---
kind: "section"
citation: "46 C.F.R. § 56.50-20"
title: "46"
number: "56.50-20"
heading: "Pressure relief piping."
url: "https://uscodex.org/cfr/46/56.50-20"
---

# §56.50-20. Pressure relief piping.

- (a) **General.** There must be no intervening stop valves between the pressure vessel or piping system being protected and its protective device or devices, except as authorized by the Marine Safety Center.
- (b) **Discharge lines.** (Reproduces 122.6.2(d).) Discharge lines from pressure-relieving safety devices must be designed to facilitate drainage.
- (c) **Stop valves.** Stop valves between the safety or relief valve and the point of discharge are not permitted, except as specifically approved by the Marine Safety Center.
- (d) **Reference.** See also § [56.07-10(a)](/cfr/46/56.07-10.md?p=a) and [(b)](/cfr/46/56.07-10.md?p=b) for specific requirements.

## Notes

### Amendments

[CGFR 68-82, 33 FR 18843, Dec. 18, 1968, as amended by CGFR 69-127, 35 FR 9979, June 17, 1970; CGD 77-140, 54 FR 40607, Oct. 2, 1989]

### Source

Source: CGFR 68-82, 33 FR 18843, Dec. 18, 1968, as amended by USCG-2020-0634, 89 FR 50131, June 12, 2024, unless otherwise noted.

### Authority

Authority: 33 U.S.C. 1321(j), 1509; 43 U.S.C. 1333; 46 U.S.C. 3306, 3703; 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 No. 00170.1, Revision No. 01.4.

### Source

Source: CGFR 68-82, 33 FR 18843, Dec. 18, 1968, unless otherwise noted.

### Amendments

[CGFR 68-82, 33 FR 18843, Dec. 18, 1968, as amended by CGFR 69-127, 35 FR 9979, June 17, 1970; CGD 77-140, 54 FR 40607, Oct. 2, 1989]