- (c) If the vapor is handled by a reciprocating or screw-type compressor in the vapor collection system, the compressor must be installed with indicators and audible and visible alarms to warn against the following conditions:
  - (1) Excessive gas temperature at the compressor outlet;
  - (2) Excessive cooling water temperature;
  - (3) Excessive vibration;
  - (4) Low lube oil level;
  - (5) Low lube oil pressure; and
  - (6) **Excessive shaft bearing temperature.**
- (d) If the vapor is handled by a liquid ring-type compressor in the vapor collection system, it must be installed with indicators and audible and visible alarms to warn against the following conditions:
  - (1) Low level of liquid sealing medium;
  - (2) Lack of flow of the liquid sealing medium;
  - (3) Excessive temperature of the liquid sealing medium;
  - (4) Low lube oil level;
  - (5) Low lube oil pressure, if pressurized lubricating system; and
  - (6) **Excessive shaft bearing temperature.**
- (e) If the vapor is handled by a centrifugal compressor, fan, or lobe blower in the vapor collection system, construction of the blades or housing must be one of the following:
  - (1) Blades or housing of nonmetallic construction;
  - (2) Blades and housing of nonferrous material;
  - (3) Blades and housing of corrosion resistant steel;
  - (4) Ferrous blades and housing with one-half inch or more design tip clearance;
  - (5) Nonferrous blades and ferrous housing with one-half inch or more design tip clearance; or
  - (6) Blades of aluminum or magnesium alloy and a ferrous housing with a nonferrous insert sleeve at the periphery of the impeller.

## Notes

### Source

Source: USCG-1999-5150, 78 FR 42618, July 16, 2013, unless otherwise noted.

### Authority

Authority: 33 U.S.C. 1321(j)(1)(C), (j)(5), (j)(6), and (m)(2); 46 U.S.C. 70011, 70034; sec. 2, E.O. 12777, 56 FR 54757; Department of Homeland Security Delegation No. 00170.1, Revision No. 01.2. Subpart F is also issued under 33 U.S.C. 2735. Vapor control recovery provisions of Subpart P are also issued under 42 U.S.C. 7511b(f)(2).