title: Digital 3-d headforms representative of chinese workers.
abstract: Headforms are useful for designing and testing various types of personal protective equipment used to protect millions of workers from occupational hazards in China. Although the Chinese national standard of head-and-face dimensions for adults was first published in 1981, headforms based on those dimensions were never developed. In 2006, an anthropometric survey of 3000 Chinese civilian workers was conducted. As part of the survey, 350 subjects were scanned with a Cyberware 3D Rapid Digitizer. The manual measurements and 3-D digital scans from this survey were used to develop 3-D digital headforms that represent Chinese workers.
  
  
  OBJECTIVE
  The objective of this study was to develop headforms that represent today's Chinese workers.
  
  
  METHODS
  Ten facial dimensions relevant to respirator fit were chosen for defining a principal component analysis model which divides the user population into five face size categories. Mean facial dimensions from manual measurements were then computed to target the ideal facial dimensions for each size category. Five scans were chosen from each face size category to be used in the construction process. Selected scans were then averaged to construct a representative headform for each face size category.
  
  
  RESULTS
  Five digital 3-D headforms were developed: small, medium, large, long/narrow, and short/wide. These distinct sizes of digital 3-D headforms take into account the linear distance between landmarks as well as the surface contours captured during the 3-D scan. The dimensions of constructed headforms were within approximately 4 mm between the corresponding computed means and manual measurements of anthropometric landmarks for the sample population in each size category.
  
  
  CONCLUSIONS
  These new headforms represent the facial size and shape distribution of current Chinese workers and may be useful for respirator research and development. The Chinese medium headform has a wider face width, shorter face length, and smaller nose protrusion when compared with the current U.S. standard headforms. Upon validation, it may be useful to incorporate these dimensions into Chinese and international respiratory protective devices standards.
authors.affiliation: Department of Occupational and Environmental Health and Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Yu
authors.forename: Stacey
authors.initials: S
authors.lastname: Benson
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Cheng
authors.forename: James
authors.initials: J
authors.lastname: Hsiao
authors.forename: Yuewei
authors.initials: Y
authors.lastname: Liu
authors.forename: Ziqing
authors.initials: Z
authors.lastname: Zhuang
authors.forename: Weihong
authors.initials: W
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000886:Anthropometry; D002681:China; D004867:Equipment Design / Q000379:methods*; D005145:Face / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D012134:Respiratory Protective Devices; D055815:Young Adult