---
kind: "section"
citation: "30 C.F.R. § 18.98"
title: "30"
number: "18.98"
heading: "Enclosures, joints, and fastenings; pressure testing."
url: "https://uscodex.org/cfr/30/18.98"
---

# §18.98. Enclosures, joints, and fastenings; pressure testing.

- (a) Cast or welded enclosures shall be designed to withstand a minimum internal pressure of 150 pounds per square inch (gage). Castings shall be free from blowholes.
- (b) Pneumatic field testing of explosion-proof enclosures shall be conducted by determining:
  - (1) Leak performance with a peak dynamic or static pressure of 150 pounds per square inch (gage); or
  - (2) A pressure rise and rate of decay consistent with unyielding components during a pressure-time history as derived from a series of oscillograms.
- (c) Welded joints forming an enclosure shall have continuous gastight welds.

## Notes

### Source

Source: 36 FR 7007, Apr. 13, 1971, unless otherwise noted.

### Authority

Authority: 30 U.S.C. 957, 961.

### Source

Source: 33 FR 4660, Mar. 19, 1968, unless otherwise noted.