Report of Investigations 8785: Kettlebottoms: Their Relation to Mine Roof and Support

Details

• Journal Article:
  NTIS: PB84/10079
• Personal Author:
  Chase, Frank E. ; Sames, Gary P.
• Description:
  Kettlebottoms are columnar masses of rock--the preserved casts of ancient tree stumps--embedded in coal mine roof strata (of which they are a part). Because unsupported kettlebottoms can detach from a mine roof without warning, they are a hazard to miners. The primary objectives of this investigation were (1) to better define and describe kettlebottoms and (2) to evaluate kettlebottom support techniques in terms of safety and effectiveness. A telephone survey of mine operators, interviews with Mine Safety and Health Administration (MSHA) personnel, and underground mine visits were conducted in Pennsylvania, West Virginia, and Kentucky. Information gathered during this investigation indicates that the size and frequency of kettlebottoms in mine roof are dependent upon past geologic events and biological processes active during the deposition of roof sediments. To ensure the safety of mine personnel, all undermined kettlebottoms should be supported. The roof should be bolted next to kettlebottoms less than 3 ft in diameter, close enough to allow a portion of a wood or steel header to be extended beneath each kettlebottom for support. Two bolts and a wood plank or steel strap should be employed to support kettlebottoms over 3 ft in diameter. [Description provided by NIOSH]
• Subjects:
  Mining Occupational Health Safety
• Source:
  NTIS: PB84/100791; :1-12
• Series:
  NIOSH Numbered Publications   ; Mining Publications  
• Subseries:
  Report of Investigations
• Document Type:
  Text
• Genre:
  Report
• Place as Subject:
  Kentucky ; OSHA Region 3 ; OSHA Region 4 ; Pennsylvania ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PRC - Pittsburgh Research Center
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  16 pdf pages
• NIOSHTIC Number:
  nn:10003005
• Federal Fiscal Year:
  1983
• Peer Reviewed:
  False
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:df16e24ff9ae12abdf5f18e63e475fecdc7846f72a7b1fe15bfd0c98a7f1e3e1be282b472b536b05062b449ac6d19932844369a95c213155ca4861cb0fd9b5eb
• Download URL:
  https://stacks.cdc.gov/view/cdc/10553/cdc_10553_DS1.pdf
• File Type:
  [PDF - 5.79 MB ]