Report of Investigations 8888: Overlap Probability for Short-Period-Delay Detonators Used in Undergroud Coal Mining

Details

• Journal Article:
  Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 8888
• Personal Author:
  Bajpayee, T. S. ; Mainiero, Richard J. ; Hay, J. Edmund
• Description:
  The Bureau of Mines investigated coal-mine-type short-delay electric detonators marketed by three domestic manufacturers to determine the accuracy of delays and the probability of overlap between adjacent delay periods. The Winzer index was computed and compared with the probability of overlap. A close agreement between the winzer criterion and overlap probability was demonstrated. A permissible blasting unit capable of delivering a maximum firing energy of 4.0 J and a digital oscilloscope were used to measure the delay time with an accuracy of plus or minus 0.25 Ms. Another oscilloscope and a pulse transformer were used to record firing current. Experimental data indicated negligible overlap probability in detonators of shorter delay periods: periods 1 to 4, which correspond to 25 to 250 ms. However, a significant probability of overlap was detected in some detonators of longer delay periods: periods 5 to 9, which correspond to 300 to 500 ms. [Description provided by NIOSH]
• Subjects:
  Emergencies Mining Occupational Health Respiratory System Safety
• Keywords:
  Mining-industry; Underground-mining; Coal-mining; Explosive-devices; Explosives; Explosive-hazards
• Source:
  Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 8888, 1985 Jan; :1-18
• Series:
  Mining Publications   ; NIOSH Numbered Publications  
• Subseries:
  Report of Investigations
• Document Type:
  Text
• Genre:
  Report
• Place as Subject:
  OSHA Region 3 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PRC - Pittsburgh Research Center
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  26 pdf pages
• NIOSHTIC Number:
  nn:10004523
• NTIS Accession Number:
  PB86-112513
• Contact Point Address:
  NIOSH, Pittsburgh Research Laboratory, P.O. Box 18070, Pittsburgh, PA 15236
• Federal Fiscal Year:
  1985
• Peer Reviewed:
  False
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:bbf285761533e60543cbe7b981cc6dba63eb2ef3f2321eb1934b701199aae1e462d841398cafe6a1fa953d30a9f54eea2afb6a4e95f0e27818eecdc0234162f7
• Download URL:
  https://stacks.cdc.gov/view/cdc/9607/cdc_9607_DS1.pdf
• File Type:
  [PDF - 1.90 MB ]