title: Monitoring of the sleep patterns of shift workers in the automotive industry.
abstract: OBJECTIVE
  The effect of shift schedules on the amount of sleep that workers receive is an important factor in workplace health and safety as well as the employees' overall quality of life. The objective of this study is to compare sleep period among workers engaging in each of the three-shift work.
  
  
  METHODS
  The amount of sleep (sleep period) that male workers with rotating shift schedules received was measured using accelerometers. The mean age of the 16 male workers enrolled in this study was 54.3 years (one standard deviation, 6.7 years). Thirteen participants ranged in age from 51 to 60 years of age, and the other three participants were 32, 48, and 50 years old. Work shifts were rotated on a weekly basis and were categorized into three periods: shift-1 (8:00 to 17:00), shift-2 (15:00 to 23:50), and shift-3 (23:30 to 8:15). Each work week consisted of 5 days.
  
  
  RESULTS
  No significant differences were observed in the mean sleep period for each of the three shifts. However, the sleep periods during shift-1 or shift-2 tended to be longer than that obtained during shift-3. No effect of age on the length of the sleep period was observed.
  
  
  CONCLUSIONS
  Rotating shift-work did not affect the amount of sleep that workers obtained. However, a comparison with previous study results suggests that morning shifts (starting at 6 AM) and day shifts (starting at 8 AM) may have different effects on sleep time.
authors.affiliation: Department of Hygiene and Public Health, Nippon Medical School, Tokyo, Japan. kawada@nms.ac.jp
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Kawada
authors.forename: Takako
authors.initials: T
authors.lastname: Shimizu
authors.forename: Yushiro
authors.initials: Y
authors.lastname: Kuratomi
authors.forename: Sachiko
authors.initials: S
authors.lastname: Suto
authors.forename: Tomoe
authors.initials: T
authors.lastname: Kanai
authors.forename: Akemi
authors.initials: A
authors.lastname: Nishime
authors.forename: Noriko
authors.initials: N
authors.lastname: Nakano
mesh_terms: D056044:Actigraphy / Q000295:instrumentation; D001336:Automobiles; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D007221:Industry; D007564:Japan; D008297:Male; D008875:Middle Aged; D012890:Sleep; D014940:Work Schedule Tolerance