[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: 30CFR18.33]



[Page 104]

 

                       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 B_Construction and Design Requirements

 

Sec.  18.33  Finish of surface joints.



    Flat surfaces between bolt holes that form any part of a flame-

arresting path shall be plane to within a maximum deviation of one-half 

the maximum clearance specified in Sec.  18.31(a)(6). All metal surfaces 

forming a flame-arresting path shall be finished during the 

manufacturing process to not more than 250 microinches. A thin film of 

nonhardening preparation to inhibit rusting may be applied to these 

finished metal surfaces as long as the final surface can be readily 

wiped free of any foreign materials.



[57 FR 61210, Dec. 23, 1992]