Visual Performance for Incandescent and Solid-State Cap Lamps in an Underground Mining Environment

Details

• Personal Author:
  Sammarco, John J., PH.D. ; Lutz, Timothy
• Corporate Authors:
  National Institute for Occupational Safety and Health
• Description:
  Miners depend most heavily on visual cues to recognize underground mining hazards; consequently, illumination plays a critical role in miners’ safety. Some hazards are located in the miners’ peripheral field-of-view (10 degrees to about 60 degrees off-axis) or on-axis (0 degrees). The objective of this research was to determine if there were visual performance improvements when using solid-state cap lamps with light-emitting diodes (LEDs) as compared to incandescent light bulbs commonly used in miner cap lamps. Recent research has indicated that an increased short-wavelength content of the spectral power distribution of LEDs relative to incandescent lamps improves peripheral visual performance for low-light (mesopic) conditions. The visual performances of nine subjects were quantified by measuring the subjects’ speed and accuracy in detecting floor objects located on axis and at ±20 degrees off axis. The objects were located near field (1.83 meters) and far field (3.66 meters). Upon presentation of the objects, subjects would count and point to each object using a red-laser pointer. The object detection response time and number of missed objects were recorded. The results of the visual performance comparison for an LED, a prototype LED, and an incandescent cap lamp are presented. There we no missed objects when subjects used the LED-based cap lamps but, there were three missed object occurrences when subjects used the incandescent cap lamp. The mean detection time when using the incandescent cap lamp was 55.3% greater than the prototype LED cap lamp and 43.5% greater than the LED cap lamp. It can be inferred from this data that the spectral distribution of LED-based cap lamps could enable significant visual performance improvements as compared to incandescent cap lamps1.
• Subjects:
  Mining
• Source:
  IAS '07: Conference Record of the 2007 IEEE Industry Applications Conference: Forty-second IAS Annual Meeting, September 23-27, 2007, New Orleans, Louisiana. Piscataway, NJ: Institute of Electrical and Electronics Engineers, 2007 Sep; 4:2090-2095
• Document Type:
  Text
• Genre:
  Conference Publications
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• NIOSHTIC Number:
  nn:20039791
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:44352deb8ede72b8136ff40e08a9902adcd7bd46f08761596fee55253cc6c723637db550690331db028a0c76a297aacb03c22dd9a53137154d6c0d12f2a9c8b7
• Download URL:
  https://stacks.cdc.gov/view/cdc/9879/cdc_9879_DS1.pdf
• File Type:
  [PDF - 179.43 KB ]