title: Comparative performance of playground surfacing materials including conditions of extreme non-compliance.
abstract: OBJECTIVE
  A recent case series study found that only 4.7% of 402 playgrounds in which arm fractures occurred in Victorian schools complied with the recommended 20 cm depth of tanbark. Tanbark depths at fall sites varied between 0-27 cm and the mean was 11.1 (5.0) cm. The purposes of the present study were to (1) measure impact attenuation properties of shallow and compacted depths of tanbark; (2) validate laboratory measurements with in situ data; (3) compare impact attenuation properties of compacted tanbark with an Australian manufactured rubber based surface material; and (4) study the impact performance of rubber and tanbark hybrid surfacing.
  
  
  METHODS
  A standard test headform was dropped on tanbark and rubber surfaces in a laboratory setting to measure peak impact deceleration and head injury criterion (HIC) values. Variations in surface depth ranged from 2 cm-20 cm (tanbark) and 2 cm-9 cm (rubber). Drop height ranged from 0.5 m-2.5 m.
  
  
  RESULTS
  Peak deceleration and HIC increased with increasing drop height and decreasing surface depth. Laboratory measurements at depths less than 8 cm overestimated peak deceleration and HIC values compared with in situ playground measurements. Impact attenuation of a 9 cm thick bilaminate rubber material was comparable to that of an 18 cm depth of compacted tanbark. Rubber-tanbark hybrid surfaces showed improved impact attenuation over individual surfaces.
  
  
  CONCLUSIONS
  Compacted tanbark of depth less than 8 cm is ineffective in attenuating playground falls, resulting in excessive impact deceleration and HIC values. Shallow and compacted tanbark found in many Victorian school playgrounds poses a high risk for severe head injury. This calls for stricter enforcement of playground surface depth compliance.
authors.affiliation: Accident Research Centre, Monash University, Melbourne, Australia. gunatilaka@general.monash.edu.au
authors.forename: A H
authors.initials: AH
authors.lastname: Gunatilaka
authors.forename: S
authors.initials: S
authors.lastname: Sherker
authors.forename: J
authors.initials: J
authors.lastname: Ozanne-Smith
mesh_terms: D000056:Accident Prevention; D002648:Child; D003252:Construction Materials / Q000592:standards*; D006259:Craniocerebral Trauma / Q000517:prevention & control*; D004779:Environment Design / Q000592:standards*; D017408:Guidelines as Topic; D006801:Humans; D019563:Mechanics; D010988:Play and Playthings; D012307:Risk Factors; D012408:Rubber
chemical_list: D012408:Rubber