---
kind: "section"
citation: "46 C.F.R. § 154.407"
title: "46"
number: "154.407"
heading: "Cargo tank internal pressure head."
url: "https://uscodex.org/cfr/46/154.407"
---

# §154.407. Cargo tank internal pressure head.

- (a) For the calculation required under § [154.406(a)(1)](/cfr/46/154.406.md?p=a-1) and [(b)](/cfr/46/154.406.md?p=a-b), the internal pressure head (heq), must be determined from the following formula:
- (b) The (hgd) max is determined for the β direction, on the ellipse in Figure 1, which gives the maximum value for hgd.
- (c) When the longitudinal acceleration is considered in addition to the vertical transverse acceleration, an ellipsoid must be used in the calculations instead of the ellipse contained in Figure 1.

## Notes

### Authority

Authority: 46 U.S.C. 3703, 9101; Department of Homeland Security Delegation No. 0170.1.

### Source

Source: CGD 74-289, 44 FR 26009, May 3, 1979, unless otherwise noted.