title: Intercollegiate usage schedule and the impact resistance of used football helmet faceshields.
abstract: OBJECTIVE
  Although new polycarbonate helmet faceshields can withstand impacts exceeding forces of 2,400 N, repeated impacts and ultraviolet radiation degrade the structural integrity. In this study, the impact resistances of unused, solar-radiated, and of game-used faceshields were analyzed. Also, Division 1 National Collegiate Athletic Association football programs were surveyed concerning their faceshield practices.
  
  
  METHODS
  Impact resistance was tested by impacting faceshields with baseballs at velocities exceeding 67.1 m/s. Twenty-four new faceshields were exposed to southern daylight, 3 hours per day for 3 months before testing. Subsequent testing was performed on 60 game-used faceshields. Additionally, a faceshield utilization survey was distributed to 117 college programs.
  
  
  RESULTS
  Solar-irradiated shields did not fail at maximum test velocity. The survivability of nonimpacted shields was greater than game-worn shields (P = 0.0003). Fifty-nine surveys were returned with 58 programs reporting faceshield use. Approximately 21 players per program use a faceshield. The main reason reported for use was aesthetic. Only 21% of reporting programs require a faceshield for players with reduced visual acuity in 1 eye.
  
  
  CONCLUSIONS
  Faceshields lose impact resistance with typical use. Programs should incorporate a policy for replacement and require that players with reduced vision in at least 1 eye wear a faceshield.
authors.affiliation: The Ohio State University College of Optometry, Columbus, OH 43210, USA. azimmerman@optometry.osu.edu
authors.forename: Aaron B
authors.initials: AB
authors.lastname: Zimmerman
authors.forename: Gregory W
authors.initials: GW
authors.lastname: Good
authors.forename: W Randy
authors.initials: WR
authors.lastname: McLaughlin
authors.forename: Steven E
authors.initials: SE
authors.lastname: Katz
mesh_terms: D004868:Equipment Failure; D005145:Face; D005538:Football; D006260:Head Protective Devices; D006801:Humans; D011076:Polycarboxylate Cement; D011482:Protective Devices / Q000592:standards* / Q000706:statistics & numerical data*; D013472:Sunlight; D014495:Universities
chemical_list: D011076:Polycarboxylate Cement; C005506:polycarbonate