[Code of Federal Regulations]

[Title 30, Volume 1]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 30CFR18.98]



[Page 129]

 

                       TITLE 30--MINERAL RESOURCES

 

  CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR

 

PART 18_ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES--Table of 

Contents

 

   Subpart E_Field Approval of Electrically Operated Mining Equipment

 

Sec.  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.