ABSTRACT
10 male subjects participated in the environmental simulation study to evaluate the operation ergonomics at high-temperature in the cockpit. Grip strength, perception, dexterity, reaction and intelligence were measured respectively during the tests at 40 degrees C and 45 degrees C, simulating the high-temperatures in a simulation cockpit chamber. Then the data obtained were compared to the combined index of heat stress (CIHS). The average values of each item of the subjects' performance at the two different temperatures are compared. The results indicated that CIHS exceeded the heat stress safety line after 45 min at 40 degrees C, grip strength decreased by 12%, and perception increased by 2.89 times. In contrast, at 45 degrees C, CIHS exceeded the safety line after 20 min, grip strength decreased by 3.2%, and perception increased by 4.36 times. However, Finger dexterity was less affected. Reaction ability was first accelerated, and then slowed down. The error rate in the intelligence test increased to a greater extent. At the high temperatures, the minimum perception was the most affected, followed by grip strength, reaction and finger dexterity were less affected, while the intelligence did not decline, but rise.
Subject(s)
Adult , Humans , Male , Young Adult , Aerospace Medicine , Aircraft , Computer Simulation , Ergonomics , Heat Stress Disorders , Hot TemperatureABSTRACT
Objective In order to provide important theoretical basis for further improving design of DC-7/7A high altitude partial pressure suit and FTF-2 air ventilation suit (named as A suit and B suit), the performance of ventilating heat dissipation of DC-7/7A and FTF-2 was studied. Methods Five healthy volunteers were enrolled to took participate in A group and B group tests. Environmental weather conditions for A and B suits were set at Tdb 40℃ and 45℃,rh 45% and 40% respectively, and the test time was 90min and 120 min respectively. Results During the test for A group and B group, Ts ranged from 31.5℃ to 34.5℃ for human comfort. Average skin temperatures of the lower part of the body were from 33.1℃ to 33.8℃. Skin temperatures of the legs did not obviously change or slightly lowered. Heart rate showed an increase of 12 beats/min and 14 beats/min. Sweat quantities were measured to be 0.288?0.056kg/1.5h and 0.445kg?0.077 kg/2h respectively. Evaporation rates were 77.4?3.6% and 84.2?2.4% respectively. Subjective uncomfortable sensation was more obvious as test time went on. Conclusion The results of the ventilating heat dissipation for both groups were quite good, but the findings suggested that the number of the ventilating holes for some important sites should shall be re-considered. Pilots wearing A group and B group with ventilation function would still suffer from mild heat stress and obvious subjective discomfort in hot enviroment.
ABSTRACT
The apparatus introduced in this paper can be used to measure and record the realtime environmental parameters and such physical information of individual protection equipment as the temperature,thermal current and thermal insulating value.The apparatus has several advantages including high accuracy,practicability,reliability and easy to operate.