title: Time saved with the use of emergency warning lights and siren while responding to requests for emergency medical aid in a rural environment.
abstract: OBJECTIVE
  To determine whether the use of warning lights and siren saves a significant amount of time for ambulances responding to requests for emergency medical aid in a rural emergency medical services (EMS) setting.
  
  
  METHODS
  A prospective design was used to determine run times for ambulances responding to calls with lights and siren (code 3) and for a similarly equipped "chase" ambulance traveling to the same destination via the same route without lights and siren, while obeying all traffic laws (code 2) within a rural setting. Data were collected for run time intervals, distance traveled, visibility, road surface conditions, time of day, and day of the week. Descriptive statistics, a paired Student's t-test, and analysis of variance were used to test for significant differences between code 2 and code 3 operations, as well as the other variables listed above.
  
  
  RESULTS
  Sixty-seven runs were timed during a 21-month period. The average code 3 response interval was 8.51 minutes. The average code 2 response interval was 12.14 minutes. The 3.63 minutes saved on average represents significant time savings of 30.9% (p < 0.01). Shorter runs had higher time savings per mile than the longer runs. Run distance was the only variable that was statistically significant in affecting time saved during a code 3 response.
  
  
  CONCLUSIONS
  Code 3 operation by EMS personnel in a rural EMS setting saved significant time over code 2 operation when traveling to a call.
authors.affiliation: Department of Emergency Medicine, Hennepin County Medical Center, Minneapolis, Minnesota 55415, USA. ho911doc@qwest.net
authors.forename: J
authors.initials: J
authors.lastname: Ho
authors.forename: M
authors.initials: M
authors.lastname: Lindquist
mesh_terms: D000552:Ambulances; D000704:Analysis of Variance; D001334:Automobile Driving; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D006801:Humans; D008029:Lighting; D008910:Minnesota; D011446:Prospective Studies; D019035:Rural Health Services / Q000706:statistics & numerical data*; D013016:Sound; D013997:Time Factors