---
kind: "section"
citation: "46 C.F.R. § 162.050-20"
title: "46"
number: "162.050-20"
heading: "Separator and bilge alarm test fluids."
url: "https://uscodex.org/cfr/46/162.050-20"
---

# §162.050-20. Separator and bilge alarm test fluids.

- (a) Tests required in §§ [162.050-23](/cfr/46/162.050-23.md) and [162.050-35](/cfr/46/162.050-35.md) must be performed using the following three types of test fluids:
  - (1) Test Fluid A, which is a marine residual fuel oil in accordance with ISO 8217 (incorporated by reference, see [§ 162.050-4](/cfr/46/162.050-4.md)), type RMG 380 (density at 15 °C not less than 980 kg/m 3);
  - (2) Test Fluid B which is a marine distillate fuel oil in accordance with ISO 8217, type DMA (density at 15 °C not less than 830 kg/m 3);
  - (3) Test Fluid C must be a mixture of an oil-in-fresh water emulsion, where 1 kg of the mixture consists of:
    - (i) 947.8 g of fresh water;
    - (ii) 25.0 g of Test Fluid A;
    - (iii) 25.0 g of Test Fluid B;
    - (iv) 0.5 g of surfactant (sodium salt of dodecylbenzene sulfonic acid) in the dry form; and
    - (v) 1.7 g of iron oxides, a black ferrosoferric oxide (Fe3O4) with a particle size distribution of which 90 percent is less than 10 microns, the remainder having a maximum particle size of 100 microns.
- (b) Test Fluid C must be prepared as needed for [§ 162.050-23](/cfr/46/162.050-23.md) or [§ 162.050-35](/cfr/46/162.050-35.md) by using the following procedures:
  - (1) Measure out 1.2 times the quantity of surfactant required from the WORKSHEET FOR DETERMINING CONSTITUENTS OF TEST FLUID C, see figure 162.050-20;
  - (2) Mix it with fresh water and stir well in a small container to make a mixture until the surfactant has been thoroughly dissolved, but use no more than the minimum amount of water necessary to make a complete solution;
  - (3) Fill clean test fluid tank with fresh water with a quantity 1.2 times the volume of the total quantity of water in Test Fluid C needed for the test described in §§ [162.050-23](/cfr/46/162.050-23.md) and [162.050-35](/cfr/46/162.050-35.md);
  - (4) Operate the centrifugal pump B running at a speed of not less than 3,000 rpm with a flow rate at which the volume of the test fluid has been changed out at least once per minute;
  - (5) Add the surfactant mixture from [paragraph (b)(2)](#b-2) of this section first, followed by oil and suspended solids (iron oxides) respectively, both 1.2 times of the required amounts, to the fresh water in the tank;
  - (6) To establish a stable emulsion keep running the centrifugal pump B for one hour and confirm no oil floats on the surface of the test fluid; and
  - (7) After the one hour stated in [paragraph (b)(6)](#b-6) of this section, keep running the centrifugal pump B at reduced speed to approximately 10 percent of original flow rate, until the end of the test.

## Notes

### Amendments

[USCG-2004-18939, 74 FR 3385, Jan. 16, 2009]

### Source

Source: CGD 76-088a, 44 FR 53359, Sept. 13, 1979, unless otherwise noted.

### Authority

Authority: 33 U.S.C. 1321(j), 1903; 46 U.S.C. 3306, 3703, 4104, 4302; E.O. 12234, 45 FR 58801, 3 CFR, 1980 Comp., p. 277; E.O. 12777, 56 FR 54757, 3 CFR, 1991 Comp., p. 351; DHS Delegation 00170.1, Revision No. 01.4.

### Amendments

[USCG-2004-18939, 74 FR 3385, Jan. 16, 2009]