Safety

Enclosed Vehicle Excessive Heat

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Enclosed Vehicle Excessive Heat, Enclosed Vehicle Greenhouse Effect

  • Mechanism
  1. Solar radiation passes through vehicle windows and is absorbed by seats, floor and other internal objects
  2. Vehicle glass traps much of the solar radiation within the vehicle, and it continues to accumulate
  • Epidemiology
  1. Incidence of pediatric death in U.S. from Heat Stroke related to being left in car: 28-43 per year
  • Precautions
  1. Children left alone even for minutes within closed cars are at significant risk for Heat Stroke and death
  • Findings
  • Heat increase within car over time
  1. General
    1. Temperature within a closed car rises as much as 7 F every 5 min
    2. Within 1 hour, Temperature increases within car >40 F more than outside Temperature
    3. Cracking windows by 1.5 inches does not signiifcantly affect heat increase
      1. Some studies have found minimal effect even with windows cracked 8 inches (20 cm)
  2. Outside air Temperature 70 F
    1. Internal car Temperature at 20 min: 99 F
    2. Internal car Temperature at 40 min: 108 F
    3. Internal car Temperature at 60 min: 113 F
  3. Outside air Temperature 80 F
    1. Internal car Temperature at 20 min: 109 F
    2. Internal car Temperature at 40 min: 118 F
    3. Internal car Temperature at 60 min: 123 F
  4. Outside air Temperature 90 F
    1. Internal car Temperature at 20 min: 119 F
    2. Internal car Temperature at 40 min: 128 F
    3. Internal car Temperature at 60 min: 133 F
  5. Outside air Temperature 95 F
    1. Internal car Temperature at 20 min: 124 F
    2. Internal car Temperature at 40 min: 133 F
    3. Internal car Temperature at 60 min: 138 F
  • References
  1. Herbert in Herbert (2015) EM:Rap 15(6):14
  2. King (1981) Pediatrics 68:579-82 [PubMed]
  3. McLaren (2005) Pediatrics 116(1): e109-12 +PMID:15995010 [PubMed]
    1. http://pediatrics.aappublications.org/content/116/1/e109.full.pdf+html
  4. Roberts (1976) Pediatrics 58:101–4 [PubMed]