title: An investigation of heat stress effects on time-sharing performance.
abstract: A study was conducted to investigate the effects of heat stress on time-sharing performance. Twelve participants performed three dual-task scenarios and a multiple-task scenario for 2 h in each of six climates. The climates were obtained by generating each of three wet bulb globe temperatures (WBGT; 22, 28 and 34 degrees C) with two relative humidity levels (30 and 70%). The dual tasks selected from the Criterion Task Set (CTS) were: (1) display monitoring with mathematical processing; (2) memory search with mathematical processing; and (3) unstable tracking with memory search. The multiple task scenario was generated using the SYNTASK software. The results indicated a significant heat stress effect on CTS display monitoring and unstable tracking performance and on the SYNTASK visual monitoring and auditory discrimination tasks. Additionally, at 34 degrees C WBGT, 70% relative humidity was more detrimental to performance than 30% relative humidity. Results were interpreted using the Maximal Adaptability Model and Shingledecker's information processing stage/resource framework. To describe the results in an orderly manner, the authors propose the concept of heat stress selectivity effects. In addition, the results were used to evaluate whether the most recent NIOSH recommended heat stress standard, which is based solely on physiological and medical criteria, protects time-sharing performance. It was concluded that the NIOSH criterion does offer protection up to 28 degrees C WBGT.
authors.affiliation: Pershing Technology Group, One Pershing Plaza, Jersey City, NJ 07399, USA. ivasmatzidis@pershing.com
authors.forename: Ioannis
authors.initials: I
authors.lastname: Vasmatzidis
authors.forename: Robert E
authors.initials: RE
authors.lastname: Schlegel
authors.forename: Peter A
authors.initials: PA
authors.lastname: Hancock
mesh_terms: D000328:Adult; D002980:Climate; D018882:Heat Stress Disorders; D006801:Humans; D006813:Humidity; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D009314:National Institute for Occupational Safety and Health, U.S.; D016273:Occupational Exposure / Q000009:adverse effects*; D013647:Task Performance and Analysis; D013996:Time and Motion Studies; D014481:United States