[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: 30CFR77]

[Page 633]
 
                       TITLE 30--MINERAL RESOURCES
 
  CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
 
PART 77_MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK 
AREAS OF UNDERGROUND COAL MINES--Table of Contents
 
                        Subpart D_Thermal Dryers
 
Sec.  77.304  Explosion release vents.

    Drying chambers, dry-dust collectors, ductwork connecting dryers to 
dust collectors, and ductwork between dust collectors and discharge 
stacks shall be protected with explosion release vents which open 
directly to the outside atmosphere, and all such vents shall be:
    (a) Hinged to prevent dislodgment;
    (b) Designed and constructed to permit checking and testing by 
manual operation; and
    (c) Equal in size to the cross-sectional area of the collector 
vortex finder when used to vent dry dust collectors.